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A Short History of Rice Research in West Bengal

Carine PIONETTI

09 / 1997

The early rice research efforts, in the beginning of the 1930’s, aimed at improving the yielding capacity and quality of indigenous rice varieties. Throughout the country, indigenous rice germplasm was collected, evaluated, and improved through pure line selection or, to a lesser extent, through hybridization and mutation. The West Bengal department of agriculture released some sixty improved varieties between 1948 and 1960.

In the late 1950’s began a second phase of research based on the Indica-Japonica Rice Hybridization Project launched by the FAO in several countries. Indica and Japonica are the two most common rice types in the species Oryza sativa, the third one being Javanica. The proposed aim of the programme was to increase the ratio of grain over straw of the Indica type (of Indian origin)through a cross with the Japonica type (of Japanese origin). Yet, because of a significant difference in day length variation (Japonica featuring a 150 days maturation period compared to 50 days for Indica), the crosses resulted in sterile parents, and the project was abandoned.

The year 1962 was marked by the entry of the International Rice Research Institute (IRRI)in the field of rice research. After four years of work on intensive hybridization, a variety named IR8 was elaborated. This breeding material was evaluated at the Chinsurah Rice Research Station and tested in various governement adaptive trial farms. A full-fledged programme on high yielding varieties (HYV’s)was launched in India in 1965. It was to last until 1991. HYV’s were first released for irrigated areas, which at the time only represented less than 20% of the total agricultural land in West Bengal. Agro-packages, or ’minikits’, consisting of small cardboard boxes containing seeds, fertilizers and pesticides in sufficient quantity to cultivate some 50 square meters of new rice variety, were distributed from the 1970’s onwards.

Interestingly enough, between the early 1960’s and the early 1970’s, no serious research programme focused on the rainfed risk-prone areas, which represent over 70% of the rice-growing area in West Bengal. Until 1975, all the material that IRRI had to offer for adaptive trials was only suited for irrigated ecosytems.

The mid 70’s saw the emergence of a multiple crossing programme and a new effort to breed pest and disease resistance into HYV’s and emphasize the qualitative aspect of the grain. Research institutes were also mandated to release breeders’ seeds of popular improved local cultivars.

Adverse climatic conditions provided in the late 70’s the impetus for a new direction in rice research. The Southern districts of West Bengal suffered from a major flood in 1978. Dr. Biswas, then Head of the Chinsurah Rice Research Station, took that opportunity to collect and make a pure line selection of rice strands that had survived the flood. Their genetic make-up was used to increase the flood resistance performance of varieties growing in rainfed lowlands. Varieties featuring a long maturation period fare best in waterlogged areas. Extensive screening was therefore carried out to refine this trait. It is worthwhile to note that increasing maturation period had never been a concern at IRRI. In fact, all efforts aimed at shortening the maturation period of rice in order to achieve the target of three crops a year on irrigated land.

At Chinsurah and other stations throughout India, scientists engaged in cross-breeding work between the IRRI material and indigenous lines. The subcenters of Bankura, Purulia, Goshkara and Gosaba emphasized research on tolerance to drought, flood and salinity so as to develop location-specific high yielding varieties.

In 1992, new objectives were added to the rice research programme : development of hybrid rice for irrigated land, and genetic improvement of lowland rice.

A collection of some 10. 000 rice samples has been assembled at the Chinsurah station. Out of these, 5000 have been sent to IRRI and 2000 to the National Bureau of Plant Genetic Resources in Delhi for long-term storage, and 3000 are grown every year on the station farm.

Palavras-chave

agricultura, arroz, criação, política de pesquisa, revolução verde


, Índia, Ásia, West Bengal

dossiê

Biodiversité : le vivant en mouvement

Comentários

Efforts to increase rice productivity in rainfed cultivation came very late. This delay illustrates a bias in research which is mirrored in the Green Revolution strategy : the most resourceful regions received support in the pursuit of increased rice production while less ’progressive’ regions, both at the state and national levels, were till late left to their own devices. And this despite the fact that resource-poor subsistence farmers form the bulk of Indian farmers : research should therefore be directed at enhancing their locally adapted and low technology practices.

Notas

Personal study on biodiversity in India. A book is on the point to be published in India. For further information, please contact the author (see address)or Fph.

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