双季机插稻不同产量水平群体的产量构成特征研究

为明确双季机插稻产量构成特征及高产协同规律,促进双季稻机插栽培技术的发展,以4个早稻(株两优30、两优287、中嘉早17和中早35)和4个晚稻(H优518、五丰优T025、五优308和天优华占)品种(组合)为试验材料,研究双季机插稻中产(7 000~8 250 kg·hm^-2)、高产(8 250~9 000 kg·hm^-2)和超高产(>9 000 kg·hm^-2)3个产量水平群体的产量及产量构成特征。结果表明,随着双季机插稻产量水平的提高,有效穗数、每穗粒数和总颖花量均呈显著增加的趋势,结实率和千粒重总体上差异较小;产量与群体总颖花量呈极显著正相关,要实现9 000 kg·hm^-2以上的产量,每平方米颖花量需达到42 000以上;从中产到高产,双季早晚稻总颖花量的增加均主要依靠穗数的增加,从高产至超高产,早稻总颖花量的增加仍可以通过适当增加穗数实现,而晚稻总颖花量的增加应在适当增加穗数的基础上提高每穗粒数。以较多的穗数和较大的穗型协同产出较高的总颖花量,同时保证正常的结实率和千粒重,是双季机插稻超高产基本特征。本研究结果为双季机插稻高产栽培提供了理论依据与实践参考。

Characteristics of Yield Components From Middle-yield to Super-high-yield of Machine-transplanted Double Rice

To accelerate the development of mechanical transplanting cultivation techniques of double rice, field experiments were conducted to study the characteristics of yield and yield components among three types of populations (super-high-yield:>9 000 kg·hm^-2, high-yield: 8 250~9 000 kg·hm^-2, middle-yield: 7 000~8 250 kg·hm^-2) under mechanical transplanting, with four combinations of early rice (Zhuliangyou30, Liangyou287, Zhongjiazao17 and Zhongzao35) and four combinations of late rice (Hyou518, WufengyouT025, Wuyou308 and Tianyouhuazhan). The results showed that, the panicles, grains per panicle and total spikelets all increased significantly with the increase of yield level, while there was no significant difference in filled grain percentage and 1000-grain-weight. Significant positive linear correlation was existed between the total spikelets and grain yield. The total spikelet number should be greater than 42 000 per m²as yield was above 9 000 kg·hm^-2. In order to enlarge the total spikelets of double rice, it mainly depended on enriching panicles from middle-yield to high-yield. From high-yield to super-high-yield, the enlarging of total spikelets of early rice can be realized by enriching panicles appropriately, and increasing grains per panicle on the basis of enriching panicles appropriately was an important approach to enlarging total spikelets of late rice. The basic characteristics of super-high-yielding machine-transplanted double rice were enriching the amount of total spikelets by obtaining more and bigger panicles and keeping normal filled grain percentage and 1000-grain-weight. The study provids theoretical and practical basis for mechanized transplanting technology of double rice.