Table of Content

20 October 2010, Volume 19 Issue 5

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Analysis of cloning and sequence characteristics of cDNA encoding the GBSS I gene from tubers of Solanum tuberosum

SHEN Bao-yun, LIU Yu-hui, ZHANG Jun-lian, WANG Di

2010, 19(5):  1-8. 

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The cDNA clone encoding GBSSⅠwas obtained by extracting total RNA from tubers of Solanum tuberosum CV. Gannongshu NO.2 using an RNA isolation system, RT-PCR (reverse transcription-polymerase chain reaction), then measuring and analyzing the DNA sequence. The full-length of cDNA was 1 824 bp, which contained 607 amino acids and a termination codon: the homology was 99.78% compared with the original sequence (Accession Number X58453), but the homologies were very low compared with other families. The gene has the registration number EU403426 in GenBank. The protein function and structure of the GBSSⅠgene cDNA sequence were predicted and analyzed using related software of bioinformatics. The protein had three completely conserved domains as in other GBSS proteins of 15 plants and it had a number of important functional sites. It also had a tertiary structure similar to starch synthase of Agrobacterium, which suggests that the protein functioned in starch synthesis.

Agrobacterium-mediated transformation of Brachypodium distachyon through embryogenic calli derived from immature embryos

WU Xue-li, LIU Jin-xing, Klaus K Nielsen,YANG Zhi-min,GAO Cai-xia

2010, 19(5):  9-16. 

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A very efficient transformation system, using Agrobacterium-mediated transformation, has been developed for the production of transgenic plants of Brachypodium distachyon. Embryogenic calli initiated from immature embryos were transformed with Agrobacterium tumefaciens strain AGL1 carrying the binary vector pDM805, coding for the phosphinothricin acetyltransferase (bar) and β-glucuronidase (uidA) genes. Bialaphos was used as the selective agent throughout all phases of tissue culture. Transformation efficiency was strongly influenced by genotype, size of immature embryos and age of embryogenic callus. An average transformation efficiency of 38.5% was obtained using 5 to 8 week-old embryogenic callus as transformation targets and the highest transformation efficiency achieved was 43.1%. The existence and integration of the bar gene in transgenic plants was confirmed by PCR (polymerase chain reaction).

Responses of climatic potential grassland productivity to climatic change in an alpine meadow area over the Nujiang Basin, Tibet from 1980 to 2008

ZHOU Kan-she, DU Jun, YUAN Lei, MA Peng-fei, LIU Yi-lan

2010, 19(5):  17-24. 

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Annual mean temperature and precipitation data from nine meteorological stations in the Nujiang Basin of Tibet over the period 1980 to 2008 were used to compute the climatic potential grassland productivity using Miami models, and to analyse grassland spatial distribution and variation. Over the past 29 years, climatic potential grassland productivity of the upper reaches (from Amdo to Tengchen) of the Nujiang Basin were mainly affected by the temperature conditions and the mid-lower reaches (from Lhorong to Zayul) by precipitation. From the upper to lower reaches there were generally uneven geographical distributions that changed markedly with age. Correlation analysis demonstrated that climatic potential productivity was significantly negatively correlated with annual mean precipitation (P＜0.01), and with the mean temperature of the main growing season (P＜0.05). There were some regional differences in distribution of climatic potential grassland productivity which was significantly higher in the downstream region than in the upper reaches, The climate will trend to a “warmer and wetter-type” due to temperature rise and precipitation increases, so the climatic potential grassland productivity may be increased in the Nujiang Basin over the next 90 years. The research indicates that the the warmer, wetter trend in the Nujiang Basin will benefit the development of pasture husbandry, especially for improving the eco-environment.

Effect of γ-irradiation on callus regeneration and salt tolerance in Manilagrass

JIA Yu-fang, CHEN Shu, CHAI Ming-liang

2010, 19(5):  25-30. 

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Embryogenic calluses induced from stolons of Manilagrass (Zoysia matrelia) were treated with ⁶⁰Co γ-irradiation at doses of 0 Gy (control) and 10 Gy. Regeneration of the callus, activities of catalase (CAT), superoxide dismutase (SOD), peroxidase (POD) enzymes, and proline content in the regenerated plants were measured. The treated materials were screened on MS basal media with different concentrations of NaCl (0%, 0.5%, 1.0%, 1.5%, and 2.0%). The results showed that 10 Gy ⁶⁰Co γ-irradiation had a significant promoting effect on callus regeneration and differentiation, and that the percentage of explants that formed more than 3 plantlets per explant was increased by 11.25%. However, the regeneration rate of the callus was reduced by 8.75%. 10 Gy ⁶⁰Co γ-irradiation of regenerated plants resulted in increases of CAT activity and proline content by 16.02% and 1.20 times, respectively. There were no significant changes in the activities of SOD and POD enzymes in the regenerated plants from calluses treated with 10 Gy γ-irradiation, compared with that of the controls. The maximum number of regenerated plants were obtained from calluses treated with 10Gy ⁶⁰Co γ-irradiation and grown on medium with 1.0% NaCl - 9.60% of the calluses formed plantlets. Regenerated plants maintained vigorous growth after transfer to rooting medium with 1.0% NaCl.

Effects of feeding baled TMR on lactation performance, apparent digestibility, and blood metabolites in lactating dairy cows

ZHOU Zhen-feng, WANG Jing, WANG Jia-qi, GUO Wei-jie,
SONG Zen-ting, ZHANG Jun-yu, BU Deng-pan

2010, 19(5):  31-37. 

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To evaluate the effect of baled TMR (total mixed ration) on lactation performance, apparent digestibility and blood metabolites, twenty-four Holstein cows at mid-lactation stage (124±20 days in milk) were randomly assigned to two groups for a 10-weeks feeding trial. In the control, 12 cows were fed by traditional separate feeding of forage and concentrate while the other 12 cows were fed directly by baled TMR feeding. The ingredients and nutrient composition of the diets were the same in both the separate feeding and baled TMR feeding. The forage to concentrate ratio in the diets was 50∶50, and the moisture content of baled TMR was 50%.The baled TMR feeding significantly increased dry matter intake (P<0.05) and numerically increased the milk yield (7.69%) and 3.5% fat corrected milk (5.20%) compared with the separate feeding. No significant differences occurred in milk composition and nutrient production between the baled TMR feeding and the separate feeding. The apparent digestibility of crude protein and ether extract was significantly increased in the baled TMR feeding group (P<0.05), and an increasing trend occurred in the apparent digestibility of dry matter (P<0.1). The baled TMR feeding method significantly reduced the blood urea nitrogen content in blood serum, but the effect on other blood indices was similar to that of separate feeding. In conclusion, baled TMR technology can be an effective method of total mixed ration distribution and should be promoted in small and medium-scale dairy farms to improve their performance and income from dairy production.

