Effect of fly ash on growth, yield and root-knot disease of soybean

Abstract

An experiment was conducted to assess the potential of different levels (25-100%) of fly ash on growth and yield of soybean and on the root-knot nematode, Meloidogyne javanica. Low levels (25 and 50%) of fly ash enhanced plant growth and yield of soybean, which were greater at the 50% level. Further improvements in growth and yield were noticed at 50% of fly ash in the presence of Bradyrhizobium japonicum. At higher levels (75 and 100%) fly ash was phytotoxic. The presence of B. japonicum suppressed the numbers of galls, females and egg masses of the nematode but increased its fecundity. Root galling increased at 25 and 50%, but decreased at the 75 and 100% fly ash rates. Gradual suppression in egg mass production and fecundity were, however, observed at all levels of fly ash. The number of females of the nematode was increased at 25-50% levels, but at 75 and 100% levels fly ash was inhibitory for the nematode and no females developed at the highest level.