6种豆科植物种子形态结构研究

Study on the morphological structure of seeds from six species of leguminous plants

为了研究广布野豌豆(Vicia cracca L.)、箭豌豆(Vicia sativa L.)、白花草木樨(Melilotus albus L.)、黄花草木樨(Melilotus officinalis L.)、高山豆(Tibetia himalaica Baker)、紫花苜蓿(Medicago sativa L.)6种豆科植物种子的形态特性,通过萌发实验、电镜扫描种皮、制作种皮石蜡切片及解剖并观察种子内部结构。结果表明:广布野豌豆种子硬实率为98.0%,发芽率为96.5%,发芽势出现在第6天(为40.5%),霉变率为1.0%,种皮较粗糙,栅栏层排列紧密,骨状细胞层厚;箭豌豆种子硬实率为8.0%,发芽率为83.5%,发芽势出现在第4天(为44.5%),霉变率为15.0%,种皮粗糙,栅栏层排列紧密,无骨状细胞层;白花草木樨种子硬实率为89.0%,发芽率为91.5%,发芽势出现在第2天(为54.5%),霉变率为3.0%,种皮粗糙,栅栏层排列紧密,无骨状细胞层;黄花草木樨种子硬实率为90.0%,发芽率为89.0%,发芽势出现在第2天(为58.0%),霉变率为3.0%,种皮粗糙,栅栏层排列紧密,无骨状细胞层;高山豆种子硬实率为88.0%,发芽率为93.5%,发芽势出现在第3天(为53.5%),霉变率为3.0%,种皮粗糙,栅栏层排列紧密且宽,有骨状细胞层;紫花苜蓿种子硬实率为7.0%,发芽率为89.0%,发芽势出现在第3天(为52.5%),霉变率为1.0%,种皮光滑,栅栏层排列疏松且短,无骨状细胞层。说明野生豆科植物的种子硬实率较栽培种高;打破休眠后,小粒种子较大粒种子更易发芽且发芽势出现较早;栅栏层和骨状细胞层可能是形成硬实现象的主要原因;种皮粗糙且表面沟壑较深的种子较种皮光滑的种子在发芽过程中更易发生霉变。

This paper's research objects are Vicia cracca L.,Vicia sativa L.,Melilotus albus L.,Melilotus officinalis L.,Tibetia himalaica Baker and Medicago sativa L.. In order To study the morphological characteristics of seeds from 6 kinds of leguminous plant,including Vicia cracca L.,Vicia sativa L.,Melilotus albus L.,Melilotus officinalis L.,Tibetia himalaica Baker and Medicago sativa L.,the germination experiment was carried out in the test. Furthermore,an electron microscope was used to scan the seedcoat,the paraffin section of seedcoat was made,and the internal structure of seeds was observed through dissecting the seeds. The result showed that the hard rate and germination rate of Vicia cracca L. seed were 98. 0% and 96. 5%,respectively; its germination potential appeared on the 6th day,which was 40. 5%; its mildew rate was 1. 0% and the seedcoat was rough,and the palisade layer was arranged closely and the osteosclereid layer was thick. The hard rate and germination rate of Vicia sativa L. seed were 8. 0% and 83. 5%,respectively; its germination potential appeared on the 4th day,which was 44. 5%; its mildew rate was 15. 0% and the seedcoat was rough,and the palisade layer was arranged closely without the osteosclereid layer. The hard rate and germination rate of Melilotus albus L. seed were 89. 0% and 91. 5%,respectively; its germination potential appeared on the 2nd day,which was 54. 5%; its mildew rate was 3. 0% and the seedcoat was rough,and the palisade layer is arranged closely without the osteosclereid layer. The hard rate and germination rate of Melilotus officinalis L. seed were 90. 0% and 89. 0%,respectively; its germination potential appeared on the 2nd day,which was 58. 0%; its mildew rate was 3. 0% and the seedcoat was rough,and the palisade layer was arranged closely without the osteosclereid layer. The hard rate and germination rate of Tibetia himalaica Baker seed were 88. 0% and 93. 5%,respectively; its germination potential appeared on the 3rd day,which was 53. 5%; its mildew rate was 3. 0% and the seedcoat was rough,and the palisade layer was arranged closely with the osteosclereid layer. The hard rate and germination rate of Medicago sativa L. seed were 7. 0%and 89. 0%,respectively; its germination potential appeared on the 3rd day,which was 52. 5%; its mildew rate was 1. 0% and the seedcoat was smooth,and the palisade layer was short and arranged loosely without the osteosclereid layer. The result indicate that the hard rates of wild leguminous plants are higher than those of cultivated ones,and the smaller seeds are easier to germinate and the germination potential appears earlier than the bigger seeds after breaking dormancy; the palisade layer and the osteosclereid layer may be the main reason for the formation of the hard seed; the seeds with rough seedcoat and a deep gully on the surface is easier to mildew than the ones with smooth seedcoat during the germination process.