Effects of grass mixture cultivated in light, moderate and serious alkali-saline grassland on rumen fermentation, feed digestibility and nitrogen balance in sheep

WANG Cong, LIU Qiang, DONG Kuan-hu, ZHAO Xiang, LIU Sheng-qiang,
HE Ting-ting, LIU Zhuang-yu

2010, 19(5):  38-44. 

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The objective was to evaluate effects of grass mixture cultivated in light, moderate and serious alkali-saline grassland on rumen fermentation, feed digestibility and nitrogen balance in sheep. Twelve first filial generation (F1) sire growing-fattening sheep of a cross between Chinese Inner Mongolian Fine-wool and German Mutton Merino, averaging 5.0 months of age and 34.6±0.57 kg of body weight (BW), were arranged into four groups at random. Sheep in control group fed concentrate and corn silage, while sheep in treatment I, Ⅱ and III fed concentrate and grass mixture (Elymus dahuricus, Puccinellia distans and Astragalus adsurgens) cultivated in light, moderate and serious alkali-saline grassland, respectively. Sheep were fed 600 g concentrate daily and rough forage provided ad libitum. The results showed that ruminal pH in treatment I and II was lower than the control and treatment III, whereas total VFA concentration was higher than control (P<0.05). Molar proportion of propionate, butyrate, valerate, isobutyrate and isovalerate in treatments was higher than control, but molar proportion of acetate and the ratio of acetate to propionate in treatments were lower than control (P<0.05). Intake of DM and OM were not affected, but NDF intake in treatment III was higher than other groups, ADF intake in treatment II and III was higher than control (P<0.05). Digestibilities of DM, OM, NFE and energy in treatment III was lower than treatment II and I, treatment II and I lower than control. Digestibilities of CP, EE, NDF and ADF were significantly affected by treatments, treatment III, II, I and control is in turn from low to high. Intake of nitrogen in treatment III and II was lower than control and treatment I. Nitrogen retained and ratio of nitrogen retained to digestible nitrogen was significantly affected by treatments, treatment III, II, I and control is in turn from low to high. The results indicated that feeding grass mixture cultivated in light and moderate alkali-saline grassland potentially improves rumen fermentation, but decreased feed digestibility and nitrogen utilization in sheep. Rumen fermentation, feed digestibility and nitrogen balance were affected negatively in sheep fed grass mixture cultivated in serious alkali-saline grassland alone.

Dynamic changes of grazing sheep body gains and ruminal fermentation parameters on sandy recovering grassland

Ta-na, GUI Rong, WEI Ri-hua, ZHAO Shan-zhi

2010, 19(5):  45-50. 

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A sheep grazing experiment was carried out at the Inner Mongolian, Zhenglan banner, Hunshandake sandy recovering grassland in the warm season to determine body weight gains and ruminal fermentation parameters under rotational grazing and continuous grazing. Sheep body weight gains were evident at 4 months, and averaged 2.46, 5.08, 5.52, and 2.29 kg/month, respectively in the three experimental groups. There was no obvious difference between sheep weight under continuous grazing and rotational grazing. Sheep had high rumen fermentation levels from July to August, from fasting to intake after 7 h the rumen pH, NH₃-N concentration and TVFA (total volatility fatty acid) concentration range were changed as 7.01－6.38－6.47－6.77, 6.02－9.26－10.75－10.82 mg/100 mL and 31.37－42.99－58.55－65.28 mmol/L, respectively. Therefore, sheep can produce higher body gains and better rumen fermentation when grazed on sandy recovering grassland after a 5-6 year fenced recovery period.

A preliminary study of assessing the feasibility of using physiological and biochemical parameters to assess water hyacinth biogas slurry for soaking seeds to improve germination characteristics

XUE Yan-feng, SHI Zhi-qi, YAN Shao-hua, ZHENG Jian-chu, CHANG Zhi-zhou

2010, 19(5):  51-56. 

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The seeds of Chinese cabbage (Brassica rapa) were soaked in a range of concentrations of biogas slurry from water hyacinth (Eichhornia crassipes) fermentation. The effects of the slurry on seed germination, growth, chlorophyll content and changes of antioxidant enzymes in Chinese cabbages were studied. The germination energy and germination percentage increased with an increase of biogas slurry concentration, but the differences were not significant compared with the controls. The germination index and vigor index increased markedly with an increased concentration of biogas slurry. With the exception of Z1 and Z4, the root lengths increased significantly compared with the controls as did shoot height, fresh weight and dry weight: All these parameters increased markedly with an increase of biogas slurry concentration. Although the parameters decreased in the treatment of purified biogas slurry, they were significantly different from the control. The trend of chlorophyll content and antioxidant enzyme activities changed as for the growth parameters. Therefore, the physiological and biochemical parameters could be used as a simple index for quickly assessing the feasibility of soaking seeds in water hyacinth biogas slurry to improve germination.

Research on allelopathic effects of Allium macrostemon on three main weeds (Digitaria sanguinalis, Echinochloa crusgalli and Amaranthus retroflexus) in peanut fields

ZHANG Yue-li, QIN Li-qin, GAO Xing-xiang, LI Mei, LI Xin-guo,
MENG Jing-jing, WAN Shu-bo

2010, 19(5):  57-62. 

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Allelopathic effects of aqueous extract from Allium macrostemon were tested in Petri-dishes. The extract strongly inhibited germination and seedling growth of Digitaria sanguinalis, Echinochloa crusgalli and Amaranthus retroflexus. D. sanguinalis and A. retroflexus were more sensitive to the extract than E. crusgalli. At 0.025 g/mL concentration, the germination rates of A. retroflexus, D. sanguinalis and E. crusgalli were 38.46%, 50.00% and 85.71%, respectively. On one seed, the germination speed was reflected in the germination rate, but was more sensitive to the extract. The roots were more strongly inhibited than seedling height at the same concentration.

A comparison of stress effects between chloridion and sodium ion on grain amaranth seedlings under NaCl stress

LI Hong-yan, ZHENG Qing-song, JIANG Chao-qiang, LIU Zhao-pu, LIU Guo-hong, XIN Ben-rong

2010, 19(5):  63-70. 

