*2.2. Parental Lines Screening*

Fourteen tetraploid cotton cultivars were chosen, named CIM-557, CIM-573, NN-3, Cyto-108, NIAB-852, CIM-588, BH-172, GH-102, NIAB-2008, MNH 886, CIM-554, Shahbaz-12, MNH-2007, and MNH 814 for altogether 23 morphological and physiological characteristics, viz Total Plant Height (TPH), Fully Dehiscent Anther (%) (FDA), Total Number of Sympodes (TNS), Total Number of Nodes (TNN), Pollen Viability (%) (POV), 1st Sympodial Node number (FSN), 1st Sympodial node Height (cm) (FSH), Sympodial Node number having 1st effective boll (SNF), Sympodial Node Height (cm) having 1st effective boll (SNH), Sympodial Node Number having Last effective boll (SNN), Sympodial Node Height (cm) having last effective boll (SNH), Percent boll set on 1st position with sympodia (PBF), Percent boll set on 2nd position with sympodia (PBS), Cell Injury (CIY), Number of Bolls (NOB), Total number of buds (TNB), Size of Petiole (SOP), Total Number of Flowers (TNF), Length of Bract (LOB), Length of Petal (cm) (LOP), Length of Staminal column (LOS), Length of Pistil (LPI), and Proline Con. (μg mL−1) (PCO), contributing to heat tolerance to identify the genomic regions. Arithmetic means of three replicates were calculated for fourteen cultivars for each characteristic. The data were compared. The variance and standard deviation were also calculated. The computation of trait correlation was carried out using Minitab Inc., University Park, PA, USA and the following shortlisted traits had considerably varying phenotypes among two genotypes, i.e., MNH 886 and MNH 814 (Figure 1).

**Figure 1.** *Cont.*

**Figure 1.** Mean values of phenotypic variations of morpho-physiological traits related to the heat stress of 14 cotton genotypes.
