栽培密度对不同生育时期水稻品种产量影响的研究

目的]为不同生育期的水稻确定高产栽培适宜的种植密度。方法]设置9.00万、13.50万、17.25万、22.50万、25.65万、32.10万窝/hm26个栽培密度,研究长生育期宜香481(P1)、短生育期101A/R1007(P2)的茎蘖动态及产量。结果]随着密度的下降,P1分蘖高峰期的每窝水稻分蘖数量相应增加。P2的分蘖数量稀植时较多,密植时较少。随着密度的增加,两个品种的最高分蘖期提前,单株有效穗数降低且呈简单直线相关。P1在密度17.25万窝/hm2时有效穗数最高,达241.20万/hm2,产量最高,达10281.6kg/hm2;P2在密度22.50万窝/hm2时有效穗数最高,达277.05万/hm2,产量最高,达9631.5kg/hm2。每穗实粒数对P1的产量影响最大,其次是有效穗数;增加有效穗数能显著增加P2的产量。结论]生育期长的品种相对稀植有效穗数才理想,生育期短的品种适当加大种植密度有利于提高有效穗数。

Influences of Planting Density on the Yield and Its Composing Factors of Two Rice Varieties

Objective] The aim of the study was to confirm suitable planting density of high-yield cultivation for rice with different growth periods. Method] 6 planting densities of 90 000, 135 000, 172 500, 225 000, 256 500 and 321 000 nests/hm2 were set up to study the tillering dynamics and yields of Yixiang 481 (P1) with long growth period and 101A/R1007 (P2) with short growth period. Result] Along with the decrease of density, the rice tiller quantity per nest increased correspondingly in tillering peak stage of P1. The tiller quantity of P2 planted thinly was more and that of P2 planted thickly was less. Along with the increase of density, the highest tillering periods of the 2 varieties advanced. Their available ear number per plant decreased and showed simple linear correlation. P1 got highest available ear number (241 200 0/hm2) and highest yield (10 281.6 kg/hm2) at 172 500 nests/hm2. P2 got highest available ear number (277 050 0/hm2) and highest yield (9 631.5 kg/hm2) at 225 000 nests/hm2. The full grain number per ear had biggest influence on the yield of P1 and available ear number was secondary. Increasing available ear number could increase the yield of P2 significantly. Conclusion] The variety with long growth period can get perfect available ear number under relatively thin planting. Properly increasing planting density for the variety with short growth period was in favor of enhancing available ear number.