Hybridization studies in citrus

Abstract

The experimental material consisted five citrus species viz., Katol gold, Grape fruit, Nucellar, Cutter Valencia and Natal orange in which the floral biology and crossing efficiency of citrus species was studied. The five citrus species were planted in randomized block design in four replications at research field of Santra Improvement Project, Horticulture Section, College of Agriculture and ICAR- Central Citrus Research Institute in Ambia Bahar 2023-2024. In sweet orange flowering takes place only once in year i.e. February-March. The duration of floral bud development was 19-23 days in different cultivars grapefruit was earliest to start flowering. The duration of flowering was 20-23 days in the cultivars. These cultivars came to full bloom in last week of February to first week of March. Two type of inflorescence were observed i.e. leafy and leafless. The flowers were borne on current season's growth in the axils of leaves either solitary or in cymes of three to eight. Flower structure observed in sweet orange with five sepals, five petals and twenty stamens with superior ovary. The maximum opening of flowers and dehiscence of anthers took place in morning hours (10.00 A.M. to 12.00 noon) in all the cultivars. Stigma became receptive just after anthesis and remained receptive till 72 hours of pollination in all the cultivars. The maximum receptivity was recorded on the day of anthesis. The highest fruit set was recorded in cultivar Katol gold under. The ‘Katol gold’ cultivar showed the highest percentage of fertile pollen, while the lesser fertile pollen was recorded in ‘Grapefruit’.