Studies on ecological adaptability and suitable planting area of a two-line hybrid rice, liangyoupeijiu

Chinese. 【目的】实现两系超级稻两优培九大面积种植,分析其生态适应性,合理规划和选择最适宜种植区域。【方法】在南方稻区8个试验点连续2年进行区域生态适应性试验。根据水稻生长发育和产量形成与种植环境相协调一致的原理,采用生长解析方法,选择生育期（GD）、生长速率（GR）、灌浆速率（FR）和产量指数（YI）为分析要素,分析两优培九在中国南方稻区的适应性。【结果】GD、GR、FR都可以建立决定系数较高的环境模型,YI可以由GD、GR、FR综合表达。两优培九出穗的高温促进率,短日下为5级,长日下为3级,短日促进率为4～5级,为中等感光型,在华南双季稻区的生育期稳定性低于长江中下游稻区及江淮稻区。GR等值线呈东南-西北走向,与该地区的夏季温度分布基本一致。长江中下游稻区和江淮稻区是GR距平＋10%的高值区,华南双季稻区为距平负值区。FR除了受灌浆结实期的环境影响外,还受到抽穗前积累的干物质量（GW）运转的影响。FR等值线基本呈纬向分布,距平-20%线在24°N以南,大致与两优培九作双季连作稻种植的北界一致。24～28°N为FR距平负值区域,28～30°N为FR距平正值区域,距平＋20%区域在江淮稻区。因地势特点,GR和FR在四川盆地及洞庭湖地区有相对低值区,在云贵高原河谷和湘、黔、川交界的低山丘陵有相对高值区。两优培九YI在南方稻区自南向北递增,平均达到（10.01±2.71）t・ha-1。其中,华南双季稻区为（7.31±1.00）t・ha-1,华中单双季稻区为（9.34±1.28）t・ha-1,长江中下游和江淮稻区为（11.93±2.04）t・ha-1,洞庭湖地区和四川盆地是7.5～9.0t・ha-1的低YI区,云贵高原河谷地区有15t・ha-1以上的生产潜力,南方丘陵也有10.5t・ha-1的高YI区。【结论】在种植区规划上,两优培九宜作为一季中稻,继续向28～30°N华中单双季稻区北部最有利的生态区域发展。

English. [ Objective] To learn the ecological adaptability of the two-line hybrid rice, Liangyoupeijiu and plan its suitable planting areas, [Method] An experiment for environmental adaptability was carried out in 8 plots in South China rice growing areas in 2006 and 2007. According to the correspondence between rice growth and yield to environmental conditions, by growth analysis, the growth duration （GD）, growing rate （GR）, grain filling rate （FR） and yield index （Y/） were chosen as factors to analyze. [Result] The results showed that, GD, GR, FR could be simulated by such factors, and the YI could be effectively described by GD, GR and FR. The sensitivity described by promoting rate of heading date which was caused by photo-thermo, were middle grade as 4-5, and the stability of GD was high in middle and lower reaches plain of the Yangtze River and Huai River valleys than in the double rice cropping areas in South China. The isoline of GR showed same as the distribution of temperature, and the higher one by ＋10% than average were in the middle and lower reaches plain of the Yangtze River and Huai River valleys, and showed minus in double rice cropping areas in South China. FR was affected by environmental conditions at filling stage and the dry matter weight （GW） accumulated before heading. The isoline of FR showed distribution in latitude, and the distribution of-20% than average was southern of 24°N, same as the northern limit line of its planting area as double cropping area. Minus areas were in 24-28°N, and positive areas were 28-30°N, and ＋20% of average were in single rice cropping area around Huai River. Besides, there were GR and FR lower areas in Sichuan and Dongting basins, and higher areas in valley of the Yangtze River in Yunnan and hills marching with Hunan, Guizhou and Sichuan Provinces. The YI showed higher along with latitude with its average of （10.01±2.71） t.ha-1. Among them, Y1 showed （7.31±1.00） t.ha-1 in South China, and （9.34±1.28） t・ha-1 in single or double rice cropping areas in Central China, and （11.93±2.04） t.ha. 1 in middle and lower reaches plain of the Yangtze River and Huai River valleys. There were lower YI as 7,5-9.0 t-ha. 1 in Sichuan and Dongting basins, and high YI as 15 t.ha~ in valley of the Yangtze River in Yunnan, and about 10.5 tha. in hills of South China. [ Conclusion ] Thus, the most suitable areas were between 28-30°N, and the hybrid would fiarthest showed its growing and yield potential there.