Combined Stresses in Plants: Physiological, Molecular, and Biochemical Aspects

166 V. G. Kakani et al.

8.3.2 Analysis of Variance

The ANOVA table (Table 8.2) for 2 × 3 × 2 (WS × Temp × Geno) split–split plot anal-
ysis with three replications at final harvest shows the main effects and interactions
between the treatments. No significant interaction could be recorded at final harvest
for temperature and water stress treatments. However, a significant interaction for
water stress and temperature was recorded for only peg and pod number in the
harvest made immediately after imposing high-temperature treatments (i.e. at 54
DAS). Otherwise, only main effects of temperature and water stress, and their inter-
action with genotypes, could be observed in the various harvests made for growth
analysis in the study. Hence, results recorded only at final harvest are presented.

8.3.3 Water Use and Water Use Efficiency

The cumulative amount of water supplied to IR (100 % of ETC) and water stress
(40 % of ETC) treatments is presented in Table 8.3. No monitoring was possible of
evaporation in the high-temperature treatments T2 (sowing1) and T4 (sowing 2).
Hence, similar amounts were supplied to ambient- (T1 and T3) and high-tempera-

Table 8.1 Average maximum (Max), minimum (Min) and mean air temperatures (°C), soil
temperatures (°C) and relative humidity (%) recorded during different developmental stages of
groundnut in the four temperature treatments to which the crop was exposed in the field
Devel-
opmen-
tal Stage

Treatments

T1 T2 T3 T4

Max Min Mean Max Min Mean Max Min Mean Max Min Mean

Max Min Mean Max Min Mean Max Min Mean Max Min Mean

Air temperature (°C)

Sowing–

R1

30.2 14.8 22.5 30.7 15.2 23.0 35.2 18.1 26.7 35.3 18.1 26.7

R1–R3a 33.9 16.5 25.2 41.6 17.4 29.5 38.7 20.3 29.5 43.5 18.05 30.8

R3–R8 37.8 20.4 29.1 38.6 20.3 29.5 38.6 23.7 31.2 38.6 23.7 31.2

Soil temperature (°C)

Sowing–

R8

25.8 25.3 25.5 29.4 26.2 27.8 25.9 25.2 25.5 32.3 25.2 30.8

Relative humidity (%)

Sowing

to R1

87.5 30.0 58.7 87.5 30.0 58.7 71.3 22.8 47.0 71.3 22.8 47.0

R1–R3a 73.3 22.2 47.7 NA NA NA 64.4 22.3 43.3 70.3 44.2 57.1
R3–R8 64.3 23.4 43.8 64.3 23.4 43.8 58.9 26.2 42.5 58.9 26.2 42.5
Developmental stages: R1 = Beginning flower; R3 = Beginning pod; R8 = Harvest maturity
NA not available
a High temperature period