Reproduction of Meloidogyne incognita on Open-pollinated Maize Varieties

Forty-three open-pollinated maize varieties were tested for resistance to the southern root-knot nematode, Meloidogyne incognita race 4, in greenhouse tests. An experiment repeated on five different planting dates assessed nematode reproduction 60 days after inoculation with 3,000 eggs per plant. Tebeau and Old Raccoon showed consistently high levels of resistance in all plantings, with the lowest reproduction factor (RF) values (0.2 and 0.4) and low numbers of eggs per gram of fresh root (222 and 955). Bill Dailey Variety and Sheppard Corn had the same level of resistance to M. incognita as the resistant hybrid, Mp307 x Mp707, but they were less consistent in different plantings. Levi Mallard, African Bushman, and Field's White Variety were the most susceptible varieties with RF values of 3.1-3.3 and 2,479-3,678 eggs per gram of fresh root.