荔枝花蜜分泌规律及可溶性糖组分和含量的分析

Analysis of Secretion Pattern and Soluble Sugar Composition and Contents in Litchi Nectar

摘要:

为了解荔枝（Litchi chinensis）花蜜的分泌规律和主要组分，对‘糯米糍’、‘桂味’和‘怀枝’3个主栽品种雄花和雌花的花蜜分泌模式进行研究，并测定花蜜中可溶性糖的组分和含量。结果表明，采样期间果园阴天和晴天气温差异不明显，但阴天的相对空气湿度显著高于晴天。总体上阴天的荔枝花蜜分泌量高于晴天，雌花的花蜜分泌量高于雄花，‘桂味’和‘糯米糍’的花蜜分泌量均高于‘怀枝’。晴天花蜜中的可溶性固形物含量高于阴天的，且在雌花中表现尤为明显。‘怀枝’花蜜中的可溶性固形物含量最高，可达37.7%，‘桂味’其次，‘糯米糍’最少（17.7%）。利用高效液相色谱检测，荔枝花蜜中主要可溶性糖组分为葡萄糖、果糖和蔗糖，以葡萄糖含量最高。晴天时‘怀枝’雌花花蜜中可溶性糖含量达450.36 μg mL^-1，显著高于另外两个品种。这为荔枝栽培和花蜜生产提供科学依据。

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.