Table of Content

20 October 2009, Volume 18 Issue 5

Previous Issue    Next Issue

Promoting prataculture development in arable region to ameliorate the farming system and insure food security in China

REN Ji-zhou, LIN Hui-long

2009, 18(5):  1-9. 

Asbtract ( 1082 )   PDF (1315KB) ( 1504 )  

References | Related Articles | Metrics

Considering the relations among cropland, grain yield and population in China, the country’s food security faces a formidable challenge. Although China will have no problem to support its population which demanding about 200 million ton grain in the medium and long terms, the huge amount of food demanded by livestock, about 500 million tons, will be a unbearable load for its traditional agricultural system. It would be unreliable to rely on the international market due to its limited capacity and uneven price. To secure its food safety, China has to reform its food structure by stressing equally on both animal and plant products, adjusting the structure of new food production and consumption, which is a long term strategy to deal with the situation of world food shortage. To develop prataculture in arable land is an effective approach to integrate forage growing into the traditional farming region so that to maintain and increase grain production by fully utilizing all recourses such as solar rays, heat, water, soil and at the same time to develop herbivore livestock production. This approach may have important functions in terms of ecological service and great potential role to play since there is a huge land resource available. It would be a significant measurement taken in securing the food safety and may be regarded as a revolution to the current model of farming system.

Effects of ferrous ion in an acid environment on early growth and physiology of Medicago sativa WL525

LI Jian-feng, SHI Shang-li, ZHANG Shu-qing

2009, 18(5):  10-17. 

Asbtract ( 607 )   PDF (1350KB) ( 491 )  

References | Related Articles | Metrics

The effects of Fe²⁺ in acid soil on seeding growth and physiological index of M. sativa were studied in sand culture. M. sativa grew very well at Fe²⁺ concentrations of 10－100 mg/kg. The morphological items measured were rate of germination, plant height, leaf area, number of leaves per plant, and weight of shoots and roots. no less than the control group (pH 6,Fe²⁺ 10 mg/kg); Seedling growth was stimulated, and the physiological index of plants was higher, or significantly (P<0.05) higher than that of other treatments when the concentration of Fe²⁺ was less than 50 mg/kg. Concentrations of Fe²⁺ in the range 100－200 mg/kg soil resulted in a seriously restricted growth of M. sativa and there was a significant (P<0.05) decrease in the measured morphological items. There were significant (P<0.05) differences in electrolyte leakage, MDA content, root activity, soluble sugar content, Fv/Fo and Fv/Fm with different concentrations of Fe²⁺; When the concentration of Fe²⁺ was less than 100 mg/kg, the root activity, electrolyte leakage, Fv/Fo and Fv/F were significantly (P<0.05) higher than those in Fe²⁺ concentrations of 100－250 mg/kg. Chlorophyll content was not correlated with Fe²⁺ concentration.

Evaluation of drought resistance and analysis of physiological index variation for different Chinese Iris populations

MENG Lin, MAO Pei-chun, ZHANG Guo-fang

2009, 18(5):  18-24. 

Asbtract ( 667 )   PDF (831KB) ( 582 )  

References | Related Articles | Metrics

The drought resistance of 15 germplasms of Iris lactea var chinensis from different populations in northern China at the seedling stage was comprehensively identified and evaluated in a green house using the simulated drought stress and rewatering method. The relative electrical conductivity rate (REC), content of malondialdehyde(MDA), free proline accumulation (Pro), relative water content of leaves (RWC), SPAD value of chlorophyll, and relative growth rates (RGR) were measured at 0, 5, 10, 15, 20 and 25 d of drought stress and at 5 d after rewatering. Three drought resistant classes (high drought resistance (HDR), medium drought resistance (MDR), and weak drought resistance (WDR)) were classified using the maximum distance cluster method, and the variation trends and rules of physiological indexes were analyzed. The REC, Pro, and MDA of three different drought resistant classes showed a gradual increasing trend in the order HDR<MDR<WDR. The REC showed no significant difference between the three drought resistant classes before stress day 20, but there was a significant (P<0.05) difference at 25 d. There was no significant difference in Pro or MDA between the three drought resistant classes before stress day 15, but there was a significant (P<0.05) difference at days 20 and 25. The SPAD value of chlorophyll and RWC showed gradual decreasing trends in the order HDR<MDR<WDR. The SPAD value and RWC had significant differences at days 20 and 25 between the three drought resistant classes. The physiological indexes recovered to different degrees after rewatering.

Effects of saline-sodic stress on the photosynthesis rate, transpiration rate and water use efficiency of Leymus chinensis

HUANG Li-hua, LIANG Zheng-wei, MA Hong-yuan

2009, 18(5):  25-30. 

Asbtract ( 826 )   PDF (990KB) ( 765 )  

References | Related Articles | Metrics

Changes of photosynthetic rate (Pn), transpiration rate (Tr) and water use efficiency (WUE) of L. chinensis were investigated under different saline-sodic stress conditions by culturing in soils of five pH values. Pn, Tr, Gs and VpdL increased and Ci decreased with increased simulated photosynthetic radiation, while the WUE first increased, then decreased. Under the same simulated photosynthetic radiation, Pn and Tr decreased and WUE increased as saline-sodic stress increased. For example, when the simulated photosynthetic radiation was 1 500 μmol/m²·s, Pn and Tr of L. chinensis growing at pH 9.78 saline-sodic stress were reduced 43.8% and 51.3% respectively compared with those of the CK (pH 7.15). Under saline-sodic stress, L. chinensis has a higher water use efficiency (WUE) since Tr is reduced more than Pn. This could be an important physiological mechanism of saline-sodic tolerance of L. chinensis.

Field measurements of meadow surface emissivity spectra at the Xilinhaote grassland of China

ZHANG Yong, YANG Hu, ZHENG Zhao-jun, ZHANG Li-jun, LU Qi-feng,
LI Gui-cai, YANG Zhong-don

2009, 18(5):  31-39. 

