Soil properties influencing phytoparasitic nematode population on chilean vineyards

Abstract

Lifecycle of phytoparasitic nematode takes place in the rhizosphere, therefore their breeding, parasitism and mobility dynamics are inevitably influenced by the soil-root interaction, A study was performed to evaluate the influence of Vitis rootstocks to some plant parasitic nematodes under different soil conditions. Nematode populations were assessed in Vitis vinifera L. var. Chardonnay plants grafted on two rootstocks (K5BB, SO4) and ungrafted 'Chardonnay' as a control in three diferent alluvial soils in the central zone of Chile. Soils were two Inceptisols of the Casablanca Valley (Valparaíso Region), the first one without soil structure and with a densification zone in depth (S1) and the second one with sandy textural class (S3). A third soil was a Mollisol (S2) more structured than the others, situated on a locality of Melipilla (Metropolitan Region). The soils were characterized physically and morphologically and nematode genera were identified and counted using a dissecting microscope. 'Chardonnay' presented the highest population of Meloidogyne spp. on the three soil conditions but only significant in S2 soil. The population of Xiphinema spp. and Mesocriconema xenoplax were not representative enough to relate them with either soil or the different rootstocks. The amount of Meloidogyne spp. was inversely related with the sand content but positively related with the more structured soil. The stepwise regressions resulted useful when relating nematode populations with multiple soil factors.