Op. Yadav et Sk. Bhatnagar, Evaluation of indices for identification of pearl millet cultivars adaptedto stress and non-stress conditions, FIELD CR RE, 70(3), 2001, pp. 201-208
Pearl millet (Pennisetum glaucum) is cultivated across a wide range of envi
ronments ranging from extremely stressful to favourable. The objective of t
his research was to compare methods to identify productive cultivars for st
ress and non-stress conditions. Thirty pearl millet cultivars were evaluate
d at 22 locations that were grouped as stress, non-stress, or intermediate
environments. Five selection indices viz., arithmetic mean (AM), geometric
mean (GM), AM (standard units), stress susceptibility index (S) and drought
response index (DRI) were calculated for each genotype to determine correl
ation between selection indices and yield under stress (Y-S), non-stress (Y
-NS), and average conditions (Y-AV) Both cultivars and locations were signi
ficant sources of variation. Phenology of cultivars had different influence
on yielding ability in contrasting environments. While earliness was advan
tageous for stress conditions, cultivars with longer duration tended to yie
ld more under non-stress conditions. Y-S was only moderately determined by
Y-NS Both AM and GM were suitable indices for selection of cultivars that w
ould perform well across stress, non-stress, and intermediate environments.
Stress susceptibility index (S) was negatively correlated with Y-S (r = -0
.62**) but should only be used as a selection criterion in combination with
yield under stress (Y-S) to identify cultivars adapted to stress environme
nts. DRI was positively correlated with Y-S but had no association with Y-N
S. Results indicated that DRI might be useful for identifying cultivars wit
h high performance under stress particularly when days to Bower differ cons
iderably among test entries. (C) 2001 Elsevier Science B.V. All rights rese
rved.