THE INFLUENCE OF MELOIDOGYNE INCOGNITA ON GROWTH, PHYSIOLOGY, NUTRIENT CONCENTRATION AND ALKALOID YIELD OF HYOSCY AMUS NIGER

Abstract

The effect of different inoculum level of Meloidogyne incognita on root-knot development, nematode multiplication, growth of the plant, total alkaloid yield, physiological responses (total leaf chlorophyll content, CO[sub2] exchange rate) and concentration of sodium, potassium, iron, manganese, copper and Zinc of Hyoscyamus niger 90 days after inoculation was determined. With the increase in inoculum level there was corresponding decrease in fresh and dry plant weight, total alkaloid yield, total chlorophyll content, photosynthetic rate, sodium, potassium, iron, manganese, copper and zinc concentrations in roots and shoots except for sodium and potassium which increased in shoot. The greatest percent reduction in all the characters was obtained when plants were inoculated with the highest nematode inoculum the relation between initial nematode population (Pi) and final nematode population (Pf) showed a maximum reproduction rate of M. incognita at Pi of 50 second stage juveniles.