Effects of Metam Sodium and Rootstock on Plant-Parasitic Nematodes, Tree Growth, Yield, Fruit Quality, and Leaf Minerals in 'Braeburn Apple

Abstract

Effects of two levels of metam sodium [methyl isothiocyanate (Vapam, 33% a.i., v/v)] and five root-stocks on plant-parasitic nematode populations, trunk cross sectional area (TCSA), yield per tree, yield efficiency (yield per tree/TCSA), fruit weight, color, sunburn, and leaf minerals in 'Braeburn apple (Malus domestica Borkh.) were studied. Metam sodium treatments suppressed different parasitic nematode populations. Trees receiving low or high metam sodium treatments (Vapam at 748 L/ha or 1496 L/ha, respectively) had significantly larger TCSA than those of the un-treated control one year after application. Two and three years after applications, trees from the high metam sodium treated areas had higher TCSA than those with lower metam sodium and trees in both of these treatments had significantly higher TCSA than control trees. Yield efficiency in trees with both rates of metam sodium was similar, and was greater than that of the controls two and three years after planting. Both rat