The effect of initial population densities of Xiphinema index on the growth of grapevine

Abstract

The effect of initial population densities of Xiphinema index on the growth of grapevine (Vitis vinifera D.C.) cv. Aglianico was studied in a glasshouse at 21 ± 2°C. Grape seedlings were transplanted in plastic pots containing 160 cm3 of soil and inoculated with 0, 0.31, 0.62, 1.25 ... 640 X. index/l0 cm3 of soil. Fitting the data to the equation y = m + (1 - m) ZP-T indicates a tolerance limit of grapevine to the nematode of 1.7 individuals/l0 cm3 of soil and a relative minimum yield of 0.05. Final populations of the nematode were larger at lower initial densities, the rate of multiplication decreased with the increase of the initial population and an equilibrium density of 46.7 was estimated.