ABSTRACT
Abstract A new species of gall midge that induces stem galls on Aeschynomene denticulata (Fabaceae) is described based on material collected in Pantanal (Mato Grosso do Sul, Brazil). This species is unique among the Brazilian congeners in having spatula with three convex teeth, cruciate, with defined anterolateral extensions, four lateral papillae on each side of the spatula, and three pairs of terminal papillae (larva), four-segmented palpi (adult), 17 flagellomeres (female), ovipositor about 11 times length of seventh tergite.
Resumo Uma nova espécie de Cecidomyiidae que induz galhas caulinares em Aeschynomene denticulata (Fabaceae) é descrita com base em material coletado no Pantanal (Mato Grosso do Sul, Brasil). Esta espécie é única entre as congenéricas brasileiras por possuir espátula com três dentes convexos, com extensões anterolaterais cruzadas e bem definidas, quatro papilas laterais de cada lado da espátula e três pares papilas terminais (larva), palpos com quatro segmentos (adulto), 17 flagelômeres (fêmeas), ovipositor cerca de 11 vezes mais longo que o sétimo tergito.
Subject(s)
Animals , Female , Diptera/classification , Fabaceae , Oviposition/physiology , Plant Diseases/etiology , Brazil , Chironomidae , Diptera/physiology , Host-Parasite Interactions , Larva/classification , Larva/physiologyABSTRACT
Aims: To study storage rots in yam varieties cultivated in South East Nigeria and to determine under conditions of experimental storage, the influence of fungal rot on their post harvest storage losses. Place and Duration of Study: Laboratories, Department of Applied Microbiology & Brewing, Nnamdi Azikiwe University, Awka, Nigeria between January 2012 and July 2013. Methodology: Five yam varieties; Dioscorea dumentorum, two varieties each of D. alata and D. rotundata, obtained immediately after harvest were stored in an experimental barn (30ºC and 95% RH) and examined at intervals for storage rots. Fungal causative agents of rots were isolated and identified using the partial ITS rDNA sequencing analysis and a BLAST search using the GenBank sequence database. Post harvest storage losses in terms of weight loss and reduction of shelf life among the varieties were determined. Results: All varieties of yams studied suffered fungal rots, predominantly, dry rots during storage. Seven distinct fungal isolates, which caused these rots, were fully characterized. The species were Aspergillus tamari, Fusarium solani, Lasiodiplodia theobromae, Aspergillus niger, Mucor circinelloides, Aspergillus flavus and Aspergillus sp. In all the yams, storage rots reduced shelf life and aggravated weight loss. Post harvest storage losses varied among the different varieties of yams. Conclusion: The varieties of yams studied suffer rots from various fungi, which are similar to those reported in other parts of the world. Severity of post harvest losses resulting from fungal rots varies among different varieties of yams. This should be taken into consideration in the development of storage techniques.
Subject(s)
Databases, Nucleic Acid , Dioscorea/classification , Dioscorea/metabolism , Dioscorea/microbiology , Food Contamination/prevention & control , Food Microbiology , Food Preservation/methods , Food Storage , Fungi , Nigeria , Plant Diseases/etiology , Sequence Analysis, DNAABSTRACT
Spontaneous plants of Ipomoea acuminata ("morning glory") exhibiting white rust pustules were found in a field crop area of Planaltina, DF, in the fall season of 2010 and the disease causal agent was identified as Albugo ipomoea-panduratae (Oomycota). No reports of the association between A. ipomoea-panduratae and I. acuminata were known in Brazil previously to 2010. A reference specimen was deposited at the University of Brasilia Mycological Reference Collection.
Subject(s)
Plant Diseases/etiology , Iron Bacteria , Ipomoea/growth & development , Ipomoea/microbiology , Environmental Microbiology , Methods , MethodsABSTRACT
Myrothecium roridum and M. verrucaria are two plant pathogenic species causing foliar spots in a large number of cultivated plants. This paper aims to study the causal agents of foliar spots in vegetable crops (sweet pepper, tomato and cucumber), ornamental plants (Spathiphyllum wallisii, Solidago canadensis, Anthurium andreanum, Dieffenbachia amoena) and a solanaceous weed plant (Nicandra physaloides). Most of the isolates were identified as M. roridum; only the isolate 'Myr-02' from S. canadensis was identified as M. verrucaria. All the isolates were pathogenic to their original plant hosts and also to some other plants. Some fungicides were tested in vitro against an isolate of M. roridum and the mycelial growth recorded after seven days. Fungicides with quartenary ammonium, tebuconazole and copper were highly effective in inhibiting the mycelial growth of M. roridum. This paper confirms the first record of M. roridum causing leaf spots in sweet pepper, tomato, Spathiphyllum, Anthurium, Dieffenbachia and N. physaloides in Brazil. We also report M. roridum as causal agent of cucumber fruit rot and M. verrucaria as a pathogen of tango plants.
