高原粳稻温光生态特性的梯度变化

 采用大田分期播种和盆栽延长光照的试验,研究了川西南西部高原面和宽谷区粳稻品种的抽穗开花温光生态特性.结果表明,不同海拔粳稻品种的感温性、感光性及开花习性等表现明显的梯度变化.粳稻品种播种至出穗天数与总和温的关系符合y=a+bx的线性关系,由此导出各海拔类型品种生物学起始温度和有效积温的置信区间.品种原产地海拔越高,生物学起始温度越低,感光性更弱,开花历时越短,花期更集中,强势粒率越高.

The Gradient Variation of the Thermal- and Photoecological Characteristics on Plateau Type Kent Rice

The thermal-photo responses of various kinds of keny typical rice (Oryza sative subap. Keng Ting) to temperatures and photoperiod were ivestigated under field culture and pot culture conditions at different altitudes. The 20 varieties of keny rice from Southwestern Sichuan plateau ridge valley were used, and the altitudes of plateauⅠ, plateauⅡ, plateauⅢ and River valley varieties were 2 510～2 670, 2 450～2 500, 2 250～2 400 and 1 500～1 650 m, respectively. The results indicated that the thermaland photo-ecological characteristics of keny rice varieties at different altitudes showed apparent gradient variations. The relationships between days and accumulated temperature from seeding to heading of keny rice could be determined by the linear regression equation: y=a+bx, The thermal-photo responses of keny rice to temperature and photoperiod would gradually decrease alone with the increase in altitude. The higher the altitude of varieties' origination, the less the days of flowering duration and the higher the rate of strong potential grain was. When the altitude of varieties' orgination rose each 100 m, the days of flowering duration decreased about 3 days, and the rate of strang potential grain increased about 13%.