Abstract:

In order to screen out the appropriate mechanical direct seeding combinations of double cropping early and late rice, 12 early rice varieties and 14 late rice varieties （combinations） were comparison tested in Dongting Lake area. The results showed that, the early-season rice varieties were direct-seeding before April 1st, which could emerge safely and mature before July 15th, the yields of Zhongzao 39, Luliangyou 996 and Zhuliangyou 211 were higher, and achieved 8.25 t/hm2, 7.75 t/hm2 and 7.30 t/hm2 respectively. The late-season rice varieties were direct-seeding before July 19th, most of the cultivars could be full-heading before September 15th and mature before October 31th, the yields of Qiliangyou 007, Zhongzao 39 and Luliangyou 996 were higher, and achieved 7.23 t/hm2, 7.00 t/hm2 and 6.94 t/hm2 respectively. The study indicated that Zhongzao 39, Luliangyou 996 and Zhuliangyou 211 as early rice, together with Qiliangyou 007, Zhongzao 39 and Luliangyou 996 as late rice, were the appropriate combinations for the double-season mechanical direct seeding in Dongting Lake area. It was the apporiate period of direct seeding early rice before April 1st. It was the appopriate period of direct seeding late rice before July 20th.

Key words: double season rice, mechanical direct seeding, rice variety screening, Dongting Lake area

摘要：

为筛选出适宜的早、晚稻连作机直播搭配品种，在洞庭湖区选用12个早稻品种、14个晚稻品种作试验材料，进行了双季机直播对比试验。结果表明，4月1日机直播早季各品种均能安全出苗，且能于7月15日前成熟，其中，中早39、陆两优996和株两优211的产量较高，分别达8.25 t/hm2、7.75 t/hm2和7.30 t/hm2；晚季于7月19日机直播，大部分品种能在9月15日前齐穗，10月31日前成熟，以柒两优007、中早39和陆两优996产量较高，分别达7.23 t/hm2、7.00 t/hm2和6.94 t/hm2。综上，早季中早39、陆两优996、株两优211，搭配晚季柒两优007、中早39、陆两优996是洞庭湖区双季机直播的适宜组合，早、晚季最佳安全机直播期分别为4月1日前和7月20日前。

关键词: 双季稻；机直播；品种筛选, 洞庭湖区