Asbtract ( 879 )   PDF (1443KB) ( 543 )  

References | Related Articles | Metrics

The meadow surface emissivita spectra of the Xilinhaote grassland of China is one of the key factors for calibration of thermal infrared remote sensors using land surface. Based on the iterative spectrally smooth temperature/emissivity separation (ISSTES) algorithm, Xilinhaote meadow surface emissivity spectra were measured using a BOMEM MR154 Fourier transform spectroradiometer and infrared golden board. Emissivity spectra data were obtained at different times and land surface conditions. With these measured emissivity spectra, all of the mainstream thermal infrared remote sensors can be calibrated and validated using Xilinhaote meadow surface.

Allelopathy of Chamaecrista spp on Paspalum notatum under aluminum and magnesium stresses

GAO Cheng-fang, WENG Bo-qi, WANG Yi-xiang, XU Guo-zhong

2009, 18(5):  40-45. 

Asbtract ( 743 )   PDF (1024KB) ( 552 )  

References | Related Articles | Metrics

The allelopathy of Chamaecrista spp on P. notatum under different aluminum and magnesium stresses was studied. Aluminum and magnesium stresses affected the allelopathy. At three concentrations, C. rotundifolia inhibited the growth of P. notatum. The most significant inhibition effect was when the concentration of aluminum was 0.7 g/L. C. nictitans inhibited the growth of P. notatum when the concentration of aluminum was 1.1 g/L and the concentration of magnesium was 0.060 and 0.123 g/L. In general, allelopathy was stronger in the roots than in seedlings.

Research on allelopathic effects of Conyza canadensis-an invasive species

GAO Xing-xiang, LI Mei, GAO Zong-jun, SUN Ting-lin, SUN Zuo-wen

2009, 18(5):  46-51. 

Asbtract ( 896 )   PDF (742KB) ( 593 )  

References | Related Articles | Metrics

Allelopathic effects of aqueous extracts from C. canadensis were tested with apetri dish cultivation methods. They strongly inhibited the germination and seedling growth of Cucumis sativus, Brassica campestris, Digitaria sanguinalis, Echinochloa crusgalli and Amaranthus retroflexus. B. campestris was more sensitive than the other species. At 0.025 0 g/mL the germination of B. campestris, A. retroflexus, D. sanguinalis, C. sativus and E. crusgalli were 0, 6.67%, 9.09%, 40.00%, and 50.00%, respectively. The germination speed reflected the germination percentage, but was more sensitive. The roots were inhibited more strongly than seedling height at the same concentrations.

Osmotic adjustment substance responses of four Elytrigia repens re-watered after drought stress

SUN Zong-jiu, LI Pei-ying, Abulaiti, CHEN Le-ning

2009, 18(5):  52-57. 

Asbtract ( 650 )   PDF (820KB) ( 508 )  

References | Related Articles | Metrics

The physiological responses to water shortage of four E. repens re-watered after drought stress was studied in a pot experiment. Soil water content showed a decreasing trend with a significant (P<0.05) difference in the soil water content after 0, 5, 10, and 15 days of re-watering following drought stress. After re-watering, the leaf water saturation deficit of E. repens increased, while the contents of soluble protein, proline, and free amino acid initially decreased but then increased. The soluble carbohydrate content decreased. There was a negative correlation between free amino acids, proline and soluble carbohydrate, and it was significant (P<0.01) between soluble carbohydrate and free amino acid. By comprehensive analysis, the sequence of drought resistance of E. repens materials was E22>E5>E16>E1. When the soil water content reached 39.47%, E. repens began to suffer drought stress and irrigation was needed.

Studies on reproductive allocation, floral size and its trade-off with floral number of annual Gentiana

CHEN Xue-lin, LIANG Yan, QI Wei, SU Mei, DU Guo-zhen

2009, 18(5):  58-66. 

Asbtract ( 745 )   PDF (1198KB) ( 704 )  

References | Related Articles | Metrics

The reproductive allocation and the trade-off between flower size and flower number of five annual plants of Gentiana in Eastern Qinghai-Tibet Plateau Alpine Meadow were studied. 1) The mass of reproductive structure increased significantly with increasing individual size; 2)There was not certain correlation between reproductive allocation and size of individuals, which suggest species-specific adaptive strategies; 3)Both floral display size and total flower production are increasing with plant size, and the flower number is increasing more remarkably than flower size; 4)The trade-off between total flower production and flower size is exist after controlling for plant size statistically. This result confirms the theory predicts.

Applying grey correlative degree analysis to comprehensively evaluate growth performance of 17 types of alfalfa with different fall-dormancy grades

YANG Zhao, ZHANG Xin-quan, LI Xiang-lin, WAN Li-qiang, HE Feng

2009, 18(5):  67-72. 

Asbtract ( 752 )   PDF (463KB) ( 377 )  

References | Related Articles | Metrics

In this study, adaptation performance characters such as biomass per plant, plant height, leaf length, leaf, width, regrowth rate, length of taproot, and crude protein content of 17 alfalfa varieties grown in the southwest area of Hunan province were measures and analyzed by the grey correlative system, to establish varieties assessment models. The alfalfa varieties, including Millennium, Powerplant, and CW680, performed well in the study area, whereas the other varieties had relatively low adaptive productivities. The order of weight index in the grey correlation analysis was: CP>leaf length>leaf width>thick of stem>height length>regrowth rate>length of taproot>fresh/dry>rootstalk diameter>biomass per plant>number lateral root leaf/stem>root weight. These Results offer scientific evidence for introducing and extending alfalfa production in sub-tropical regions of south China.

Effects of additives on silage quality and in vitro digestibility of Lespedeza hedysaroides silage

YU Zhu,WEI Xin, YU Yan-dong, HAN Jian-guo, SUN Qi-zhong

2009, 18(5):  73-79. 

