Rice is globally a major food crop and its production has progressively been affected by various types of abiotic stresses especially drought, flooding, salinity, heat and cold in most of the cultivable rice ecosystems. The incidence, intensity and duration of these stresses are anticipated to aggravate due to climate change consequences, demanding resilient yields in these situations to be essential. Present paper deals with reviewing various types of abiotic stresses and their mitigation strategies for enhancing and stabilizing rice production in stress prone areas. Review of available literature pertaining to the study area has been used as research methodology for this paper. The available literature suggests that stress-tolerant varieties can serve as the most viable strategy to contribute in coping with the problem of abiotic stresses. Although, good progress has been made in the development of stress-tolerant rice varieties (STRVs) and incessant efforts are being made to spread these varieties in target areas, adoption by farmers is yet to meet expectations. Advantage, affordability, awareness and availability are the main factors responsible for adopting of any technology. The adoption of stress-tolerant varieties has not reached its potential, predominantly due to the lack of awareness and non-availability of seeds amongst farmers. Strategic and intentional collaborations should be ensured for scaling the sustainable delivery and diffusion of STRVs. A promotional roadmap that ensures the linkages between private and public seed sectors remains the key factor for its successful adoption. Similarly, strengthening of formal, informal and semi-formal seed systems is crucial to accelerate the dissemination of these varieties. There is an imperative need to create strategic plans for the development of varieties possessing multiple stress tolerance. Significant investments for sustainability of rice production in stress prone areas form the essential component of long-term agricultural development. The sooner these investments and strategies are accomplished, the greater the gains are expected.

Twenty F1 hybrids from three CMS lines and eight pollen parents were evaluated to study the heterosis for various yield and quality traits in rice (Oryza sativa L.). The findings suggested that the magnitude of heterosis differed from character to character and cross to cross. Majority of the hybrids recorded desirable heterosis for grain yield. Among the rice hybrids exhibiting high heterosis for grain yield, IR-68897A x Pusa Sugandh-3, IR-58025A x HUR-JM-59221 and IR-58025A x Pusa Sugandh-5 were top performers. The hybrid, IR-68897A x Pusa Sugandh-3 recorded highest yield per plant, and was among the best three performers for traits, days to 50% flowering, days to maturity and number of effective tillers per plant. Thus, IR-68897A x Pusa Sugandh-3 may be considered as the best heterotic combination for yield and yield traits. Among the three high yielding hybrids, IR-58025A x Pusa Sugandh-5 was found to be relatively better performing for majority of the quality traits. Thus, IR-58025A x Pusa Sugandh-5 may be considered as the best cross combination if both yield and quality traits are taken into consideration.

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The present investigation in aromatic rice (Oryza sativa L.) was undertaken for studying the magnitude of heterosis in 28 hybrids (F1s) made by following 8x8 one way diallel mating design for yields and quality traits. Twenty eight hybrids were measured as per cent increase or decrease over the mean of better parent and over the checks using Pusa Basmati 1 and Taraori Basmati as best checks for yield and quality traits. For the trait days to 50% flowering and days to maturity, superior performer over better parents showed in cross: Pusa Sugandh-2 x Pusa Basmati-1and Pusa-2517-2-51-1x Type-3. Cross combination, Kasturi Basmati x Pusa -2517-251-1 performed superior over better parents and check for number of effective tillers/plant and main panicle length. The other crosses viz., Pusa Sugandh-5 x Pusa Sugandh-2 (kernel length), Pusa Sugandh-5 x Type-3 (amylose content) and Pusa Sugandh-5 x Pusa Basmati-1(Kernel Length, Kernel Length After Cooking, Length/Breadth ratio before cooking) exhibited significant heterosis for important grain quality traits. None of the high yielding hybrids recorded desirable performance over better parents and standard checks for all the yield and quality traits studied. Thus, these hybrids need to be further tested in observational/ multi-location trials before the commercial exploitation of its heterotic potential.