甜荞野生近缘种观察与利用研究

Wild Relatives of Common Buckwheat:Observation and Utilization

为了较大幅度提高栽培甜荞的产量水平,利用甜荞野生近缘种优良资源改良传统的甜荞选育高产品种。经观察统计,野生近缘种荞麦与甜荞外部形态完全相同,仅花器构造不同。其中野生近缘种荞麦茎秆坚硬,生育期适中,具有雌雄蕊等长、自交可育(结实率高达41.9%~62.6%,套袋自交结实率为21.2%,),且与甜荞杂交也可育等优点。但是,也存在着落粒性较强和易穗发芽等缺点。栽培甜荞雌雄蕊异长(异花授粉),结实率仅有12.9%,套袋自交结实率仅0.9%(表明自交不育)。野生近缘种荞麦作母本,甜荞作父本的F_(1)代呈现出父本红色羽翅的遗传标记,证明确系杂交种。产量结果调查发现,母本平均单株产量6.3 g,千粒重20.4 g;F_(1)平均单株产量23.4 g,千粒重27.1 g,F_(1)产量是母本3.7倍,杂种优势十分显著。实验Ⅱ结果显示,F_(1)呈现父母本花冠色泽的中间颜色,为不完全显性,植株较矮,花器构造为雌雄蕊等长。F_(2)代分离出5株花冠颜色与父本完全相同的深红色植株,其中2株花器构造与母本相同(雌雄蕊等长),结实率为47%;3株与父本完全相同(雌雄蕊不等长),结实率小于10%。实验表明野生近缘种荞麦与普通荞麦具有亲和性,杂种优势强,而且自交可育、结实率高,是十分珍贵的种质资源,有望改变普通荞麦的低产状况。

To increase the yield of cultivated common buckwheat,the traditional common buckwheat varieties with high yield were improved by using the superior related wild resources of buckwheat.According to the observation and statistics,the external morphology of wild relatives and cultivated common buckwheat were identical,while the floral structures were different.Among them,the stems of wild relatives were hard and the growth period was moderate,and wild relatives of buckwheat also had the advantages of equal length of pistils and stamens,self-fertility(the seed setting rate was as high as 41.9%-62.6%,and the bagging self-crossing seed setting rate was 21.2%)and fertility after hybridizing with common buckwheat.However,there were also some disadvantages in the wild relatives,such as strong seed shattering and easy panicle germination.The common buckwheat had extremely long stamens(cross-pollination)and the setting rate of crossing and bagging self-crossing(indicating self-crossing sterility)were only 12.9%and 0.9%,respectively.F_(1)(wild relatives used as the female parent and common buckwheat as the male parent)showed the genetic markers of male parent’s red wings,which indicated that it was a hybrid definitely.The yield results showed that the average yield per plant of female parent was 6.3 gram and the thousand-grain weight was 20.4 g,while the average yield of F_(1) was 23.4 g per plant and the thousand-grain weight was 27.1 g.The yield of F_(1) was 3.7 times that of the female parent plant,showing significant heterosis in F_(1).The results of experimentⅡshowed that F_(1) had the middle color of parental corolla,which was incomplete dominant.Besides,the plant height was relatively low and its pistils and stamens in floral structure were with equal length.In F_(2) generation,five dark red plants,the same color of corolla as their male parent,were isolated;among which,2 plants had the same flower structure as their female parent(the equal length of pistils and stamens).The seed setting rate of these five plants was 47%.Another three plants were heterogony,which was the same as their male parent,and the seed setting rate was less than 10%.The study indicates that the wild relatives of buckwheat have cross compatibility with common buckwheat,and they possess strong heterosis,self-fertility and high seed setting rate,so they could be considered to be a quite precious germplasm resource to improve the low-yield situation of common buckwheat.