Floral biology of kerstings groundnut (Kerstingiella geocarpa Harms\}

Floral biological studies of three varieties of kerstings groundnut (Kerstingiella geocarpa Harms) were conducted at the glasshouse of University of Nigeria, Nsukka, during 1988 and 1989. Two seeds of each variety were sown in 28 cm polythene pots fertilized at 0.371, 0.474 and 0.142 grams of urea, single superphosphate and muriate of potash respectively per pot. The experiment was laid out as a completely randomized design with four replications. NSK 2 variety was classified as early whereas NSK 1 and "Ex- Mali" were classified as late varieties with respect to days to flower bud emergence, first flower, 100 per cent flowering and flowering duration. The duration from flower bud emergence to anthesis were 5.5, 6 and 6.5 days in NSK 2, Ex-Mali and NSK 1 respectively. The late varieties produced higher seed yield compared to the early variety, but the differences were not significant. There was a positive and significant correlation (r=0.999) between duration from flower bud emergence to anthesis and seed yield indicating that seed yield can be adequately predicted when this duration is known. Flowering duration varied from 22 days in the early variety to 31 and 33 days in the late varieties with peak period of anthesis occurring in both varieties between 12 h'and 14 h. Anthesis in the morning was late (benyeen 6.10 a.m. and 7.15 a.m.) in the early variety and early (between 5.30 a.m. and 6.00 a.m.) in the late varieties. Flowers closed in all varieties between 5.30 p.m. and 9.30 p.m. Dehiscence of anthers started 7-8 h before anthesis. Longevity of viable pollen grains was more when preserved at lower temperature and relative humidity than under room temperature and relative humidity. Pollen fertility was high in all the varieties. The stigma became receptive to viable pollen in the three varieties from 12 h before anthesis and up to 6 h after.