170 V. G. Kakani et al.
Cultivars differed in their response to water stress treatments (Table 8.6). The in-
teractions persisted until the final harvest. Cultivar ICGS 11 recorded significantly
( p < 0.05) higher values for flower number (40 %), pod number (50 %), pod yield
(37 %) and harvest index (HI; 31 %), than TMV 2 under irrigated conditions (100 %
ETC). When the genotypes were supplied with 40 % ETC, the differences for toler-
ance to water stress were clear between the genotypes. Flower number, biomass,
pod yield and HI decreased by 14, 31, 42 and 14 % in ICGS 11 and by 0, 23, 28 and
4 % in TMV 2, respectively, compared to those obtained in the irrigated treatment.
There was no effect of water stress treatments or its interaction with genotypes on
peg and pod number and pod set.
8.3.6 Effects of Temperature and Its Interaction with Genotypes
Main effects of temperature were significant for biomass (Fig. 8.4). High tempera-
ture decreased biomass in T3 and T4 by 21 and 12 %, respectively, compared to
T1. The smaller decrease in biomass in T4 compared to T3 can be attributed to
lower VPD in T4. Similar trend was also recorded for vegetative weight (data not
presented).
The interaction of temperature treatments with water stress disappeared with
advance in crop age, but temperature interactions with cultivar persisted until the
Fig. 8.4 Seasonal time course of biomass ( diamond) and pod weight ( circle) recorded in water
stress treatments, Irri (100 % ETC—closed) and WS (40 % ETC—open) in T1 treatment; red
inverted triangle indicates start and end of high-temperature treatment, while blue inverted tri-
angle indicates start of water stress (WS—40 % ETC) treatment