Studies On The Genetic Difference Of Nitrogen And Phosphorus Utilization Efficiency In Winter Wheat Varieties

In order to study the genetic difference of N and P utilization efficiency among wheat varieties, the N and P contents in grain, leaf and stem were mensurated and the genetic cluster analysis was carried out for 137 wheat parents. At the same time, under two different conditions, the fertilizer and water deficiency and the normal condition, the genetic difference of N and P utilization efficiency among 29 common wheat varieties were studied. The main results were as follows:1.The results of genetic cluster analysis of N utilization efficiency showed that 137 wheat parents could be divided into three types. First type was including 38 parents,they were high-efficient parents; Second type was including 53 parents, they were low-abilitied parents in absorbing N; Third type was including 46 parents, they were low-efficient parents. The results of genetic cluster analysis of P utilization efficiency showed that 137 wheat parents could be divided into three types. First type was including 60 parents, they were low-efficient parents; Second type was including 53 parents,they were fertilizer-wasted parents; Third type was including 24 parents, they was low-efficient parents. There were 7 wheat parents whose N and P utilization efficiency were high.2.The genetic difference of N utilization efficiency in common wheat varieties were studied. The results showed that under the two different conditions, the average N content in grain was higher than that in leaf, and the average N content in leaf was higher than that in stem. The difference of N content in grain, leaf and stem among wheat varieties were significant. Under N fertilizer and water deficicency condition, the N utilization efficiency of wheat varieties was significantly higher than that under normal condition. Under the two conditions, the high-efficient or low-efficient wheat varieties were singled out. Under normal condition, the heritability of N content in grain, leaf and stem were 54.69%,52.21%,24.36%,respectively, and the heritability of N utilization efficiency was 44.45%;Under N fertilizer and water deficicencycondition, the heritability of N content in grain, leaf and stem were 45.98%, 30.48%, 17.41%, respectively, and the heritability of N utilization efficiency was 32.19%. The heritability of N content in grain and leaf and N utilization efficiency were high.3. The correlations between N utilization efficiency and relevant characters under the two conditions were studied. The results showed that under normal condition, the lower N content in leaf and stem, the more ear number and the higher 1,000 grains weight, so the higher N utilization efficiency; Under fertilizer and water deficiency condition, the higher N content in grain, 1,000 grains weight and spikelet dencity, the higher N utilization efficiency, reversely, the lower N content in leaf and yeld spikelet number, the higher N utilization efficiency, namely the higher N transported efficiency in plant.4. The genetic difference of P utilization efficiency in common wheat varieties were studied. The results showed that under the two different conditions, the average P content in grain was higher than that in leaf, and the average P content in leaf was higher than that in stem. The difference of P content in grain, leaf, stem and P utilization efficiency among wheat varieties were significant. Under normal condition, the P utilization efficiency of wheat varieties was significantly higher than that under fertilizer and water deficiency condition. Under the two conditions, the high-efficient or low-efficient wheat varieties were singled out. Under normal condition, the heritability of P content in grain, leaf, stem were33.89%,17.03%,4.37%,respectively, and the heritability of P utilization efficiency was 34.01%; Under fertilizer and water deficiency condition, the heritability of P content in grain, leaf and stem were 51.43%, 5.59%, 29.14%, respectively, and the heritability of P utilization efficiency was 34.82% .5.The correlations between P utilization efficiency and relevant ch...