highly significantp = 2.56 × 10 −12
The effects of instar, direction of photoperiod shift and their interaction were highly significant ( χ 2 = 63,27, d.f. = 5, p = 2.56 × 10 −12 , χ 2 = 125,87, d.f. = 1, p < 2.2 × 10 −16 , d.f. = 5, χ 2 = 14,18, p = 0.015, respectively).