橘红肉甘薯块根类胡萝卜素的变化规律及其与主要经济性状的相关性

【目的】研究橘红肉甘薯块根鲜薯类胡萝卜素含量在生育过程中和品种间的变化规律及其与主要经济性状的相关性。【方法】试验于栽插后50、64、78、92、106、120和134 d调查15个橘红肉甘薯品种的最长蔓长，分枝数，结薯数，茎、叶、柄、块根干率，茎、叶、柄、块根鲜重，测定鲜薯类胡萝卜素含量，薯干淀粉、可溶性糖和粗蛋白含量，分析茎、叶、柄、块根干重，整株鲜重、干重，茎、叶、柄、块根干重占整株干重的百分比等数值，以及类胡萝卜素积累量与其余产量性状的变化和品质性状积累量日增长量的相关性。【结果】橘红肉甘薯块根类胡萝卜素含量在生长发育过程中出现总体平稳型、一直增加型和曲折上升型3种变化类型，对最长蔓长、块根鲜重、块根干重、光合产物的分配等经济性状的发育有不同的生物学响应。大多数橘红肉甘薯，尤其是一直增加型品种，其类胡萝卜素含量与最长蔓长、块根鲜重和干重、光合产物在块根的分配比例显著正相关，与光合产物在叶、柄的分配比例显著负相关，而与其它性状的相关性不高。类胡萝卜素日积累量增长量与块根鲜重、块根干重、淀粉、可溶性糖和粗蛋白积累量等日增长量呈正相关性，类胡萝卜素积累与块根膨大、干物质及营养物质积累存在协同关系。【结论】由于类胡萝卜素积累与干物质积累存在的协同关系在不同品种中的反应机制不同，类胡萝卜素含量在橘红肉品种间产生差异和分化，存在3种不同变化类型。

Variation Laws of Carotenoids Content in Storage Root of Orange-Fleshed Sweetpotato and Its Relationships with Major Economic Traits

【Objective】Accumulation laws of carotenoids content in storage root during development and among varieties and their relationships with major economic traits in orange-fleshed sweetpotato (Ipomoea Batatas (L.) Lam) were studied in present paper.【Method】The dynamics of main economic traits in 15 orange-fleshed sweetpotato varieties on 50, 64, 78, 92, 106, 120, and 134 d after transplanting were investigated, and these traits included the carotenoids content, longest vine length, branches number of vine system, storage roots number, dry matter contents in stem, foliage, petiole and storage roots, fresh and dry weights of storage roots, fresh and dry weights of stem, fresh and dry weights of foliage, fresh and dry weights of aboveground plant, fresh and dry weights of whole plant, and ratios of photosynthate to storage roots, stem, foliage and petiole. The relationship between variations of the carotenoids content and other economic traits during whole developing stage was analyzed. And the relationship between daily growth rates of the carotenoids accumulation and other main economic traits was also analyzed. 【Result】During the whole development, the carotenoids content had three variation types, that is totally leveling, straightly increasing and deviously ascending, and had different responses to the growth of longest vine length, fresh and dry weights of storage roots, photosynthate distributions, and so on. For most of the tested varieties, especially the straightly increasing type in the study, the carotenoids contents had a significant positive correlation with longest vine length, fresh and dry weights of storage roots and ratio of photosynthate to storage roots, and had a significant negative correlation with the ratio of photosynthate to foliage and petiole, however had a least correlation with other traits. Because of the positive correlation between daily growth rates of carotenoids accumulation and fresh and dry weights of storage roots, starch accumulation, soluble sugar accumulation, crude protein accumulation, the carotenoids and dry matter, main nutrient substances accumulated synergistically in storage roots. 【Conclusion】The significant difference and differentiation of carotenoids contents among varieties would take place during development of orange-fleshed sweetpotato, and there were totally leveling, straightly increasing and deviously ascending variation types of carotenoids content because of the synergistical accumulations between carotenoids and dry matter in storage roots among varieties. These variations of carotenoids accumulation had different relationships with main economic traits during development and among varieties in orange-fleshed sweetpotato.