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Efforts to enrich the varietal wealth in litchi with desired cultivars have been attempted. At ICAR-NRCL hybridization efforts have been emphasized for the past decades. The observed characteristic features and constraints encountered during the period were identified and systematic observations were taken. Studies show that the low genetic variability, small window of flowering period and stigma receptivity, small flower size, panicle injury, high flower and fruit drop, low seed germination and survivability are the prime hurdle that needs to be addressed. On average, the flowering period reported is 10–14 days which is even shorter during periods of increasing weather temperature. Across cultivars, the effective pollination period is very narrow and coincidence of stigma receptivity among cultivars was observed making it very challenging to attempt a maximum number of crosses within a short period. It was also observed that large numbers of small-sized and delicate flowers are produced in a panicle which injure the panicles during thinning and emasculation. Less than 3% of pollinated flowers were observed to attain fruit set which also registered low fruit retention during subsequent fruit development. The attack of seed borer at both the early and mature stages of fruit growth was noted which rendered the seeds non-viable. Parent incompatibility and very low success rate of hybrid seedling establishment were also observed especially in crosses involving small seeded parents like 'Bedana'. Here we present findings from a decade of experimentation on hybridization in litchi and document hurdles that come in the way of developing hybrids in litchi. Such information will be crucial for devising strategies for an effective litchi breeding programme. [ABSTRACT FROM AUTHOR]

An experiment was conducted in the year 2018 at ICAR-NRC on Litchi to investigate the effect of different pollen grain sources on fruit set and fruit retention in 'Bedana' litchi. The enclosed flower panicles of 'Bedana' were hand pollinated with male (M2) pollen from 'Shahi', 'China', 'Rose Scented', 'SwarnaRoopa' and 'Bedana' flowers. The current season's pollen as well as one year old pollen stored at 4 °C was used for pollination. The numbers of fruit set and fruit retention per panicle were determined throughout the fruit development period starting from pollination to harvest on a weekly basis. Initial fruit set was higher in all cross-pollination with pollen sources 'Shahi', 'China' 'Rose Scented' and 'Swarna Roopa' compared to self-pollination with pollen 'Bedana'. The final fruit retention in 'Bedana' was higher with all sources used for cross-pollination whereas there was no fruit retention in self-pollination where "Bedana" was used as source of pollen grains. Results indicated that cross-pollination in 'Bedana' litchi is essential for fruit set and fruit retention. The limited number of initial fruit set resulted in high retention of fruits (1.64% and 1.69%) in 'Bedana' with current season and one year old pollen of 'SwarnaRoopa'. It indicated that number of female flower should be restricted in a panicle for further pollination which would ensure good fruit retention at harvest. [ABSTRACT FROM AUTHOR]