Antibiosis of maize inbred lines to the carmine spider mite, Tetranychus cinnabarinus

The antibiosis of ten Zea mays L. inbred lines to the carmine spider mite, Tetranychus cinnabarinus (Boisduval) (Acari: Tetranychidae), was evaluated. Two maize inbred lines previously reported as resistant to this spider mit e and a susceptible inbred line were compared with B96 (formerly called 41: 2504B), reported as being resistant to the two-spotted spider mite T. urtic ae and to the European corn borer (Ostrinia nubilalis Hubner). Other lines were derived from B96. All lines originated in the U.S.A. and were tested i n Israel at two different growth stages. Four days after inoculation of det ached leaf squares with adult mites, significant differences in susceptibil ity were observed among lines. At the 3-leaf stage lines B68, B96, B79, A61 9, B65, B49 and B64 reduced the average mite daily fecundity by 43%, 64%, 6 6%, 67%, 77%, 81% and 87%, respectively, as compared with the most suscepti ble line, B52. At the flowering stage, the average reduction in mite daily fecundity was much lower: inbred lines B64, A619 and B96 reduced the averag e mite daily fecundity by 48%, 51% and 86%, respectively, whereas the seven other genotypes had an intermediate or a susceptible reaction to the carmi ne spider mite, with A661 being the most susceptible. Our results show that B96 could be used as a source of resistance in developing improved resista nce of inbred lines of maize to carmine spider mites.