Fig. 4.
First and second principal component scores (PC1 and PC2) for the identification of cotton cultivar response to temperature. The eigenvectors for variables are indicated by thick lines radiating from the centre showing the direction (angle) and magnitude (length) for maximum pollen germination (PG%; 2) and maximum pollen tube length (PTL; 1), cardinal temperatures (Tmin, Topt and Tmax) for pollen germination percentage (PG%max) (3, 4, 5) and pollen tube length (PTLmax) (6, 7, 8) and cell membrane thermostability as RI (9).