evaluation of drought tolerance indices in potato (solanum tuberosum l.) cultivars

to study drought resistance indices of eight potato cultivars and to determine the most tolerant variety two experiments were conducted in the form of complete randomized block design with three replications (stress and non stress conditions) in 2002. seven indices ssi tol sti msti gmp tol and mp were used to determine tolerant varieties. it was found that mp sti gmp and msti were appropriate indices since they were correlated with yield in both stress and non stress conditions. using three dimensinal diagram four defined groups of fernandez were determined. the cultivars remarca ramus maradona and agria were high yielding in both conditions and were classified in group a. the results of biplot diagram and mp sti msti and gmp indices showed that ramus and remarca are the most tolerant varieties for drought stress conditions.