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Ion-specific stresses of Cl^- and Na⁺ on biomass, growth rate, chlorophyll contents, photosynthesis traits, and ion contents of grain amaranth seedlings were studied and compared under iso-osmotic (-0.096 MPa,-0.198 MPa,-0.437 MPa) salt solutions (NaCl, Cl-salt, and Na-salt) for 10 d in sand culture in a greenhouse. Both -0.096 and -0.198 MPa Cl-salt increased the dry weight of grain amaranth seedlings compared with the control whereas -0.437 MPa NaCl, Na-salt and Cl-salt both significantly reduced plant dry weight. The order of growth inhibition under different treatments with high pressure conditions (-0.437 MPa) was Na-salt > NaCl > Cl-salt. Net photosynthetic rate (Pn), transpiration rate (Tr) and stomatal conductance (Gs) of grain amaranth seedlings in descending order of magnitude suppression was Na-salt>NaCl>Cl-salt treatment. The Na⁺ contents in the leaf were lower those of the stem and root under NaCl and Na-salt stress. Ion selectivity of imbibition or transportation (S_K,Na) in roots, stems, and leaves were all increased under -0.096, -0.198, -0.437 MPa NaCl and Na-salt treatments. In general, growth inhibition of grain amaranth seedlings from Na-salt stress was much more than that from Cl-salt stress. Salt adaptation of grain amaranth seedlings to a certain degree to Na⁺ was due to high K⁺ selective absorption and transport.

Effects of NaCl stress on proline metabolism of Achnatherum splendens seedling

DONG Qiu-li, XIA Fang-shan, DONG Kuan-hu

2010, 19(5):  71-76. 

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Under varying levels of NaCl stress, the proline(Pro), pyrroline-5-carboxylate synthetase(P5CS), ornithine-oxo-acid transaminase(δ-OAT), and proline dehydragenase(ProDH) among leaves and roots of Achnatherum splendens were determined. The results showed that the proline metabolism synthesis path-way of the A. splendens seedling is mainly on the pathway of Glutamate.The proline content increased with the increase of NaCl,and the proline content in leaves and in roots were the highest that could be up to 585.77 and 303.36 μg/g FW respectively at the concentration of 500 mmol/L NaCl. The activity of δ-OAT was significantly lower than that in control(P<0.05), and declined with the increasing of the NaCl concentration. The activity of P5CS from the roots of Achnatherum splendens was significantly higher than leaves under the same concentration(P<0.05). At the concentration of 300 mmol/L NaCl,the P5CS activity in leaves and roots reached the 7.44 and 20.81 U/mg Protein respectively. The activity of ProDH in leaves were higher than in control, and could be up to 1.7 times than the control, but didn't change significantly in roots.

Effects and early mechanisms of complex salt and alkali conditions on seed germination and seedling growth of Flaveria bidentis

FENG Jian-yong, PANG Min-hao, ZHANG Jin-lin, LIU Ying-chao

2010, 19(5):  77-86. 

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An alkali-saline mixed stress was used to simulate the effect of salt-alkalinized soil on the germination rate, germination index, seeding height, and root length of Flaveria bidentis. Simultaneously, the effects of the stress on antioxidant enzyme (SOD, POD, CAT) activities, chlorophyll content, and MDA (malondialdehyde) were investigated. The features of salt-alkalinized soil in Hebei were simulated using 24 different alkali-saline conditions with salinities and pH obtained by mixing two neutral salts (NaCl and Na₂SO₄) and two alkaline salts (NaHCO₃ and Na₂CO₃) in various proportions. There was a negative effect of salt on the germination rate, germination vigor, seeding height, and root lengths of four groups; A, B, C, and D. At the same alkalinity, the germination rate, germination vigor, seeding height, and root length of all treatments increased significantly with reduced alkalinity. Statistical analysis showed that salinity was the dominant stress factor to inhibit seed germination and seedling growth of F. bidentis, while other indices, such as pH, had no decisive effect on germination. After saline-alkali stress, the relative rate of chlorophyll destruction, membrane permeability, and MDA of the F. bidentis leaves increased. In the early stages of saline-alkali stress, SOD and POD activity increased, but CAT activity was not significantly different from the control. This showed that F. bidentis leaves mainly rely on SOD and POD activity to temporarily maintain the dynamic equilibrium of reactive oxygen generation and scavenging.

Effects of Achnatherum inebrians infected with Neotyphodium endophyte on accompanying species of Stipa capillata and Poa sphondylodes

HUANG Xi, LI Chun-jie, NAN Zhi-biao, YANG Song, CHAI Qing

2010, 19(5):  87-93. 

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Drunken horse grass (Achnatherum inebrians), an intoxicating grass in native grasslands of Northwest China, often grows in conjunction with Stipa capillata and Poa sphondylodes. Competitive interactions between endophyte infected (E+) A. inebrians and endophyte free (E-) A. inebrians with S. capillata and P. sphondylodes were investigated. E+ A. inebrians had a significant inhibition effect on percentage seed germination and seedling growth (P<0.05), which declined significantly by 17.1%, 13.6%, respectively. Similarly, seedling length declined 23.2% and by 16.3%; E+ plants had significant inhibition effects on tiller heights of S. capillata and P. sphondylodes from the first week after germination (P<0.05) and on tiller numbers and total biomass (P<0.05). E- A. inebrians had no significant effects on seed germination, seedling growth, tiller height, tiller number or total biomass (P>0.05). S. capillata and P. sphondylodes had no significant effects on A. inebrians. In summary, E+ A. inebrians showed significant antagonism to S. capillata and P. sphondylodes, but E- A. inebrians had no significant effects on the other two grasses.

The study of soil microbial biomass and soil enzyme avtivity on different grassland in Hulunbeier, Inner Mongolia

WENDU Ri-le, LI Gang, ZHANG Jing-ni, LAI Xin, YI Jin, FAN Guo-yan, YANG Dian-lin

2010, 19(5):  94-102. 

