IMPORTANT ENVIRONMENTAL FACTORS THAT INFLUENCE MELOIDOGYNE DEVELOPMENT

Certain environmental factors influence Meloidogyne spp development. They are moist soils and relative temperature. Some plants penetration by root-knot nematodes occurs between 10 and 35°c, with the optimum temperature at about 27°c depending on the species. Temperatures are broadly divided into five (5) arbitrary phases:-

(1)              Non-lethal-low temperatures at which activities is inhibited.

(2)              Optimum temperatures- nematodes are not affected by this

temperature, so the activities of the nematodes are at maximum.

(3)              Non-lethal high temperature at which activity is inhibited.

(4)              Lethal low temperature – the temperature can kill the nematode.

(5)              Lethal high temperature­-at high temperature, its nematode is killed

automatically.

Also water is one of the environmental factors that affect nematode population, extreme moisture conditions in the soil does not favor nematodes, example: flooding may kill the nematodes and they are used as one of the methods of control of nematode attack. Soil pores and aeration, which is the porosity of the soil and the oxygen and carbon dioxide content of the soil respectively are major  factors that influence nematode population and the rate of attack to our plants.

Chemicals in the soil solution may affect plant nematode population indirectly through plant growth and directly by acting as orientation stimuli. Also conditions like infected volunteer plants, monocultures, weeds in the fields, continuous growing of susceptible crops without rotation.