ABSTRACT
Table 1 (p. 2) reveals a huge MV spread [CIMMYT, 1987; Dalrymple, 1986, pp. 2, 82-8; 1986a, pp. 2, 105-11]. Dalrymple estimates that in 1982-3, over 50 million hectares of wheat and over 72 mn ha of rice were planted in LDCs to ‘wheat varieties developed by CIMMYT, [rice varieties] developed by IRRI and CIAT and the offspring of those or similar varieties developed in national research programmes’. Almost all are semi-dwarf varieties, plus a few of intermediate height. They comprised 52 per cent of all wheat area, and 54 per cent of all rice area, in LDCs. A further 75-80 million LDC hectares were by the mid-1980s planted to maize MVs, defined as commercially purchased hybrids (or improved open-pollinated varieties) released in the past ten years. In all, about half the wheat, rice, and maize area in LDCs comprised MVs in 1985-6-as against almost nothing two decades previously [ibid., pp. 107-11].
