REPRODUCTION OF MELOIDOGYNE INCOGNITA ON HYBRID RICE AND SURVEY OF PLANT-PARASITIC NEMATODES IN FURROW-IRRIGATED RICE IN ARKANSAS

Abstract

Furrow-irrigated hybrid rice production has increased in Arkansas and the mid-southern U.S.  The susceptibility of hybrid rice to Meloidogyne incognita, and the incidence and population density of plant-parasitic nematodes in furrow-irrigated rice is unknown.  Reproduction of M. incognita on hybrid rice was evaluated in three greenhouse pot experiments, and a nematode survey was based on soil samples collected after harvest from 16 furrow-irrigated rice fields.  All rice hybrids were susceptible to M. incognita race 3 but were less susceptible than soybean.  The susceptibility of four rice hybrids was consistent across three isolates of M. incognita, and the reproduction of the isolates was similar across hybrids. A 57% reduction in M. incognita reproduction was observed on subsurface-irrigated rice, which is similar to furrow-irrigated rice, compared to overhead-irrigated rice.  Spiral nematode (Helicotylenchus) and lesion nematode (Pratylenchus) were detected in 94 and 69% of furrow-irrigated fields sampled, respectively, and a low density of root-knot nematode (Meloidogyne) was detected in two fields.  Hybrid rice grown in a furrow-irrigated system can maintain a population of M. incognita and other plant-parasitic nematodes for the subsequent crop.