摘要
为探究乳酸菌胞外多糖浸种对酸、盐胁迫条件下水稻生长发育的影响,采用室内恒温培养试验,研究不同浓度乳酸菌胞外多糖对水稻种子萌发及相关生理代谢指标的影响。结果表明,采用不同浓度胞外多糖浸种可以显著提高逆境胁迫下水稻种子的发芽势、发芽率及发芽指数,促进水稻根系生长,随着胞外多糖浓度的升高,对水稻种子萌发的促进作用呈先升高后降低趋势;胞外多糖浓度为200 mg·L^(-1)时,缓解逆境胁迫伤害效果最为显著;pH值为3.0的酸胁迫下,与不添加胞外多糖相比,水稻种子的发芽势、发芽率及发芽指数分别提高了178.2%、38.7%和114.4%;7 mg·mL^(-1)NaCl胁迫下,发芽势、发芽率、发芽指数分别提高了152.9%、73.8%、103.0%,且差异均达显著水平(P<0.05);胞外多糖浸种可显著降低各胁迫下水稻幼芽丙二醛(MDA)含量,不同程度地提高过氧化氢酶(CAT)、过氧化物酶(POD)、超氧化物歧化酶(SOD)等抗氧化酶活性,同时胞外多糖对经过逆境胁迫的水稻种子播种后生长的幼苗也具有一定的促进作用,可缓解逆境胁迫对水稻造成的毒害。本研究为微生物源物增强作物抗逆性研究提供了理论依据。
In order to investigate effect of exopolysaccharides(EPS) of lactic acid bacteria on the germination of rice seeds and physiological indexes of rice under acid and salt stress, different concentrations of EPS of lactic acid bacteria was applied to rice seed in their germination stage. The results indicated that the EPS can significantly increase seed germination potential, germination rate and germination index, root growth were also increased significantly. As the the EPS concentration increased, the trend of rice seed germination increased firstly and then decreased under different stress. The content of 200 mg·L^-1 EPS significantly alleviated the damage caused by acid and salt stress. Specifically, germination potential, germination rate and germination index were increased by 178.2%, 38.7% and 114.4% under acid stress, respectively. Under salt(7 mg·L^-1NaCl) stress, compared with without EPS, germination potential, germination rate and germination index were also increased by 152.9%, 73.8% and 103.0%, respectively. Their difference reached at a significant level(P<0.05). Further analysis showed that the process of soaking in EPS would reduce malondiadehyde(MDA)content and enhance the activity of antioxidant enzymes in varying degree such as catalase(CAT) activity, peroxidase(POD) activity, superoxide dismutase(SOD) activity of rice shoots, which could effectively alleviate the toxic effects of stress resistance. At the same time, EPS could also promote the growth of rice seedlings under stress. This study provides theoretical and practice foundation for improving crops stress resistance by microbe-derived.
作者
张文平
杨臻
吴佩佳
李依扬
程新
李昆太
ZHANG Wenping;YANG Zhen;WU Peijia;LI Yiyang;CHENG Xin;LI Kuntai(College of Biological Science and Engineering,Jiangxi Agricultural University,Nanchang,Jiangxi 330045)
出处
《核农学报》
CAS
CSCD
北大核心
2019年第1期138-147,共10页
Journal of Nuclear Agricultural Sciences
基金
国家自然科学基金(31460469)
江西农业大学大学生创新创业训练计划项目(201710410070)
关键词
乳酸菌
胞外多糖
水稻
种子萌发
胁迫
lactic acid bacteria
exopolysaccharides
rice
seed germination
stress
