不同熟期夏玉米品种籽粒灌浆脱水特性和激素含量变化

本文旨在研究不同熟期夏玉米品种籽粒灌浆与脱水特性和内源激素含量与平衡的变化,以期为黄淮海夏玉米机械化收获籽粒和高产高效品种筛选提供理论依据。以早熟玉米品种登海518(DH518)、衡早8号(HZ8)和晚熟玉米品种郑单958(ZD958)、登海605(DH605)为试验材料,研究玉米籽粒形成过程中干物质积累、水分含量及内源激素含量变化。结果表明,早熟品种较晚熟品种灌浆期短,籽粒开始脱水早,脱水速率高,生理成熟期粒重低,产量低,但早熟品种中DH518的产量显著高于HZ8。不同熟期玉米品种籽粒内源激素含量及其变化模式不同,但同一激素含量随籽粒发育的变化趋势一致。两早熟品种籽粒的ABA含量高于两晚熟品种,尤其表现在灌浆中后期。各品种籽粒灌浆、脱水速率均与内源激素含量有关,两早熟品种的籽粒脱水速率与玉米素核苷(ZR)含量呈显著正相关。

Grain filling,dehydration characteristics and changes of endogenous hormones of summer maize hybrids differing in maturities

This study was expected to explore the relation of grain-filling and dehydration characteristics with changes of endogenous hormones of summer maize hybrids differing in maturities, providing theoretical references for mechanized harvest of grains, high-yield, high-efficiency production and breeding of summer maize hybrids in the Huang-Huai-Hai Rivers region. The early maturity hybrids Denghai 518 (DH518), Hengzao 8 (HZ8) and the late maturity hybrids Zhengdan 958 (ZD958), Denghai 605 (DH605) were used to measure changes of dry matter accumulation, water content and endogenous hormone content in the process of kernel formation. Compared with the late maturity hybrids, the early maturity hybrids had shorter grain-filling duration, earlier beginning of dehydration, higher dehydration rate, lower kernel weight at physiological maturity stage, and lower yield. but among the early maturity hybrids, DH518 had significantly higher yield than HZ8. The endogenous hormones content and their changes in different hybrids were different, but the trend that the same hormone changed with grain development was the same. The ABA content of the early maturity hybrids in grain was higher than that of the late maturity hybrids, especially in the middle-late grain-filling stage. Both grain filling and dehydration rate were related to endogenous hormone, the dehydration rate of the early hybrids was positively correlated with ZR content.