Subject(s)
Plant Diseases/etiology , Plant Structures/genetics , Fungicides, Industrial , In Vitro Techniques , Mycelium/growth & development , Mycelium/isolation & purification , Plant Leaves , Plants, Edible , Solidago/growth & development , Methods , Methods , Vegetables , VirulenceABSTRACT
Plants of Viola cornuta displaying typical virus symptoms were observed during spring 2003 in a plant nursery in Córdoba, central Argentina. Electron microscopic examinations of symptomatic leaf samples revealed the presence of isometric virus-like particles about 30 nm in diameter. Subsequent serological analysis allowed the identification of the pathogen as a subgroup 1 strain of Cucumber mosaic virus (CMV). These results were confirmed by antigen capture - reverse transcription - polymerase chain reaction with specific CMV primers, and digestion with a restriction enzyme. This is the first report of CMV infecting V cornuta in Argentina
Subject(s)
Cucumovirus , Plant Diseases/etiology , Plant Diseases/virology , Serology/methodsABSTRACT
A granulovirus (GV) was isolated from the field-bean pod borer, Adisura atkinsoni. Electron microscopic observation showed capsule or granular shaped occlusion bodies. The virus was highly virulent against second instar larvae when tested at 1 x 10(6) occlusions/larva through food surface (pod/seed) contamination technique. The incubation period ranged from 6-10 days in the case of second instar larvae. In contrast to green coloured healthy larvae. GV infected A. atkinsoni became brownish/pale white in colour mostly due to accumulation of large number of occlusion bodies. Study on the cross infectivity of A. atkinsoni GV to gram caterpillar, Helicoverpa armigera revealed the high susceptibility of H. armigera to A. atkinsoni GV, thereby widening the scope of controlling both the species on the same cropping system. This is the first record of GV from A. atkinsoni from India.
Subject(s)
Animals , Color , Food Contamination , Granulovirus/pathogenicity , Inclusion Bodies , India , Plant Diseases/etiology , Viral Interference , VirulenceABSTRACT
When nucleopolyhedro virus of A. atkinsoni was applied at 250 LE/ha, there was no significant difference between the viruses treated and control plots with regard to the total number of live larvae feeding outside the pod. However, due to changes in behaviour in NPV infected A. atkinsoni by way of coming out of the pod, there was a significant difference when counts were taken with regard to total number of larvae found feeding inside the pod. Both endosulfan at (0.07%) and virus (125 LE/ha) in combination with endosulfan (0.035%) significantly reduced the larval population of A. atkinsoni and Sphaenarches anisodactylus. There was no significant difference between the virus and control plots with regard to percentage of pod damage. However, when the yield was assessed based on the seed weight, there was significant difference.
Subject(s)
Animals , Endosulfan/pharmacology , Fabaceae/drug effects , Hydrocarbons, Chlorinated , Insect Control , Insecticides/pharmacology , Larva/drug effects , Moths/drug effects , Plant Diseases/etiologyABSTRACT
A rust disease on the Brazilian orchid Pleurothallis mentigera was found in Mata do Jambreiro, a tropical forest in Minas Gerais State, caused by a fungus identified as Sphenospora kevorkianii Linder is described. P. mentigera Kraenzl. is added to S. kevorkianii host range.
Subject(s)
Plant Diseases/etiology , Fungi , In Vitro Techniques , BiotechnologyABSTRACT
La incidencia de infecciones humanas por especies de Fusarium se ha incrementado en la medicina contemporánea fundamentalmente con el advenimiento de la inmunodepresión. El reconocimiento de estas especies involucradas en tales procesos, como sabemos, es dificultosa, por eso en este trabajo resumimos los aspectos más característicos a tener en cuenta y los principales criterios que pueden ser usados para la identificación de las especies responsables. Las principales características que se describen son: macromorfología de la colonia, por el anverso y el reverso. Micromorfología de las colonias: conidióforos, conidias macroconidias, mesoconidias, microconidias, clamidoconidias. También se incluye una clave de identificación de las especies de Fusarium más frecuentemente aisladas de lesiones humanas
Subject(s)
Humans , Fusarium/isolation & purification , Diagnosis, Differential , Fusarium/classification , Fusarium/pathogenicity , Mycoses/complications , Plant Diseases/etiologyABSTRACT
Foi conduzido um estudo sobre ocorrência de sorogrupos de Bradyrhizobium japonicum em nódulos de soja cultivar Doko. O experimento foi conduzido em vasos com solos coletados em vários locais dos Cerrados, sendo a soja semeada sem inoculaçäo O sorogrupo 566 foi o dominante em 13, dentre 20 areas de cultivo de soja, que, aparentemente, nunca haviam sido inoculadas com estirpes desse serogrupo. Resultados semelhantes foram encontrados na área experimental do CPAC, onde essa estirpe nunca havia sido inoculada, mas que apresentou plantas de soja com até 94 por cento dos nódulos ocupados por essa estirpe. Em outro estudo, objetivou-se acompanhar as flutuaçöes sazonais da ocorrência dos serogrupos na soja em uma área no campo, através de amostragens mensais de solo que eram distribuidos em vasos e semeados com soja näo inoculada. Apesar de ocorrerem flutuaçöes significativas nas percentagens de ocorrência dos serogrupos, näo houve alteraçöes na ordem de dominância das estirpes durante os meses em que foi conduzido o experimento