Asbtract ( 589 )   PDF (379KB) ( 438 )  

References | Related Articles | Metrics

Lespedeza hedysaroides silage was made from L. hedysaroides alone or by adding LaLsIL dry (0.000 5%, 0.001 0%, 0.002 0%, 0.007 0%) and Micromanger H/M (0.001 135%, 0.003 405%, 0.004 450%). L. hedysaroides was ensiled in plastic bags under vacuum. After 90 days, samples were analysised for silage quality and in vitro digestibility of L. hedysaroides. The treatments with LaLsIL dry and Micromanger H/M had higher lactic acid contents than the CK (P<0.05) while the content of butyric acid and ammonium nitrogen were lower (P<0.05). The Flieg evaluation method of silage showed that the fermentation quality was worst in directly ensiled L. hedysaroides, and that both treated silages had better fermentation quality than the CK. The treatments of LaLsIL dry and Micromanger H/M improved the fermentation quality and in vitro DM, CP and NDF digestibility of L. hedysaroides silage.

Forage quality of maize (Zea mays) stover among different varieties

TAI Shu-jing, ZHANG Ren-he, SHI Jun-tong, XUE Ji-quan

2009, 18(5):  80-85. 

Asbtract ( 568 )   PDF (692KB) ( 724 )  

References | Related Articles | Metrics

Maize stover is the important resource as forage. With technique of near infrared reflectance spectroscopy, forage quality traits such as in vitro dry matter digestibility(IVDMD), acid detergent fiber(ADF), neutral detergent fiber(NDF)and water soluble carbohydrate(WSC) of maize stover about 44 varieties were evaluated. The Results showed that there were significant differences in IVDMD, ADF, NDF and WSC among varieties. The four forage quality traits were almost accorded with normal distribution respectively. IVDMD ranged from 38.60% to 51.74%, ADF ranged from 27.01% to 35.67%, NDF ranged from 51.55% to 65.81% and WSC ranged from 4.69% to 12.21%. The coefficient of variation(CV)of WSC was the highest which was 23.59%. IVDMD was significantly and negatively associated with ADF and NDF, and positively associated with WSC. There was a significantly positive correlation between ADF and NDF. WSC was significantly and negatively associated with ADF and NDF. There were five elite varieties with high IVDMD and WSC and low ADF and NDF.

A study on mixed silage of alfalfa and maize straw

SUN Xiao-long, ZHOU He, LI Ping, YU Zhu

2009, 18(5):  86-92. 

Asbtract ( 732 )   PDF (388KB) ( 606 )  

References | Related Articles | Metrics

Maize straw and second cut alfalfa was completely mixed and treated with lactobacillus(LAB), cell wall degrading enzymes (ENZ), previous fermentation juice (PFJ), LAB and ENZ, PFJ and ENZ. Mixed ensiling maize straw and alfalfa improved the preservation of silage; all the different mixed ratio silages had a high fermentation quality; all the additives improved the fermentation quality further; there was little butyric acid in any of the silages. All the pH values were less than, or close to, 4.2. The ENZ+LAB treatment was the best, and its V-Score was also the best of the treatments. The ENZ treatment significantly (P＜0.05) reduced NDF content by 3.77% and CP content (P＜0.05) by 6.0% in the 7∶3 mixed ration.

Effects of ultradrying storage on vigor and antioxidase activity of Cichoriun intybus seeds

JIANG Yi-bao, ZHENG Qiu-hong, WANG Cheng-zhang, GUO Yu-xia, LI De-feng

2009, 18(5):  93-97. 

Asbtract ( 756 )   PDF (689KB) ( 707 )  

References | Related Articles | Metrics

In this experiment the effects of ultra drying treatment on vigour and antioxidase activity of C. intybus seeds was studied. Seeds of C. intybus were ultra dried with silica gel to reduce the moisture content to concentrations of 8.45%, 5.17%, 3.64%, 2.33%, and 1.69%. Seeds were then sealed in aluminium foil bags and stored in a calorstat at 50°C for 10 d. The seed vigor and antioxidase activities were assessed after they were re-moistened. There were no significant changes of seed physiological parameters under ultradrying or non-ultradrying treatments before temperature treatment. Seed germination rate and vigor index of C. intybus seeds were higher than those of the control under conditions of ultra drying after temperature treatment while the electric conductivity and MDA content were lower than those of the control. The activity of dehydrogenase, peroxidase and hydrogen peroxidase were higher than those of the control. For ultra drying of seeds, 2.33% moisture content was better than other moisture contents for storage effectiveness. The Results demonstrated that with an appropriate ultradrying treatment, C. intybus seeds can maintain robust vitality with enhanced storage effectiveness and thus provide a basis for suitable storage of C. intybus Seeds.

Study on biomass and root system distribution characteristics of sport turf in different substrate compositions

HUANG Xiao-lu, LIU Jun, YANG Zhi-min

2009, 18(5):  98-106. 

Asbtract ( 787 )   PDF (816KB) ( 534 )  

References | Related Articles | Metrics

This research used nine turf-bed compositions to analyze the biomass and root distribution characteristics of Bermuda T-419, a commonly used sports turf in the tropics and subtropics. Above and belowground biomasses of treatments showed similar changes, middle sediment treatments Ⅲ and Ⅶ were highest in above and belowground biomass. Root biomasses of the different treatments were significantly reduced with soil depth, and distribution of roots was concentrated in the 0-10 cm layer. Variance analysis indicated significant differences in the 0-10 cm belowground biomass between treatments and that treatments Ⅲ, Ⅵ and Ⅶ were significantly higher than Ⅰand the CK. There were no significant differences in biomass in the10-20 cm and below 20 cm soil layers. The correlation coefficient between belowground biomass and total root length was 0.541 (P<0.05), between belowground biomass and root surface-area with root volume it was 0.651 and 0.615 respectively (P<0.01), and between root number and total root length, with average diameters it was 0.500 and 0.695 respectively (P<0.01).

