Study On Chemical Flower-thinning And Fruit-thinning Techniques Of Red Fuji Apple And Suitable Load At Full Fruit Stage

Red Fuji is the main apple variety in China,accounting for about 70% of the total apple area in China.However,the age phenomenon of Red Fuji apples is serious,which has a great influence on the growth,yield,quality and benefit of trees.Controlling the appropriate load by thinning flowers and fruits can not only keep the tree growing healthily,but also improve the fruit quality and benefit.Chemical flower thinning and fruit thinning can greatly reduce labor costs,but at present,due to the lack of standardized technical standards for chemical flower thinning and fruit thinning period,chemicals and application concentration,the popularization and application of chemical flower thinning and fruit thinning technology are limited.This experiment mainly studied the rational use period,concentration and effect of different flower and fruit thinning agents,and discussed the relationship between load and fruit quality and benefit by controlling load.The main research results are as follows:1.Chemical flower thinning agents were sprayed twice at the early flowering stage(75%-85% of the central flower blooms)and the full flowering stage(100% of the central flower blooms)of’ Nagan Fuji No.2 ’ apple.Compared with the control of spraying clear water twice,spraying chemical flower thinning agents had significant thinning effect.Among them,spraying 0.5 g/L benzodiazepine(F1)resulted in 36.22% empty table,24.64%flower fruit setting and 63.78% inflorescence fruit setting.Spraying 30 g/L olive oil(F2)has an empty table rate of 24.43%,a flower setting rate of 39.54% and an inflorescence setting rate of 75.57%.Spraying 100 times zhi shu you hua(F3),the empty table rate,flower fruit setting rate and inflorescence fruit setting rate were 31.69%,32.54% and 68.31%,respectively.Spraying 10 g/L calcium formate(F4)resulted in an empty table rate of 38.73%,a flower setting rate of 25.00% and an inflorescence setting rate of 61.27%.Spraying 200 times of 25 Baume-du lime sulfur mixture(F5),the empty table rate,flower fruit setting rate and inflorescence fruit setting rate were 32.06%,28.78% and 67.94%,respectively.The contrast,empty table rate,flower fruit setting rate and inflorescence fruit setting rate of the control were only 7.77%,48.77% and 92.23%,respectively.According to the comparison,0.5 g/L benzodiazepine(F1)and 10 g/L calcium formate(F4)have the best flower thinning effect,followed by 100 times zhi shu you hua(F3)and 200 times 25 baume lime sulfur mixture(F5),and 30 g/L olive oil(F2)has the worse flower thinning effect.2.In the young fruit stage of’ Nagano Fuji No.2’,the fruit thinning agent was continuously sprayed twice with the central fruit diameter of 0.6-0.8cm and 1.0-1.2cm,and it was found that the empty table rate was 35.55% and the single fruit ratio was 46.60% after spraying 2.5 g/L zhi shu you guo(F6).Spraying 2.0 g/L zhi shu you guo(F7)has an empty table rate of 28.09% and a single fruit ratio of 42.62%.Spraying 0.02 g/L naphthylacetic acid(F8)resulted in 32.13% empty table and 45.05% single fruit.The empty table rate of control was only 7.77%,and the proportion of single fruit was only 23.50%.Compared with the control,all three fruit thinning agents have significant thinning effect,among which 2.5g/L zhi shu you guo(F6)has the best thinning effect.3.Different treatments of chemical flower and fruit thinning agents had no adverse effects on the internal and external quality of’ Nagano Fuji No.2’ fruit,and the single fruit weight and yield were increased by spraying chemical flower and fruit thinning agents on the premise of consistent fruit retention.4.In the 7-year-old’Nagano Fuji No.2 ’/M26/ Malus octophylla orchard with 1.5 m×4m plant spacing,the effects of different loads on tree growth,yield and quality were studied.It was found that with the increase of load,the length and thickness of new shoots decreased,the leaf area decreased,the contents of N,P and K in leaves,branches and fruits decreased,and the soluble solids in branches and the proportion of large fruits decreased By comparison,it was found that 110 fruits/plant(yield 2619.30kg/ mu)were left in the early stage of full fruit production,and the trees were robust in growth,high in nutrient utilization rate,good in fruit quality,and the maximum in profit value.5.In the orchard of’ Nagano Fuji No.2’/M26/ Malus octophylla with a row spacing of 6m×8 m and a tree age of 25 years,it was found that with the increase of load,the values of leaf parameters decreased,fruit type index decreased,soluble solids decreased,titratable acid value increased,fruit quality decreased,the proportion of small fruits increased and the income value decreased.According to the comparative analysis,full fruit period has a load of400/plant(1683.21kg/ mu),with large leaf parameters,good fruit quality,large proportion of excellent fruits and the largest income.