RESISTANCE TO CARMINE SPIDER-MITE IN WATERMELON

Resistance of 37 Citrullus lanatus L. lines to the carmine spider mite , Tetranychus cinnabarinus (Boisduval), was evaluated in three laborat ory experiments, each including seven plants per line. Infestation wit h ten adult female mites per leaf, of each plant, was done at the thre e-leaf stage. In experiment A, average counts 10 days after infestatio n of three leaves ranged from 42 to 144 mites per leaf. In experiment B, average counts 8 days after infestation of two leaves ranged from 4 0 to 286 mites per leaf. In experiment C, average counts 8 days after infestation of two leaves ranged from 15 to 196 mites per leaf. The re sults suggest that a definite variation in resistance against mite inf estation exists among watermelon lines.