黄绿色苹果品种果锈发生表皮形态学观察初探

Morphological Observation on Epidermis of Fruit Rust in Yellow-green Apple Cultivar

【目的】我国苹果品种中部分黄绿色品种表现出锈多、锈重、果实外观质量较差等缺点,影响了果实的商品价值,本试验旨在为黄绿色苹果果锈与表皮的关系研究提供理论支撑。【方法】试验以‘维纳斯黄金’‘烟香玉’‘赛金’‘明月’等6个黄绿色品种为试材,对其表皮进行侧切,利用显微镜观察有锈部位和无锈部位的差异。【结果】将6个品种发生果锈和未发生果锈部位进行对比,结果显示各个品种未发生果锈的部位角质膜质地均匀,果实外观较好。而发生果锈的品种各有不同:‘瑞雪’果皮外表光滑,光洁度比较高;‘维纳斯黄金’果锈大量发生部位角质膜出现裂缝,且蜡质层脱落严重;‘华金’发生果锈的部位少量蜡质层脱落,果面光洁度不高;‘烟香玉’发生果锈后蜡质层脱落,木栓化角质层依然排列紧密且相对平整,果实光洁度尚可;‘明月’果锈部位表皮细胞排列不规则、松散且间隙多,果实光洁度也表现一般;‘赛金’发生果锈皮下细胞依然排列紧密、整齐,果面光洁度表现良好。【结论】果面光洁度与角质膜的均匀一致性关系非常密切。无果锈的果实表皮有较完整的角质层、表皮和皮下组织,当果锈发生时,角质膜有不同程度损伤,随着果锈发生严重程度的不断加深,表皮蜡质层和角质层脱落,表皮细胞出现木栓化组织代替了原来的表皮层,形成果锈。

【Objective】Some yellow-green apple cultivars in China showed many shortcomings,such as more rust,heavy rust and poor fruit appearance quality,which affected the commodity value of fruit.The purpose of this experiment was to provide theoretical support for the relationship between yellow-green apple fruit rust and epidermis.【Methods】Six yellow-green cultivars of‘Venus Gold''Yanxiangyu’‘Saijin’and‘Mingyue’were used as test materials.The epidermis was cut laterally and the difference between rusty and non-rusty parts was observed by microscope.【Results】The parts with and without fruit rust of 6 cultivars were compared.The results showed that the texture of cuticle in the parts without fruit rust was uniform and the appearance of fruit was good.The cultivar of fruit rust is different:‘Ruixue’peel smooth appearance,high finish;the cuticle of‘Venus Gold’fruit rust occurred a large number of cracks,and the wax layer fell off seriously;‘Huajin’fruit rust parts of a small amount of wax layer off,fruit surface finish is not high;the wax layer of‘Yanxiangyu’fell off after fruit rust,the cork cuticle was still arranged closely and relatively flat,and the fruit was smooth.‘Mingyue’fruit rust part of the epidermal cells arranged irregularly,loosely and more gaps,fruit finish is also general;‘Saijin’fruit rust subcutaneous cells are still closely arranged,neat,fruit surface finish good.【Conclusion】The fruit surface smoothness was closely related to the uniformity of cuticle.The epidermis of the fruit without fruit rust have a relatively complete cuticle,epidermis and subcutaneous tissue.When fruit rust occurs,the cuticle had different degrees of damage.With the deepening of the severity of fruit rust,the cuticle wax layer and cuticle fall off,and the epidermal cells appear.The cork tissue replace the original epidermis and form fruit rust.