【作者】 贾晓梅；

【导师】 温陟良；

【作者基本信息】 河北农业大学 ， 果树学， 2004， 硕士

【摘要】 冬枣是目前公认的品质最好的鲜食枣品种。虽然冬枣已有上百年的栽培历史，但由于对其研究较晚，栽培技术尚未完善，在生产过程中存在许多问题，其中最突出的问题之一就是冬枣的坐果率低。本试验初步探索了冬枣落果的生理机理，并且为了有效提高冬枣的坐果率，改善其果实品质，进行了不同环剥宽度对冬枣果实发育期可溶性总糖及其组分、可滴定酸、维生素C、可溶性蛋白等物质含量变化规律影响的研究。主要研究结果如下： 1 不同树势对冬枣的落果程度有影响，强树的总落果量＞弱树＞中等树。冬枣的落果主要有两个高峰，前期高峰是在7月下旬，落果速度快，量大，势强；后期高峰是在9月下旬，落果慢，量少，占冬枣整个发育期总落果量的比例低。 2 冬枣胚的发育主要集中在硬核期以前，树势对冬枣种子的败育影响不大，种子败育是冬枣的一种遗传特性。 3 冬枣种子的败育是引起落果产生的原因之一，此外，枣果内的低含量的GA、IAA、ZR和高含量的ABA是导致其落果的原因，同时枣果内高含量的氮素、低含量的钙素和可溶性糖、蛋白质也与落果的产生有关。 4 不同环剥宽度对试验树果实的生长趋势没有明显影响，冬枣果实纵横径、鲜重及体积增长均为不典型双“S”曲线。 5 不同环剥宽度的试验树果实中可溶性总糖含量不同，环剥宽度1.2cm的含量最高，0.6cm的最低，变化呈相同的趋势，即果实内的可溶性总糖含量是在生长后期迅速积累达到最高，而在果实发育前期变化并不明显。果实内可溶性总糖各组分中，蔗糖在生长前期含量很低，在8月上旬开始剧增，最终成为枣果内主要的糖类物质。 6 不同环剥宽度的试验树枣果中可滴定酸含量变化趋势基本相同：幼果含量高，成熟果含量低。 7 树体进行不同环剥宽度处理后，试验树枣果中Vc含量变化总体上均是低→高→低的趋势，8月中旬含量最高。 8 可溶性蛋白在不同环剥宽度的试验树枣果中含量的变化趋势相同，7月初和9月中旬分别是蛋白含量的高峰期。 9 不同环剥宽度的处理对树体影响不同，环剥宽度为0.9cm的试验树坐果率最高，环剥宽度1.2cm的试验树枣果在含糖量和可溶性蛋白含量方面显著高于其它处理和对照，故从环剥宽度对试验树果实的品质和产量影响的主要方面考虑，对于树势中庸的4年生冬枣树在生产上建议采取盛花期0.9cm～1.2cm的环剥宽度。更多还原

【Abstract】 Ziziphus jujuba cv. Dongzao has been widely taken as the best jujuba fresh-fruit cultivar at present. Dongzao was a superior cultivar which has a cultivation history of more than one hundred years, but the research of it just was began recently, planting techniques were not so perfect, and there were many technical questions in its production, such as the lower natural setting percentage. In this experiment, the physiological mechanism of Dongzao fruit drop was studied. And for increasing natural setting percentage availably and improving fruit quality, the variation of soluble sugar, titratable acid, vitamin C and soluble protein were also observed during fruit development with girdling Dongzao tree. The main results were as follows:1 Different tree vigor affected the degree of dropping fruits. The number of dropping fruits was strong tree > feeble tree > middle tree. There were two peaks of dropping fruit during the fruit development, the first one took place in the last ten-day of July; the second one in the last ten-day of September. The degree was severer in the former period than in the later.2 Most Dongzao embryo grew before stone hardening stage. Seed abortion was one of heredity character, and it was no relation with tree vigor.3 The phenomenon of dropping fruit occurred for seed abortion, IAA> GA^ ZR of low content and ABA of high content. There were also many reasons in the dropping fruits, such as N of the high content, and Ca, soluble sugar and protein of the low content, etc.4 Different girdling widths did not affect the growth tendency of Dongzao fruit. The growth curves of fresh weight, volume, diameter and length showed double "s" shape, but they were not modeled.5 The soluble sugar contents in different girdling width Dongzao tree had the same trend, i.e., in the early stage of fruit development, the changes of the contents of soluble sugar were not obvious; during fruit maturation the contents of soluble sugar accumulated rapidly. Before maturation the content of sucrose was little, but the content was run up with fruit developing, and it became the important soluble sugar at maturation. The highest content of soluble sugar was the fruit of tree with girdling 1.2cm, and the lowest was one with girdling 0.6cm.6 The contents of titratable acid in different girdling width Dongzao tree had the same trend. The contents were the highest in the early stage of fruit development. And they decreased with the development of fruits.7 The contents of vitamin C in different girdling width Dongzao tree showed low→high→low in the course of fruit development and kept a high level in the middle ten-day of August.8 The contents of soluble protein in different girdling width Dongzao tree had the same trend. The highest level was in the first ten-day of July and the middle ten-day of September.9 The different girdling width affected growth of tree. The natural setting percentage of girdling width 0.9cm was highest in the trees with girdling. The contents of soluble sugar and soluble protein were highest in the fruit of tree with girdling 1.2cm. And considering the quality and yield, girdling width between 0.9cm and 1.2cm was suit to 4 years Dongzao tree in full bloom.更多还原