论文部分内容阅读
本文选用1985~1996年间南方稻区区试早籼中熟组南昌点(北纬28°41’,东经115°58’)资料,以泸红早为对照,比较分析了历年产量居第一位的新品种(下称优秀品种)的主要农艺性状特征,结果为:a.12年中,优秀品种平均比对照增产6.5%,如除去两个减产年份,平均增产比例达8.5%;b.优秀品种全生育期平均比对照延长1.2d,生育期延长主要是灌浆期延长所致;c.优秀品种的株高平均增加2.3cm,分蘖率增加14.5%,而有效穗和成穗率分别下降2.1%、4.6%;d.穗部性状中,以单穗总粒数、实粒数、单穗重增长率较大,而结实率为负增长;e.各性状与产量间的正相关系数大小顺序为:结实率>单穗重>株高>单穗实粒数>成穗率>穗长>齐穗至成熟天数>千粒重>单穗总粒数>有效穗数,其中结实率达极显著相关,而分蘖率、播种至齐穗日数为弱的负相关。本文指出,结实率低和成熟率低是新育成的优秀品种进一步高产的限制因素,今后南方稻区早籼中熟种育种策略应是:适当增加株高;确保较高的、年份间较稳定的结实率;提高成穗率;在不增加全生育期的情况下,适当延长灌浆期;通过增加单穗总颖花数以达到增加穗重,最终实现高产的目标。
In this paper, we selected the data of Nanchang point (latitude 28 ° 41 ’north latitude, longitude 115 ° 58 ° longitude) of early indica rice Zhongqu group in southern rice region from 1985 to 1996 in comparison with that of Luhong early. Varieties (hereinafter referred to as excellent varieties) of the main agronomic traits, the results are: a. In the 12 years, the average annual output of excellent varieties increased by 6.5% compared with the control. For example, The average growth period of excellent varieties was 1.2 days longer than that of the control. The growth period was mainly due to the prolongation of grain filling stage. C. The average height of excellent cultivars increased by 2.3cm and the tillering rate increased by 14.5%, while the effective spike and ear percentage decreased by 2.1% and 4.6% respectively. D. In the panicle traits, the total grain number per panicle, the number of real grains, the rate of single panicle weight growth were larger while the seed setting rate was negative; e. The order of the positive correlation coefficient between the traits and the yield was: seed setting rate> single spike weight> plant height> number of single spike grain> percentage of spike> length of spike> number of spike to ripening days> grain weight> number of single spike> The number of effective panicles, of which the seed setting rate was extremely significant correlation, while the tillering rate, sowing to the heading date is weakly negative correlation. This paper points out that the low seed setting rate and low maturity rate are the limiting factors for the further high yield of the newly bred elite varieties. In the future, the breeding strategy of early maturing medium bred varieties in the southern rice area should be: to increase plant height properly; to ensure higher stability Of the seed setting rate; to increase the rate of ear formation; without increasing the full growth period, the appropriate filling period; by increasing the number of spike per spike to increase panicle weight, the ultimate goal of high yield.