白及果实形态与种子结实率相关性研究

Correlation between fruit form and seed setting rate of Bletilla striata

关键词:  白及, 果实形态, 结实率, 种子, 种胚

Key words:   Bletilla striata, fruit form, seed setting rate, seed, seed embryo

摘要:

该研究以果实大小有明显差异的26个白及果序共87枚果实为材料,分析了果实形态(包括果实重量、长度及直径)与种子结实率的相关性。结果表明:果实重量与结实率的相关性最为密切,相关系数为0.786,达到中等正相关; 其次是果实直径,相关系数为0.634; 最后是果实长度,相关系数为0.553。对10枚果实及种胚大小测量结果显示,果实形态与种胚大小相关性为弱相关,不同果实种胚大小相差较大,种胚直径和种胚长度平均分别为177.9 μm和359.0 μm,最大分别为241.9 μm和528.6 μm,最小分别为64.5 μm和114.3 μm; 单粒白及种子平均重3.90 μg,87枚果实中,单枚果实平均种子数量为10 436粒,最大为39 488粒。该研究结果表明果实重量及饱满程度(直径),可以作为评价白及果实质量(种子结实率)的参考指标。

Abstract:

Bletilla striata is a perennial herb belonging to the family Orchidaceae, has been used as Chinese folk medicine. Seed quality is key to get large number of B. striata seedlings, and the seed setting rate is a very important standard to evaluate the fruit quality. It is a quick method to rough evaluate seed setting rate through the fruit form. In this study, the correlation between fruit form(fruit weight, length and diameter)and seed setting rates among 26 infructescences(87 fruits)of B. striatawere analysed, the seed embryo sizes of ten different sizes of B. striata fruits were measured, and the weights of 400 seeds were calculated and the weights of single seed were obtained. The results showed that correlation between fruit weight and seed setting rate were the most close, the coefficient of correlation was 0.786, reaching to moderate degree; the second close was fruit diameter, the coefficient of correlation was 0.634; and the last was fruit length, the coefficient of correlation was 0.553; the average setting rate of 87 fruits was 50.43%. The correlation between fruit form and seed embryo size was at a low degree, developmental state of seed embryo could not be known through the fruit form; the average diameter of embryo was 177.9 μm, the biggest was 241.9 μm, the smallest was just 64.5 μm; and the average length of embryo was 359.0 μm, the biggest was 528.6 μm, the smallest was just 114.3 μm, the results showed that the mature seed embryo size of B. striata mainly focus on 150-200 μm in diameter, the ratio was 62.34% in this range, and 300-400 μm in length, the ratio was 68% in this range. The average weight of single seed was 3.90 μg, the seeds in the biggest fruit of the 87 was 39 488, and the average number was 10 436, according to calculation, the average number of have embryo seeds in a single fruit was 5 263, it could gain a large number of B. striata seedlings through the sterile culture. In conclusion, fruit weight and full degrees(diameter)can be used to evaluate fruit quality(seed setting rate)of B. striata.