Preliminary evaluation on salinity tolerance of excellent selections and cultivars of warm season turfgrass

CHEN Jing-bo, YAN Jun, JIANG Yan-qin, GUO Hai-lin, ZHANG Ting-ting, CHEN Xuan, LIU Jian-xiu

2009, 18(5):  107-114. 

Asbtract ( 658 )   PDF (425KB) ( 695 )  

References | Related Articles | Metrics

The salinity tolerance of fifty excellent selections and cultivars of warm season turfgrass belonging to five genera and twelve species was determined by leaf firing percentage in hydroponic culture. There were wide variations of salinity tolerance among the fifty selections and cultivars, and the total coefficient of variation (CV) reached 60%. CVs of the genera Zoysia and Cynodon reached 52% and 29%, respectively. Between species, the maximum variation occurred in species of Z. japonica and Z. sinica, where CVs reached 56% and 52%, respectively. Generally, accessions of Z. tenuifolia and Z. matrella had the best salinity tolerance. Paspalum vaginatum ‘Adalayd’, Stenotaphrum secundatum ‘S004’, and some accessions of Z. japonica and Z. sinica were more saline tolerant. Accessions of Cynodon and other accessions of Zoysia were intermediate or low in tolerance. Two accessions of Eremochloa ophiuroides were salt-sensitive. In the genus Zoysia there was better salinity tolerance than in the control cultivars in seven and twelve accessions of ‘Manilagrass’ and ‘Lanyin No. 3’, respectively. Most accessions of Cynodon were more salinity tolerant than the control cultivars (‘Tifgreen’ and ‘Tifdwarf’ ) with the exception of ‘C158’, ‘Nanjing’ bermudagrass and ‘C610’. In total, the most salinity tolerant three selections or cultivars of the fifty accessions were Z. tenuifolia ‘Z160’, Z. matrella ‘Diamond’ and ‘Z075’.

Effects of alfalfa saponins on the nutrient digestibility, production performance and blood biochemical index of weaned piglets

WANG Yan-hua,WANG Cheng-zhang, GAO Yong-ge, YAN Xue-bing, SHI Ying-hua, HE-Yun

2009, 18(5):  115-122. 

Asbtract ( 804 )   PDF (427KB) ( 609 )  

References | Related Articles | Metrics

The Objective of this study was to evaluate the effects of alfalfa saponins on growth performance and blood biochemical index of weaned piglets. The Piglets were weaned at 9.2 kg and divided into 4 treatments with three replicates each treatment, and four Piglets per replicate according to birth date, litter, and gender, using complete random single factorial design. The levels of alfalfa saponins were 0%, 0.25%, 0.5%, and 1.0%, respectively. The Results showed that: 1) The daily gain of piglets fed with 0.25% and 0.50% alfalfa saponins were significantly higher than that of control group, and their relative growth rate were increased, and the feed weight ratio of the trial groups were lower compared control group. 2) Alfalfa saponins had positive influence on the digestibility coefficient of crude fat, crude ash and neutral detergent fiber for feed; however, the digestibility coefficient of crude protein in feed was reduced. 3) The number of red blood cell and white blood cell of blood was improved when the piglets was fed with alfalfa saponins, for example, those of 0.50% group were very significantly higher than that of control group(P<0.01). 4) The Urea nitrogen content of the trial groups was significantly lower than that of control group. With the alfalfa saponins level increased, the aspartate aminotransferase activity was increased, but the serum glucose was opposite (P>0.05), alkaline phosphatase content of the trial groups were very significantly higher than that of control group(P<0.01). The result of the study suggested that the suitable alfalfa saponins can improve the production of weaned piglets, and the appropriate amounts of alfalfa saponins in weaned piglets diet was between 0.25%-0.50%.

Comparisons of soil animal community characteristics of subalpine meadow between winter and spring in Miyaluo

WU Peng-fei, LIU Xing-liang, LIU Shi-rong

2009, 18(5):  123-129. 

Asbtract ( 737 )   PDF (701KB) ( 552 )  

References | Related Articles | Metrics

Soil animals are an important component part of the terrestrial ecosystem, and they could be used as indicator species to monitor and evaluate soil quality and health with effects on material cycles. The investigations were conducted on soil animal communities of the subalpine meadow in Miyaluo area, located in northwestern Sichuan, in November of 2007 and April of 2008. A total of 320 large-sized soil animals, belonging to 2 phyla, 4 classes and 15 groups or orders, and 6,081 middle-small-sized soil animals, belonging to 4 phyla, 7 classes and 16 groups or orders, were collected. The dominant groups of the large-sized soil animal community were Diptera larvae, Coleoptera larvae and Coleoptera adult while that of the middle-small-sized soil animal community was Nematoda. The community structures of soil animals changed significantly between the winter and spring, but the groups and individual numbers between the two seasons did not change significantly (P>0.05). The Margalef index of the middle-small-sized soil animal community significantly declined from winter to spring (P<0.05) but the other diversity indexes did not change significantly. The number of groups or individual soil animals decreased significantly (P<0.05) with soil depth but the differences between the seasons of spring and winter were not significant. The species compositions of soil animal communities in subalpine meadow ecosystems in northwestern Sichuan have higher individual densities that are different from those of the grassland ecosystems in the north of China.

Species and fauna of Argidae (Hymenoptera) in Nanling Mountains, China

YOU Qun

2009, 18(5):  130-135. 

Asbtract ( 487 )   PDF (546KB) ( 453 )  

References | Related Articles | Metrics

There were 28 species of Argidae in Nanling Mountains, belonging to Tenthredinoidea in Hymenoptera. Among them, 3 species were endemic to Nanling Mountains. The fauna analysis showed that Oriental species were predominant in Argidae in Nanling Mountains. There were 22 Oriental species, which accounted for 78.57% of all species in Nanling Mountains. The other 6 species were Palaearctic and Oriental species. There were 9 distribution patterns of Argidae in Nanling Mountains in Chinese geographical distribution altogether. The Central China and South China Argidae species were the most, and then Central China species, the ratio of them to the total Argidae species in Nanling Mountains reached 60.72%. All Jaccard similarity coefficients in different nature reserves, different altitudes, and different vegetation types in Nanling Mountains were below 0.5, which were ultimate dissimilarity or middle dissimilarity.

