Plant Parasitic Nematodes of New Mexico and Arizona

Abstract

New Mexico and Arizona share topographic and climatic similarities that greatly influence crop production and plant parasitic nematodes in both states. The region is comprised of mountainous terrain interspersed with semi-arid, hot deserts, river valleys and plains. Crops are irrigated and grown mainly in the southern half of both states – within the northern reaches of the Sonoran (AZ) and Chihuahuan (NM) deserts. An exception is 29,160 ha of cropland in northwest NM operated by the Navajo Nation’s Navajo Agricultural Products Industry. Eastern New Mexico derives water from the western edge of the Ogallala Aquifer, but most cropland in both states relies on snow melt-derived water associated with river valleys. Mountain ranges and the Grand Canyon, in conjunction with numerous Native American homelands, US National Forests and federal Bureau of Land Management holdings afford a certain level of geographic isolation to many crop-producing areas. This isolation and the semi-arid environment have somewhat reduced the prevalence and introduction of some agricultural pests – undoubtedly including plant parasitic nematodes. Limited private arable acreage and irrigation water greatly affect grower decisions involving crop selection and sustainable nematode management. Southern root knot nematode (Meloidogyne incognita) is the most widely distributed and damaging plant parasite in the region, affecting most annual and some perennial crops. Other root knot nematodes including M. hapla, M. chitwoodi, M. graminis, M. marylandi and M. partityla damage some annual crops, turf and pecan. Ditylenchus dipsaci and Tylenchulus semipenetrans are pathogenic to alfalfa and citrus, respectively in Arizona, while criconematids have recently been associated with turf injury in New Mexico. Lesion nematodes (Pratylenchus spp.) affect cotton, corn and bean production in both states. This chapter focuses on the sustainable management practices for these nematodes within the context of cropping constraints associated with the region.