【作者】 曾义安；

【导师】 朱月林；

【作者基本信息】 南京农业大学 ， 蔬菜学， 2004， 硕士

【摘要】 黄瓜（Cucumis Sativus L.）是世界各国人民喜食的重要蔬菜之一，但由于其根系弱、吸水吸肥能力差，对各种逆境抵抗力较差，导致黄瓜很难周年供应或产量较低。随着嫁接技术在黄瓜栽培上的应用和发展，这些问题部分得到了解决，尤其是在黄瓜越冬栽培上。然而，目前的嫁接理论研究尚存在不足，大多集中在嫁接的作用，而对嫁接优势的内在机制鲜有报道，探明内在机制可以为黄瓜嫁接技术更好地推广和应用提供可靠的理论依据。 本试验以黑籽南瓜为砧木，津绿21-1和津研4号为接穗形成的的嫁接黄瓜为研究对象，相应的自根黄瓜为对照，对嫁接黄瓜的光合特性、营养元素吸收、保护酶活性以及激素和蛋白质等生理指标进行了研究，探讨了嫁接优势的生理机制。结果表明：嫁接黄瓜在不同时期的形态指标均高于自根植株；嫁接黄瓜的单株产量显著高于自根黄瓜，单株产量在津研4号嫁接植株上表现的嫁接优势比津绿21-1更明显；枯萎病、病毒病、霜霉病和灰霉病四种病害在嫁接黄瓜上的病情指数和发病率均低于自根黄瓜；嫁接和自根黄瓜的净光合速率（P_n）和气孔导度（G_s）均是随叶片衰老而降低，胞间CO₂浓度（C_i）先降低，末期有所上升，但嫁接黄瓜的净光合速率（P_n）、气孔导度（G_s）和胞间CO₂浓度（C_i）在不同时期均极显著高于自根植株；净光合速率（P_n）在津研4号上表现的优势比在津绿21-1上更明显；嫁接黄瓜叶片中N、P、K、Ca、Mg含量均显著高于自根植株；嫁接和自根黄瓜叶片中可溶性蛋白含量随叶片衰老逐渐降低，但嫁接黄瓜中的含量始终高于自根黄瓜；嫁接和自根黄瓜叶片中SOD和CAT的活性随叶龄增大而呈下降趋势，POD活性先增强后降低，但嫁接黄瓜的SOD、CAT和POD活性始终高于自根黄瓜；MDA含量随叶龄的增大而增加，但是嫁接黄瓜中MDA的积累显著低于自根黄瓜；嫁接黄瓜叶片GA和ABA含量也与自根黄瓜存在显著差异，测定后期嫁接黄瓜ABA含量显著高于自根黄瓜，嫁接黄瓜叶片ABA／GA值在测定的各个时期均显著高于自根黄瓜；通过等电聚焦聚丙烯酰胺双向电泳（IEF-SDS PAGE）对叶片可溶性蛋白进行分析对比，发现在嫁接黄瓜叶片中产生了1～2种特异蛋白。更多还原

【Abstract】 Cucumber (Cucumis sativus L.) is one of the important vegetables that are enjoyed by worldwide people. For cucumber’s system of root, capacity of absorbing water and fertilizer and resistance to all kinds of stresses are poor, high yield and all-year-round supply of cucumber are very difficult to realize. With application and development of grafting technology for cucumber, the problems have been partly solved, especially, winter planting of cucumber. But grafting theories have many deficiencies, many studies were focused on function of grafting, and studies on physiological mechanism of grafting superiority were rarely reported. Making sense of the mechanism can provide convincing theoretical foundation for application and development of grafting technology of cucumber.Using black seed pumpkin {Cucurbita ficifolia Bouche) as root stock, and two cucumber cultivars JinlU21-1 and Jinyan 4 as scions, grafting was made to compare the differences in photosynthetic parameters, leaf nutrient element contents, activities of membrane protective enzymes and MDA contents, leaf GA and ABA contents, and leaf soluble protein components between grafted and self-root cucumber, and physiological mechanism of grafting superiority was discussed. The results showed that morphological indexes at different stages of grafted cucumber were significantly higher than those of self-root cucumber. The individual plant yield of grafted cucumber was significantly higher than that of self-root cucumber. Grafting superiority in individual plant yield of Jinyan 4 was better than that of Jinlu21-l. Disease index and disease percentage of wilt, virus, downy mildew and botrytis of grafted cucumber were lower than those of self-root cucumber. Accompanied with senescence of leaf, photosynthetic rate and stomatal conductance decreased gradually, at the same time, intercellular CO2 concentration decreased in first stage and rised in late stage, but photosynthetic rate, stomatal conductance and intercellular CO2 concentration of grafted cucumber were significantly higher than those of self-root cucumber at different stages. Grafting superiority in photosynthetic rate of Jinyan 4 was better than that of Jinlu21-1. Leaf N P K, Ca and Mg contents of grafted cucumber were significantly higher than those of self-root cucumber. With senescence of leaf, soluable protein contents in leaves of grafted and self-root cucumber decreasedgradually, but soluable protein contents in leaves of grafted cucumber were higher than those of self-root cucumber. With the increase of leaf age, SOD and CAT activities of grafted and self-root cucumber decreased gradually, at the same time, POD activities of grafted and self-root cucumber decreased in last stage as well. But SOD, CAT, and POD activities of grafted cucumber were significantly higher than those of self-root plant. MDA contents in leaves of grafted and self-root plant both rised, but MDA content of grafted cucumber was significantly lower than that of self-root plant. Leaf GA and ABA contents at various measuring stages of grafted cucumber were significantly different to those of self-root cucumber. ABA content at the last measuring stage of grafted cucumber was significantly higher than that of self-root cucumber. ABA/GA values of leaves of grafted cucumber were significantly higher than those of self-root cucumber at various measuring stages. Soluble proteins extracted from the leaves of grafted and self-root cucumber were analyzed using the technique of two-dimensional polyacrylamide gel electrophoresis. The results indicated that there were one to two additional protein spots from grafted cucumber.更多还原