The right rice in the right place: systematic exchange and farmer-based evaluation of rice germplasm for salt-affected areas.

Abstract

Traditional approaches for introducing improved rice varieties to farmers have demonstrated significant impact in favourable ecosystems in Asia, but with limited success in unfavourable ecosystems, as in saltaffected areas. Developing rice varieties with wider adaptation and broader tolerance of prevailing stresses is more viable for these areas, where abiotic stresses are particularly variable and complex, and growing conditions are too risky to persuade farmers to invest in inputs. The Challenge Program on Water and Foodsupported project (Project No 7) emphasizes the development and deployment of high-yielding, salt-tolerant rice varieties for coastal saline (Bangladesh, Vietnam and India), inland saline (Egypt and Iran) and sodic soils (India), where rice-based farming systems are being practised. Mostly, a superior performance of genotypes under experimental conditions does not guarantee their acceptance by farmers, and occasionally farmers reject genotypes that yield well if they do not satisfy their quality preferences. In view of this, a participatory varietal selection (PVS) approach, in which farmers participate in varietal screening and adaptation testing, was followed to accelerate the adoption of salt-tolerant varieties. The International Network for Genetic Evaluation of Rice (INGER), a global germplasm-testing platform coordinated by IRRI, is being used for the exchange of germplasm through the International Rice Soil Stress Tolerance Observational Nursery (IRSSTON). Promising lines were selected through PVS trials and some were released or nominated for release as varieties. Participating farmers increased their paddy yield from <2 t/ha to >3.5 t/ha, which encouraged neighbouring farmers to adopt these new varieties. Recently, BRRI dhan 47 was released as the first salttolerant variety for the boro (dry) season in the coast of Bangladesh. Progress has been made in reclaiming inland saline and sodic soils at Lucknow and Faizabad in India and CSR30, an aromatic fine-grain, salt tolerant variety, has recently become popular among farmers, besides other varieties. Proper management options for these salt-tolerant, high-yielding varieties have been developed and validated simultaneously in PVS trials. Introducing PVS has increased the adoption rate and helped to solicit systematic feedback from farmers, which has been a major guiding force in devising breeding strategies and in developing customized breeding materials.

Participatory evaluation guides the development and selection of farmers’ preferred rice varieties for salt- and flood-affected coastal deltas of South and Southeast Asia

“…The relatively low correlation in preference criteria between farmers and researchers during both wet and dry seasons indicated that farmers often had different priorities than the researchers, as also reported before ( Singh et al, 2010 ). Farmers’ preferences and their reasoning are important criteria for breeders to consider when developing new varieties to ensure they will be acceptable by farmers and adapted to local conditions.…”

“…This concern is particularly highlighted by the weak correlation between the preference scores of all farmers and grain yield, with the latter being a central criterion in most breeding programs. Apparently, farmers consider yield when selecting their most preferred varieties, but also other traits necessary for their local farming conditions ( Joshi et al, 1997 , Mandal et al, 2002 , Manzanilla et al, 2011 , Singh et al, 2010 , Singh et al, 2014 , Singh et al, 2016 ). Site-specific characteristics other than grain yield are expressly important in the wet season, as reflected by the significant correlations with yield in fewer trials than in the dry season (Tables 4 and 6).…”

“…Rice is a major crop in tropical coastal deltas in South and Southeast Asia. However, several climatic adversities including abiotic stresses like soil and water salinity in both wet ( Kharif ) and dry ( Rabi ) seasons, waterlogging or flash floods, coastal storms and cyclones during the wet season, often affects its productivity ( Burman et al, 2013 , Islam and Gregorio, 2013 , Ismail and Tuong, 2009 , Ismail et al, 2010 , Singh et al, 2010 ). Globally, about 230 million ha of coastal areas are saline ( Li et al, 2014 ) of which about 27 million ha are in coastal zones of South and Southeast Asia ( Ismail et al, 2010 ).…”

“…The PVS approach has been successfully implemented in marginal lands before, considering the social context of end users during evaluation, validation, and promotion of new varieties ( Joshi et al, 2007 , Joshi et al, 2012 , Manzanilla et al, 2011 , Morris and Bellon, 2004 , Ortiz-Ferrara et al, 2007 , Paris et al, 2001 , Paris et al, 2002 , Singh et al, 2010 , Singh et al, 2014 , Singh et al, 2016 ). It is designed to include viewpoints of resource-limited farmers, identify varieties suitable for different stress conditions and incorporate a wider range of traits that match specific client preferences ( Dorward et al, 2007 , Morris and Bellon, 2004 , Sperling et al, 2001 ).…”