Effects of different pollination methods on expansion of bitter gourd

ObjectiveThe effects of different pollination methods on expansion of bitter gourd were studied to pro-vide reference for the protected cultivation of bitter gourd.MethodGuinong 6 bitter gourd was used as experimental ma-terial.The bitter gourd were continuously pollinated for 5 d in green house by artificial pollination(bagging treatment)and bee pollination respectively.The fruit setting rate was counted everyday;horizontal diameter,vertical diameter,circum-ference and weight of single fruit were measured 1,4,7,10 and 14 d after pollination,and daily average relative growth rate was calculated.The content of soluble solids and vitamin C in bitter gourd were tested during fruit mature period.Re-sultThe horizontal diameter and circumference of bitter gourd through artificial pollination were bigger than those of bi-tter gourd through bee pollination during the whole growth period.On day 14 after pollination,the vertical diameter of bi-tter gourd through bee pollination were bigger than that of bitter gourd through artificial pollination.The relative growth rate of horizontal diameter,vertical diameter and circumference in the two pollination methods both decreased.The rela-tive growth rate of horizontal diameter and circumference of bitter gourd through artificial pollination was significantly higher than those of bitter gourd through bee pollination(P<0.05,the same below)1-4 d after pollination.The single fruit weight of bitter gourd through bee pollination increased obviously in the late stage of growth.The relative growth rate of single fruit weight decreased rapidly 5-7 d after pollination while the relative growth rate of bitter gourd single fruit weight through artificial pollination was significantly higher than that of bitter gourd through bee pollination.Then the relative growth rate of single fruit weight increased slightly on day 10 after pollination.Fruit setting rate of bitter gourd through bee pollination was lower than that of bitter gourd through artificial pollination.However,fruit index,contents of soluble solids and vitamin C in fruit through bee pollination was higher than those in fruit through artificial pollination.Conclu-sionBitter gourd through artificial pollination grows rapidly in the early and middle stage of growth.Bitter gourd through bee pollination grows rapidly in the late stage of growth and bee pollination can improve fruit quality of bitter gourd.