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In this study, 5 different types of grassland (Filifolium sibiricum steppe, Stipa baicalensis steppe, Leymus chinensis steppe, Stipa grandis steppe, Stipa kryrowi steppe) in Hulunbeier were selected as the research object to analyze the variation of the soil physicochemical characteristics, soil microorganism, soil microbial biomass, soil enzyme activity and the inter-relationship among them. The results showed that the number of microorganisms in different types of grassland were in the same changing trends: bacteria>actinomycetes>fungi, but the number of each microorganism and composition reduced significantly (P<0.05). The bacteria number in 5 different types of glasslands was L. chinensis steppe>S. baicalensis steppe>S. kryrowi steppe>F. sibiricum steppe>S. grandis steppe, the fungi number was S. kryrowi steppe>L. chinensis steppe>F. sibiricum steppe>S. baicalensis steppe>S. grandis steppe, the actinomycetes number was F. sibiricum steppe>S. kryrowi steppe>L. chinensis steppe>S. baicalensis steppe>S. grandis steppe. Soil microbial biomass C, N (SMBC, SMBN) reduced significantly (P<0.05) in different grasslands. The microbial biomass carbon and nitrogen in F. sibiricum steppe soil were significantly higher than others (P<0.05), soil microbial biomass C and N in S. grandis steppe and L. chinensis steppe were lower. Results also showed that soil activitiey reduced significantly (P<0.05) in different grasslands with 0-10 cm higher than 0-20 cm in the vertical distribution. Soil activitoes of catalase and invertase activities of F. sibiricum steppe were significantliy higher than S. grandis steppe, S. baicalensis steppe; Soil urease activity of S. kryrowi steppe was the highest and significantly different from S. grandis steppe, F. sibiricum steppe, soil phosphatase activity in L. chinensis steppe was the highest and significantly different from others. Correlation analysis indicated that soil microbe quantity, soil microbial biomass, soil enzyme activity and soil physicochemical characteristics in different grasslands had different degrees of correlation. The regression formula indicated that soil microbial biomass C increased with soil moisture, bacteria quantity but decreased with soil phosphatase activity; soil microbial biomass N increased with soil hydrogen peroxidase activities, but decreased with soil phosphatase activity and soil bulk.

Modeling the evapotranspiration of an alpine meadow ecosystem in the northern Tibet Plateau based on MODIS images

FU Gang, SHEN Zhen-xi, ZHANG Xian-zhou, WU Jian-shuang, SHI Pei-li

2010, 19(5):  103-112. 

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Evapotranspiration (ET) is an important component of the hydrologic budget in alpine meadow ecosystems of the Tibet Plateau. The water use efficiency (WUE_EC) at the ecosystem level was used to model ET. Simple linear correlation analysis and multiple stepwise linear regression analysis showed that normalized difference vegetation indices (NDVI), relative air humidity (Ha), and heat flux (H) could play important roles on the WUE_EC. We related WUE_EC with NDVI, Ha, and H, separately (there were significant discrepancies in water use efficiency modeled by H, WUE_H, and WUE_EC). We modeled evapotranspiration at the ecosystem scale with the multiple stepwise linear regression equations of water use efficiency (WUE) and estimated gross primary production (GPP_VPM) by a vegetation photosynthesis model (VPM). The simple linear regression equations between modeled evapotranspiration, ET_NDVI, ET_Ha, and observed evapotranspiration from eddy covariance of ET_EC, ET_NDVI=1.298 5ET_EC (R²=0.802 9, n=46, P<0.000 1) and ET_Ha=1.311 8ET_EC (R²=0.748 7, n=46, P<0.000 1), individually, showed some discrepancies in modeled evapotranspiration and ET_EC. We quantitatively analyzed these discrepancies. The differences between ET_EC and ET_NDVI were chiefly attributable to photosynthetic active radiation (PAR) and GPP_VPM, while the differences between ET_EC and ET_Ha were mainly attributed to PAR, GPP_VPM, and enhanced vegetation indices (EVI).

Effects of four gramineous pasture grasses on soil physicochemical properties in wasteland at the buffer zone of Guanting Reservoir

XIAO Bo, WU Ju-ying, WANG Qing-hai, YAO Shui-hong

2010, 19(5):  113. 

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Four gramineous pasture grasses (Festuca arundinacea, Elymus sibiricus, Bromus inermis and Bromus riparius) were planted in representative wasteland of the buffer zone of Guanting reservoir. After 2 years, the surface soils (0-30 cm) were sampled and analyzed to explore the effects of pasture grasses on soil physicochemical properties. The four pasture grasses grew well on the wasteland and produced 10.99 t/ha dry forage a year which can be used to feed livestock. The physicochemical properties of the wasteland soil were considerably improved by the physical, chemical and biological effects of the pasture grasses, but the effects were not significant between them. In terms of physical properties, the clay was significantly increased by 14% silt was significantly reduced by 21%, the soil water-stable aggregates with particle size>0.25 mm increased by 112%, the bulk density was significantly reduced by 15% and soil porosity was also considerably improved. In terms of chemical properties, soil organic matter was significantly increased by 227%, total nitrogen by 76%, and total phosphorus, available nitrogen and available phosphorous were increased by 66%, 41%, and 4%, respectively. We conclude that planting the four gramineous pasture grasses on the wasteland will generate both significant ecological and some economic benefits. This pattern may be a possible solution for the remediation and utilization of wasteland in northern China.

An investigation of nutrition components and types in Tibet main crop straws and pastures

QIN Yu, LI Xiao-zhong, JIANG Wen-qing, TIAN Fa-yi,
ZHOU Zhi-yu, WANG Nan, WANG Tao

2010, 19(5):  122-121. 

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The nutrition contents of crop straws and seeds (the main source of roughage and concentrate respectively) for livestock as well as 57 kinds of natural grassland and cultivated herbage from Xigaze and Shannan region were analyzed. The nutritive types of crop straw were carbon and carbon-nitrogen types with low crude protein (CP) and Ash (ASH) content, but high crude fiber (CF), neutral detergent fiber (NDF)and acid detergent fiber(ADF). For crop seeds, the nutrition value of rapeseed meal and peas were both higher than hull-less barley. However, the nutritive types of Gramineae and Leguminosae were nitrogen and nitrogen-carbon types with high CP content and low CF. There were 13 kinds of Graminaceous forage species with a CP content more than 20%, and in one acid-resistant grass (Bromus pumpellianus) it was up to 30.72%. Nine kinds of legume were studied. The CP content of chickpea (Cicer arietinum) was up to 27.46%, but CF was only 18.91%, and ASH was 9.30%. French spinach (Spinacia oleracea), one of the Chenopodiaceae, was an Ash-nitrogen nutritive type with a crude protein content of 20.17%, ASH of 20.15%, and CF of only 12.67%. The CF contents of these 22 pastures were less than 30%, nevertheless the ASH content ranged from 6.24% to 10.43%.

Genetic diversity in white clover germplasm detected by SRAP markers

ZHANG Jing-yuan, PENG Yan, LUO Yan, MA Xiao

2010, 19(5):  130-138. 

