کد مقاله | کد نشریه | سال انتشار | مقاله انگلیسی | نسخه تمام متن |
---|---|---|---|---|
2179845 | 1095086 | 2012 | 7 صفحه PDF | دانلود رایگان |
![عکس صفحه اول مقاله: Floral morphology and breeding system in Polygonum hastato-sagittatum Mak. (Polygonaceae) Floral morphology and breeding system in Polygonum hastato-sagittatum Mak. (Polygonaceae)](/preview/png/2179845.png)
Distyly has been clearly confirmed in Polygonum hastato-sagittatum Mak, which is dimorphic for the intrinsic features of style height, anther height and a suite of ancillary pollen and stigma polymorphisms. The stigma width of long styled flowers is larger than that of short ones, and L-morph (long) stigmas have longer and less number of papillae than the S-morphs (short). Flowers produced significantly smaller pollen grains, but in greater numbers, in L-morph than in S-morph. In P. hastato-sagittatum, style-morph ratios were associated with population size: larger populations always exhibited 1:1 morph ratios, or were slightly L-biased, whereas smaller populations were often strongly L-biased, and only occasionally S-biased. Populations containing only the L-morph were occasionally found, but populations fixed for the S-morph were not observed. The biased style-morph ratios maybe result from morph-specific differences in assortative mating or artificial disturbance. The study supports the theory that evolution of heterostyly reduces the conflict that can occur in sexually monomorphic animal-pollinated species, achieving efficient cross-pollination but simultaneously avoiding self-interference between female and male sexual organs.
Journal: Flora - Morphology, Distribution, Functional Ecology of Plants - Volume 207, Issue 5, May 2012, Pages 365–371