The bacterial biocontrol agent pasteuria penetrans can help control root-knot nematode on sugarcane
Date
2018Metadata
Show full item recordAbstract
ROOT-KNOT NEMATODE (Meloidogyne javanica) is one of the most damaging pests of
sugarcane, often causing heavy losses in coarse-textured sandy soils. The bacterial
parasite Pasteuria penetrans is a potentially useful biocontrol agent and in a 2015–16
survey it was found at relatively high levels in three of the 126 sugarcane fields
surveyed. Soil was collected from one of the heavily-infested fields and a pot
experiment established to compare root-knot nematode multiplication in naturally infested soil and in soil where the endospores of P. penetrans had been killed by
autoclaving. After 37 weeks, the root-knot nematode population was very high in the
autoclaved soil but numbers of root-knot nematode eggs and second-stage juveniles
were 99% lower in the soil that was naturally-infested with P. penetrans. A subsequent
pot experiment with mass-produced endospores showed that when soil contained more
than 6 000 endospores/g soil, root galling was not as severe as in non-infested soil and
the number of root-knot nematode eggs was reduced by 71–82%. These results indicate
that when high endospore concentrations are continually maintained in the root zone, P.
penetrans will markedly reduce populations of one of the most important nematode
pests of sugarcane.