Analysis of community characteristics of nematodes in turf soil of Yongfeng virescence region in Beijing

LIU Qi-zhi, LIANG Lin-lin, YANG Duan, BIAN Yong, ZHOU Hai-ying, XIE De-yan

2009, 18(5):  136-141. 

Asbtract ( 524 )   PDF (620KB) ( 653 )  

Related Articles | Metrics

A comparison of trophic groups and quantity of nematodes in wilted and healthy turf soil in Yongfeng virescence region of Beijing was done to study the relationship between nematodes and turf wilt. Nematodes in the 0-20 cm depth of soil, whether in wilted or in healthy turf, belonged to 12 genera in 9 families of 5 orders. Harmful nematodes (phytophage nematodes, PPNs) were classified into 5 genera in 4 families of 2 orders and beneficial nematodes (non PPNs) were classified into 7 genera in 5 families of 3 orders. PPNs were absolutely dominant in wilted turf soil and accounted for 87.89% of the total number of nematodes. This was seven times more than other trophic groups (12.05%). Among PPNs, the quantity of nematodes in the genera Helicotylenchus, Pratylenchus and Trichodrus in wilted turf soil were double that in healthy turf soil. The Wasilewska index (WI) indicated that the soil health of healthy turf in Yongfeng virescence region of Beijing, has a potential crisis, while the problem is even worse in the rhizosphere of wilted turf.

Point pattern analysis of Seriphidium transiliense populations under two degradation gradients in the Northern Tianshan Mountains

LU Wei-hua, ZHU Jin-zhong, WANG Dong-jiang, JIN Gui-li, YU Bo

2009, 18(5):  142-149. 

Asbtract ( 504 )   PDF (1153KB) ( 487 )  

References | Related Articles | Metrics

Ripley’s K function was used to analyse spatial patterns and association of S. transiliense populations in severe and extreme degradation regions. In a 20 m series spatial scale, the S. transiliense population was usually characterized by nonrandom (clumped) distribution in a seriously degraded region. The clumped intensity was different and showed a “clumped wave” phenomenon on a different scale. The S. transiliense population was usually characterized a by clumped distribution on a small-scale in an excessively degraded region, but when it reached the threshold of the clumped distribution, then it shifted to a random distribution. Analysis of the spatial association of two sizes of S. transiliense showed that the size 2 individuals had a clumped distribution in seriously degradation regions, but the clumped intensity of the larger individuals was weaker. The size 1 had a small-scale clumped distribution in the badly degradation region, with a shift to random or regular distribution with increase of the spatial scale. Size 2 had a random distribution. According to spatial association analysis, the two sizes of S. transiliense populations had a positive small-scale association in two degradation gradients, but the association waned with an increase of scale, and the scope of the scale was different when the two sizes of populations represent a positive association.

Response to cutting treatment of interspecific relationships of leguminous forages in semiarid regions

ZUO Sheng-peng, WANG Hui-mei, MA Yong-qing, LI Feng-ming, SHAN Lun

2009, 18(5):  150-159. 

Asbtract ( 584 )   PDF (704KB) ( 599 )  

Related Articles | Metrics

The growth response of simple and artifical communities of Astragalus adsurgens and Medicago sativa to cutting treatments based on a biological replacement method was investigated. A relative study of interspecific relationships and compensative effects of both leguminous forages was done at three sowing densities for monoculture and mixtures and compared with cutting grass. The possible mechanisms for communities maintaining stable and successive status is discussed. Compared with the control, the cutting treatment led to a competitively spatial increase of about 20 cm in soil water utilization by A. adsurgens and M. sativa. This inducible effect increased soil moisture absorption by about 15%. In particular, the cutting treatment significantly enhanced water use of mixtures by 15.6% in low density sowings and by 33% for monocultures of M. sativa in high density sowings. In addition, cutting treatment induced an aerial biomass increase of 29% in A. adsurgens monoculture in the middle and high density sowings. However, plant height, branch numbers per plant, and aboveground biomass declined under the cutting treatment compared with the control. A. adsurgens and M. sativa showed weak resources-sharing with a decline of nearly 21% if artificially regulated by cutting and the relative competition of M. sativa to A. adsurgens was increased by 17%. Whether in monoculture or in a mixture, cutting would increase the compensatory effect of both forages. It was also found that cutting caused drastic density-limiting effects. The low productivity from additional cutting resulted from the synergistic effect of pressures such as arid circumstances, interspecific competition and allelopathic potential, which can be alleviated by coexistence and compensation. In the present study, the growth response and interspecific relationship resulting from cutting can indicate some potent mechanisms for maintaining the biodiversity of communities and the sustainable development of the forage industry.

Effects of the grazing systems on diurnal variation of photosynthetic characteristic of major plant species of desert steppe

YAN Rui-rui, WEI Zhi-jun, YUN Xiang-jun, CHU Wen-bin, Wuren-qiqige, XIN Xiao-ping

2009, 18(5):  160-167. 

Asbtract ( 654 )   PDF (1538KB) ( 418 )  

Related Articles | Metrics

A comparison of rotational grazing and continuous grazing was conducted on Stipa breviflora desert steppe in the Sunit Right Banner of Inner Mongolia. The study on response of diurnal variation of photosynthetic characteristic of major plant species in different grazing system showed: 1) Double-peaks on the curves of diurnal changes of photosynthetic rates, transpiration rates and stomatal conductance of S. breviflora, Cleistogenes songorica and Allium polyrhizum, and there was a distinct phenomenon of “noon break”. There was a double-valley on the curves of diurnal changes of internal CO₂ concentration. 2) The different grazing regimes had no effect on the net photosynthetic rate or transpiration of the main plant species, but doubled the peak time in other the same conditions. 3) Rotational grazing and banning grazing increased stomatal conductance and internal CO₂ concentration of C. songorica.

