Key Cultivation Techniques Of One Year Two Harvest System Without Overlap For Grape Under Protected Facilities

Summer Black grape in South China can increase the yield by two-harvest-a-year cultivation technique.This paper gave a detailed introduction about two-harvest-a-year cultivation techniques for grape that includes degreening and defoliation after first harvest,bud cutting,shoot setting,topping,reasonably thinning of flowers and fruits,bagging method,picking time,water and fertilizer management,disease and pest control etc.Of them,reasonable thinning of flowers and fruits is the key technique which can improve the quality of the grape.After the first harvesting about one month’s recovering for the grape tree can ensure the production and quality of the next harvesting.1.Degreening chemicals and spraying time affect significantly flower bud sprouting in summer.Spraying degreening chemicals from 21 days to 28days after harvest of summer crop has the highest rate of sprouting flower bud.The rates of spraying 400mg/L ethephon +0.4%sulfur was 195.45%,significantly higher than those of 400mg/L ethephon(107.15%)and 0.4%sulfur(110.40%).While the rate of spraying 400mg/L ethephon+0.4%sulfur 3 weeks after harvest was 144.75%,significantly higher than those of 400mg/L ethephon(97.35%)and 0.4%sulfur(86.75%).However,no difference was made between the spraying degreening chemicals 3 weeks and 4 weeks after summer harvest.2.Degreening chemicals should be sprayed between 2 and 3 weeks after summer harvest.Rate of sprouting flower bud degreening at 2 weeks after summer harvest in 2014 reached 207.77%,higher than that at 3 weeks with 193.56%,but there is no significant difference.Rate of sprouting flower bud degreening at 3 weeks after summer harvest in 2015 reached 204.16%,still higher than that at 2 weeks with 183.42%,but there is no significant difference.Sprouting flower bud could be obtained in the treatment of no spraying degreening chemicals.The rates were 161.25%in 2014,and 122.02%in 2015.3.Number of retained bud after pruning had a significantly effect on flower bud sprouting in summer.In 2015,retained winter buds with 5-8 resulted in percentage of sprouting flower buds with 144.0%、133.58%、136.63%and 146.60%,respectively,and had significantly better effect than that with 2-4 buds.While summer buds with 6-10 sproutedlower buds with the percentage of 167.15%、195.23%、201.57%、211.43%、237.5%,respectively,and had significantly better effect than that with 2-4 buds.4.Bud breaking chemicals significantly led to sprouting flower bud in summer.2.5%cyanamide+2.0%Baoguoliang+0.02%Shenzhonggen had highest sprouting rate of flower bud in both winter and summer season crops.The rate of summer crop were 139.3%in 2013,156%in 2014 and 177.3%in 2015.respectively,significantly higher than that of 2.5%cyanamide,2.0%Baoguoliang,0.02%Shenzhonggen individually,and combination of both.While the rate of winter crop were 127.6%in 2013,179.2%in 2014 and 190.5%in 2015.The rate of both summer and winter crop induced by Bud breaking chemicals has no significant difference5.Cluster and fruit weights of winter crop were 377g and 5.8g,significantly lower than those of summer crop with 518 and 7.4g respectively.However,contents of total soluble sugar and titrate acid were 23.4%and 8.9%higher than those of summer crop,showing no significant difference.Anthocyanin content in peel of winter fruit was 7.51mg/g,significantly higher than that in summer with 6.23mg/g.6.Fruit maturation of summer crop ripen from June 1 to July 30,and the one from winter crop from Dec.1 to Jan.30 in the following year.The total yield of two crop of 2-age,3-age,4-age and 5-age of ’Summer Black’grape was 1370.2kg×15/ha,1670.7kg×15/ha,1925kg×15/ha,2045kg×15/ha,respectively.The yield ratio of winter crop to summer crop should keep from 2:5 to 3:5,and the total annual yield in 2000kg×15/ha of 5-age of grape to ensure the sustainable production of two harvest without overlap for Summer Black grape.