不同倍性黄瓜植物学特征及生理生化的研究

发布时间：2018-05-11 13:00

本文选题：黄瓜 + 多倍体　；参考：《山东农业大学》2017年硕士论文

【摘要】：黄瓜具有重要的经济价值,是人们喜爱的蔬菜之一。其栽培历史悠久,近年来,随着黄瓜栽培面积的增加,人们对黄瓜品种质量的要求提高,迫切需要新的黄瓜种质资源,而植物多倍体可产生新的变异。多倍体植株具有生长健壮、抗逆性增强、果实增大以及营养物质含量高等特点,因此可用它来改良作物品质和抗逆性,从而提高作物产量。本研究以普通黄瓜二倍体(2n=2x=14)、同源三倍体(2n=3x=21)及四倍体(2n=4x=28)为材料,对其进行形态学、解剖结构、光合特性和抗逆等方面的观察研究,来探明多倍体黄瓜生理生化方面的基本特征,通过对其研究寻找黄瓜育种的新材料。本研究成果既可丰富黄瓜种质资源,也可以为选育高产高抗优质的黄瓜品种提供材料。主要研究结果如下:1、不同倍性黄瓜外部形态学差异较大。与二倍体黄瓜比较,四倍体黄瓜子叶和真叶厚而肥大、色深,植株的茎和叶柄增粗,叶片、花瓣、种子增大,单果重增加;而三倍体植株的真叶变大,茎和叶柄增粗,叶片、雄花花瓣增大,种子增大,子房和单果重无显著变化。2、不同倍性黄瓜茎叶解剖结构差异较大。随黄瓜倍性的增加,叶片厚度、上表皮厚度、下表皮厚度、栅栏组织、海绵组织、栅海比和叶柄的表皮厚度、皮层厚度、维管束面积、导管数目以及茎的表皮厚度、皮层厚度、维管束面积有增加的趋势。3、不同倍性黄瓜光合特性不同。以单位叶面积计算的叶绿素含量随倍性增加而增加,叶绿素a、叶绿素b、类胡萝卜素和总叶绿素的含量均是四倍体最高、三倍体次之、二倍体最低。不同倍性黄瓜的净光合速率日变化曲线表现为双峰型,都存在光合“午休”现象,峰值出现在10:00和13:00左右,第二峰值小于第一峰值。三倍体光合能力最强,而四倍体光合能力最低。4、四倍体花粉的可染率和萌发率仅为68.8%和43.6%,而二倍体的可染率和萌发率为94.4%和80.6%,二倍体大于四倍体,差异性极显著。5、三倍体和四倍体黄瓜果实维生素C、可溶性糖、可溶性蛋白、氨基酸等含量均高于二倍体,表明多倍体黄瓜营养物质含量高于二倍体。6、二倍体自交座果率和单瓜种子数均比四倍体高。在四倍体为父本、二倍体为母本的杂交组合中,杂交座果率和单瓜种子数比较高,反之则杂交座果率和单瓜种子数比较低。7、三倍体F_1黄瓜早期产量和总产量比二倍体F_1黄瓜分别增加了33.70%和22.69%,差异性极显著。商品性状三倍体F_1比二倍体F_1好,因此可知,三倍体F_1比二倍体F_1更适合用于生产。8、不同倍性黄瓜抗性不同,四倍体黄瓜植株抗白粉病和霜霉病能力比三倍体强,三倍体又比二倍体强。四倍体和三倍体的耐低温能力比二倍体强。
[Abstract]:Cucumber has important economic value and is one of the favorite vegetables. It has a long cultivation history. In recent years, with the increase of cucumber cultivation area, the quality of cucumber varieties is required to be improved, and new cucumber germplasm resources are urgently needed, and the plant polyploid can produce new variation. Polyploid plants have the characteristics of strong growth, enhanced resistance to stress, increased fruit size and high nutrient content, so it can be used to improve crop quality and stress resistance, thereby increasing crop yield. In this study, the basic physiological and biochemical characteristics of polyploid cucumber were studied by observing its morphology, anatomical structure, photosynthetic characteristics and stress resistance. A new material for cucumber breeding was studied. The results can not only enrich cucumber germplasm resources, but also provide materials for breeding cucumber varieties with high yield, high resistance and good quality. The main results were as follows: 1. Different ploidy cucumber had different external morphology. Compared with diploid cucumber, tetraploid cucumber cotyledons and true leaves were thicker and thicker in color, stem and petiole thickened, leaves, petals and seeds enlarged, and fruit weight increased, while triploid plants had larger true leaves, larger stems and petioles, and larger leaves. The male flower petals increased, the seeds increased, the ovary and single fruit weight did not change significantly. The anatomical structure of different ploidy cucumber stems and leaves differed greatly. With the increase of cucumber ploidy, leaf thickness, upper epidermis thickness, lower epidermis thickness, palisade tissue, sponge tissue, grid sea ratio and petiole epidermis thickness, cortical thickness, vascular bundle area, vessel number, stem epidermis thickness, cortical thickness, The area of vascular bundle increased. 3. The photosynthetic characteristics of different ploidy cucumber were different. The chlorophyll content per unit leaf area increased with the increase of ploidy. The contents of chlorophyll a, chlorophyll b, carotenoid and total chlorophyll were the highest in tetraploid, followed by triploid and lowest in diploid. The diurnal variation curve of net photosynthetic rate of different ploidy cucumber showed double peak type, and all had the phenomenon of "midday depression" of photosynthesis. The peak appeared at 10:00 and 13:00, and the second peak value was less than the first peak value. The photosynthetic ability of triploid was the highest, while the photosynthetic ability of tetraploid was the lowest. The staining rate and germination rate of tetraploid pollen were only 68.8% and 43.6%, while those of diploid were 94.4% and 80.6.The diploid was larger than tetraploid. The contents of vitamin C, soluble sugar, soluble protein and amino acid in triploid and tetraploid cucumber fruit were higher than those in diploid cucumber. The results showed that the nutrient content of polyploid cucumber was higher than that of diploid. In the hybrid combinations with tetraploid as male parent and diploid as female parent, the fruit setting rate and seed number of single melon were higher than that of tetraploid. On the contrary, the fruit setting rate and seed number of single melon were lower. The early yield and total yield of triploid F1 cucumber increased 33.70% and 22.69% than that of diploid F-1 cucumber, respectively, and the difference was very significant. Triploid F1 is better than diploid F1. Therefore, triploid F1 is more suitable than diploid F1 for production of .8. different ploidy cucumber has different resistance to powdery mildew and downy mildew, and tetraploid cucumber has stronger resistance to powdery mildew and downy mildew than triploid. Triploid is stronger than diploid. The low temperature tolerance of tetraploid and triploid was stronger than that of diploid.
【学位授予单位】：山东农业大学
【学位级别】：硕士
【学位授予年份】：2017
【分类号】：S642.2

【参考文献】