The implications of aberrant anatomical and histochemical features in the anthers of male sterile dsf-15 sunflower - Helianthus petiolaris Nutt.

Abstract

Present investigation aims at determining the developmental stage at which the male sterile anthers of DSF-15 Helianthus petiolaris Nutt. deviate from their isogenic fertile counterparts and the underlying histochemical factors responsible for that deviation. The flower buds of fertile and male sterile H.petiolaris were fixed in the Carnoy’s fluid, dehydrated in ethyl alcohol series, embedded in paraffin and microtomed. The sections were stained for the localization of insoluble polysaccharides, RNA and total proteins using periodic acid Schiff’s toluidine blue and mercuric bromophenol blue reagents respectively. The results of the present investigation reveal that, during premeiotic stages, anthers of fertile and sterile lines are indistinguishable except in the occurrence of starch storage in the sterile anthers during the onset of meiosis. In the sterile anthers, precocious degeneration of callose failure of microscope wall information, persistent abnormal tapetum (hypertrophied or premature plasmodial formation), failure of formation of endothecial thickenings accompany the abortion process of microspores. The malfunctioning of the tapetum seems to be responsible for male sterility in DSF-15 H.petiolaris.