Abstract:In order to understand the secretion rule and components of litchi (Litchi chinensis) nectar, the nectar secretion pattern of male and female flowers in ‘Nuomici’ (‘NMC’), ‘Guiwei’ (‘GW’) and ‘Huaizhi’ (‘HZ’) were studied in cloudy and sunny days. The results showed that there was no significant difference in air temperature between sunny and cloudy days, but the relative air humidity of cloudy day was significantly higher than that of sunny day. The nectar amount in cloudy day was more than that in sunny day, and female flowers secreted nectar more than male flowers, as well as ‘NMC’ and ‘GW’ more than ‘HZ’. The soluble solid content in nectar at sunny day was higher than that in cloudy day, in especial of female flowers. The soluble solid content in nectar was the highest in ‘HZ’, reached up to 37.7%, followed by ‘GW’, and ‘NMC’ was the lowest for 17.7%. The soluble sugars were mainly composed of glucose, fructose and sucrose by HPLC, and the content of glucose was the highest. The soluble sugar content of in ‘HZ’ nectar of female flowers in sunny day was 450.36 μg mL-1, which was significantly more than that of other two cultivars. These would provide scientific basis for cultivation and nectar production of litchi.