Tissue culture and plantlet regeneration from vegetative organs of two clones of tall fescue (Festuca arundinacea)

ZHAO Zhi-yan, PAN Jun-song, HE Ya-li, WANG Chen, YAN Jun-hui

2009, 18(5):  168-175. 

Asbtract ( 639 )   PDF (950KB) ( 502 )  

Related Articles | Metrics

In an effort to optimize the tissue culture response of a tall fescue (Festuca arundinacea) regeneration system, the effects of 2,4-D on tissue culture responses were investigated using immature inflorescences, leaf tips, young stems, and young nodes as explants. Two clones (SACD and 98-19), which are self-bred dwarf clones of tall fescue were used. Immature inflorescences were the best vegetative organ for callus induction, with the highest callus induction rate of 94%. For tips of leaves, stems and nodes, the callus induction rate was 0%; the optimal concentration of 2,4-D was from 7 to 9 mg/L in MS with a callus induction rate of 83% to 94%. Significant differences were also observed between the tested clones but the interaction between 2,4-D concentrations and the clones was not significant. Subculture medium of 2,4-D 4 mg/L in MS resulted in the highest embryogenic callus induction rate (98%), highest green spot induction rate (78%) during subculture, and high green plant regeneration rate (57%) in regeneration medium of “MS+2,4-D 2 mg/L+6-BA 1 mg/L”. The rooting medium used (“1/2 MS+NAA 0.5 mg/L”), gave a rooting rate of 100%.

Cloning and sequence analysis of aNa⁺/H⁺ antiporter gene in the halophyte Limonium gmelinii

ZHOU Ling-ling, MIAO Jian-kun, ZHU Jian-bo, CAO Lian-pu

2009, 18(5):  176-183. 

Asbtract ( 520 )   PDF (1938KB) ( 475 )  

Related Articles | Metrics

A vacuolar-typed Na⁺/H⁺ antiporter gene was isolated from the halophyte L. gmelinii by RT-PCR and RACE. The LgNHX1 cDNA was 2 397 bp including a 5′untranslated region of 512 bp and a 3′-nontranslated region of 229 bp with poly A, and an open reading frame of 1 656 bp, encoding a predicted polypeptide of 550 amino acids with a predicted molecular mass of 61 kD. It was shown by multiple sequence alignment analysis that the LgNHX1 were 82.62%, 82.01%, 80.64% and 75.86% identitical in amino acids to the vacuolar-typed Na⁺/H⁺ antiporter genes from Atriplex gmelini, Tetragonia tetragonioides, Salicornia europaea and Arabidopsis thaliana, respectively. TMpred prediction showed 11-12 transmembrane domains of LgNHX1. Phylogenetic analysis indicates that LgNHX1 is more related to the vacuolar-typed Na⁺/H⁺ antiporter, compared with the plasma membrane-type Na⁺/H⁺ antiporter, to which it is less related.

Genetic diversity markers detected by inter-simple sequence repeats (ISSRs) in Crotalaria latifolia in Yunnan

LIU Zhong-hui, LIU Guo-dao, HUANG Bi-zhi, LUO Fu-cheng

2009, 18(5):  184-191. 

Asbtract ( 492 )   PDF (648KB) ( 517 )  

Related Articles | Metrics

Forty-one Crotalaria latifolia wild resources in Yunnan were analyzed using inter-simple sequence repeats (ISSR). Sixteen of 100 primers were selected, and 164 DNA fragments were amplified from 41 samples to give 159 fragments (99.3%) that were polymorphic, an average of 10.3 DNA bands per primer. The genetic similarity among all accessions ranged from 0.481 7 to 1.000 0, indicating a comparatively rich genetic diversity among the tested accessions. A better PCR reaction system was obtained using an orthogonal design: DNA 40 ng, primer 0.2 μmol/L, dNTP 200 μmol/L, 1×Buffer (Mg²⁺ plus), Taq polymerase 0.5 U (TaKaRa). The best annealing temperature for ISSR primers was 50 or 53℃. UPGMA cluster based on genetic similarity divided the accessions into five groups, with close intraspecific germplasm. Crotalaria szemoensis was identified by ISSR and its genetic similarity was close to Crotalaria but more work is needed to identify this species.

Genetic diversity of wild Elymus nutans germplasm detected by SRAP markers

CHEN Zhi-hua, MIAO Jia-min, ZHONG Jin-cheng, MA Xiao, CHEN Shi-yong, ZHANG Xin-quan

2009, 18(5):  192-200. 

Asbtract ( 649 )   PDF (923KB) ( 545 )  

Related Articles | Metrics

Sequence-related amplified polymorphism (SRAP) molecular markers were used to detect the genetic diversity of 68 accessions of Elymus nutans collected from Gansu, Sichuan, Tibet, Qinghai, and Xinjiang areas of China. Twenty primer pairs produced 495 bands (average of 24.75 bands per primer pair), including 425 polymorphic bands (21.25 bands per primer pair). The average percentage of polymorphic bands was 85.39%. The Nei’s genetic similarity coefficient of the tested accessions ranged from 0.374 to 0.997, and the average Nei’s coefficient was 0.745. These Results suggest that there was a rich genetic diversity among the resources of Elymus nutans tested. The 68 accessions can be clustered into five dendrogram groups at the GS=0.77 level. The principal coordinates (PCA) reflected almost the same relationships among the studied materials as found in cluster analysis. Moreover, the accessions from the same origin frequently clustered into one group. The findings indicated a correlation among the wild resources and their geographical and ecological environments.

Genetic diversity and relationships of zoysiagrass as revealed by SRAP markers

GUO Hai-lin, ZHENG Yi-qi, CHEN Xuan, XUE Dan-dan, LIU Jian-xiu

2009, 18(5):  201-209. 

