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草业学报 ›› 2024, Vol. 33 ›› Issue (11): 135-148.DOI: 10.11686/cyxb2023477

• 研究论文 • 上一篇    

非生物逆境锻炼对玉米镉胁迫的生理响应

李霄霄(), 张盼, 卢园, 李婷, 赵娜, 吴佳文()   

  1. 延安大学生命科学学院,陕西 延安 716000
  • 收稿日期:2023-12-13 修回日期:2024-01-31 出版日期:2024-11-20 发布日期:2024-09-09
  • 通讯作者: 吴佳文
  • 作者简介:E-mail: wujiawende@126.com
    李霄霄(1998-),女,陕西榆林人,在读硕士。E-mail: 975127498@qq.com
  • 基金资助:
    陕西省重点研发计划——一般项目(2023-YBNY-239);延安市科学技术协会青年人才托举计划项目(2023-42-10);国家自然科学基金项目(42167005);延安大学博士科研启动项目(YDBK2019-17)

Abiotic stress priming affects the responses of maize (Zea mays) plants to cadmium stress

Xiao-xiao LI(), Pan ZHANG, Yuan LU, Ting LI, Na ZHAO, Jia-wen WU()   

  1. College of Life Sciences,Yan’an University,Yan’an 716000,China
  • Received:2023-12-13 Revised:2024-01-31 Online:2024-11-20 Published:2024-09-09
  • Contact: Jia-wen WU

摘要:

我国耕地镉污染问题非常严峻,阐明非生物逆境锻炼对玉米镉胁迫的生理响应,一方面可利用降低镉积累的非生物逆境锻炼保障玉米的品质,另一方面还可利用促进镉积累的非生物逆境锻炼提高玉米修复镉污染土壤的效率。本研究选取干旱、盐胁迫、缺铁和低浓度镉预处理分别作为交叉和同种非生物逆境短期锻炼玉米幼苗,然后施加或不施加镉胁迫处理,测定不同非生物逆境锻炼后玉米在镉胁迫下的生物量、根系形态、耐受系数、镉浓度及积累量、镉的亚细胞分布,以及抗氧化防御系统能力的变化。结果表明:缺铁、盐胁迫和干旱锻炼降低了玉米根、茎和叶干重,但这些非生物逆境锻炼显著提高了玉米对镉的耐受系数。干旱锻炼降低了玉米根、茎和叶镉浓度及积累量,而且干旱锻炼促使更多的镉分布在液泡。相比之下,低浓度镉锻炼增加了玉米根和叶镉浓度及叶片镉积累量,但没有改变亚细胞镉的分布比例。非生物逆境锻炼对镉胁迫下玉米叶片和根超氧化物歧化酶(SOD)、过氧化物酶(POD)和过氧化氢酶(CAT)活性无显著性的影响,表明非生物逆境锻炼没有刺激抗氧化酶响应玉米的镉胁迫。通过相关性分析发现玉米总根长与非生物逆境锻炼下镉积累密切相关,叶片细胞壁镉浓度与玉米镉积累呈正相关,根液泡镉浓度与玉米镉积累呈负相关。非生物逆境锻炼能显著提高玉米耐镉性,其中干旱锻炼可应用于降低玉米积累镉。

关键词: 镉积累, 锻炼, 非生物逆境, 玉米, 抗氧化

Abstract:

Cadmium (Cd) pollution in arable land in China is becoming an increasingly serious problem. The aim of this study was to elucidate how various abiotic stresses prime the responses of maize (Zea mays) to Cd stress. On the one hand, abiotic stress priming that reduces Cd accumulation can be used to safeguard the quality of maize for consumption; on the other hand, abiotic stress priming that increases Cd accumulation in maize can be used to enhance phytoremediation efficiency when maize plants are grown in Cd-polluted soil. Maize seedlings were subjected to priming treatments for a short time. Drought, salt, and iron deficiency were used as cross-stress priming treatments, and a low dose of Cd was used as the same stress priming treatment. After the various stress treatments, the maize seedlings were subjected to Cd stress, and then their biomass, root morphology, tolerance index, Cd concentration, Cd accumulation, subcellular Cd distribution, and antioxidant defense capacity were determined. The application of iron deficiency, salt stress, and drought as stress priming treatments resulted in a reduction in the dry weight of maize roots, stems, and leaves. However, priming with these abiotic stresses significantly enhanced the tolerance indices of maize under Cd stress. Specifically, drought stress priming led to a decrease in the Cd concentration and accumulation in the roots, stems, and leaves of maize plants. Additionally, it promoted the localization of Cd in vacuoles. By contrast, priming with a low dosage of Cd enhanced Cd concentrations in roots and leaves and Cd accumulation in leaves, but did not alter the subcellular distribution of Cd. Priming with abiotic stresses did not significantly change the activities of superoxide dismutase, peroxidase, and catalase in the leaves and roots of maize plants under Cd stress, suggesting that abiotic stress priming does not stimulate the activities of antioxidant enzymes during the response to Cd stress in maize. Correlation analyses showed that total root length was closely correlated with Cd accumulation in maize. The total root length was affected by abiotic stress priming. Moreover, the Cd concentration in the leaf cell walls was positively correlated with Cd accumulation in maize. In contrast, the Cd concentration in vacuoles of root cells was negatively correlated with Cd accumulation in maize. Our results show that abiotic stress priming can significantly promote the Cd tolerance of maize, and that drought priming can decrease Cd accumulation in maize.

Key words: Cd accumulation, priming, abiotic stress, maize, antioxidant