New hosts of Heterodera cruciferae Franklin, 1945 in vegetable farmlands of Tabriz, Iran

 

 
Traditionally, in suburbs of Tabriz city, northwest Iran (GPS 38˚06΄N, 46˚15΄E, mean temperature of 6.6-20.0°C, sandy loam soil type), different types of vegetables including cabbages have been cultivated for many years. The cabbage cyst nematode, Heterodera cruciferae was reported as one of the plant parasitic nematodes infecting kohlrabi (Brassica oleracea L. var. gongylodes) and white cabbage (Brassica oleracea L. var. captita alba) in the region. Besides these plants, brussels sprouts, cauliflower, broccoli, radish and  Alyssum maritimum, Crambe maritime, Cheiranthus allionii, C. cheiri, Iberis umbellate, Lepidium sativum, Raphanus sativus, Sinapis alba, Lamium album, L. purpureum, Stachysannua, Alyssum montanum, Lunaria annua, Moricandia arvensis and M. sonchifolia, carrot, pea, potato, sweet sop (Annonas quamosa), sugar beet and garden beet, are known as hosts of the H. cruciferae worldwide.
During a study on the life cycle of cabbage cyst nematode on its main hosts in the region, 2012-2013, several vegetable crops and different weeds were sampled and checked for the possibility of infection with the cyst nematode. The roots of the plants were stained using lactoglycerin-acid fuchsin solution, examined under stereomicroscope and different developmental stages of the nematode monitored. The morphological and morphometric characters of cysts were determined. As a result, the plants Coriander (Coriandrum sativum L., Umbelliferae), Sonchus (Sonchus asper (L.) Hill., Asteraceae) and Sisymbrium loeselii L. Brassicaceae were found as naturally infected hosts of the cabbage cyst nematode (Fig 1) and herein are reported as new hosts of H. cruciferae. According to available literature, there is no previous documentation of these plants as hosts of the nematode. Other plants such as Chenopodium album, Raphanus sativus and Lepidium sativum found that are infected by the cabbage cyst nematode in the area, too.