Asbtract ( 607 )   PDF (1696KB) ( 561 )  

Related Articles | Metrics

The genetic diversity and relationships of 98 germplasms of five species and one variety of Zoysia were analyzed using SRAP markers. A total of 362 bands were detected with 54 pairs of SRAP primers and 337 of the bands were polymorphic (PPB=93.09%). The Nei’s gene diversity index (H) was 0.240 9 and the Shannon diversity index (I) was 0.374 6, indicating a high level of genetic diversity of zoysiagrass. The genetic similarity (GS) among 96 Zoysia germplasms ranged from 0.593 9 to 0.983 4 with an average of 0.758. Eight showed that a large genetic polymorphism existed among the germplasms of Zoysia grass. The GS between Z. japonica and Z. sinica, and between Z. matrella and Z. tenuifolia were relatively high compared with the GS of other species. The variance ranges of GS within species of Z. japonica, Z. sinica and Z. matrella were 0.599 4－0.983 4, 0.624 3－0.980 7 and 0.663 0－0.947 5, respectively. Based on the presence of bands, 96 zoysia germplasm were classified into seven major groups by UPGMA cluster analysis, in which group I and group II included three species of Z. Japonica, Z. sinica and a few accessions of Z. matrella. Group III included four accessions introduced from America. Group IV mainly comsisted of Z. matrella and Z. tenuifolia. Z. machrostachya (Z010), Z .sinica var nipponica (Z122) and Z. sinica (Z115) formed a group by themselves. The Results of UPGMA cluster showed that some accessions of Z. japonica, Z. sinica and Z. matrella clustered into one group: no one species clustered into one group, Moreover, a very few groups contained only one accession, suggesting that it had a special genetic base. In this paper, the diversity and relationships among 96 germplasms have been investigated and a preliminary discussion made on the ownership of part accessions. This research should provide a scientific basis at the molecular level for further study and the application of Zoysia grass germplasms.

Integrated crop-livestock production system

HOU Fu-jiang, NAN Zhi-biao, REN Ji-zhou

2009, 18(5):  211-234. 

Asbtract ( 1092 )   PDF (1479KB) ( 1683 )  

Related Articles | Metrics

Both crop and livestock play key roles in agricultural system. In the integrated crop-livestock production system, there is an intact net of matter flow and energy flow between crop sub-system and livestock sub-system and residues of one sub-system often are used as raw material of another one. The interaction between crop and livestock has promoted evolution of agricultural system and there have been six stages: Originally hunting and foraging system (OHF), originally integrated crop-livestock production system (OICL), extensively specialized production system (ES) including extensively specialized crop production system (ESC) and extensively specialized livestock production system (ESLP), extensively integrated crop-livestock production system (EICL), intensively specialized production system (IS) including intensively specialized crop production system (ISC) and intensively specialized livestock production system (ISL), intensively integrated crop-livestock production system (IICL). And there have taken place two specializations and three integrations of crop production and livestock production during evolution of agricultural system and productivity has risen in a spiral. Integrated crop-livestock production system comprises six dominant types: classical system (C-ICL), system based on rangeland (ICL-R), system based on crop/forage rotation (ICL-CF), system based on sown pasture (ICL-SP), system based silvo-pasture (or woodland) (ICL-W, agro-silvopastoral system) and system based on pond (ICL-P). Furthermore, one type of system could succeed to the other one along the given environmental gradient. Intensive agricultural system is mainly prevalent in developed countries, whilst extensive one is dominant in developing countries, and intensive system is significantly different from extensive system in light of components, interaction of crop and livestock, input of outside, productivity and management goals. Crop-livestock interaction in integrated agricultural system has significantly positive effects on soil quality, crop production, microorganism activity, livestock production, nutrition circle, energy efficiency and economic profitability. In terms of property, succession, structure and function of integrated crop-livestock production system, there exit some similarities and distinctions between domestic and international research. However, the current research is in face of some common difficulties, which mainly include incompleteness of research object, singleness of research scale, unreliable methods, ignoration of livestock subsystem and gap between energy analysis and matter analysis.

Progress in vitamin E synthesis-related enzyme gene cloning and stress physiology in plants

ZHANG Yi-gong, ZHANG Li-jing, FU Hua

2009, 18(5):  235-243. 

Asbtract ( 560 )   PDF (567KB) ( 763 )  

References | Related Articles | Metrics

Vitamin E is an important class of lipid-soluble compounds with antioxidant activities. It can be synthesized in the photosynthetic organs of higher plants and cyanobacteria. The eight natural products of vitamin E (designated as α,β,γ,δ-tocopherol and α,β,γ,δ-ocotrienol) play an important role in human and animal life. In this article, the metabolic process of vitamin E in vivo, the current progress in synthesis-related enzyme gene cloning and manifestations of vitamin E transgenic plant in abiotic stress are summarized. At present, all the enzyme genes for vitamin E synthesis have been cloned from the model plant Arabidopsis thaliana and from Cyanobacteria. Vitamin E genes in over 26 plants have also been cloned and the functions of antioxidant activities have been preliminarily clarified. In future work, the function and the relationships of vitamin E should be further clarified, especially the tocotrienols. The important values of tocopherols should be extended by the use of genetic engineering.

Progress in research on root invading fungi of Medicago sativa

GUO Yu-xia, NAN Zhi-biao, WANG Cheng-zhang, LI Chun-jie, SHEN Yu-ying, YAN Xue-bing

2009, 18(5):  243-249. 

Asbtract ( 860 )  

References | Related Articles | Metrics

Medicago sativa is one of the important legumes in the world. Root rot disease is one of the limiting factors for its production and persistence. Based on the literature published during the past 25 years on pathogens and their pathogenicity in the world, lots of factors affecting disease development of M. sativa were reviewed, including disease development such as plant growing period, soil fertilizer and crop rotation in the field management. Finally, some suggestions are presented for future research.

Genetic differences of different reed ecotypes adapted to individual habitats

LIU Bin-bin, XING Jia-qiang, GONG Xiao-jie, PU Tong-liang

2009, 18(5):  250-255. 

