Table 1.
List of ex-PVP temperate introgressed, tropical lines (L1-L21) and single cross tester (T1-T8) parents used to form TWC testcross hybrids.
Fig 1.
Phenotypic distribution of testcross hybrids derived from tropical and temperate introgressed lines.
Fig 2.
Mean performance comparison of testcross hybrids from tropical and temperate-introgressed lines.
(A) Mean performance under well-watered (WW) and drought stress (DS) conditions compared using Student’s t-test. (B) Grain yield comparison under WW between hybrids derived from original tropical lines and their corresponding temperate-introgressed versions. The x-axis denotes the original tropical parental line used for introgression; TI_1–TI_5 represent the five temperate-introgressed derivatives.
Table 2.
Estimation of total variance components for grain yield and other agronomic traits evaluated under well-watered and water stress locations in Kenya.
Table 3.
Performance of top 10% (17) and lowest 5% (9) testcross hybrids for mean grain yield (GY, t/ha), days to anthesis (AD, days), days to silking (SD, day) anthesis silking interval (ASI, days), ear rot (ER), plant height (PH, cm), and ear height (EH, cm) under WW and DS conditions.
Fig 3.
Genetic variance components of testcross hybrids under contrasting moisture conditions.
(A) Proportional contribution of lines, testers, and line × tester interaction to total genetic variance for grain yield (GY), days to anthesis (AD), days to silking (SD), anthesis–silking interval (ASI), plant height (PH), ear height (EH), ear rot (ER), and gray leaf spot (GLS) under well-watered (WW) and drought stress (DS) conditions. (B) Proportion of additive (VA) and dominance (VD) genetic variance for grain yield and agronomic traits of 168 testcross hybrids under WW and DS conditions.
Table 4.
Line by tester analysis of variance of crosses for grain yield (GY), days to anthesis (AD) and silking (SD), anthesis silking interval (ASI), plant height (PH) and ear height (EH), ear rot (ER) and gray leaf spot (GLS) disease under well-watered and water-stressed conditions environments in Kenya.
Table 5.
Estimates of the general combining ability (GCA) of temperate introgressed, tropical lines and testers for grain yield (GY), ear rot (ER), days to anthesis (AD), days to silking (SD), anthesis silking interval (ASI), plant height (PH), ear height (EH) and gray leaf spot (GLS) under optimal (WW) and drought stress (DS) conditions.
Fig 4.
Cross-environment comparison of SCA effects for grain yield (GY).
(A) The ten hybrids with the highest and lowest SCA effects identified under drought stress (DS) and their corresponding SCA effects under well-watered (WW) conditions. (B) The ten hybrids with the highest and lowest SCA effects identified under WW and their corresponding SCA effects under DS conditions.