Study On Changes Of Lopsided Fruit And Factors Lead To Lopsidedness Of Fruit In Korla Fragrant Pear

Korla fragrant pear(Pyrus sinkiangensis Yu), a cultivated variety in Korla, is well-sold in large and middle-sized city. And the price is twice higher than other varieties with a promising prospect. Recent years, lopsided fruit occurred repeatedly in Korla fragrant pear due to extreme weather and poor management. Therefore, in this paper, relationships among seed numbers, FSI(Fruit shape index), endogenous hormones, mineral elements and fruit quality were analyzed to explore the cause of lopsided fruit in Korla fragrant pear. Results as follows:1. The study on the seed numbers and FSI indicated that there was a significant correlation between seed numbers and fruit shape index(-0.51**). And an exponential relationship(y=0.3928e-0.153 x R2=0.2223) was found between seed numbers and FSI.2. In the young period of developing fruit, significant differences of endogenous hormones and mineral elements content were observed with the decreasing of pollinated numbers of stigma. The distribution of GA3 in small and large part of lopsided fruit was significantly different compare with CK. Significant differences of ZT content were also observed among the pollination treatments.Nitrogen and phosphorus in small part of lopsided fruit were significantly higher than those in large part.3. In the harvest period, the GA3,IAA and ABA content were decreased along with the increased numbers of seed, and the concentration gradient was also observed between mesocarp and endocarp of lopsided fruit. Distribution of nitrogen, phosphorus, magnesium and calcium were in accordance with the model that high in endocarp, low in mesocarp and high in exocarp. Whereas the distribution of potassium was high in endocarp, middle in mesocarp and low in exocarp.4. In the harvest period, sugar acid ratio in small part of lopsided fruit significantly was lower than that in large part. To evaluate the fruit quality of lopsided fruit, subordinate function was used to rank the small and large part of lopsided fruit which classified based on the numbers of seed. The results indicated that the fruit quality of small part was also significantly better than the large part of lopsided fruit.5. In the young period of developing fruit, the(IAA+GA3+ZT)/ABA ratio of lopsided fruit was siginificantly lower than CK, which indicated that the young fruit period was the critical period of the formation of lopsidedness. And FSI as well affected the maturation process by affecting endogenous hormones, mineral elements.