Seed borne nematode of small millets: A review

Abstract

Among seven small millets, only foxtail millet (Setaria italica) and proso millet (Panicum miliaceum) were found infested with a seed borne nematode, Aphelenchoides besseyi. Basically, the nematode is a serious pest of rice and causes whip tip of paddy, but significant infestation was also recorded in foxtail millet and proso millet. Green foxtail millet (Setaria viridis), crab grass (Panicun sanguinale) and guinea grass (Panicum maximum) were also found infested with A. besseyi. It causes Ear blight or Light ear disease in foxtail millet. Characteristic symptoms of nematode infestation were distortion and spreading of panicles, production of chaffy grains and delayed maturity. Maximum nematode population was recorded in the seeds having black seed coat and abnormal seeds of both the millets. Variation in morphology and morphometric attributes of nematodes was recorded among rice, foxtail millet and proso millet isolates. Amphimictic mode of reproduction was reported in the populations of A. besseyi in foxtail and proso millet. More survival of nematode was found in proso millet as compared to rice. Auxenic culture of Alternaria alternata and Curvularia lunaat supports the growth and reproduction of A. besseyi in proso millet. Number of females over one male was maximum in foxtail millet (5.25) followed by rice (3.41) and proso millet (3.16). Lowest population of nematode was recorded in foxtail millet cultivars RFM 21, 23, 51, 68, 74, 76, 84, 99, SiA 3156 and SiA 3190. and proso millet cultivars DHPM 50-1-1, TNAU 137, TNAU 149, TNAU 151, TNAU 183 and TNAU 191. Adverse effect of herbicides viz. Propaquizafop and Bispyribac sodium on survival and mortality of A. besseyi was observed.