Seasonal variation of plant-parasitic nematodes and relationship with nutritional and growth properties of sugarcane plantations

The damage caused by Meloidogyne and Pratylenchus nematodes is included among the factors that limit growth and sustainability of sugarcane production. The objective of this study was to assess the seasonal changes and relationships between plant-parasitic nematode communities and plant variables (leaf chemical analysis and growth parameters) in sugarcane plantations in Pernambuco State, Brazil. Samples were collected at six, nine, and 12 months after planting in two sugarcane fields (plant cane and ratoon cane). Meloidogyne and Pratylenchus populations were extracted from sugarcane roots, counted and identified. Vegetative parameters that determine sugarcane growth pattern included stalk height, stalk diameter, and number of stalks and tillers. Leaf tissue was analyzed for potassium, phosphorus, calcium and magnesium contents. Meloidogyne and Pratylenchus abundance, plant nutrients and growth parameters in sugarcane plantations responded differently to environmental variation (i.e., temporal and sugarcane growth stage). Pratylenchus abundance decreased with the increase of leaf phosphorus content. Contrariwise, increases in potassium concentration resulted in high abundance of Meloidogyne. A positive association between the abundance of nematodes and sugarcane growth parameters suggest that the varieties planted in both study areas may present tolerance to Meloidogyne and Pratylenchus.