Published in Tropical Plant Pathology
Wheat blast, caused by the fungus Magnaporthe oryzae Triticum (MoT) pathotype, is one of the most important yield-reducing diseases of wheat, mainly in the tropical wheat-growing regions of South America. In this study, we assessed the effects of nitrogen (N) fertilization on wheat blast epidemics. Factorial experiments were carried out in Londrina...
Published in Tropical Plant Pathology
This study aimed at evaluating the variability in resistance of common bean progenies and plants to diseases caused by Pseudocercospora griseola and Colletotrichum lindemuthianum. It also sought to infer whether S0 plants were heterozygous for the possible resistance loci and the frequency resistant plants varies with the bulk opening generation. P...
Published in Tropical Plant Pathology
In vitro culture of sand pear (Pyrus pyrifolia) cv. Huanghua (HH) infected with apple stem grooving virus (ASGV) was conducted and the titer and variant mutations of the virus in sub-culture were analyzed. The results showed that ASGV could replicate stably in 20 successive sub-cultures. The 500 bp PCR products of ASGV in each sub-culture were clon...
Published in Tropical Plant Pathology
In the current study 27 plant growth-promoting rhizobacteria (PGPR) strains were screened for biocontrol activity against Meloidogyne incognita on 6-week old carrot seedlings that were inoculated with a suspension of J2 juveniles five days after treatment with the bacteria. Five of the PGPR strains, namely Bacillus firmus T11, Bacillus aryabhattai ...
Published in Tropical Plant Pathology
Identification of Meloidogyne spp. is challenging when using only the classical techniques since some species share similar characteristics. In this study, 37 Meloidogyne populations were obtained from four provinces in South Africa during 2015 and 2016 and molecularly characterised. We used SCAR-PCR markers and sequencing of four DNA fragments, vi...
Published in Tropical Plant Pathology
Citrus Huanglongbing (HLB) management relies on adoption of preventive measures including the use of healthy nursery trees, area-wide control of the vector Diaphorina citri, and eradication of symptomatic trees. Cultural practices including tree density could contribute to HLB management. We investigated the role of tree density on the incidence of...
Published in Tropical Plant Pathology
One of the most important virus diseases in tomatoes in Brazil is caused by isolates of tomato chlorosis virus (ToCV, Tomato chlorosis virus, genus Crinivirus, family Closteroviridae). ToCV has a bipartite genome which is encapsidated in filamentous particles. RNA1 encodes an RNA silencing suppressor, the protein p22, that has been described as a h...
Published in Tropical Plant Pathology
Cassava (Manihot esculenta Crantz) is the principal source of calories among root and tuber crops in tropical countries. Cassava bacterial blight (CBB) caused by Xanthomonas axonopodis pv. manihotis (Xam) is the most prevalent bacterial disease in cassava. Genome and mutagenesis analysis of Xam strains has led to the identification of an effector s...
Published in Tropical Plant Pathology
Species of Pestalotiopsis have been reported to be pathogenic to eucalypt, yet few studies have addressed their real pathogenic potential or even their diagnosis. The objective of this study was to carry out the molecular, micromorphological, physiological and pathogenic characterization of four isolates of Pestalotiopsis sp. found in eucalypt leaf...
Published in Tropical Plant Pathology
Yeasts have been used to manage a large number of plant diseases, but little is known about the mechanisms used by these biocontrol agents. The objectives of the present study were to evaluate the antagonistic effect of yeasts against Rhizoctonia solani and possible mechanisms of action in cowpea plants. Seventy yeast isolates were obtained from le...
