Genetic analysis in Yardlong Bean [Vigna unguiculata (L.) Walp. subsp. sesquipedalis (L.) Verdc.]: A Comprehensive Review

Yardlong bean is a warm-season legume vegetables grown for its long green pods. It is a member of the Fabaceae family, and a subspecies of cowpea bearing exceptionally long, slender, and fleshy pods, occurs in a range of colors, including white, light green, dark green, reddish-brown, and purple. Despite its nutritional and agricultural value, the yardlong bean remains an underexploited legume crop. However, its dual role as a vegetable and leguminous plant highlights need of emphasis on genetic improvement and expansion of area under cultivation. A systematic literature search was conducted at Nalanda College of Horticulture, Noorsarai, Nalanda, to gather relevant information on work done so far on different aspect of crop improvement. Literature published between 1987 to 2026 was searched using academic Search Engine Databases. This manuscript was prepared by reviewing more than 50 papers. Yardlong bean cultivation faces several challenges, including the lack of improved varieties, limited extension services, low market prices, and the occurrence of pests and diseases. Breeding programs primarily aim to enhance pod yield per hectare by increasing the number of pods per plant. Other breeding goals include improving traits such as earliness, reduced vine length, photo-insensitivity, tolerance to biotic stresses and abiotic stresses and wide adaptability to different agroclimatic conditions. Predominance of additive gene effects for major yield attributing traits was recorded by many scientists, making phenotypic selection a promising and efficient strategy for crop improvement.