| Maize is China’s first major grain crops, the yield is related to national food security. The shortage of phosphorus removal seriously limits the improvement of maize yield. Low content of available P in soil is more than just the problems existing in the China, but the global widespread publicity. Screening and breeding efficiency of phosphorus absorption and utilization of crop varieties, are effective measures to solve the effective phosphorus content is low, is of great significance for agricultural production. In crop production is the basic way of solving phosphorus deficiency using genetic differences of crops to low phosphorus tolerance itself, by the method of genetic breeding improvement, make its P nutrient cycle improvement, its purpose is to better in the future application of low phosphorus tolerance maize germplasm resources, make the low phosphorus tolerance maize inbred lines and the selection and breeding of new varieties of strategies according to the can depend on, and has practical operability. The results of the study are as follows:1 Genetic analysis of maize inbred lines above ground traits of low phosphorus tolerancePhosphorus deficiency symptoms of leaf number of heritability is given priority to with rate of polygenic inheritance. Choice of low phosphorus resistant material the highest efficiency in the F2 generation. Each group of genetic variation accounts for 49.35%～77.13% of phenotypic variation, environmental variation accounts for 22.87%～50.65% of phenotypic variation, greatly influenced by the environment on the symptoms of low phosphorus leaf, rely on symptoms choose low phosphorus tolerance material is not accurate.Genetic of plant height is two pairs of additive-dominant-epistatic gene+lord additive dominant genetic control, two interactions of dominant effect genes of god is greater than two interactions of main gene additive effect. The B2 choose the highest efficiency. Each group of genetic variation accounts for 78.42%～84.32% of phenotypic variation, environmental variation accounts for 15.78%～21.58% of phenotypic variation, the influence of environment on plant height under low phosphorus condition is also small.Leaf area of heredity is two pairs of additive-dominant-epistatic main gene+additive dominant polygenic control, main gene additive effect of low phosphorus tolerance its positive effect, resistance to low phosphorus material in B2 generation selection efficiency is highest. The population genetic variation accounts for 82.90%～84.45% of phenotypic variation, environmental variation accounts for 5.55%～7.10% of phenotypic variation, under the condition of low phosphorus environment has little effect on leaf area.2 Genetic analysis of maize inbred lines root traits of low phosphorus toleranceThe total root length by additive-dominant-epistatic genetic control. Choose the highest efficiency in F2, the genetic variation of phenotypic variation was 30.98% on average, environmental variation of phenotypic variation was 69.02% on average, the environment of plant a greater influence on the total root length.Root volume by two pairs of additive-dominant-epistatic main gene+additive-dominant polygenic control. Two interaction of dominant effect genes of god is greater than two interactions of main gene additive effect. Select material resistant to low phosphorus efficiency is highest in B2, under the condition of low phosphorus environment the influence of the root volume is small.Root volume by two pairs of additive-dominant-epistatic main gene+additive-dominant polygenic control. Has a positive effect, the main gene additive effect plays a role of negative dominant effect, in F2 choose the highest efficiency, under the condition of low phosphorus environment has little effect on the root surface area.Root dry weight of the two pairs of additive-dominant-epistatic main gene+more control. Low phosphorus in B2 on materials selection choose the highest efficiency, environment influence on root dry weight is smaller.The roots of phosphorus content in genetic by two pairs of additive-dominant-epistatic main gene+more control. Main gene additive effect has a positive effect on the roots of phosphorus content of genetic, dominant effect on root phosphorus genetic negative effect. In B2 choose the highest efficiency, under the condition of low phosphorus environment root P content is less affected.3 Genetic analysis of inbred lines of dry matter weight and P uptake of low phosphorus toleranceGenetic by two pairs of the dry weight of the above ground additive-dominant-epistatic gene+more control, has a positive effect the main gene additive effect, dominance effect of negative effect. The main gene+polygene heritability were 79.90%,87.76% and 82.17%, in B2 generation to choose the best effect. Each group of genetic variation accounts for 74.18% ～86.22% of phenotypic variation, environmental variation accounts for 13.78%～25.82% of phenotypic variation, environmental impact on the low phosphorus condition of the dry weight of the above the upper is lesser also.Genetic by two pairs of aboveground phosphorus additive-dominant-epistatic main gene +additive dominant polygenic control, two of the main dominant effect genes interactions significantly greater than two interactions of main gene additive effect. In the F2 choose the highest efficiency. Each group of genetic variation accounts for 69.68%～86.34% of phenotypic variation, environmental variation accounts for 13.66%～30.32% of phenotypic variation, environment of low phosphorus condition above the upper has little effect on phosphorus content.Genetic phosphorus use efficiency by 1 additive primary gene+additive-dominant polygenic control model. Many genes has a positive effect on phosphorus use efficiency, dominant effect is bigger than the effect of additive effect. Phosphorus use efficiency of the main genetic rate was the highest in F2, the highest rate of polygenic inheritance with B2, 41.86. Each group of genetic variation accounts for 20.50%～44.56% of phenotypic variation, environmental variation accounts for 59.49%～79.50% of phenotypic variation, so the influence of environment on phosphorus use efficiency.4 Genetic analysis of maize yield characters of low phosphorus toleranceSpike kernel weight of the two main gene additive, dominant and additive by additive, dominance x dominant and additive x dominant effect. Its main gene+ polygene heritability were 43.87%,66.07% and 26.29%, respectively. Each group of genetic variation accounts for 23.61%～65.22% of phenotypic variation, environmental variation accounts for 35.53%～69.55% of phenotypic variation, under the condition of low phosphorus environment influenced by the spike grain weight.For the genetic characteristics of grain weight analysis, there is no genetic model to find the right, this may be related to detection method to detect 3 for the existence of the main genes. |
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