高产氮高效型籼稻品种的籽粒灌浆特性

为明确高产氮高效型籼稻品种的籽粒灌浆特性及其与产量和氮素利用的关系，选用高产氮高效型（HYHNE）、高产氮中效型（HYMNE）和低产氮低效型（LYLNE）杂交籼稻品种，在相应最适氮肥水平下，研究3种类型水稻品种籽粒灌浆特性差异及其与产量和氮利用效率的关系。结果表明，籽粒灌浆特性在不同类型品种间和不同粒位间均存在较大差异。强势粒的最大灌浆速率(GRmax)、达到最大灌浆速率时的米粒重(Wmax)和平均灌浆速率(GRmean)均表现为HYHNE>HYMNE>LYLNE，起始生长势(R0)、活跃灌浆期(D)和有效灌浆时间(T99)均表现为HYHNELYLNE>HYMNE， R0、D和T99均表现为HYHNE

Grain Filling Characteristics of the Rice Cultivar with High Yield and High Nitrogen Use Efficiency

In order to clarify the grain filling characteristics of indica rice varieties with high yield and high N use efficiency and their relationship with yield and nitrogen utilization, field experiments were conducted in 2014 and 2015, and hybrid Indica rice varieties with high yield and high nitrogen efficiency (HYHNE), high yield and medium nitrogen efficiency (HYMNE) and low yield and low nitrogen efficiency (LYLNE) were grown separately under their respective optimum N application amount to achieve maximum attainable yields. The differences of grain filling characteristics of rice cultivars in different types were investigated. The results showed that there were significant differences in grain filling characteristics among different cultivars and different grain positions. As for the superior grains, maximum grain-filling rate (GRmax), weight of a kernel at the time of maximum grain-filling rate (Wmax) and the average grain filling rate (GRmean) were all ranked in HYHNE > HYMNE > LYLNE; initial growth (R0), active grain-filling period (D) and effective filling time (T99) were all performed as HYHNE < HYMNE < LYLNE. However different tendency was found in inferior grains, their characteristics of GRmax, Wmax and GRmean were all performed as HYHNE > LYLNE > HYMNE, characteristics of R0, D and T99 were all performed as HYHNE < LYLNE < HYMNE. It was suggested that the cultivar of HYHNE had the characteristics of earlier grain filling initiation, faster filling rate and shorter effective filling time, regardless of grain position. The superior grains of cultivar of HYMNE filled well, but the inferior grains had the latest grain filling initiation, the slowest filling rate and the longest effective filling time. The filling characteristics of inferior grains might be the important reason limiting the further improvement of nitrogen efficiency in HYMNE cultivars.