Ecological Difference And Ability For Activating Unavailable Soil Phosphorus In Core Collection Of Yunnan Rice (Oryza Sativa L.), China

The ecological difference and activating characteristic of ineffective phosphorus of 608 accessions core collection (including 548 accessions landrace and 60 improved varieties) from 5 rice regions and 16 prefectures in Yunnan Province were evaluated when planted in P-deficient (effective P: 0.02 mg/kg) and P-sufficient (effective P: 80 mg/kg) acid red soil.(1) Correlation between 18 relative morphological characters of 548 accessions landrace core collection and index-trait of tolerance to low-P(RTDW) showed: 14 correlation of 18 characters were greatly significant and RSDW,REPN and RNT were abled to use for the subsidiary indexes to identify and screen genotypes with ability of activating ineffective phosphorus of Yunnan rice landrace.(2) Ability of activating ineffective phosphorus of rice landrace shows zonal distribution-increasing from the genetic diversity-center to the north. Accessions landrace from Northwest Yunnan cold highland japonica rice region and Northeast Yunnan highland japonica rice region had a more stronger ability of activating ineffective phosphorus,and that of South Yunnan single/double season rice region and South marginal paddy-upland rice region was strong and greatly different, with the diversiform distribution; Central Yunnan single season japonica-indica region was the relatively poor region. As far as prefecture, accessions landrace of Wenshan,Dehong,Lincang,Lijiang,Zhaotong had the most strongest ability of activating ineffective phosphorus , and that of Xishuangbanna,Nujiang,Chuxiong,Yuxi and Qujing was next, but that of Kunming,Dali,Honghe,Baoshan,Diqing was the poorest. cultivarswih strong tolerance to low phosphorus from the genetic diversity-center was the most.(3) Ability of activating ineffective phosphorus of rice landrace was stronger than that of improved varieties, confirming that the activating characteristic of ineffective phosphorus has based on the co-evolution between core collection and low-P or ineffective phosphorus stress from acid red soil in the long time.(4)Ability of activating ineffective phosphorus of Yunnan rice landrace is nearly correlated with the allelic number of SSR-RM190. The rice with the more allelic number of SSR-RM190 has the stronger ability of activating ineffective phosphorus.