Technical Study On Promoting Flower Bud Formation And Fruit Setting And Quality Of Korla Fragrant Pear

In the 53 rd Regiment of the Third Division,taking 3-4-year-old Korla Fragrant Pear(Fragrant Pear for short)as the research object,the study was carried out to promote the formation of main flower buds of Korla Fragrant Pear and to improve fruit setting and quality by using growth regulators and liquid pollination.The experimental results are as follows:(1)The main trunk shape of Korla Fragrant Pear(Pyrus pyrifolia L.)in May-June branching and picking treatment promoted shooting,increased the number of middle and short branches and decreased the proportion of long branches;at the same time,promoted the formation of crown and axillary flowers,increased by 252.17% and 414.28% compared with the control,and increased the rate of flowering per plant by 43%.From May to June,the top and axillary flowers increased 116.41% and 261.11% and the flowering rate per plant increased 27% compared with July to August.The results showed that flower bud formation was promoted in May-June treatment,and the effect was better when combined with picking treatment.(2)PBO,gibberellic acid and gibberellic acid + boron treatment could increase the length of main branch and promote the growth of annual branch,while PP333 had inhibitory effect.High concentration of gibberellic acid and boron treatment promoted the growth of main branches,increased the growth of annual branches,and reduced the amount of branches more effectively than low concentration treatment.(3)For 3-year-old fragrant pear leaves,PBO treatment increased leaf area,10 mg/L gibberellic acid +boron treatment decreased specific leaf weight,chlorophyll content increased,SPAD value reached 38.90,followed by PBO.For 4-year-old fragrant pear leaves,PBO and 100 mg/L gibberellic acid treatment significantly increased leaf area,decreased specific leaf weight and increased chlorophyll content compared with the control.Gibberellic acid + boron and PP333 treatment compared with the control,leaf shape index decreased,leaf length,leaf width,leaf area increased significantly,specific leaf weight increased,chlorophyll content increased significantly.(4)For 3-year-old fragrant pear,gibberellic acid and PP333 treatment increased fruit setting rate.Highconcentration of gibberellic acid treatment was beneficial to fruit setting of top flower,low concentration treatment was beneficial to fruit setting of axillary flower,and the effect of PP333 was better for promoting fruit setting of axillary flower.For 4-year-old fragrant pear,PBO,gibberellic acid and PP333 treatment increased fruit setting rate,and the fruit setting effect of top flower was better than that of axillary flower,among which 80 mg/L gibberellic acid + boron treatment was the best.(5)PBO,PP333 and 10mg/L gibberellic acid + boron had better effect on fruit calyx removal,with the fruit calyx removal rates reaching 55.72%,55.35% and 55.34%,respectively.PBO treatment had the best effect on calyx removal of lower fruits,and 10mg/L gibberellic acid + boron and PP333 treatment could effectively improve the calyx removal rate of middle and upper fruits.(6)Plant growth regulators have obvious effects on the quality of fragrant pear fruit,and different treatments have different effects.The single fruit weight,fruit longitudinal diameter and fruit transverse diameter of fragrant pear treated with PBO were the largest,and the fruit point diameter was the smallest;the fruit point density of fragrant pear treated with 10mg/L gibberellic acid and boron was the smallest,the content of soluble solids,fruit Vc and fruit soluble sugar was the highest;the fruit point diameter and titratable acid content of fragrant pear treated with 80mg/L gibberellic acid and boron were the lowest;the peeling firmness of fragrant pear treated with 100mg/L gibberellic acid Minimum.(7)Liquid pollination had a significant effect on the growth of fragrant pear.Sugar + urea + boron,sugar + urea + boron + pollen 1.2g/L,sugar + calcium nitrate + PBO + agar + boron + pollen 0.8g/L treatment can promote shoot growth.The treatment of granulated sugar+calcium nitrate+PBO+agar+boron+pollen 0.8g/L promoted branch growth most obviously,the leaf specific leaf weight increased,and the chlorophyll content increased.(8)Liquid pollination could improve the fruit setting rate of fragrant pear.3-year-old fragrant pear had the best fruit setting effect on top bud with sugar+calcium nitrate+PBO+agar+boron+pollen 0.8g/L treatment,and the highest fruit setting rate on axillary flower with sugar+urea+boron+pollen 1.2g/L treatment.The fruit setting rate of 4-year-old fragrant pear was increased by 12.2% and 11.83% compared with the control,8.76% and 8.22% in inflorescence,8.52% and 5.1% in axillary flower,14.35% and21.17% in apical flower,respectively,when treated with granulated sugar + urea + boron + pollen 1.2 g/Land granulated sugar + calcium nitrate + PBO + agar + boron + pollen 0.8 g/L.(9)The calyx removal rate of fragrant pear fruit treated with granulated sugar+calcium nitrate+PBO+agar+boron+pollen 0.8g/L was the highest,and the best effect was 74.81%.The single fruit weight of fragrant pear treated with sugar,urea,boron and pollen 1.2g/L was the heaviest,and the titratable acid content decreased.The longitudinal and transverse diameters of fragrant pear fruits treated with granulated sugar + calcium nitrate + PBO + agar + boron + pollen 0.8g/L increased,the density and diameter of fruit points decreased,and the peeling hardness of fruit reached the minimum.At the same time,sugar + calcium nitrate + PBO + agar + boron + pollen 0.8g/L treatment increased soluble solids content,VC content,soluble sugar content,and reached the maximum.