Vol. 10, Issue 10 (2021)

Author(s):
Kokila Indira MA, Vanitha C, Sundareswaran S and S Marimuthu

Abstract:
Groundnut (Arachis hypogaea L.) is one of the most important oilseed crops. The semi-spreading and spreading kinds (Virginia types) have extensive dormancy periods, whereas the majority of Spanish and Valencia bunch cultivars lack seed dormancy. A study was undertaken in the Department of Seed Science and Technology, Tamil Nadu Agricultural University to determine the involvement of the testa, cotyledon and embryonic axis in the manifestation of seed dormancy in two different varieties of groundnut VRI 8 (Non-dormant) and CO 6 (Dormant). A germination test was conducted for the seeds with testa, without testa and embryonic axis by using freshly harvested seeds of variety VRI 8 and CO 6. The groundnut CO 6 dormant variety with testa recorded the lowest germination (17.6 %) and highest fresh ungerminated seeds (76 %) than non-dormant variety VRI 8 (71.2 % &18.4 %). The highest viable seed was recorded in CO 6 dormant variety (92 %) than VRI 8 (80%) and embryonic axis of both VRI 8 and CO 6 recorded 98.4 % germination. Total phenol content of CO 6 groundnut seed testa was much greater (116.81 µg/g) than non-dormant VRI 8 seed testa (41.8 µg/g). The dormant variety CO 6 contains more phenolic compounds in the seed coat than the cotyledon and embryonic axis.