Rajesh Kumar Jain
SIRDA Group of Institutions, Sundernagar, H.P INDIA
E-mail: duggarjain@yahoo.co.in
Abstract: The first flower was opened on an average 29th day and the single continuous flowering period was 26-30 days . The average number of pollen grains per anther 369.8 and per chamber 92.44 have recorded . The variation in the number of pollen grains among flowers in this variety may be caused by the variation in male phase duration. The results suggest that variation in male and female function among flowers within inflorescences may affect the fitness of a plant through differential male and female reproductive success in this species . The ovules number per ovary and per plant were 18.2 and 930.8 respectively . The total number of pollen grains on stigma were 37.3 while the germinated pollen number on stigma was 9.7. The average number of fertilized ovules were 10.8 and the maximum number of seeds per fruit were 10.3. The stigmas were receptive upto 4 days after anthesis . Intravarietal crosses were 75% successful and seed setting was 65 % . The high positive correlation has been found between germinated pollen grains and fertilized ovules per ovary(+0.8189) .
Keywords: Brassica niger, Pollen grains , Sex allocation ,Correlation
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