Comparative micro-morphological and anatomical analysis of leaves of cultivated and hybrid forms of weedy sunflower

Abstract

There are various opinions in the literature about the importance of morpho-anatomical features of leaves, such as number of stomata, presence of trichomes, cuticle thickness, cell size, leaf thickness, etc. for susceptibility of plants to foliar herbicides. Since the differences in the plant's sensitivity to herbicides may be due to differences in leaaf sufrace and inner structure of leaves, in this research we pefrormed a detailed micromorphological and anatomical analysis of leaves of tolerant and sensitive sunflower forms, both cultivated hybrids and wild populations of hybrid forms (HFDS). It is interesting that there were no significant differences in the number of trichomes and stomata between resistant and susceptible HFKS populations, but in comercial sunflower genotypes it was. Namely, the number of stomata in the sensitive comercial sunflower hybrid were significantly higher than in the tolerant ones, but the tolerant hybrids had significantly more leaf hair than the sensitive one, so it is possible that the higher density of trichomes makes it impossible for the herbicides to reach the surface of the leaf epidermis, resulting in their less uptake. It has also been shown that plants with different susceptibilities to herbicides also differ in various anatomical parameters.