Fig. 2. Effect of culture medium and variety on (A) callus weight, (B) plantlet regeneration, (C) NPR/Cal, and (D) and NPR/RCal of MEs of durum wheat. Use of the same letter “a,” “b,” and/or “c” above the bar indicates that the results are not significantly different at α = 0.05 according to the LSD test. LSD: least significant difference according to the t-test; ME: mature embryo; NPR/Cal: number of plantlets regenerating per callus; NPR/RCal: number of plantlets regenerated per regenerating callus