Research On Planting Effect Of Green Fertilizer In Xinjiang Fragrant Pear Orchard Based On Fruit Quality Evaluation Index After Picking

The nutrient supplement of traditional pear orchards in Xinjiang mainly depends on chemical fertilizers.Excessive use of chemical fertilizers will lead to poor fruit,decreased soil fertility and deterioration of ecological environment.Poor orchard management mode seriously restricts the sustainable and healthy development of pear industry.Therefore,planting green plants in orchards for fertilization can not only reduce the application amount of chemical fertilizers,but also improve the fruit,which is conducive to improving the reputation and economic benefits of pear brands,and is an effective solution to this problem.In this study,the green manure planting experiment was carried out in the pear orchard.The green manure was planted between the pear trees,and the agricultural machinery equipment was used to crush the green manure into the soil for fertilizer during the flowering period.According to the different families and genera of green manure,four kinds of green manure planting modes were set up in the experiment,including leguminous green manure(alfalfa),gramineous green manure(oat),cruciferous green manure(rape)and orchard autochthonous green manure(autochthonous grass).Based on fruit quality indicators,a comprehensive evaluation model of fruit quality was constructed to explore the effects of different types of green manure on fruit quality of Korla fragrant pear.In addition,this study also explored the quality changes of pear fruit after planting green manure during different harvest periods and storage periods,aiming to provide corresponding theoretical basis for the time nodes of fruit harvest period and postharvest preservation and transportation under the green management planting mode of pear orchard.The main results are as follows:(1)Three years of green manure planting experiments showed that compared with the orchard grass green manure,the soluble solids content,protein,vitamin C and fruit hardness of the pear treated with legume green manure(alfalfa)were 9.57%,13.64%,44.03%and 30.97%higher,respectively.The single fruit weight of the pear treated with gramineous green manure(oat)was 7.48%higher,and the sugar acid ratio of the pear treated with cruciferous green manure(rape)was increased by 22.08%.Based on the results of principal component analysis,a comprehensive evaluation model of fruit quality was established.The comprehensive scores of quality were ranked as follows:leguminous green manure(alfalfa)>gramineous green manure(oat)>cruciferous green manure(rape)>orchard grass green manure.(2)On the basis of three years of green manure planting experiment,the leguminous green manure(alfalfa)with the best effect on improving the comprehensive quality of fruit and the self-growing grass green manure pear fruit with low management cost were selected for storage experiment.The results showed that during the whole storage process,the weight loss of pears treated with orchard grass green manure was less,and the fruit hardness of leguminous green manure(alfalfa)decreased most significantly at 20℃storage environment,which was 49.82%lower than the initial value of harvest.The comprehensive quality score of fragrant pear with alfalfa green manure decreased significantly at the later stage of storage at 15℃.Under the storage environment of 0℃,the weight loss of fragrant pear was the lowest,and it was beneficial to maintain the fruit hardness and nutritional value content.The change trend of fruit quality comprehensive score of two green manure treatments was basically the same.(3)The experiment of leguminous green manure planting(alfalfa)in the fourth year showed that the comprehensive quality score of fruit continued to rise with the delay of harvest time and reached the maximum on September 20th.At this time,the single fruit weight,transverse diameter,longitudinal diameter,fruit shape index,flesh moisture content and edible rate of fragrant pear all reached the peak,which were 189.07g,67.26mm,78.35mm,1.17,86.34%and 67.62%,respectively.In addition,it was found that there was a good linear relationship between the b~*value of pear seed color and its intrinsic quality index,which could provide a theoretical basis for fruit maturity evaluation.