迟播迟栽对不同类型粳稻品种机插产量及生育期的影响

以杂交稻和常规稻为试验材料,在苏南常熟、苏中兴化和苏北东海3个试验点同时开展播期试验,探讨迟播迟栽条件下机插稻稳产、增产问题。结果表明,随着播期的推迟,各试验点水稻生物产量、经济产量、经济系数、单位面积穗数、每穗粒数、群体颖花量和结实率不断下降,生育期延迟且全生育期缩短。分析发现,每穗粒数受播期影响最大,其余依次为结实率、穗数、千粒重。甬优2638依其大穗优势具有更高的产量潜力,但随着播期的推迟,其产量优势减小。甬优2638在各稻区均表现出抽穗较早、群体库容大、生物产量高等优势,具有在迟播迟栽生产条件下获取稳产、高产的潜质。迟播迟栽对不同类型水稻品种产量及生育期具有较大影响。据此,从安全生育性及稳产角度考虑,对不同类型品种在不同稻区生产的最晚播期进行了初步拟定,以为大面积生产提供参考。

Effect of Late Sowing and Late Transplanting on Yield and Period of Duration of Different Types of Mechanical Transplanting Rice

A comparative study of the effects of late sowing and late transplanting on yield and formation of mechanical transplanting rice was conducted through setting five sowing dates based on the production conditions in the following three different regions： Taihu rice district in Changshu （Sunan）, Lixiahe rice district in Xinghua （Suzhong）, Huaihei rice district in Donghai （Suhei）, with hybrid rice and conventional rice as materials. The results showed that along with the delayed sowing date, the biomass yield, actual yield, harvest index, No. of panicles, No. of spikelets per panicle, total spikelets, seed-setting rate declined, and the whole period of growth and development shortened. Analysis revealed that sowing date showed greatest influence on No. of spikelets per panicle, then seed- setting rate, panicles and 1000-grain weight. The hybrid rice Yongyou 2638 exhibited higher yield advantage and potential through its large spike. But with the delay of sowing date and exaltation of latitude, the yield advantage of hybrid rice minified. Therefore, if there is no any production potential in the variety under the production mode of late sowing and late translating, a latest sowing date should be concluded, based on the variety characteristic and the phonological conditions, from the perspective of cultivating safe and stable yield. Some conclusions about the most late sowing date of the tested varieties was tentatively set in this paper, in order to provide a reference for the large scale production.