Study on the Variation of Greenhouse Temperature and Fruit Quality Difference of Summer Black Grape with Two-Harvests-a-Year in Southern Xinjiang

【Objective】 To study the temperature variation of Summer black Grape during the first and second ripening periods in Solar Greenhouse in southern Xinjiang,and analyze the difference of fruit yield and quality between the two crops. 【Results】 The results showed that the indoor temperature of ‘Summer black’Grape during the whole growth period was higher than that of the first ripening,and the daily mean temperature of the second ripening was above 10 ℃. The daily variation trend of indoor temperature of the first ripening was similar to that of the second ripening,and the temperature of the first ripening was larger than that of the first ripening before the rapid fruit expansion period,while that of the second ripening was higher than that of the second ripening The diurnal variation range of temperature in the greenhouse was larger after the expansion stage,and the difference of temperature difference between day and night was the most obvious during the flowering stage and fruit color changing stage. In the flowering stage,the average temperature difference between day and night of the first ripening was 58.1% higher than that of the second ripening. During the fruit color changing period,the average temperature difference between day and night of the second harvest was 46.3% higher than that of the first harvest; The single grain weight,single ear weight and yield per mu of the first ripening fruit were higher than those of the second ripening,but the commercial fruit rate was 5% lower than that of the second ripening. 【Conclusion】 Through the analysis and comparison of the indoor temperature of the first and second ripening,there are great differences in the daily average temperature change and the diurnal temperature difference in greenhouse,but the daily temperature change of the indoor temperature in each growth period presents a “single peak” trend. Combined with the temperature demand of grape growth and development,the suitability of greenhouse temperature for fruit growth and quality formation in the second ripening was better than that in the first ripening,and the commercial fruit rate was high. But affected by other factors such as tree nutrition,light and so on,the yield of the first ripe fruit is better.