Effects of Co-inoculation with Pratylenchus thornei and Fusarium culmorum on Growth and Yield of Winter Wheat

Abstract

Hajihassani, A., Smiley, R. W., and Afshar, F. J. 2013. Effects of co-inoculation with Pratylenchus thomei and Fusarium culmorum on growth and yield of winter wheat. Plant Dis. 97:1470-1477.Growth and yield of winter wheat are suppressed by Pratylenchus thomei and by Fusarium culmorum. Many fields in cereal production regions throughout the world are infested by both pathogens. We evaluated effects of one or both pathogens on winter wheat growth, grain yield, and disease parameters at heading and harvest stages over 2 years in inoculated, rainfed pots incubated outdoors. P. thornei nematodes were inoculated at 1, 2, or 4 nematodes/g of soil and F. culmorum was added as colonized millet seed at 0.65 g/kg of soil. At harvest, compared with the noninoculated control, the high rate of P. thornei reduced {P < 0.05) plant height, shoot weight, root weight, and grain yield by 19, 17, 48, and 31%, respectively. F. culmorum alone reduced these parameters by 15, 16, 22, and 22%, respectively. Co-inoculations caused reductions of 27, 38, 61, and 63%, respectively. The reproductive rate of P. thomei was not greatly affected by co-inoculation with F. culmorum. Disease severity ratings at both plant growth stages became amplified as the nematode density was increased, and were much greater in the presence of both pathogens. Effects of co-inoculation on grain yield were slightly greater than predicted by additive effects of the individual pathogens, suggesting a synergistic effect on yield depression.Production of cereals is constrained globally by root diseases caused by plant-parasitic nematodes and plant-pathogenic fungi. Nematodes most commonly associated with economic damage to wheat {Triticum aestivum L.), barley {Hordeum vulgäre L.), and oat {Avena sativa L.) include the root-lesion nematodes Pratyletichus negiectus (Rench) Filipjev Schuurmanns & Stekhoven and P. thornei Sher & Allen, and the cereal cyst nematodes Heterodera avenae WolL, H. filipjevi Madzhidov, and H. latipons Franklin (35,43). Likewise, essentially all temperate cereal-production regions are infested by pathogens causing root diseases such as Fusarium crown rot {Fusarium culmorum (W.G. Sm.) Sacc. and F. pseudograminearum O'Donnell & T. Aoki), common root rot {Bi-polaris sorokiniana (Sacc.) Shoemaker), Rhizoctonia root rot {Rhi-zoctonia solani J.G. Ktibn AG-8), Pythium root rot (multiple species of Pythium Pringsheim), and take-all {Gaeumannomyces graminis var. tritici J. Walker) (39). The international literature is expansive for cereal diseases caused by these nematodes and fungi. However, most reports are focused upon the biology and management of a single causal agent. Reports of associations between species of nematodes, species of fungi, or of nematodes and fungi are much less common.Interactions between root-invading nematodes and root-infecting fungi have been known for more than a century (2). However, most reviews and individual reports have addressed interactions of nematodes with vascular wilt fungi such as Verticillium dahliae and F. oxyspor...

Monoxenic rearing of Ditylenchus weischeri and D. dipsaci and microplot examination of the host suitability of yellow pea to D. weischeri

“…(Faulkner & Darling 1961;Hussey & Krusberg 1971;Latif & Mian 1995). Callus induction from carrot disks has been used to rear migratory endoparasitic nematodes such as Pratylenchus vulnus (Moody et al 1973), P. thornei (Hajihassani et al 2013), Radopholus similis and Zygotylenchus guevarai (Verdejo-Lucas & Pinochet 1992), and D. dipsaci (Kühnhold et al 2006). Alfalfa callus tissue culture has been used for mass production of many plant-parasitic nematodes including D. dipsaci, P. penetrans, P. zeae, Bursaphelenchus lignicolus, and Aphelenchoides ritzemabosi (Krusberg 1961;Krusberg & Blickenstaff 1964;Riedel et al 1973;Tamura & Mamiya 1975;Verdejo-Lucas & Pinochet 1992).…”

Reação de genótipos de cana-de-açúcar ao nematoide das lesões radiculares

“…A quantificação do dano do nematoide nas raízes ainda é pouco estudada, e em alguns casos ocorrem outros patógenos associados que confundem os sintomas visuais e causam danos juntamente com o nematoide como, por exemplo, fungos do gênero Fusarium (Hajihassani et al, 2013), o que dificulta a avaliação visual do nematoide nas raízes. Assim, a contagens dos nematoides extraídos das raízes é mais precisa.…”

Interaction of root-lesion nematode (Pratylenchus thornei) and crown rot fungus (Fusarium culmorum) associated with spring wheat resistance under simulated field conditions

“…In wheat, limited information is available on Fusarium-RLN interactions. The association of F. culmorum with RLN species has been reported in some wheat-growing regions of Iran (Hajihassani et al, 2013), while F. pseudograminearum was reported to have a strong association with P. thornei, infesting cereal cultivars in a conservation farming system in Australia (Thompson & Clewett, 2021). Maximum yield loss was observed when P. thornei and F. culmorum were applied simultaneously (Hajihassani et al, 2013).…”