Study On The Effect Of Big Apple Seedlings Orchard Establishment In The Weibei Arid Region Of Shaanxi Province

As a high-quality production area of apple in China,the drought area in the weibei arid region of shaanxi province has a long history of apple cultivation.With the continuous development of the apple industry,the tree ages of the old orchard will increase year by year,leading to the gradual aging of the tree body,which reduces the yield and fruit quality of the tree.It is urgent to renovate and improvement the old orchards.So the selection of seedlings suitable for seedling age is the reliable guarantee for realizing rapid orchard construction and early fruit and high-yield.This experiment was divided into two parts: experimental research and investigation.In the experimental research section,2a,3a and 4a apple seedlings were used for orchard establishment,and different degree of pruning were adopted after seedling planting.Study on the growth of saplings after the establishment of large seedlings was conducted.In the investigation section,an investigation of 4 orchards was conducted using 3a seedlings.After planting,the survival rate,growth condition,yield and fruit quality of large seedlings were studied,and comprehensive analysis.It has chosen the appropriate seedling age and the degree of pruning after planting.The main results are as follows:(1)With the increase of pruning degree,the leaf area,the leaf area,chlorophyll and net photosynthetic rate of 3 kinds of seedling young trees gradually increased.2a-HP(2 years heavy pruning: dry height of 80 cm),3a-HP(3 years heavy pruning:50 cm of elongated shoot of main branch was cut off,remove the competing branches of elongated shoot and a strong branch),4a-HP(4 yearheavy pruning:remove 5 shoots)leaf area,chlorophyll content,net photosynthetic rate were the maximum of 2a,3a and 4a seedling,respectively.The leaf quality and net photosynthetic rate of 2a-HP and 3a-HP were not significant,but were significantly higher than that of other treatments.The leaves of 2a-HP and 3a-HP grew well and the photosynthetic capacity was enhanced,which was conducive to tree growth.(2)The proportions of the short branches of 3a and 4a seedlings were about 55.67% and 68.33% respectively.which was beneficial to early fruit and high yield.With the increase of pruning degree,the number of new shoots,total branches and net plant height growth of 3a and 4a increased gradually,the number of new shoots,total branches and net plant height growth of 3a-HP were 32.77%,2.02% and 6.34% higher than that of 3a-LP(3 years light pruning:50 cm of elongated shoot of main branch was cut off,remove the competing branches of elongated shoot),the number of new shoots,total branches and net plant height growth of 4a-HP were 6.74%?17.53%?14.71% higher than that of 4a-LP(4 yearlight pruning:remove 3 shoots).The 3a-HP and 4a-HP trees grow robustly with more branches,which is beneficial to tree culture.(3)In the second year of the construction of the 3a soil ball seedlings,fruiting was started.The yield was 2.24 kg/plant and 186.12 kg/667m2.It was at least one year earlier than the 2a conventional seedlings,the fifth year after the establishment of the garden,The yield per mu of 3a seedlings with soil ball is 30.78% higher than that of 2a conventional seedlings.so the 3a soil ball seedling establishment can indeed achieve achieve early fruits and early high yields.(4)Comprehensive all tree indexes,and the 4a seedlings were transplanted with more labor and difficulty.The following conclusions were drawn:The 3a-HP comprehensive performance was the best.The 3a seedlings were used to build the garden and the heavy pruning method was used to build the garden.(5)The survival rate of soil seedlings at the Luochuan Experimental Station(Northwest Agriculture and Forestry University Luochuan Apple Experimental Station))was 98.81%,which was about three times that of the First Village(the first village of Luochuan Apple)and Beiyi(Zizhou Beiyi Agricultural Development Co.,Ltd).The number of new shoots in Luochuan Experimental Station was 21.93% and 24.48% higher than that in the First Village and Beiyi respectively,and the plant heights were 7.63% and 9.24% higher respectively.Improving the survival rate and growth potential of large seedlings with soil ball seedlings.The survival rate of polished rod seedlings in Guxian Village(Guoxian Village,Jiuxian Township,Luochuan County)was 2.4 times that of branched seedlings.Therefore,there are risks in constructing large seedlings.It is best to use large seedlings with soil ball or large seedlings for nutrition when constructing a garden,root damage can be reduced as much as possible.No seedlings with earthballs are required.The root system of seedlings must be viable,and And the root number of healthy lateral roots is more than 5,fibrous roots are dense.If the seedling root coefficient is small,the branches of large seedlings will be removed and the lightening rods will increase the survival rate.