超迟夏直播常规粳稻品种（系）的适应性筛选

Adaptability Screening of Conventional Direct-Seeding Japonica Rice Varieties(Lines) in Ultra-Late Summer

为川东丘陵区及相似生态区油菜(小麦)收获后水稻直播栽培品种的确定提供理论依据和生产参考,对12个常规粳稻品种(系)进行超迟夏直播(正常播种时间为5月10左右,试验播种时间为6月7日)大田试验,研究超迟夏直播常规粳稻的生育进程、分蘖成穗特性和产量表现。结果表明,超迟夏直播条件下,参试品种在10月5日前均能成熟,全生育期为109~121d,平均113d;产量为330.1~526.6kg/667m^2,平均439.6kg/667m^2;有效穗数为13.4万~22.0万穗/667m^2,平均17.9万穗/667m^2,有效穗组成比例为一次分蘖穗>二次分蘖穗>主茎穗;产量与有效穗呈显著正相关,与穗粒数和穗实粒数呈极显著正相关,与结实率和千粒重呈正相关;德粳2号、德粳9号和德粳11号3个粳稻品种(系)超迟夏直播的产量高于500kg/667m^2,适宜川东丘陵地区油菜(小麦)茬延后直播种植。

The purpose of this study was to provide theoretical basis and production references for the confirmation of conventional delayed direct-seeding japonica rice varieties with rape(wheat)stubble in hilly areas in the east of Sichuan and similar ecological areas,twelve conventional japonica rice varieties were selected for field experiment of ultra-late summer direct seeding on June 7(normally on May 10)to study the growth process,panicle structure and yield performance under ultra-late summer direct seeding.Results:12 conventional japonica rice varieties could mature before October 5,and the whole growth period was 109-121 days,113 days on average.The yield of 12 conventional japonica rice was 330.1-526.6 kg/667 m^2 under direct seeding in late summer,with an average of 439.6 kg/667 m^2.The effective panicles per 667 m^2 ranged from 134 000 to 220 000,with an average of 179 000.The effective panicles consisted of primary tiller panicle > secondary tiller panicle > main stem panicles.The yield is significantly related to effective panicle positively,very significantly related to grains per spike and filled grain number per panicle positively,related to setting rate and 1000-grain weight positively.Therefore,Dejing 2,Dejing 9 and Dejing 11 are conventional japonica rice varieties suitable for rape(wheat)delayed direct seeding in hilly areas in the east of Sichuan,the yield of them are over 500 kg/667 m^2.