Using Soil Electrical Conductivity to Map Nematode-Prone Areas in Agricultural Fields

The root knot nematode (RKN), Meloidogyne incognita, is a damaging pest that causesmajor losses to the cotton industry annually. In Georgia, 60-70 percent of cotton fields are infestedwith this pest. Because application of nematicides is expensive and environmentally controversial,farmers put off applying the necessary chemicals. But RKN are not evenly distributed across fields.RKN populations have been shown to be higher in areas with higher sand content. Soil electricalconductivity (EC) can be used to characterize soil differences including soil texture. In 2005, a studywas begun to determine if data from a Veris 3100 soil EC sensor could be used to identify nematodehot spots in cotton fields in south Georgia. First year results were mixed. EC data comparedreasonably well with lab texture results, but did not correlate well with nematode counts in the fields(R values between 0 and 0.37). Additional analysis of collected data as well as additional data maybe required before hot spots can be reliably identified.