The Effect of Low Temperature and High Temperature on Flowering and Pollination of Red Cartridge Kiwifruit in Western Guizhou in Early Spring of 2021

Based on the daily average temperature from March 19 to April 2,2021 at three surface meteorological stations in western Guizhou and the daily average temperature,maximum temperature and minimum temperature from March 19 to April 2,2021 at 12 main automatic meteorological stations of red cartridge kiwifruit base,the effects of low temperature and high temperature on flowering and pollination of red cartridge kiwifruit in early spring of 2021 were analyzed.The results showed that slight cold spell in later spring in western Guizhou occurred from March 21 to 23.The lower limit of the daily average temperature required for flowering period(12℃or below)appeared in each base of red cartridge kiwifruit during March 21-23,which affected the red cartridge kiwifruit trees in Faer,Houchang,Miluo,Shunchang,Panlong and Jichang bases flowering and pollinating before March 20.From March 29 to April 2,the daily maximum temperature of Faer and other eleven bases was 30℃or above,which caused the wilting and abscission of flowers and young fruits of of red cartridge kiwifruit trees in Faer,Houchang,Miluo,Shunchang,Panlong,shaomi,Jichang and Aga bases blooming and pollinating before March 24,but the flowers of red cartridge kiwifruit trees in Langdai,Longhe,Pugu and Shuangfeng bases blooming and pollinating after March 28 were not damaged.

Response of Different Varieties of Red Cartridge Kiwifruit to Temperature and Precipitation in Growth Stages

The responses of Hongyang,Donghong and Jinhong varieties to temperature and precipitation were analyzed by observing the growth stages of different kiwifruit varieties in Longhe red cartridge kiwifruit base of Liuzhi Special Zone of Guizhou Province in 2021 and combining with the meteorological data of temperature and precipitation in the base in the same period.The results showed that Hongyang,Donghong and Jinhong all sprouted on February 1,and had the same response to temperature and precipitation.From germination to leaf spreading stage,Hongyang and Donghong had the same response to precipitation,while Donghong and Jinhong had the same response to temperature,but Jinhong needed 32.5 mm precipitation to meet its growth and development.From leaf spreading stage to budding stage,Hongyang and Donghong had similar responses to temperature and precipitation,while Jinhong needed average daily temperature of 16.5℃and precipitation of 2.1 mm.The responses of the three varieties from budding to flowering to temperature and precipitation were consistent.From flowering to fruiting,Hongyang needed 19.9℃temperature and the least precipitation,while Jinhong needed the lowest temperature and the maximum precipitation.Donghong's response to temperature and precipitation was between Hongyang and Jinhong.During the period from fruit setting to fruit ripening and picking,Hongyang needed the least temperature and precipitation,while Donghong and Jinhong had the same response to temperature and precipitation.In the key period of fruit expansion of the three kiwifruit varieties in 2021,temperature and precipitation were the most suitable for fruit expansion.In short,red cartridge kiwifruit has a good response to temperature and precipitation in different growth stages,and it requires 201 d for Hongyang variety from germination to maturity and picking,211 d for Donghong variety and 218 d for Jinhong variety.