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SRAP (sequence-related amplified polymorphism) markers were used to analyze genetic diversity of 41 white clover (Trifolium repens) accessions using 20 pairs of random primers. The results were: 1) The primer pairs amplified 479 clear bands, including 411 polymorphic bands, which ranged from 13 to 44 bands per primer pair with an average of 23.95 bands. The percent of polymorphic loci was 85.16%, and the polymorphism information content ranged from 0.182 to 0.334 with an average of 0.268, which showed that the tested white clover had a rich genetic diversity of germplasm. 2) Genetic similarity ranged from 0.586 6 to 0.989 6 among all accessions with an average of 0.730 7, which also suggested that there was a rich genetic variation among the white clover germplasms. 3) Cluster analysis and principal component analysis of 41 white clover accessions divided them into 3 groups on the genetic similarity of 0.71 and most of the accessions from the same or similar ecologic geographical environment clustered in one group, showing a certain degree of eco-geographical distribution.

Genetic diversity of Cichorium intybus germplasm resources using sequence-related amplified polymorphism (SRAP) molecular markers

LUO Yan, BAI Shi-qie, PENG Yan, ZHANG Yu, MA Xiao

2010, 19(5):  139-147. 

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Genetic diversity of 48 accessions of all Cichorium intybus collected from 5 geographical groups was analyzed using sequence-related amplified polymorphism (SRAP) molecular markers with 28 SRAP primer pairs. 1) A total of 333 alleles were detected at 28 loci, an average of 11.89. Occurrence of polymorphic sites (P) was 95.09% and the polymorphic information content (PIC) ranged from 0.23(me3+em3)to 0.44(me1+em10), an average of 0.33. 2) The genetic similarity (GS) among all accessions ranged from 0.55 to 0.89 with an average of 0.69. For all geographical groups, the GS value ranged from 0.63 to 0.96. Among these groups, a high genetic diversity was observed in groups from the Netherlands (P, 95.52%) and Italy (P, 95.38%). These results suggested that there was a high genetic diversity among all C. intybus accessions tested. 3) Based on cluster and principal component analyses, 48 accessions could be divided into five groups by the nearest phylogenetic relationship, and the five groups reflected the five geographical origins.

Characteristics of amino acid constituents of cultivated forages in Tibet province

JIANG Wen-qing, ZHOU Zhi-yu,QIN Yu, WANG Nan,WANG Tao,LI Xiao-zhong,TIAN Fa-yi

2010, 19(5):  148-155. 

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The characteristics of total amino acid (TAA), essential amino acids (EAA), sulfur amino acid, and limited amino acid of 57 cultivated forages in Tibet were studied. The TAA content ranged from 6.11% to 23.71% and declined in the sequence Leguminosae>Chenopodiaceae>Gramineae. The average content of EAA was 6.42% and the highest and the lowest ratios of EAA to TAA content were in the Leguminosae and Gramineae, respectively. The sulfur amino acid content ranged from 0.44% to 1.63%, and varied greatly between species. There was also a high ratio of limited amino acid content, which ranged from 0.63% to 2.25%. There were 47 species, accounting for 82% of all the forages, with ratios of EAA/NEAA>60% and of EAA/TAA>40%. This showed that there was a reasonable constitutive ratio of amino acid and high nutritive value in the cultivated forages, which were therefore excellent feed resources for local livestock.

Effects of potassium fertiliser on potassium content in flue-cured tobacco leaves and the economic benefits in Gansu province

HU Juan, QIU Hui-zhen, HE Xiu-cheng, ZHANG Wen-ming,
LI Ya-juan, ZHANG Chun-hong

2010, 19(5):  156-160. 

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Low potassium (K) content in flue-cured tobacco leaves and the low economic benefits of flue-cured tobacco have been a big problem in tobacco production because of inadequate fertilization in Gansu province. The effects of different K rates on K content in flue-cured tobacco leaves and the subsequent economic benefits were studied in a field trial in Zhengning county, Qingyang city, Gansu province in 2007. The four K rates were 0, 90, 180, and 270 K₂O kg/ha (treatments K0, K1, K2 and K3). The K content in flue-cured tobacco leaves increased with K fertilization rates and reached a peak at the rate of 270 K₂O kg/ha. The response of K content in leaves to K application differed with leaf position, and the most sensitive response was in the middle leaves. K fertilizer application had significant effects on the order of K content in upper, middle, and bottom leaves, which changed in K1, K2, and K3 treatments compared with K0. The flue-cured tobacco yield, average price, ratio of mid-high grade leaves, output value, and other economic benefit parameters were all increased with increased K fertilizer rate. Therefore increased K fertilizer application could increase economic benefits of flue-cured tobacco by enhancing yield and improving quality. In this field trial, the best K application rate was at least 270 K₂O kg/ha.

Seasonal variation of ground dwelling arthropod communities in an arid desert of the middle Heihe River basin

LIU Ji-liang, LI Feng-rui, LIU Qi-jun, NIU Rui-xu

2010, 19(5):  161-169. 

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Arthropod is one of the important components of dry desert ecosystems and plays a key role in maintaining ecosystem structure and functioning. Up to now, relatively fewer studies have explored seasonal variation in arthropod community composition and diversity of arid desert ecosystems in the Heihe River basin, North-west China. We investigated the composition and diversity of arthropod communities using pitfall trapping method in both early June and mid September in a typical arid desert of the middle Heihe River basin. Main findings of our study are as follows. 1) Tenebrionidae was a key group of the ground dwelling arthropod communities in this arid desert ecosystem. 2) Analysis of NMDS (non-metric multidimensional scaling) indicates significant between-season variation in the abundance, biomass, functional groups of the arthropod communities, which is mainly reflected in the following three aspects. First, the total individuals, total biomass and overall richness are significantly higher in spring than in autumn. Second, Tenebrionidae belonging to detritivores, Oedipodidea and Lygaeidae belonging to Phytophages, and Nesticidae belonging to Predators occurred mainly in spring, whereas Formicidae belonging to Omnivores, Thomisidae and Carabidae belonging to Predator and Curculionidae belonging to Phytophage occurred mainly in autumn. Thirdly, the ratio of predators to detritivores and omnivores in the arthropod communities in the early June census was found to be much higher than that in the mid September census.

Responses of aboveground net primary production and population structure of Caragana microphylla to prescribed burning in a typical steppe of Inner Mongolia

LIN Yan, BAI Yong-fei

2010, 19(5):  170-178. 

