LIQUID SWINE MANURE FOR THE CONTROL OF MELOIDOGYNE JAVA']JAVANICA (TREUB) CHITWOOD

Liquid swine manure (LSM) is produced on a large scale in swine production and can be useful for the control of plant diseases. The effect of incorporation of LSM (0, 5, 10, 15, or 20%; v: v) into the soil for the control of Meloidogyne javanica on tomato plants was studied at soil pH levels of 5.0, 5.9, and 7.5 under greenhouse conditions. In a separate experiment, the interaction of three pH levels and five doses of LSM, with or without biofumigation (covering amended soil with plastic for seven days), was investigated. Increasing doses of LSM up to 20% increased shoot mass of tomato at all three pH levels. Amending the soil with 15.84% and 18.17% of LSM resulted in the lowest number of galls and eggs on tomato roots at soil pH 5.0. At soil pH of 5.9 and 7.5, the greatest reduction in gall and egg numbers varied from 5.26 to 5.55% and 3.85 to 8.33% of LSM amendment. There was a significant interaction for soil pH levels x LSM doses on the number of galls. A low level of galling occurred on plants from soil amended with LSM at doses of 17.22% (pH 5.0), 16.85% (pH 5.9), and 16.20% (pH 7.5). Increasing levels of LSM reduced the number of eggs in non-biofumigated plots at all pH levels. Soil amendment with 20% of LSM reduced the number of eggs of the nematode by more than 80%, and maximum suppression of nematode reproduction was observed in soils amended with 19.78% (pH 5.0), 16.08% (pH 5.9), and 15.33% (pH 7.5) of LSM. Soil microbial activity increased linearly in both biofumigated and non-biofumigated treatments with increasing levels of LSM at all pH levels. This study provides evidence that soil amendment with 12 to 14% of soil volume with liquid swine manure can reduce the population of M. javanica and improve tomato plant growth.