Asbtract ( 704 )   PDF (546KB) ( 575 )  

References | Related Articles | Metrics

The genetic differences among different reed ecotypes was analysed on four ecotypes of reed (Phragmites communis) in Linze County, Gansu Province, using RAPDs and allozyme genetic diversity analysis. Ten base random primers were used in the RAPD analysis and 16 primers were chosen on the basis of repeatedly forming significant polymorphism products. Of a total of 559 amplification bands 489 (87.5%) were polymorphic. Using 12 allozyme loci, allozyme genetic diversity analysis, showed there were nine gene sites with polymorphisms. The average percentage of polymorphic sites was 34.1%. The Results indicated that notable molecular genetic diversity and different ecotype reed allozyme expression divesity existed among the different ecotypes but genetic diversity between individuals of the same ecotype was slight. This is consistent with the distinct differences between the habitats and together with the morphological and physiological variations, it demonstrates that these differences are involved in different reed ecotype genetic differentiation.

Effect of grazing intensity on characteristics of alpine meadow communities in the eastern Qinghai-Tibetan Plateau

REN Qing-ji, WU Gao-lin, REN Gou-hua

2009, 18(5):  256-261. 

Asbtract ( 1200 )   PDF (727KB) ( 1572 )  

References | Related Articles | Metrics

A comparative study on community characteristics with different grazing intensitie was conducted in alpine meadows of the eastern Qinghai-Tibetan Plateau (Maqu county, Gansu province). With increased grazing intensity, vegetation height, total cover and above-ground biomass all showed a significant decrease. The importance of species of Cyperaceae and Gramineae families fell and their dominances were replaced by some forbs species (Ligularia virgaurea and Leontopodium leontopodioides). For plant functional groups, the biomass proportions of the germinal species group and the sedge species group were significantly reduced by increased grazing intensity, but the biomass proportions of leguminous species group, forbs species group and noxious species group were significantly increased. Richness index (R), Shannon-Wiener diversity index (H) and Evenness index (E) of alpine meadow communities reached a maximum under the middle grazing intensity in the moderately-grazed plot>heavily-grazed plot>non-grazed plot. Results suggest that with increased grazing, alpine meadow communities will undergo a succession from “dominated by tall germinal and sedge species” to “dominated by tall germinal and sedge species+middle forbs species”, then to “dominated by middle and lower forbs species”.

A new probe in to the method of calculating pasture ecological livestock capability on the grass-livestock optimize

A new probe in to the method of calculating pasture ecological livestock capability
on the grass-livestock optimize
LI Hong-quan, GAO Lan-yang, LIU Gang, LI Hua-de
(1.Grassland Science Research Institute of Sichuan Province, Chengdu 611731, China; 2.Plant
Engineering Institute of Sichuan Province, Zizhong 641200, China)

2009, 18(5):  262-265. 

Asbtract ( 788 )   PDF (348KB) ( 580 )  

References | Related Articles | Metrics

Based on the previous research, a new method of calculating pasture ecological livestock capability was proposed on the grass-livestock balance in order to meet the requirements of development. New method finds out a balance between increasing herder income and protecting ecological environment on grasslands, and ensures the sustainable development of grassland animal husbandry.

A study on cadmium content of alfalfa at different growth stages and an evaluation of forage feed security

LI Xin-bo, XIE Jian-zhi, LI Bo-wen, WANG Wei

2009, 18(5):  266-269. 

Asbtract ( 582 )   PDF (404KB) ( 506 )  

Related Articles | Metrics

Pot experiments were conducted to study the influence of cadmium pollution on the branching and flowering stages of alfalfa, and to evaluate the safety for production of alfalfa. The biomass of alfalfa was more easily affected by Cd at the branching than at the flowering stage with soil concentrations of 0.37-20.37 mg/kg Cd. At both branching and flowering stages, the Cd contents in the body of the alfalfa plants were significantly positively correlated with Cd in the soils and at the branching stage were more than 2.9-28.5 times higher than at the flowering stage. At the flowering stage, the Cd contents of above-ground parts of alfalfa were 0.213 mg/kg dry weight and did not exceed the forage health standards (Cd: 0.5 mg/kg GB 13078-2001) when Cd was 5.37 mg/kg in the soil. Compared with the flowering stage, at the branching stage, the Cd contents of above-ground alfalfa parts exceeded the forage health standard. The contents of Cd in soils should not exceed 0.55 mg/kg at the branching stage and 9.37mg/kg at the flowering stage according to the fitted equation. In the above situations, Cd contents of above-ground alfalfa parts did not exceed the forage health standard.

Research on grassland resources yield and balance between forage resources and livestock numbers in Haidong and Haibei prefecture of Qinghai

LI Wen-juan, MA Xuan-long, CHEN Quan-gong

2009, 18(5):  270-275. 

Asbtract ( 1258 )   PDF (718KB) ( 923 )  

References | Related Articles | Metrics

Observed grassland yields from areas located by GPS in Haidong and Haibei prefecture of Qinghai, were used to design natural grassland yield estimating models with vegetation index of MODIS. Estimating models for maximum theoretical livestock carrying capacity were built. Livestock carrying capacity of added forage was calculated from by-products of farming and forest. Combing the reality of seasonal pasture in Qinghai, the models for balance between carrying capacity of natural grassland or added forage and actual number of livestock were established and the current states of both prefectures were analyzed. The grassland resources yields of Haidong and Haibei prefecture were 195.30×10⁴ and 4 590.92×10⁴ t, respectively. Grass forage intakes were 98.41×10⁴ and 2 306.07×10⁴ t, and the practical usage rates of natural grasslands were 50.4% and 50.23%. The maximum livestock carrying capacity of natural grassland in both prefectures were 90.97×10⁴ and 856.18×10⁴ sheep units respectively. Livestock overloading in Haidong was serious, being as high as 97.9%, but in Haibei the overloading rate was -32.2%.