Grafting is a simple method of propagation in which desired rootstocks are obtained to induce vigor, precocity, enhanced yield and quality, better survival under biotic and abiotic stress conditions. Grafting reduced the dependency upon chemicals required to treat the soil borne diseases and has opened new vista in organic farming of vegetables. Grafting is the popular technology among vegetable growers and researchers to develop resistance in the crops or improve tolerance to biotic and environmental stresses in the various crops mentioning solanaceous and cucurbitaceous crops. The technology of grafting is potential in promoting the cultivation of vegetables in customized and fragile agricultural-ecosystem. It is a alternative tool which is rapid in case of relatively slow breeding methodology and useful in sustainable horticulture which takes low input for future agriculture system. Further, inventions in mechanized and robotic grafting have given a fillip to this novel eco-friendly approach. Mechanization will considerably reduce the cost of grafted seedling production in the future.

The development of fruits without fertilization is known as parthenocarpy. Parthenocarpy improves the fruit quality, processing attributes, production and productivity of vegetable crops like tomato, cucumber, watermelon etc. Absence of seeds can enhances the shelf life of the fruits, allowing a better conservation, fruit set in adverse climatic conditions, early and offseason production of vegetable crops. Therefore, it is important to ensure yield stability regardless of environmental conditions. Breeding of new cultivars with the ability to develop fruits without pollination or any artificial stimuli is a promising approach. Parthenocarpic vegetables can be natural or can be induced artificially by various methods like, use of plant growth regulators, distant hybridization, mutation, use of irradiated pollen, alternation in chromosome number, gene silencing, gene modifications and genome editing tools. Therefore, present review is focused on genetics, nature of gene action, mapping of QTLs and various breeding methods to induce parthenocarpy in vegetable crops.

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Genetic divergence among forty four genotypes of paprika was assessed using Mahalanobis D 2 statistic for twenty characters at Horticultural Research Station, Lam, Guntur, Andhra Pradesh. The analysis of variance revealed significant differences among the genotypes for all the characters studied indicating considerable diversity in the material. Based on Mahalanobis D 2 statistic, the forty four genotypes were grouped into 6 clusters. The maximum contribution towards genetic divergence was by total extractable colour (21.56%) followed by red carotenoids (19.87%), yellow carotenoids (13.95%), ascorbic acid (7.29%). Among the clusters, clusters III was the largest containing 17 genotypes followed by cluster II (15) and cluster I (9), whereas the clusters IV, V and VI were solitary clusters. The highest inter cluster distance was observed between cluster V and VI (1675.44), whereas the lowest was observed between cluster I and II (217.58). Cluster III (275.34) has exhibited highest intra cluster distance and the lowest was observed in clusters IV, V and VI (0.00), respectively. Cluster analysis by Tocher's method revealed wide genetic distance (inter cluster) between the genotypes of cluster V (Byadagikaddi) and the cluster VI (Warangal chapatta double patti) and the crossing between genotypes of these two clusters can be exploited for the development of heterotic hybrids in future breeding programmes.

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