Genetic gain for yield in rice breeding and rice production in india to meet with the demand from increased human population.
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Our objective was to estimate genetic gain for yields in genotypes tested in 11 rice ecosystems from 1995 to 2013 in India and compare the growth trend of human population and national rice grain production in 1974 to 2013. In each ecosystem, the check used remained the same over years but showed similar and significant increases along with top-3 genotypes and experimental mean grain yields derived from sets of genotypes that varied with the year. Therefore, when environmental effects were eliminated, there was no significant genetic gain in yield of genotypes. Annually human population grew linearly at 16.203 million persons and rice production at 1.943 million tonnes (mt) during 1974-1994. This growth slowed during 1995- 2013 in population by 16.131 million persons and in rice production by 1.2753 mt. Breeding for higher genetic yields should be restricted to the four mega environments which offer scope, and exploit the unfolding advancements in rice genomics. The national average yield of un-milled rice was 3.76 t/ha. Evidence indicates that the potential yield in rice is 15-16 t/ha and yields of 10 t/ha is attainable in relatively riskfree irrigated (~20 m ha) and rainfed shallow lowland (11 m ha) ecosystems. Closing yield gap (~6 t/ha) through corrective technological and policy interventions is urgently needed to ensure rice availability to match with the demands of growing population.