Study On The Chemical Thinning Of Fruits And The Suitable Yield In The Apple Orchard Of Arid Area

This experiment selected metamitron,lime sulfur,calcium-formic acid,olive oil,carbaryl,6-benzyladenine,naphthalene acetic acid,sodium naphthalene acetic acid eight kinds of thinning agents to treat the ‘Fuji'.Through the comparison of the flower thinning rate,empty fruit rate and the single fruit set rate,a comprehensive comparison of fruit quality and yield was supplemented.It is to find the best thinning agent and application method for Luochuan county.And through the study of the suitable load of apple in Luochuan county,the aim is to find out the suitable load index of‘Fuji'apple in Luochuan county during the fruit period,so as to provide basis for the later sparse degree of chemical thinning.The following results are achieved:1.The best chemical thinning flowering agents were 0.5 g/L and 1 g/L metamitron.Observing from the flower thinning rate,empty fruit rate and single fruit set rate,0.5 g/L metamitron was respectively 75.9%,33.0%,62.5%.And 1 g/L metamitron was respectively74.9%,40.0%,45.8%.They were close to the artificial sparse that was 89.8%?50.5%?100%mostly.Lime sulfur was the second.2.The best chemical thinning fruit agent was 500mg/L carbaryl,The flower thinning rate,empty fruit rate,single fruit set rate were respectively 66.4%?13.8%?66.8%.It was close to the artificial sparse mostly.Sodium naphthalene acetic acid was the second.3.The fruit quality of Fuji apple was not affected by the other agents except 500 mg/L carbaryl which caused the fruit rust of young Fuji apple.4.Carbaryl,Lime sulfur,0.5 g/L Metamitron can increase the yield of ‘Fuji'.And other chemical thinning agent significantly effected on the yield of ‘Fuji'.5.From the comprehensive consideration of the effects,economic benefits,and practical ease of use,it is considered that 0.5 g/L Metamitron is most suitable for practical use.6.It is suggested that the 20-year-old Fuji's suitable load in the medium-level orchard in Luochuan county can be controlled at 2500~3000 kg/mu.It can guarantee high quality,high yield and efficient,stable production.