2016和2017年,以MC812和郑单958为试验材料,研究其籽粒灌浆和脱水特性。结果表明：(1)百粒干物重在品种间存在显著差异,MC812平均百粒干物重较郑单958高2.64 g,增幅为8.04%。(2)与郑单958相比,MC812籽粒达到最大灌浆速率的时间(Tmax)平均提前4.40 d、灌浆起始势(R0)高0.25、活跃灌浆期(P)长1.33 d；MC812灌浆渐增期的平均灌浆速率显著高于郑单958,灌浆缓增期则与郑单958相当。(3)生理成熟期和收获时的籽粒含水量在品种间存在极显著差异,MC812生理成熟时的籽粒含水量较郑单958高1.55个百分点,收获时的籽粒含水量则较郑单958低4.05个百分点；生理成熟前、后的脱水速率在品种间存在极显著差异,MC812分别较郑单958高0.30 %/d、0.14 %/d。(4)穗粒数、百粒重和产量在品种间存在极显著差异,MC812产量较郑单958高6.67%、穗粒数和百粒重分别较郑单958高8.56%和8.04%。由此可见,穗粒数多且籽粒灌浆启动早、活跃灌浆期长、前期灌浆速率高、脱水速度快是MC812较郑单958可获得较高产量且收获时籽粒含水量较低的主要原因。
英文摘要:
Field experiments were conducted in 2016 and 2017 to study the grain filling and dehydration characteristics of MC812 and Zhengdan958(ZD958). The results showed that, (1)100-grain dry weight differed significantly among varieties. The average 100-grain dry weight of MC812 was 2.64 g higher than that of ZD958 increased by 8.04%. (2)The time reaching the maximum grain filling rate (Tmax) of MC812 was 4.40 d earlier, the grain filling initiation potential (R0) was 0.25 higher and the grain filling duration (P) was 1.33 d longer than ZD958; the average filling rate during gradual increasing period of grain filling for MC812 was significantly higher than that of ZD958, and the average filling rate during slow increasing period of grain filling was the same. (3)The grain moisture content at physiological maturity and harvest differed significantly among varieties, the moisture content of MC812 was 1.55 percent higher at physiological maturity and 4.05 percent lower at harvest than ZD958; differences of the dehydration rate before and after physiological maturity were extremely significant among varieties with 0.30 %/d and 0.14 %/d higher of MC812 than ZD958. (4)Differences of the grain number per ear, 100-grain weight and yield were extremely significant among varieties; the yield of MC812 was 6.67% higher, the number of grains per ear and 100-grain weight were 8.56% and 8.04% higher than ZD958, respectively. Thus, higher grain number per ear, initial grain filling potential and grain filling rate during the earlier grain filling period, longer active grain filling period, faster dehydration rate of MC812 were the main reasons for the higher grain yield and lower moisture content at harvest than ZD958.
;
