A Preliminary Study On Tolerance Of Different Maize Genotype Under Low-phosphorus Stress

Phosphorus is a basic nutrient for plant growing, deficient phosphorus is dangerous to maize yield and quality . In our country and even the world, as a result of the phosphorus special physics and chemistry nature, it had decided the fact that the soil entire phosphorus content is high, and available phosphorus is deficient .Most available phosphorus in fertilizer could be changed into fixed types witch cann't be absorbed by plant . The fixed phosphorus don't meet the need of plant living because its solubility is very low, so this fact is called the Genetics Lack, but not the Soil Lack. The soil has stored up rich phosphorus. Two ways can enhance the phosphate fertilizer efficiency: One is to improve soil for the phosphorus condition, namely through reforming the soil and rational fertilizing to enhance the soil phosphorus validity; Another is to improve abilities of crops for using phosphate fertilizer, namely through the heredity breeding methods to develope crop varieties which can fully use the soil phosphorus (including slow effect phosphorus and difficult dissolving phosphorus). Comparing the two ways above, the later is better.80 maize inbred lines and some F1 hybrids were identified for tolerance to low-phosphorus in two ecotopes of Sichuan province,which the effective phosphorus content in soil is deficient. The mean, variation range, variation coefficient for coefficient of tolerance to low phosphorus in some biological traits and the correlation between the traits were analyzed. The results showed that in low-phosphorus condition corn inbred lines and hybrids were remarkably variable among genotypes. The variance range of low-phosphorus tolerance was the potential for breeding low-phosphorus tolerance varieties.Based on the result of identifying maize tolerance for low-phosphorus, 10 inbred lines...