Ipm of Soybean Cyst Nematode in The Usa

Abstract

Abstract. The cropping system in the USA that produces soybean every other year exerts severe pressure on the production system. Unless the system changes dramatically to produce soybean every third or fourth year, severe pressure will be continue and will reduce the likelihood of sustainable soybean production. In the foreseeable future, genetic resistance of soybean coupled with crop rotation will be the foundation of any management system for Heterodera glycines. Marker assisted selection will aid in selection and incorporation of specific genes and will increase the efficiency of developing resistant cultivars. However, any source of resistance may not be durable even with sound nematode management practices. Rotation of resistance genes (sources of resistance) has met with some success and may increase durability of sources of resistance. Integrating biological control in the production system with promising organisms such as Hirsutella rhossiliensis and Pasteuria nishizawae may lead to a truly sustainable system of soybean production in which H. glycines is no longer a yield limiting production factor. 1. INTRODUCTION Although more than 100 species of nematodes have been associated with soybean in North America, only a few species are of economic importance (Donald et al., 1984; Noel, 1999). The soybean cyst nematode (Heterodera glycines) and root-knot nematodes (Meloidogyne arenaria, M. javanica, and M. incognita) are the nematodes responsible for most of the crop loss in soybean (Glycine max (L.) Merr.) in the USA., with M. hapla rarely causing economic loss. Crop loss caused by H. glycines was 2.91 million tonnes (t) in 2003, 3.48 million t in 2004, and 1.94 million t in 2005 (Wrather & Koenning, 2006). These losses were 31%, 28% and 28% respectively of the total crop loss due to diseases and nematodes and exceed any other disease. Crop loss due to individual species of Meloidogyne and other nematodes is not readily available. During the years of 2003–2005, the combined crop loss due to Meloidogyne spp. and all other species ranged from 106,000 to 139,000 t. Crop loss data is not readily available for the other major soybean producing nations Argentina, Brazil, and China. In recent years the incidence and distribution of the reniform nematode (Rotylenchulus reniformis) have increased in the southern USA. Nearly 100 species of nematodes have been associated with soybean (Schmitt & Noel, 1984; Noel, 1999). The Columbia lance nematode (Hoplolaimus columbus) is important in the states of Georgia, North Carolina and South Carolina, but also has been reported from Alabama and Louisiana. Hoplolaimus galeatus is found frequently in