Biological Principle In High Yield And Technical System Of Extensive Cultivation Of Red Fuji Apple In Dryland

Consulting the vigorous cultivation model of Red Fuji in Japan,this study takes reasonable and effective control to the individual and groups in orchard according to the existing prominent problems in production of Red Fuji in dryland.On this basis,the dynamic and static multi-directional investigation of roots and shoots were carried out according to the biological characteristic difference in high-,mid-and low-yield orchards after reasonable control.By means of such investigation,we preliminarily explored the control points of key technology in extensive management of Red Fuji in dryland,and then put key technology into field experiment and investigated and studied from 2006 to 2008 in Luochuan county, Shaanxi Province,and finally,the technology regulation on extensive management of Red Fuji in dryland was worked out from conclusion and analysis.The main results were as follows:1.In accordance with the two peak periods of new shoots and fruits of red Fuji in dry region,and the absorption and transformation characteristics to fertilizer,fertilizer with Nitrogen-fertilizer being dominant should be carried out in late March.Because of the drought in early spring Weibei fruit growing area,the topdressing system should be done with irrigation one time to meet the demands of new shoots and fruit promote the rapid expansion of fruit and increase the year's yield.Topdressing with N and P being coordinated should be carried for second time in late May,which was not only for the shoots and fruit's needs for fertilizers and water but also for promoting the flower shoot differentiation.The third time for topdressing with K being dominant should be done in early July and August,to promote fruit expansion,being colored,and also increase fruit yield and quality.The flowers and fruits should be strictly and early thinned before 10^th June,so as to promote early cell division of fruits and increase the fruit shape index and fruit size.In late May to late June,the summer comprehensive management should be strengthened to promote flower shoot differentiation and increase its quality.2.The fertilization time and location of Red Fuji in dryland was further determined through the investigation on roots.The production formation in high-yield orchard had closely relation to the vertical and horizontal distribution density of roots.Roots in high-and mid-yield orchard concentrated at 20-40cm,where has the optimum mini-ecological condition which was a best system pattern.However,the concentrated level for low-yield was 0-20cm.The number of roots in high-yield orchard was around two times of that in mid-and low-yield orchard,meanwhile in various range of vertical and horizontal distribution the number of roots was much higher than that in mid- and low-yield orchard.The apple root system showed an economic growth pattern in which there were less big roots but more small one.The fresh weight in low-yield orchard was much greater than that of mid-yield one and the small root with strong absorptive capacity took the relative small proportion because of the bigger diameter.3.The trunk in high-yield orchard for Red Fuji in dryland should be controlled at about 1 meter,height 2.8 meter,total number of main branch less than 8,spreading angle 90 degrees; the number of long-,medium-,short-branch and total branches per mu was 178,413.4,894.8,1486.2 respectively;The ratio of branch to fruit was 2.57:1 and ratio of fruit to leaf 52.86:1;the fresh and dry weight of 100 leaves was 75.446 and 34.532g respectively;fruit spacing 25.7cm,leaf shape index 3.9 and the transmission rate of light was 33.325%.4.The soil available N in orchards with the application of organic manure increased by 9%than that applied with the single chemical fertilizers,available P decreased 8.3%, available K increased 22.2%.The organic matter per hm² increased 52.7%and production 4698kg,therefore the net income per hm was higher than 19189.5yuan.The growth of new shoots,thickness and weight of 100 leaves in orchard applied 45000kg biogas per hm²was significantly lower than that applied 75000kg sheep manure.However,reverse results was obtained when the orchard applied 75000kg and 1125000kg biogas.5.The highest soil nutrients in the vertical distribution of high-,medium-and low-yield orchard was 0-20cm layer,20-40cm followed by.The vegetation and farming system made 80-100cm layer the minimum.The soil nutrients amount in high-yield orchard was 2.27 and 1.23 times than that in medium-and low-yield one respectively.The high-yield orchard was applied large manure and small chemical fertilizers and meanwhile carried into green covering,which had function of improving soil organic content,modifying soil structure and promoting soil moisture and further enhancing soil fertility.These measurements improved the internal quality of fruits and ensured stabilizing yield.6.The moisture content in depth in Red Fuji orchard in dryland showed the curve-wave changes with different section,which took some certain rule of peaks and troughs.And the soil section corresponding to each trough would form the dry layer.The transportation of soil deep-layer water by fruit trees after years growth had changed the vertical position of water dry-layer.In the process of production,extensive water-saving cultivation measures should be taken and the principle of" to protect surface water,to fully utilize mid-level water and to excavate deep-level water" must be followed.7.Considering the occurrence rule of pests and diseases in Red Fuji orchard in dryland, precise control was carried and the obvious results was achieved in accordance with the requirements of organic fruits.The ratio of early needle-cast was lower that control after spraying 5 times biogas,moreover the vigorous growth of apple trees and darkened green leaf and light hazards of other pests and diseases were observed.Utilizing yellow cardboard to prevent yellow aphid in the period of migration according to its phototaxis had had obvious effect.8.Apple adopted on 20^th to 25^th Sept.were suitable for long-term storage.Fuji apple had completed its physiological maturity and been into the best fresh food period.Early-harvest had significant effect on the yield,taking 20^th Sept.and 15^th Oct.as comparison,weight of single fruit was less 53.8g,according to the amount 12000 of apple per 666.6m²,the difference in the yield was 645kg per 666.6 m².Supposed market price was 2.4yuan per kg, net income would be lower 1548yuan per 666.6m².