Abstract: The flow of rice genetic materials through 11 Indian research stations was traced by analysing the types of parents used in crosses during three periods: 1965–1967, 1970–1971, and 1974–1975. Breeding objectives of 1974–1975 crosses were determined.In 1965–1967, 80% of the crosses involved at least one semidwarf parent; TN1 was used in 41%, IR8 in 27%. By 1974–1975, 93% of the crosses involved semidwarfs. Use of TN1 and IR8 dropped sharply, but locally-developed semidwarfs were used in 67% of the crosses. Of the local semidwarfs, 45% were progeny of IR8, and 41% of TN1. Use of tall parents dropped, use of indica parents increased, and use of Japanese japonnicas and Taiwanese ponlais declined. Use of hybrids increased.The time lag from development of a strain until its adoption as a parent averaged 3.2 years. Time from first awareness of a rice until its adoption in a breeding program was 1.3 years. Most of their breeding materials were in local germplasm collections. The next most common method of acquisition was through trials.Yield potential, fertilizer response, and lodging resistance were breeding objectives for 80–90% of the 1974–1975 crosses. Improved grain quality was an objective of 69%; growth duration, 57%; disease resistance, 48%; insect resistance, 35%; cold tolerance, 13%; drought resistance, 7%; waterlogged-soils tolerance, 6%; and deep-water tolerance, 2%.Semidwarf rices were almost invariably used as parents for the yield—fertilizer response—nonlodging complex and were usually used as donors of disease- and insect-resistance. However, tall varieties were most often used as donors of preferred grain quality and maturity duration. Among semidwarfs used, Indian breeders tended to use locally-developed material as donors of desired grain quality and maturity duration traits, but about half of the semidwarfs used for pest resistance were from IRRI.Mean ratings of environmental and pest problems were compared with breeding objectives. Pests were a major problem in all areas; 67% of the crosses were for pest resistance. Drought was rated second, but only 7% of the crosses were for drought resistance. Of the specific pests, bacterial blight was named as a major problem in 71% of the areas; 22% of the crosses aimed for resistance to it. Stem borer was cited in 64% of the areas vs. only 6% resistance crosses.About 41% of farmers' fields were considered irrigated; 67% of the breeders' work was on irrigated rice; and 54% of the newest varieties were suited to irrigation. For rainfed lowland rice, the averages were: farmers' fields, 40%; scientists' efforts, 19%, and newest varieties, 33%.

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{{Explor lien
   |wiki=    Sante
   |area=    MersV1
   |flux=    Main
   |étape=   Exploration
   |type=    RBID
   |clé=     ISTEX:D1C5E38816A99B7F3D866A44128F281257A39B4C
   |texte=   The diffusion of genetic materials and the objectives for their use among rice breeding programs in India
}}