Studies on the Control of Ascochyta Blight in Field Peas (Pisum sativum L.) Caused by Ascochyta pinodes in Zhejiang Province, China

Abstract

Ascochyta blight, an infection caused by a complex of Ascochyta pinodes, Ascochyta pinodella, Ascochyta pisi, and/or Phoma koolunga, is a destructive disease in many field peas (Pisum sativum L.)-growing regions, and it causes significant losses in grain yield. To understand the composition of fungi associated with this disease in Zhejiang Province, China, a total of 65 single-pycnidiospore fungal isolates were obtained from diseased pea samples collected from 5 locations in this region. These isolates were identified as Ascochyta pinodes by molecular techniques and their morphological and physiological characteristics. The mycelia of ZJ-1 could penetrate pea leaves across the stomas, and formed specific penetration structures and directly pierced leaves. The resistance level of 23 available pea cultivars was tested against their representative isolate A. pinodes ZJ-1 using the excised leaf-assay technique. The ZJ-1 mycelia could penetrate the leaves of all tested cultivars, and they developed typical symptoms, which suggested that all tested cultivars were susceptible to the fungus. Chemical fungicides and biological control agents were screened for management of this disease, and their efficacies were further determined. Most of the tested fungicides (11 out of 14) showed high activity toward ZJ-1 with EC 50 < 5 µg/mL. Moreover, fungicides, including tebuconazole, boscalid, iprodione, carbendazim, and fludioxonil, displayed more than 80% disease control efficacy under the recorded conditions. Three biocontrol strains of Bacillus sp. and one of Pantoea agglomerans were isolated from pea-related niches and significantly reduced the severity of disease under greenhouse and field conditions. To our knowledge, this is the first study on ascochyta blight in field peas, and results presented here will be useful for controlling the disease in this area.

Morphological and Genotypic Characterization of Fungi Associated with the Ascochyta Blight Complex in Western Regions of Algeria

“…The works of Wood (1967) and Wood (1969 and1971), reveal a physiological explanation of necrosis genesis caused by A. Pisi and A. Pinodes, but that it's not yet completely defined. However, Allard et al (1993), having worked on the pea anthracnose, consider in the same way that our results, that A. Pinodes and A. pinodella are resulting in similar damages (Na Liu et al 2016).…”

Spatiotemporal distribution of Ascochyta pinodes and Ascochyta pinodella during the winter growing season in France

“…() and Liu et al . () that A. pinodes and A. pinodella co‐occur on pea during the growing season. This study also shows, for the first time, that the prevalence of each species will change during the growing season and that both species could occur in the same niche.…”

“…Three of these pathogens have a worldwide distribution, while P. koolunga was recently described from Australia (Davidson et al ., ). Ascochyta pinodes and A. pinodella are the most common causal agents of ascochyta blight of pea and can co‐occur on the same pea plant causing foot rot and blight of leaves, stems, pods and seeds (Ahmed et al ., ; Liu et al ., ). Ascochyta pinodes is homothallic and readily forms pseudothecia (teleomorph Peyronellaea pinodes ) on senescent stipules later in the cropping season.…”

Recombinant Promoter (MUASCsV8CP) Driven Totiviral Killer Protein 4 (KP4) Imparts Resistance Against Fungal Pathogens in Transgenic Tobacco

“…Phoma , on the other hand, causes epidemic disease development in cabbage, Tasmanian pyrethrum and oilseed rape ( West et al, 2001 ; Pethybridge et al, 2005 ; Dilmaghani et al, 2009 ). Besides, it has devastating effects on field peas when associated with Ascochyta ( Liu et al, 2016 ). Recently, both Alternaria and Phoma were found to develop resistance against QoI or strobilurins and benzimidazole group of fungicides, respectively ( Van de Graaf et al, 2003 ; Karaoglanidis et al, 2011 ; Kim et al, 2017 ).…”