乙烯利对夏玉米子粒干物质积累的影响及生理机制探究

以郑单958为试验材料,于玉米第9展叶期喷施200、400、800 mg/L乙烯利,喷施清水作对照,测定子粒发育过程中灌浆速率及可溶性糖、淀粉和激素含量,考种计产。结果表明,400 mg/L和800 mg/L乙烯利处理显著降低郑单958的单穗重和千粒重,同时降低灌浆后期生长素(IAA)、脱落酸(ABA)和赤霉素(GA3)的含量及平均灌浆速率和最大灌浆速率,降低子粒中淀粉含量;200 mg/L乙烯利处理单穗重及灌浆速率与对照差异不显著。结合产量、干物质积累和激素含量变化分析,喷施高浓度乙烯利导致子粒中激素含量变化是子粒灌浆速率下降、干物质积累速率减慢和千粒重下降。建议生产中用200 mg/L乙烯利为主要喷施浓度。

Effects of Ethephon on Dry Matter Accumulation in Summer Corn Seeds and Related Physiological Mechanism Inquiry

By taking hybrids Zhengdan958 of materials,water and Ethephon of 200 mg/L,400 mg/L,800 mg/L were sprayed in the ninth expansion leaf period,the grain-filling rate,the content of soluble sugar,starch and hormone were determined,and production was also measured at harvest time.The results showed that Ethephon of 400 mg/L and 800 mg/L significantly decreased the spikelets and thousand seed weight,the content of IAA,ABA,GA₃,average grain-filling rate,maximum grain-filling rate and the content of starch in the seed.While 200 mg/L Ethephon had not significantly influence on the spikelets and average grain-filling rate.Compared with the production,the accumulation of dry matter and the content of the hormone,spraying high concentration of Ethephon which resulted in the change of content of hormone is the important reason of the decrease of grain-filling rate,dry matter accumulation and thousand seed weight.So we advise 200 mg/L Ethephon as the main concentration in production.