COMPARISON OF DL- Β-AMINO-N-BUTYRIC ACID, SALICYLIC ACID AND ABSCISIC ACID IN INDUCTION OF RESISTANCE IN TOMATO INFECTED BY MELOIDOGYNE INCOGNITA

The effect of several levels of DL-β-amino-n-butyric acid (BABA), salicylic acid (SA) and abscisic acid (ABA) on induction of systemic resistance against root-knot nematode, Meloidogyne incognita, in tomato was studied under growth chamber conditions. The experiment was laid out as completely randomized design with three replicates. Tomato (Solanum lycopersicum cv. Moneymaker) was planted in 1 kg plastic pots. At 4-leaf stage, foliar sprays and soil drenches were applied with 0, 0.25, 0.5 and 1 mM of SA and BABA. Foliar spray was also conducted with 0, 50, 100 and 200 µM of ABA. After 24 hours, pots were inoculated each with 1.3 J2 of the nematode per g. of soil. Plant and nematode related parameters were evaluated 60 days after inoculation. The data showed that none of the inducers had significant effect on plant growth indices. On the contrary, different levels of inducers significantly reduced nematode indices including number of galls, egg masses and eggs on root, number of eggs in egg masses and the reproduction factor in induced plants. The reproduction factor decreased about 60% in plants treated with 0.5 mM of SA and BABA and 17% in plants sprayed with 100 mM of ABA.These results indicate that root-knot nematode, M. incognita, can be controlled by application of SA, BABA and ABA, in tomato.