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The density and cover of the native shrub species Caragana microphylla, has greatly increased in recent decades in the Xilin River basin of Inner Mongolia, in areas previously dominated by Leymus chinensis and Stipa grandis. We conducted a field experiment of one- and two-years burning in a typical successional steppe dominated by C. microphylla. Our main objective was to determine whether and how the prescribed burning can be used as a management tool for controlling shrub encroachment of the Inner Mongolia grasslands. The effects of prescribed burning on morphological traits, aboveground biomass, and biomass allocation of C. microphylla were examined. Pretreatment measurements were made in 2005 and the first prescribed burning was in 2006 with the second repeat burning in 2007. Results showed that: 1) C. microphylla may have been an expanding population in our experimental plots. Of the 6,588 individual shrubs examined, 30% were small-crown size shrubs (0-50 cm), 49% were mid-crown size shrubs (50-150 cm), and only 21% were large crown size shrubs (>150 cm); 2) At the plant community level, growth of C. microphylla was significantly inhibited by prescribed burning. The aboveground net primary productivity (ANPP) of C. microphylla was reduced by 27% for 1-year burning and by 66% for the 2-year repeat burning, compared with the initial ANPP before treatment; 3) Burning significantly enhanced the current year stem density of C. microphylla, increased biomass allocation to new stems, reduced biomass allocation to leaves, and shifted stem/leaf ratios from 1∶4.4 to 1∶1.1; 4) At the individual bunch level, the impact of burning on aboveground biomass production of C. microphylla varied with crown size. The largest reduction in aboveground biomass was found in the small-crown size class, in which the average aboveground biomass decreased by 57% for the 1-year burning and by 60% for the 2-year repeat burning. Results from this study suggest that prescribed burning is an effective approach for controlling the growth and encroachment of C. microphylla into the Inner Mongolia grasslands.

The main forage succession and ground surface characteristic changes during degradation and restoration of alpine Kobresia meadow

LI Yi-kang, LIN Li, ZHANG Fa-wei, LIANG Dong-ying,WANG Xi, CAO Guang-min

2010, 19(5):  179-185. 

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The change of soil surface characteristics during degradation and restoration of alpine Kobresia meadow was followed together with the important value changes of Kobresia pygmaea, K. humilis and Gramineae and of their patch dispersal. During degradation, the value of K. pygmaea was significantly more important than that of K. humilis and Gramineae(P＜0.05). In a transect, the coverage of K. humilis was rapidly reduced, the coverage of black patch increased to nearly double, and patches of K. pygmaea were widely dispersed. K. pygmaea is the dominant species in seriously grazed K. pygmaea meadow, and its importance is significantly higher than that of K. humilis and Gramineae(P＜0.05), the coverage of black patch increased, then collapsed. The emergency ratio of K. humilis patch is little. In the course of restoration, the importance of Gramineae increased, K. humilis was not common, and in the restoration patch, Gramineae became the dominant species while K. pygmaea nearly disappeared and the coverage of black patch and bald patch shrunk, but plant coverage increased. Gramineae became the dominant species in the better restoration meadow, and the importance of K. pygmaea and K. humilis decreased: there was no black patch or bald patch. Alpine meadow degradation resulted in a succession of dominant species, but black patch and bald patch were universal. Fencing and light grazing measures can effectively restore degraded meadows.

Temporal and spatial distribution characteristics of aboveground biomass of grassland plant communities in an arid area

LI Wei-hong, ZHOU Hong-hua, YANG Xiao-ming, DING Hui

2010, 19(5):  186-195. 

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The temporal and spatial distribution characteristics of the aboveground biomass of the main constructive species of grassland plant communities in the lower Tarim River and their response to groundwater depth and chemical composition of groundwater were analyzed. The results showed that: 1) The highest aboveground biomass of grassland plant communities was in 2005 (up to 741.75 g/m²); Aboveground biomass in grassland plant communities diminished with increasing vertical distance from the river. 2) There was a significantly linear relationship between diversity indices and aboveground biomass. 3) Aboveground biomass of grassland plant communities was highest when the groundwater depth was less than 3 m. The upper limit of salt-tolerance of grassland plant communities sensitive to Mg-Cl salt, was about 5.0 g/L.

Effects of irrigation on grain yield and water use efficiency of winter wheat

HUANG Cai-xia, CHAI Shou-xi, ZHAO De-ming, LI Zhi-xian, CHANG Lei, WANG Ting

2010, 19(5):  196-203. 

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The effects of irrigation on grain yield and water use efficiency of the winter wheat, Lingkang-2 were investigated. Five experimental treatments were designed on the basis of different irrigation amounts during the whole growing period. The soil available water content (AWC) changed with different growth stages, with a smaller value (2.37 mm) at the raising stage and larger one (9.88 mm) at the jointing stage, and with the maturity stage (2.54 mm) in between. The latter stage even had negative values in the 0-60 cm soil layers at maturity for W1 and W2. The milking stage was significantly different for all treatments. The maximum daily consumption of water was at heading-flowering and sowing-reviving, which showed that pre-winter irrigation contributes to improved emergence rates and promotes growth of winter wheat. W3 had the highest grain yield (6 296.52 kg/ha), grain weight (53.12 g) and ears per unit area (61.83 Spike×10⁴/ha) while water use efficiency (WUE) and irrigation water use efficiency (IWUE) were lower. However, compared with W3, W4 had the higher WUE and IWUE, and its grain yield was a little lower, at 6 240.37 kg/ha. Correlation analysis showed that there were highly significant positive correlations between yield and grain weight (R=0.99^**), WUE (R=0.97^**), at flowering-maturity (CA_m) (R=0.88^*), and total growth (CA_t) (R=0.88^*), indicating that water stress at the late growth stage accelerated the aging process of winter wheat, shortened the grain filling period, reduced grain weight, and eventually led to decline of grain yield. Considering the impact of different irrigation treatments on grain yield and water use efficiency of winter wheat, the W4 treatment was the most important.

Effects of irrigation quota on yield and quality of summer-sown, naked oat

WU Na, BU Hong-zhen, ZENG Zhao-hai, REN Chang-zhong, HU Yue-gao

2010, 19(5):  204-209. 

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Randomized block field experiments were conducted to determine the effects of irrigation quota on grain yield, quality, mineral element contents, and forage quality of naked oat (Avena sativa). The highest grain yield was achieved with an irrigation quota of 150 mm under drip irrigation (W4), followed by W5, CK, W3, W2, W1. The main yield components were reduced to certain extent with less irrigation (treatments W1, W2, and W3). Grains per spike and spike numbers/ha were significantly reduced, and led to a significant reduction in yield. The best grain quality was obtained with an irrigation quota of 120 mm under drip irrigation conditions (W3). Compared with the traditional irrigation treatment (CK), crude protein, crude fat, and β-glucan content in W3 were increased by 4.53%, 8.58% and 23.10% respectively (P<0.05). Potassium, zinc, iron, copper, and manganese levels of grains under W3 treatment were significantly higher than those of the traditional irrigation (CK), but calcium and magnesium contents were not significantly different. The W3 treatment had better forage quality. Additionally, the digestible dry matter and relative feeding value of W3 were 3.37% and 9.28% higher than those of the CK (P<0.05).

