Intercropping and Nitrogen Fertilization Altered the Patterns of Leaf Senescence in Sorghum
Table 3
Correlation coefficients between senescence traits and sorghum grain yield and yield parameters of two sorghum varieties (Gadam and Serena) grown in an intercrop system with two varieties of cowpea (K80 and M66) at 0, 40, and 80 kg·N·ha−1 during 2018/2019 short rains at the KALRO research stations in Igoji and Katumani during the 2018/2019 short rain season.
Cropping system
Traits
Igoji
Katumani
SPADmax
SPADmin
EC50
RS
SPADmax
SPADmin
EC50
RS
Sole
Grain yield
0.82
0.92
−0.14 ns
0.93
0.77
0.82
0.05 ns
0.75 ns
Panicle length
−0.53 ns
0.94
−0.19 ns
0.79 ns
−0.39 ns
0.09 ns
0.38 ns
0.33 ns
Panicle width
−0.53 ns
0.55 ns
0.32 ns
0.32 ns
0.89 ns
0.96
0.42 ns
−0.24 ns
Panicle weight
0.18 ns
0.9 ns
0.16 ns
0.72 ns
0.44 ns
0.25 ns
0.43 ns
−0.18 ns
1000-seed weight
0.71
0.5 ns
0.18 ns
0.81 ns
0.95
0.76
0.51 ns
−0.07 ns
Intercrop
Grain yield
0.58
0.75
0.13 ns
0.03 ns
0.76
0.89
0.15 ns
−0.07 ns
Panicle length
0.10 ns
0.001 ns
−0.05 ns
0.34 ns
0.44 ns
0.46 ns
0.09 ns
0.38 ns
Panicle width
0.45 ns
0.37 ns
0.51 ns
0.26 ns
0.52 ns
0.37 ns
0.22 ns
0.10 ns
Panicle weight
−0.57 ns
−0.55 ns
−0.37 ns
−0.04 ns
0.10 ns
0.13 ns
0.14 ns
−0.003 ns
1000-seed weight
−0.31 ns
−0.28 ns
−0.50 ns
0.11 ns
0.14 ns
0.005 ns
0.20 ns
0.27 ns
SPADmin: minimum leaf greenness; SPADmax: maximum leaf greenness; EC50: time to loss of 50% SPADmax; RS: rate of senescence; ns: not significant; ;;n = 54.