Research On The Main Cultivation Technologies Of Low-yield Mango Orchard Reconstruction In Baise,Guangxi

Baise city is China’s main mango producing area.Mango is one of the important cash crops in Baise city.However,due to poor management and other reasons,there are still some low-yield orchards(<300kg/667m~2),which seriously restrict the development of the mango industry.Based on the investigation and analysis of the causes of low-yield mango orchards in the main producing area in Baise,Guangxi,this paper carried out the main cultivation technology researchon the transformation of low-yield mango orchards such as top-grafting,application of organic fertilizers,scientific spraying plant growth regulators,and sod-culture in mango orchard.The research achievements may provide theoretical basis and experimental data for the transformation and innovation of mango low-yield orchard in Baise,Guangxi.The main research results are as follows:1.The effects of different grafting varieties,grafting height,scion type and scion length on the survival rate and scion growth after top-grafting were studied.The results were showed as followed:The survival rate of top-grafting varieties on‘Jinhuang mango’as the intermediate stock was‘Jinxing mango’>‘Guire mango No82’>‘Tianyang xiangmang’>‘Prainda mango’>‘Xinshiji mango’,and the survival rate was the highest at 2 m grafting height;the scions from different batches of mature shoots pruned after harvest last year had little effect on the growth of grafted varieties;the scion length should be between 10 cm-15 cm.2.The effects of four kinds of organic fertilizers on the yield and fruit quality of 4-year-old Guire mango No.82 and their soil properties were analyzed.The results were indicated as followed:(1)Reasonable application of organic fertilizer can increase the yield and fruit quality of mango.The effect of 20 kg or 30 kg organic fertilizer B and 20 kg or 30kg organic fertilizer D on the yield of mango is obvious.The fruit quality was better to apply organic fertilizer D 30 kg/tree,organic fertilizer A 20kg or 30 kg/tree and organic fertilizer B 30 kg/tree.There were significantly different from the control in their content of soluble solids,the ratio of sugar and acid,and the content of vitamin C.(2)The organic fertilizer can improve the physical and chemical properties of mango orchard soil.The more organic fertilizer applied,the higher the soil organic matter content.The four kinds of organic fertilizer applied could improve four enzyme activities such as soil catalase,sucrase,urease and acid phosphatase,Moreover,higher organic matter content in fertilizer used,the higher the related soil enzyme activities.The application of organic fertilizer D 20kg/tree or 30 kg/tree could significantly increase soil nutrients.3.The 8-year old mango‘Tainong No.1’treees were used as test materials.3 treatments such as plant growth regulator+reasonable fruit thinning(referred to as"phytoregulator"),phytoregulator+foliar fertilizer+reasonable fruit thinning,phytoregulator+foliar fertilizer+no thinning were studied while spraying water+reasonable fruit thinning was used as control.Compared with the control,the three treatments could significantly improve the fruit weight and yield of mango,and it is best in the treatment with phytoregulator+foliar fertilizer+reasonable fruit thinning among the three treatments.the treatment with phytoregulator+foliar fertilizer+reasonable fruit thinning could delay the decrease of fruit firmness,and the peel color parameters are better than other treatments.However,the content of soluble solids and the ratio of sugar to acid in the fruit of the three treatments were lower than those in the control group,some index of fruit quality were not ideal and needed further study.4.The five treatments such as white clover,purple vetch,dwarf lentils,natural grass and clear cultivation in mango orchard were designed to understand the influence of sod-culture on the cultivated environment and fruit quality of mango.The results indicated as followed:(1)White flower clover and natural grass treatment can naturally overwinter which did not need to sow next year,while dwarf lentils and purple vetch needed to be sowed next year.(2)The grasses which was the highest in per 667 m~2 a year in the indicators such as total nitrogen content,the total phosphorus content,the total potassium content,the total calcium content and the total magnesium content were purple vetch,short lentil,natural grass,short lentil and dwarf lentils repectively.(3)Cutting backfill once in that year could improve the physical and chemical properties of the soil,Except for the white clover,the orchard grass can increase the organic matter content of the soil.The the organic matter content of the soil with the purple vetch was highest and reached14.33g/kg,The soil cation exchange capacity at a depth of 30 cm after cutting and backfilling was increased in all grass treatments;The raw grass will reduce the content of alkaline nitrogen in the soil and the content of alkaline nitrogen in the soil with white clover reduced the most.Moreover,white clover could significantly increase soil available potassium and available phosphorus content.The exchangeable calcium content and exchangeable magnesium content were the highest in natural grass treatment.The sod-culture could increase the total number of microorganisms in soil,but there were not obvious differences compared with control.The catalase activity in the soil with white clover was the highest.,soil urease activity and soil phosphatase activity was related to soil nitrogen and phosphorus content.White clover and lentil planted in the orchard reduced significantly soil invertase activity.(4)The sod-culture could improve soluble solid contents,Vc and acid-sugar ratio in mango fruit,and mango fruit quality planted with purple vetch was better than other treatments.