The Relationships Between Plant Parasitic Nematodes of Sugarbeet And Other Soil Fauna

INTRODUCTION ------------------------------------------------------------- -1- INTRODUCTION sugarbeet, beta vulgaris saccarifera L. is considered one of the most important crops that rank next to sugarcane in importance as sugar crop in Egypt and attribute 28 % of sucrose production. In Egypt, sugarbeet is cultivated in 153.8 thousand faddans with an average production of 20.6 tons per faddan (2001/2002). In the recently, reclaimed desert irrigated lands at West Nubaryia and El-Bostan regions has shown that sugarbeet can be successfully grown under sandy soil area condition. Plant parasitic nematodes, especially root-knot nematodes are known among the most serious pests of sugarbeet in many countries. Of some 50 described species of Meloidogyne, only few parasitized sugarbeet, viz, M. arenaria, M. incognita, M. javanica, M. hapla and M. naasi are economically important to sugarbeet production (Arnold, 1984 ). M. arenaria, M. incognita and M. javanica essentially are hot –weather organisms and most important where beets are grown in regions with long, hot summers and short, mild winter. In Egypt, M. incognita and M. javanica were reported as major nematode pests of sugarbeet (Oteifa and El-Gindi, 1982; Abd El-Massih, 1985; Maareg et al., 1988 a&b and 1998 and Ismail et al. 1996). The average annual loss in yield of sugarbeet due to M. incognita in different states in the U. S. A. was estimated to be as high as 10-50 % and in Italy as 5-15 % (Altman and Thomson, 1971). No estimation for loss in sugar content due to M. incognita was reported. Yield loss estimates were based on nematode population, on curves derived earlier relating nematode