Search

Brinjal hybrid seed production primarily utilizes the seed-to-seed method. Optimal results require synchronized stigma receptivity and pollen viability, timing of emasculation and pollination along with the appropriate quantity of pollen on the female parent's stigma. With this perspective, the research was carried out, employing the parents of the GJBH 4 brinjal hybrid. The study involved 18 experiments, considering two emasculation options namely emasculation on same day as flower opening, emasculation on a day prior to flower opening, three pollination times namely 8-9 am, 9-10 am and 10-11 am and three cross-pollination ratios namely two female flowers per male flower, four female flowers per male flower, six female flowers per male flower. The results revealed that for better hybrid seed yield, emasculation on the day prior to flower opening, pollination between 9-10 am and using one male flower to pollinate four female flowers could be adopted. [ABSTRACT FROM AUTHOR]

Pollen pistil interaction studies were carried out in six sunnhemp genotypes. Pollen viability percentage of the six genotypes ranged from 0.0 to 93.5% and pollen germination ranged from 0.0 to 84.0% at four different floral stages starting from bud to opening of a flower. The viable pollen grains were present at the later three stages of flower for globose type anthers, while the pollen grains were viable at the later two floral stages for heart shaped anthers. Stigma receptivity was high to very high during S3 and S4 stages. Artificial self-pollination and sib pollination with a mixture of pollen grains were carried out and in vivo pollen tube growth in the style was investigated using fluorescence microscopy. In self-pollinated pistils, eight hours after pollination, callose wall development was seen around the nucellus cell. However, under sib pollinated pistil, eight hours after pollination, pollen tube penetrated into embryo sac of an ovule. The formation of callose in self-fertilized pistil prevented fertilization and seed set. But sib pollinated flowers were fertilized normally and a seed set could be observed. The investigation proved the existence of selfincompatibility. [ABSTRACT FROM AUTHOR]

The present study aimed at evaluating the genetic variability of different germplasms and comparative effectiveness of morphological descriptors, floral and reproductive biology of three CPTs of annatto viz.,Tamil Nadu (green fruited), Kerala (red fruited), Karnataka (dark red fruited) at department of Forest Biology and Tree improvement, Forest College and Research Institute, Mettupalayam during 2017-19. A record on sequence of flowering ascends along the latitudes. The sequence of flowering is top to bottom (basipetal) that is the development, maturation or opening from the apex towards the base in the sequence. It commenced from the southern side to the south eastern side. The colour of the flower is whitish pink in Tamil Nadu, moderate pink in Karnataka and dark pink in Kerala and this floral colour polymorphism suggests that pollinators (mainly bumble bees and ants) are the primary selective agents which influence flower colour. The stain I-KI showed 95 % pollen viability and it is found that the viability of the pollen grains decreased after four hours from pollen dehiscence and tricolporate pollen was observed in annatto. The observation on fruit set indicated that bixa plant can have both self- and cross-pollination. Fruit maturity takes place 80 – 95 days counting from the day of pollination to fruit dehiscence. The shape of the fruit resembles rounded oblong pyriform. Maximum seed production was recorded in the red fruited (collected from Karnataka) (113.12 g) plant followed by the dark red fruited plant (Kerala) and the green fruited variant (TN).

The present study aimed at evaluating the genetic variability of different germplasms and comparative effectiveness of morphological descriptors, floral and reproductive biology of three CPTs of annatto viz.,Tamil Nadu (green fruited), Kerala (red fruited), Karnataka (dark red fruited) at department of Forest Biology and Tree improvement, Forest College and Research Institute, Mettupalayam during 2017-19. A record on sequence of flowering ascends along the latitudes. The sequence of flowering is top to bottom (basipetal) that is the development, maturation or opening from the apex towards the base in the sequence. It commenced from the southern side to the south eastern side. The colour of the flower is whitish pink in Tamil Nadu, moderate pink in Karnataka and dark pink in Kerala and this floral colour polymorphism suggests that pollinators (mainly bumble bees and ants) are the primary selective agents which influence flower colour. The stain I-KI showed 95 % pollen viability and it is found that the viability of the pollen grains decreased after four hours from pollen dehiscence and tricolporate pollen was observed in annatto. The observation on fruit set indicated that bixa plant can have both self- and cross-pollination. Fruit maturity takes place 80 -- 95 days counting from the day of pollination to fruit dehiscence. The shape of the fruit resembles rounded oblong pyriform. Maximum seed production was recorded in the red fruited (collected from Karnataka) (113.12 g) plant followed by the dark red fruited plant (Kerala) and the green fruited variant (TN). [ABSTRACT FROM AUTHOR]