A study on morphological variations of Cynodon dactylon in south China

HUANG Chun-qiong, ZHOU Shao-yun, LIU Guo-dao, BAI Chang-jun

2010, 19(5):  210-217. 

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Eleven morphological characteristics of 36 accessions of wild Cynodon dactylon from south China were observed and analyzed. The results showed that: 1) Abundant morphological variation existed in accessions of C. dactylon. Their coefficients of variation were ranked as follows: leaf hairs (129.78%)>turf height (38.18%)>leaf length (37.61%)>turf density (32.41%)>internode length (21.80%)>inflorescence length (18.44%)>spikelet number (15.08%)>internode diameter(14.49%)>leaf width (14.05%)>inflorescence branch number (9.45%)>leaf color (7.64%). 2) Morphological characteristics of C. dactylon had significant relationships. Those with high turf had lighter color, more leaf hairs, longer and wider leaves, stronger stems, longer inflorescence, and more inflorescence branches and spikelets, whereas those with low turf had the opposite characteristics. 3) With higher latitudes, C. dactylon had darker leaf color, stronger stems, fewer inflorescence branches and spikelets. It also became stronger, with higher turf, longer inflorescences but fewer spikelets as the longitude increased. 4) Based on eleven morphological characteristics, accessions of wild C. dactylon from south China were clustered into three morphological types.

A study on soil biological properties of artificial grassland over different cultivation times in Bayanbulak

YIN Wei, HU Yu-kun, LIU Yan-Yan, GONG Yan-ming, ZHANG Wei,
LIU Wei, ADELIET·Abeutalipu

2010, 19(5):  218-226. 

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The artificial grassland in Bayanbulak was used as an example to examine the relationship between soil microorganism numbers, enzyme activities, and soil factors over different lengths, 0(CK), 4, 8, 15 and 20 years of cultivation. The numbers of soil microorganisms increased initially, reached maximum at 4 years, and then decreased with time. The order of microbial numbers in all grasslands was bacteria＞actinomycete＞fungi. The numbers of soil microorganisms in the 0-20 cm soil layer was higher than that in the 20-40 cm layer. Soil microbes reached their maximum and minimum in August and September, respectively. The order of soil catalyse activities was the same as that of microbe numbers, but the order of soil urease activity was 4＞8＞0＞20＞15 years. However, the two enzyme activities were higher in the 0-20 cm soil layer than those in the 20-40 cm layer. Stepwise regression showed that the numbers of soil microorganisms, soil urease activity, and catalase activity were mainly affected by available nitrogen and by urease activity, total phosphorus and soil organic matter, total phosphorus and pH value, respectively.

The present situation of grassland and plant diversity in Sunan and Subei county

ZHAO Zhong, HE Yi, LI Qing, YANG Peng-yi, JIN Ci-fu, YANG Xue-lan,
SUN Xiao-yun, GU Zi-lin, ZHANG Wei-jun, WANG Jun, QU Yong,
CHAI Yong-qing, ZE De, NA Bater

2010, 19(5):  227-238. 

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Investigation on grassland sorts and grassland plant resource was carried out in Sunan Yuguor and Subei Mongolian Autonomous County, Gansu province in 2007-2008. 226 grass quadrates, 125 shrub quadrates, and 32 mixture quadrates were tested; 22 500 km² of investigation area were labeled on the topographic map. The investigation route was 185 000 km. According to the “Chinese Grassland Divisional Criteria and Chinese Grassland Classification System”, It was sure that the grassland in Sunan county embraced 29 types of 24 forms belonged to 18 subclasses in 9 classes, respectively; and the grassland in Subei county were 29 types of 19 forms from 17 subclasses in 9 classes. 986 plant samples of 381 species from 176 genera of 53 families were collected. Among the plants, 300 species were forage grass. The general situation of grassland in Sunan and Subei counties was degradation. Partial area is preserved well; beside climate factor, overgrazing is the key cause that induced the grassland degradation; the next reason is the rodent damage. Grasshopper is not the cause bringing grassland degradation. The species diversity of grassland plant in the investigation area has not been destroyed greatly. However, the species dominance in the plant community had a large variation, which shows that the change of species relation in the community has already taken place. The biodiversity is suffering threat.

The spatial distribution patterns of rare plant Gymnocarpos przewalskii communities in Subei

CHAI Yong-qing, CAO Zhi-zhong, CAI Zhuo-shan, WAN Li-xia, LI Xue-ling

2010, 19(5):  239-249. 

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In order to explore the spatial patterns of Gymnocarpos przewalskii in the Subei desert, as well as its causes and maintenance mechanisms, 60 quadrats are randomly set according to the vegetation types, the topography, geomorphology and the different altitudes. The variance/mean ratio, parameter of negative binominal, dispersal index, index of clumping, index of mean crowding, index of aggregation and index of patchiness, poisson distribution method are used to analyze the spatial distribution patterns and Kolmogogorov-Smirnov test for significance test. The results show that the population distributions of the G. przewalskii are contagious distribution at the dry beds of Gangou and One tree; taking on random distribution at the foreland dry bed areas of Lucaogou and Gangoukouzi, which is due to intense competition between middle-old plants against the background of their sexual reproductive decline and lack of seedlings; The intermediate type between random and contagious distribution at Yema River, which is due to the combined affect of intraspecies and interspecific competition, and the scouring of forceful deluge and mud-rock flow, coming close to contagious distribution at Jinmiaojing in Mazong mountain area, the reason of contagious distribution was related with its ecosystem environment. The seeds of G. przewalskii silted gradually in this area with eroding by flood and filling by silt because of which lies in puluvial fan plain. All of this caused the contagious distridution of G. przewalskii in the area.From the altitude standpoint, the population distributions of the G. przewalskii is weak contagious distribution at 1 500-1 550 m, random distribution at 2 400-2 450 and 2 450-2 500 m where mostly living from the Subei desert; the intermediate type between random and at 2 700-2 750 m. The spatial patterns of G. przewalskii in the Subei desert result from the major affect of its propagation characteristics and natural disaster, together with other factors, such as Human activity and environmental factors.

Impact assessment of laws and policies on biodiversity and grassland biodiversity

YAN Wei-hong, XU Zhu, WANG Yu-qing, LIU Jian-li, XIAO Hai-jun, SHAN Gui-lian

2010, 19(5):  250-259. 

