Identification of Low-Phosphorus-Tolerance in Dongxiang Wild Rice(Oryza rufipogon Griff.)

Excavation and utilization of advantageous genes in wild rice resources are one of the current hot points in the research on rice crop.With the cultivated low-phosphorus-tolerance rice varieties Dalidao and Liantangzao3,low-phosphorus-sensitive varieties Xingsanbaili and Huzhanqi,hybrid rice fertility retaining line XieqingzaoB as the control,the low-phosphorus-tolerance ability of Dongtangxia population of Dongxiang wild rice at the seedling stage was identified through Yoshida nutrition solution cultivation with five phosphorus concentration levels,i.e.10,5,3,0.5,0 mg/L.The indexes of plant height,leaf age,yellow leaves,the stem width,root numbers per plant,length,width and open angle of the second leaf from top,dry weight of the shoot and root were measured at the stage of five-leaf-and-one-leaflet period.The results showed that the suitable concentration for low-phosphorus-tolerance ability identification was 0.5 mg/L,while the suitable simple indexes were relative leaf age and yellow leaf ratio.The relative leaf age values(ratio of 0.05 mg/L by 10 mg/L) of Dongxiang wild rice Dongtangxia population,Dalidao,Liantangzao3,Xingsanbaili,Huzhanqi,and XieqingzaoB were 0.947 8,0.996 6,0.954 9,0.873 7,0.822 5,and 0.828 2;the yellow leaf ratios were 0.35,0.49,0.66,0.67,0.67,and 0.68,respectively.Viewed synthetically Dongtangxia population has strong low-phosphorus-tolerance ability.