江苏省五十年代以来中籼稻品种产量及有关性状的演变

Evolution of Yield and Related Characters of Medium lndica Rice Cultivars in Jiangsu Since 1950s

五十年代以来,本省中籼稻产量翻了一番多,历经两次飞跃。一是从早期地方品种过渡到中期矮杆品种,增产80.04％;二是由中期矮杆品种过渡到杂交水稻,增产15.54％。产量因素的变化主要表现为每穗总粒数的增加,每穗总粒数与产量有较高的遗传相关,是产量提高的主导因素。植株高度呈高杆—矮杆—中矮杆—中杆的趋势变化。叶片的直立性、光合作用强度、根系活力、抗倒力及收获指数,中、近期品种均较早期品种明显提高。生物量的变化与稻谷产量的变化趋势一致。净同化率。分蘖力等变化不大。故今后中籼稻高产品种的选育,应以中杆大穗类型为主。

The yield, yield components, plant form and physiological characters of 22 typical cultivars of medium Indica rice selected in Jiangsu since the 1950s were evaluated in a randomized block design with 4 replications in 1987 and 1988. The yield of medium Indica rices in Jiangsu had been doubled since the 1950s. It was completed in two leaps-the first was transition from local varieties in the early period to short-stalked varieties of the middle period with a yield increase of 80.04 percent,and the second was from short-stalked varieties to hybrid rice with a yield increase of 15.54 percent. The increase in yield mainly resulted from the increase in total grains per spike which showes higher genetic correlation to yield. The height of stalk changed from high to short, to medium short, and to medium. Leaf erectness, photosynthe-ticrate, root vitality, lodging resistance and harvest index were higher in varieties of the middle and current periods than in varieties of the early period. The biomass yield changed in correspondence with the grain yield. The net assimilation rate and tillering ability showed little changes. The authors suggest that in selection of medium Indica rice cultivars, the medium stalk and big spike should be taken as goals.