壶瓶枣不同发育期果皮显微结构与裂果的关系

调查结果显示,壶瓶枣裂果主要发生在半红期和全红期,半红期以前裂果率极低。随着果实的发育,枣果皮进入半红期和全红期,表皮和皮下层细胞出现典型的衰老、凋亡特征,表现为细胞变形、皱缩,横向变短、纵向增长,有色物质较多,壁加厚、轮廓不清;表皮细胞出现龟裂,为果皮水分渗透敞开了通道;皮下层厚度的变化直接影响着果皮厚度的变化。受皮下层细胞变形、皱缩的影响,果皮厚度在半红期和全红期变薄,导致果皮破裂应力降低,增加了裂果的风险。果皮结构及形态上的变化可能是造成枣裂果的重要原因。

Study on the Relationship between Histological Structure and Fruit Cracking during Development in Huping Jujube

Huping jujube was used as the material in the study. The fruit cracking of Huping jujube occurred mainly at the part-red stage and full-red stage, however, the cracking rate was very low before part-red stage. With the development of the Huping jujube, from part-red stage, some red substance appeared in the cells, and both cuticle cells and epidermal cells expressed as cell deformation,shrinkage, shorter lateral, vertical growth and cell wall thickening, all of these suggested that the cells became senescent and apoptotic.Epidermal cells appeared cracks for moisture penetration. Because of the deformation and shrinkage of cuticle cells and epidermal cells,the skin became thinner from part-red stage, which resulted in reduce of pericarp fracture stress and increased the risk of cracking. All these might be reasons of the fruit cracking.