Karuna, KumariMandal, Sunil Kumar2020-03-092020-03-092019-04http://krishikosh.egranth.ac.in/handle/1/5810145021Mango (Mangifera indica L.) is the most important fruit crop of India having socio-economic significance. Its place of origin is supported to be near Indo- Burma region. India leads the world in terms of area and production. It has been the traditional exporter of mango. However, it exports only 0.2 percent of its total production to the international market. The Indian mango for export is mainly confined to cultivar Alphonso (about 90 %). The current trend is to develop coloured variety of mango for export purposes. The colour of the fruit with desirable qualities enhance the cousumers appeal. The existing varieties appear to have been selected for the character like fruit size, quality and maturity period. These informations are helpful in planning the hybridization programme also. Although the bearing behaviour of a fruit crop is a genetical character, it is highly influenced by the environmental factors too. Therefore, the adaptive trial can be helpful in giving the idea of acclimatization of a variety to a particular region. So, the importance of present investigation was undertaken to study the “Floral Biology, pollen viability, and compatibility study in some cultivars of mango (Mangifera indica L.)” under Sabour conditions. For this, six varieties were taken in the experiment. Three commercial cultivars of mango viz; Langra, Amrapali, Zardalu and three coloured mango Gulabkhas, Vanraj, Hussan-e-ara were crossed during the course of study in Horticulture Garden of Bihar Agricultural , Sabour in the year 2018. The experiment was laid out in Randomized Block Design with four replications on 20-25 years old trees. The results indicated that the duration of panicle initiation was highest (45 days) in Langra and was found lowest (34.7days) in Amrapali. Among all cultivars Zardalu was recorded maximum panicle length (38.4cm) and minimum (23.4cm) in Langra. Flowering period much more affected by the climate and in the same condition significantly maximum (27 days) was recorded in Hussan-e-ara whereas minimum (22 days) in Gulabkhas and rest of the treatments were found non-significant result. Anthesis per cent were recorded from 6.00 AM to 4.00 PM at the interval of 2 hours. It was found that highest per cent of anthesis was occurred during 6.00 AM to 10.00 AM and then after decreases the per cent of anthesis in all cultivars. Data regarding to number of flowers per panicle were highest in Langra (1003) among all six cultivars whereas lowest in Vanraj (782). In respect of number of staminate flowers it was found significantly maximum in Langra (705) and minimum (480) in Vanraj and rest of the treatments varies from 560 to 609. Number of perfect flowers were also maximum (298) in Langra and minimum (208) in Hussan-e-ara. Sex ratio is an important parameter for determination of fruiting behaviour and ultimately yield. Highest sex ratio(2.7) were recorded in Gulabkhas and Hussan-e-ara, whereas lowest (1.5) in Vanraj. For hybridization programme pollen viability as well as pollen germination per cent are an important parameters. Highest pollen viability per cent (90.6) was in Hussan-e-ara which was at par with Amrapali whereas lowest (77.2) per cent in Zardalu which was at par with rest of the treatments. Pollen germination per cent was maximum (69.7) in Hussan-e-ara which was at par with Amrapali and minimum (60.20) per cent in Zardalu which was at par with rest of the treatments. In cross combination highest per cent of fruit set (20) was recorded in Amrapali x Vanraj which was at par with Amrapali x Hussan-e-ara whereas lowest (8) per cent in Langra x Vanraj. On the basis of above results it may be concluded that maximum compatibility among the cultivars for fruit set were observed in Amrapali x Vanraj.ennullThesis