Gurdev S. Khush
Wolf Prize Laureate in Agriculture 2000
Gurdev S. Khush
Affiliation at the time of the award:
International Rice Research Institute, Philippines
“for his extraordinary contribution to theoretical research in plant genetics, evolution and breeding especially of rice, with regard to food production and alleviation of hunger”.
Dr. Gurdev S. Khush has had a marked impact in several research spheres in genetics and breeding. Below are three spheres of his long-term, sustained, innovative and exceptional scientific activity:
The area of cytogenetics, genomic constitution, evolutionary studies, chromosome additions (trisomics) and deletions (haplo), interspecific relations, linkage maps and their relation and orientation to specific chromosomes in the genome. Dr. Khush began his research in this area with rye (Secale), then continued with tomato (Lycopersicon) and for the last quarter of a century or so, he has focused on cultivated rice and related wild species (Oryza spp.). Dr. Khush has made remarkable contributions on the above, by developing new approaches and mobilizing new techniques, culminating with molecular ones. His contributions to rice cytogenetics and genetics are seminal. The genetic maps of molecular and traditional markers in rice are now very advanced. They also serve in synteny studies of the origins and evolution of other grain crops (e.g. wheat, maize and barley).
Over many years, Dr. Khush has developed an outstanding line of research focusing on understanding of the nature of plant resistance, mainly rice, to diseases and especially to insects. The latter is a much more problematic area, in which Dr. Khush´s achievements are exceptional. Using his basic genetic and biological research findings, he has been able to produce rice varieties resistant to several major insect pests, such as brown planthopper (Nilaparvata lugens), green leafhopper (Nephotettix virescens), whitebacked planthopper (Sogatella purcifera) and gall midge (Orseolia oryzae). Such verieties are more productive and also more eco-friendly. His research on the genetics of host-parasites interactions has led to the identification of numerous genes for disease and insect resistance, now utilized by IRRI and diverse national programs for developing pest resistant varieties. Khush has established complete series of primary trisomics of rice, utilized for the first time, for associating linkage groups with cytologically identifiable chromosomes. From the progenies of primary trisomics, he selected secondary and telotrisomics used for determining the orientation of linkage groups, positions of centromeres and arm location of genes and molecular markers. With his colleagues, Khush established the first molecular genetic map of rice, and has tagged many genes for disease and insect resistance and stress tolerance, with molecular markers. These advances are now used to apply molecular marker-aided selection in rice improvement. Dr. Khush has also investigated species relationships in genus Oryza, through cytogenetic and molecular approaches and transferred useful genes from wild species to cultivated rice.
The far-seeding aspect of Dr. Khush’s research activities centers on the development of a New Plant Type (NPT) of rice (sometimes labeled “super rice”). This calls for the design and mobilization of genes from cultivated rice and various wild species, to produce genotypes with more efficient photosynthesis, a better ratio of seed yield to straw and thus much higher yields and of better quality. A prototype in this NPT has already been developed and it is now being bred to diseases and pests.