不同生育时期干旱对大豆主要生理参数及产量的影响

研究了不同生育时期干旱对大豆光合速率、硝酸还原酶活性、磷酸蔗糖合成酶和蔗糖合成酶活性等生理指标的影响以及对产量和产量构成因子的影响.结果表明,不同生育时期进行干旱处理均使光合速率硝酸还原酶活性、蔗糖合成酶活性和磷酸蔗糖合成酶活性降低,光合速率以分枝期到鼓粒期干旱处理降低幅度较大,硝酸还原酶活性以开花期干旱处理降低幅度最大,其次是分枝期和鼓粒期;蔗糖合成酶活性和磷酸蔗糖合成酶活性以开花期干旱处理降低幅度最大,其次是鼓粒期和分枝期;不同生育时期干旱处理均导致大豆产量构成因子和产量下降.每株荚数和每荚粒数以结荚期干旱处理降低幅度最大,其次是鼓粒期干旱处理、开花期干旱处理;百粒重以鼓粒期干旱处理降低幅度最大,其次是结荚期和开花期干旱处理.单株产量以结荚期干旱处理降低幅度最大,其次是鼓粒期、开花期干旱处理.开花期、结荚期和鼓粒期干旱对产量影响最大,在大豆生产中要特别注意这几个生育时期的水分管理.

EFFECT OF DROUGHT AT DIFFERENT GROWTH STAGES ON MAIN PHYSIOLOGICAL PARAMETERS AND YIELD IN SOYBEAN

Effeet of drought at different growth stages on physiologieal parameters, sueh as Pn, NRA, SS and SPS aetivity, yield and yield eomponents were studied in this artiele. Results showed that Pn, NRA, SS and SPS aetivity were all deereased by drought treatments at different growth stages. Pn was reduced mostly by drought treatment at braneh to grain-filling. NRA was deereased mostly by drought treatment at floreseenee, next were braneh and grain-filling. SS and SPS activity were deereased mostly by drought at florescence,next were grain-filling and braneh. Yield and yield eomponents were redueed by drought treatments at different growth stages. Legumes per plant and number of seeds per pod were decreased mostly by drought treatments at pod-setting next,were grain-filling and floreseence. Weight of 100-grain was decreased mostly by drought treatments at grain-filling next pod-setting and floreseence. Yield of single plant was decreased mostly by drought treatments at pod-setting,next were grain-filling and florescence. Effect of drought treatments at florescence, pod-setting and grain-filling on yield was significant and we should pay attention to moisture-managing at this growth stages in producing of soybean.