干旱对大豆生理及产量影响的研究

干旱对农业生产影响巨大,开展干旱胁迫对大豆生理及产量影响的研究,将为干旱地区大豆生产提供理论依据。利用塑料整理箱进行了干旱胁迫对大豆光合生理、叶片抗氧化物酶和渗透调节物以及生物量、产量影响的研究,土壤水分为干旱(45%~55%的田间土壤最大持水量)和湿润(80%~100%的田间土壤最大持水量,CK)2个水平,进行了2年的试验研究。结果表明,干旱胁迫使大豆净光合速率、气孔导度、蒸腾速率均明显下降,使水分利用率增加;干旱胁迫对大豆叶片过氧化酶(POD)和超氧化物歧化酶(SOD)含量无显著影响;干旱使大豆叶片丙二醛(MDA)含量、还原糖含量和可溶性总糖含量增加25.00%,47.09%和47.16%。干旱胁迫使大豆株高、节数、茎粗明显下降。干旱使大豆地上部分生物量明显下降,其中2013年下降39.4%,2014年下降69.6%。干旱使大豆籽粒产量明显下降,2013,2014年分别下降46.9%和81.6%。干旱胁迫下,大豆叶片气孔导度显著下降,使CO2供应受到严重影响,降低叶片净光合速率。干旱胁迫还会使大豆细胞膜结构造成一定的破坏,影响植物正常的光合作用,使大豆光合代谢产物下降。虽然大豆可以通过渗透调节物质来保持细胞的水分,但干旱仍然抑制了植株的正常生长,使大豆生物量和产量下降。

Effects of Drought on Physiology and Yield of Soybean

Tremendous impact of drought on agricultural production,research drought stress on physiological and yield,will provide the basis for soybean production in arid areas.In this paper,the use of plastic storage box drought stress test were studied photosynthetic physiology,leaf osmotic adjustment and antioxidant enzyme composi-tion and biomass yield on the soil water into arid(45% -55% of the maximum water holding capacity of soil field) two horizontal and humid (80% -1 00% field soil water holding capacity,CK).The results showed that drought stress soybean net photosynthetic rate,stomatal conductance and transpiration rate decreased significantly,water use efficiency increased;drought stress on leaf peroxidase(POD)and superoxide dismutase(SOD)no significant effect on the content;malondialdehyde(MDA)content increased by 25.00%to reach a significant level;the amount of re-ducing sugars and total soluble sugars increased by 47.09% and 47.1 6%,respectively.Drought stress on soybean plant height,node number,stem diameter,aboveground biomass,yield decreased significantly.Under drought stress, soybean stomatal conductance decreased significantly,severely affected the supply of CO2 ,reducing the net photo-synthetic rate,so that the decline in soybean photosynthetic metabolism.Plant material can be adjusted to maintain the moisture permeation through the cell.Although soybeans can maintain cell moisture through osmotic adjustment substances,drought still inhibits normal plant growth and decreases soybean biomass and yield.