Breeding rice for drought-prone areas of eastern India, accomplishments in the recent past and current scenario
2009
Shrivastava, M.N. | Verulkar, S.B.
Rice is the staple food of millions of people and it plays a predominant role in determining their livelihoods. Eastern India, which comprises the states of Assam, Bihar, Jharkhand, Chhattisgarh, Madhya Pradesh, Orissa, eastem Uttar Pradesh, and West Bengal,and smaller states of the northeast region, accounts for 63.3% of the total rice area in the country. About 80% of this area is rainfed and is often exposed to abiotic stresses such as drought, low soil fertility, flood, and stagnant water. Although eastem India accountsfor about three-fifths of the total rice area, it produces only 48% of the total rice produced in India. The rainfed rice ecology in eastern India can be broadly classified into upland and lowland. Weed competition, frequent drought, low input application, high incidence of blast and brown spot diseases, and the lack of suitable varieties are the major problems faced in the upland ecosystem. In the lowland ecosystem, especially in the shallow lowland areas, high incidence of insect pests and diseases, weeds, terminal-stage drought, and unavailability of good-quality cultivars are the major constraints. Seedling-stage drought and submergence are major issues under semideep and deepwater situations. The coastal saline soils are often affected by iron and zinc deficiency, which causes chlorotic and low-tillering plants. The varietal improvement programs in the different eastem Indian states, which started in the first or second decade of the 20th century after the establishment of the Imperial Council of Agricultural Research in 1892 (and reoriented periodically), have led to the release of many improved varieties. Strategies for developing drought-tolerant, high-yielding varieties using conventional and molecular approaches are discussed in this paper.
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