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Biodiversity-related documents, including international and domestic laws, regulations and policies, have been listed systematically, for study and analysis. The development process and problems of biodiversity-related laws and regulations are discussed; the international principles, direction and essence of biodiversity protection are in-depth and clearly understood. The development status and existing problems of laws and regulations on the conservation of biodiversity, especially grassland biodiversity conservation in China are presented. Ideas for developing Chinese specific, national conditions, were drawn from the experiences in the United States, the European Union, and India. The ideas are explored as a basis for the principles of Chinese enactment of laws and regulations for biodiversity conservation and several suggestions for formulation of laws and policies on Chinese biodiversity conservation are offered.

Advancement in the research of salt-alkali tolerance genes in alkaligrass

REN Wei, WANG Zhi-feng, XU An-kai

2010, 19(5):  260-266. 

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Cloning functional salt-alkali tolerance genes of halophytes plant is the key for understanding the molecular mechanism of plant salt-alkali tolerance, and breeding new salt-alkali tolerant plants. Alkaligrass (Puccinellia), as a excellent pasture and valuable halophytes germplasm, provides us with a wealth of salt-alkali tolerance genes. By cloning the salt-alkali stress-induced genes of Alkaligrass, and analyzing their structure, function and expression, we not only possibly breed new salt-alkali tolerance GM plants, but also provie theory support for the improvement of saline soil. So, the present paper summarizes the advancement in the research on salt-alkali tolerance genes.

Rainfall interception and stemflow for Caragana microphlla in Horqin Sandy Land, northern China

LI Yan-qing, ZHANG Tong-hui, ZHAO Xue-yong, LIU Xin-ping,
TONG Xun-zhang, YUN Jian-ying

2010, 19(5):  267-272. 

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From June to Sepetember 2009, a typical shrub, Caragana microphlla, commonly used to stabilise sand dunes, was selected from Horqin Sandy Land to investigate rainfall redistribution. During the entire experiment, the cumulative amount of rainfall was 103.1 mm. The amount of throughfall (TF) was 73.1 mm (70.9% of the total rainfall), of stemflow (SF) was 4.1 mm (4.0%), and of interception (I) was 25.8 mm (25.1%). Regression analysis showed a significant positive linear correlation between rainfall and TF, SF, and I. The correlation between rainfall and TF% is well represented by an exponential function as is I%. Furthermore, TF% was an exponential function of the rain intensity in 1 hour (I_h), but for I% was a power function of I_h in this experiment.

Genetic analysis and mapping with SSR markers of the brown midrib gene bmr-6 in Sorghum bicolor

LI Jie-qin, WANG Li-hua, ZHAN Qiu-wen, FAN Jun-cheng

2010, 19(5):  273-277. 

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The mutants, which produced brown leaf midribs, reduced the content of lignin by 40% to 60% compared with normal varieties. This low lignin content largely promoted the rate of digestion in livestock. The F₂ population was constructed from the hybrid of N592 (bmr-6) and Sa (white midrib) to map the bmr-6 gene. The ratio of white and brown midribs was 3 to 1 in the F₂ population. Therefore, the bmr-6 gene is a single recessive gene. Using 171 SSR markers and F₂ recessive population, one SSR (simple sequence repeats) marker (txp295) that linked with the bmr-6 gene was detected and the genetic distance was 4.2 cM. In addition, the bmr-6 gene was mapped to the seventh linkage group of sorghum because the txp295 marker was located on this linkage group.

Changes in protective enzyme activities in cells of Hemarthria compressa under water stress

GUI Shi-chang, YANG Feng, ZHANG Bao-yi, ZHANG Xin-quan,
HUANG Lin-kai, MA Xiao

2010, 19(5):  278-282. 

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Two national varieties “Guangyi” and “Chonggao” were used to study the changes of superoxide dismutase (SOD), peroxidase isoenzyme (POD), catalase (CAT) and malondialdehyde (MDA) in roots. The results showed that the MDA content and the activities of superoxide dismutase, peroxidase isoenzyme, and catalase in the roots increased during water stress, with a peak at 14 days. After that, the content of malondialdehyde and the activities of the three kinds of protective enzymes declined significantly. The study also showed that the initial rise in the content of malondialdehyde was mainly caused by drought stress. However, the rises in the three kinds of protective enzymes activities may result from the rise of malondialdehyde. After 14 days of drought stress, the reduction in content of the three protective enzymes may due to their tolerance and adaptability after experiencing the drought-threshold period. During the study, the roots of “Chonggao” always had a higher MDA than “Guangyi”. Based on the drooping and wilting status of the two grasses, we conclude that “Guangyi” has a greater drought resistance than “Chonggao”.

Effects of mixed application of fertilizers and herbicides on production performance of Elymus sibiricus

YOU Ming-hong, LIU Jin-ping, BAI Shi-qie, ZHANG Xin-quan, BIAN Zhi-gao

2010, 19(5):  283-286. 

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Six types of treatment with different contents of (NH₂)₂CO, KH₂PO₄ and broad-leaved herbicide 75% tribenuron dry suspension concentrate (SC) and 28% wettable powder sulphinpyrazone (WP T-Y) were applied to Elymus sibiricus cv. chuancao NO.2 grassland at the jointing stage. The mixed treatment affected weed species, weed biomass per unit area, and weed rate to total biomass. Three treatments, 7 500 g/ha (NH₂)₂CO+300 g/ha KH₂PO₄+27 g/ha 75% tribenuron dry SC, 7 500 g/ha (NH₂)₂CO+27 g/ha 75% tribenuron dry SC, and 15 000 g/ha (NH₂)₂CO+300 g/ha KH₂PO₄+75 g/ha 28% WP T-Y significantly improved the vegetative growth, and resulted in coefficients of variation of 12.42% (P=0.000 6), 29.98% (P<0.000 1), 25.93% (P<0.000 1) for height, fresh forage yield and hay yield, respectively. The other three treatments, 7 500 g/ha (NH₂)₂CO+300 g/ha KH₂PO₄+27 g/ha 75% tribenuron dry SC, 7 500 g/ha (NH₂)₂CO+75 g/ha 28% WP T-Y, and 15 000 g/ha (NH₂)₂CO+300 g/ha KH₂PO₄+75 g/ha 28% WP T-Y, significantly (P=0.000 9) increased seed yield of E. sibiricus. However, the correlation coefficients of these mixed treatments with production performance were low, which may be due to the interaction of fertilizer and herbicides. Overall, the mixed application of fertilizer and herbicides is worth applying widely, because of the reduced number of field operations and management costs, and the dual effect of fertilization and weed control achieved.