Heterosis or hybrid vigor is a natural phenomenon where by hybrid off spring of genetically diverse individuals show advanced physical and purposeful traits relatively to their parents and off spring. Heterosis has been increasingly implemented in crop developed for nearly a century, with the purpose of developing greater energetic, better yielding and better appeared cultivars. In this review present and examine three classes of crop heterosis usage: intraspecific heterosis, intersubspecific heterosis and widehybridization heterosis, with specific recognition on polyploidy species. Different pollination control systems used to reproduce for heterosis also are comparatively analyzed. Finally issues worried in heterosis studies and crop development are to be highlighted. In the present review the ultimate goal to provide insight into first class practices for amplifying heterosis ability.

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Vembanad lake is the second largest brackish water lake in India and is known for its rich biodiversity. The study investigates the fish diversity, stake net fishing and seasonal variation in species distribution along the Puthenvelikkara backwaters of Vembanad Lake. A total of 30 sampling events using different gears were made during the period from January 2020 to February 2021. Total 2301 individuals were encountered, comprising 54 finfish species and 7 shellfish species from 34 families, 13 orders and 50 genera.Fish abundance peaked during pre-monsoon season, and the lowest were recorded in post monsoon season. Mugil cephalus, Penaeus indicus, Etroplus maculatus, Etroplus suratensis, Stolephorus indicus, and Ambassis ambassis were found to be the dominant species in the catch. Stake nets are predominantly utilized to target prawns, which waft with the tides. The Gross Energy Requirement (GER) was calculated to be 5.19 GJ.t fish -1 , which is surprisingly excessive for a stationary passively operated gear. The obtained energy efficiency ratio was 0.65, while the energy intensity value was 1.54. The high value of GER of this passively operated, non-motorized gear system is due to the low magnitude of landing by the gears.