Studies on Screening for Low-Phosphorus-Tolerating Genotypies and some Relative Physiological Traits of Sugarcane

It had evaluated tolerance of serveral sugarcane genotypes to low or no phosphorus supply, according to relative changes of biomass,by addition of nutrient solution with different level of phosphate( 1.0, 0.2,0.1,0.0 mMol/L in Hoagland solution) to sandy culture in pot trial;meanwhile,the changes of photosynthesis ability,inorganic phosphate concentration and acid phosphatase activity in leaves were also determined.The results showed that among those genotypes yuetang 57-423 and Badila have low tolerance to low or no phosphorus supply;yuetang 71-210,yuetang 85-177,yuetang 81-3254, guitang 1 have the highest tolerance; while yuetang 79-177,yuetang 63-237,taitang 172,new taitang 10 are moderate;taitang 134 could just adapted to low phosphorus condition.The net photosynthesis rate of unit leaf area didn't change significantly in most case but increase in some case and the total yield of photosynthsis of per leaf decreased with decreasing of phosphate supply,the later is not true in low-phosphorus-tolerating genotypies(i.e yuetang 71-210,yuetang 85-177).The concentration of inorganic phosphate is in steady-state,and activity of acid phosphatase enhanced with decreasing phosphate supply.