Studies On The Basic Biology Of Storability Of Longan Fruit Among Cultivars

Longan (Dimocarpus longan Lour.) is a famous subtropical fruit species in the South of China. Since longan fruit mature during the hot and humid August/September in China, the fruit deteriorate rapidly after harvest due to percarp browing, aril breakdown and decay, the fruit have a very short postharvest life of 3~4 days at ambient temperature. This short postharvest period limits its long-distance transportation, marketing and consumption. Therefore, the basic biological research of storability becomes a key problem in the development of longan production. In this experiment the pericarp morphology and structure of longan (Dimocarpus longan Lour.) fruit among ten varieties, being the chief cultivars in Fujian Province, were investigated.And then we chosed different kinds of storability of longan fruits (Dimocarpus longan Lour. cv. Fuyan) and (Dimocarpus longan Lour. cv. Dongbi) as meterials, researched the defference of storability and browing in pericarp and aril breakdown when the different kinds of longan fruits are keet in storage. The results were as follows:1. The pericarp morphology and structure of longan (Dimocarpus longan Lour.) fruit among ten varieties, being the chief cultivars in Fujian Province, were investigated. The results indicated that there were apparent differences on pericarp thickness, exocarp surface color, moires, radial lines, tumor shape projecting and setas, exocarp lenticels, periderm layer thickness, suberin layer thickness and continuity, mesocarp parenchyma cell arrangement, stone cell size, content, arrangement and distribution, the developed state, arrangement and distribution of vascular bundle, the arrangement of epidermis cells and the thickness of cuticle and wax layer in the endocarp, depending on various cultivars. Fruits of cvs. Fengliwei, Dongbi, Youtanben, Wulongling, Honghezi and Jiaoyan,had thick pericarp, many tumor shape projecting and setas in the exocarp surface, thick periderm layer, thick suberin layer with good continuity in the exocarp, many stone-cell(groups) with closer arrangement which distributed in mesocarp surface and had large proportion when stone-cell(groups) thickness compared to mesocarp...