ABSTRACT:
Withania somnifera L. the 3" important medicinal plant among 32 prioritized medicinal plants listed by the NMPB. Its rot is the economic part which is repository of number of secondary metabolites known as withanolides having many therapeutic actions, including antitumor, immunoregulatory, anti-inflammatory, toning up the uterus, antibiotic, curing skin disease, bronchitis, and ulcer to name a few. Therefore, for developing genetically superior varieties its reproductive biology was studied and its knowledge used for genetic improvement of crop. With reference to the study of its reproductive biology, stigma receptivity was in peak at 0.6 and 0.7 cm length from stigma to ovary. The stigma of open flower showed negligible receptivity, pollen shape is spherical and pear shaped with 90- 100 um width and 100 to 110 um length and stained dark red big in size with acetocarmine stain, which coincided with the stage of peak stigma receptivity. The pollen of open flower was mostly triangular in shape. Thus it is self pollinated, chasmogamous, in nature, anthesis time was between 7:30 am to 11:00 am, therefore crosses were attempted during the peak period of stigma receptivity, for this the available 9 genotypes of Ashwagandha were crossed to check the cross ability. It was found that the crop was self and cross compatible. Of the 22 hybrids evaluated, 11 reciprocal cross expressed by the cross combination JA-20 and JA-134, for MWS-314/IGAU-1, RAS-16/1GAU-I, JA-20/MWS-134, WS-90-141/JA-20, and RAS-16/JA-20, had the lowest difference. All the direct and reciprocal hybrids showed significant and positive standard heterosis over JA-20, JA-134, The magnitude of hcterosis ranged from 74.5% to 56% with JA-134 and 42 to 66.9% for fresh root yield. For dry root yield, it ranged from 59% to 72.0% with JA-20 and 75% to 801% with JA-134. Since there were differences in performance between crosses it could be interpreted that the cytoplasmic influence differs with nuclear background and it is actually the result of interaction between cytoplasmic and nuclear genes. Therefore, the influence of the cytoplasm on agronomic attribute exhibiting difference cytoplasm effects and proper selection of parents to be used as female or male can lead to better heterotic combination for higher production and productivity per unit area to generate more income for livelihood.