scholarly journals Outbreaks of Alternaria Brown Spot of Citrus in Brazil and Argentina

Plant Disease ◽  
2003 ◽  
Vol 87 (6) ◽  
pp. 750-750 ◽  
Author(s):  
N. A. R. Peres ◽  
J. P. Agostini ◽  
L. W. Timmer
Keyword(s):  
Morphological Characteristics ◽  
Severe Infection ◽  
Sao Paulo ◽  
Brown Spot ◽  
Control Treatment ◽  
Citrus Reticulata ◽  
Conidial Suspension ◽  
São Paulo ◽  
Surface Sterilization ◽  
Alternaria Brown Spot

Alternaria alternata (Fr.) Keissler causes lesions on leaves, twigs, and fruit and reduces yield and fruit quality of many tangerines (Citrus reticulata) and their hybrids (2). Severe outbreaks of Alternaria brown spot were observed on ‘Murcott’ tangor (Citrus reticulata × Citrus sinensis) trees in southern São Paulo, southern Minas Gerais states in Brazil, and in Misiones and Corrientes provinces in Argentina. A single diseased ‘Fortune’ tangerine tree was observed in a grove in Misiones. On young leaves, brown-to-black lesions often expanded to cover large parts of the leaf, causing abscission of young shoots and dieback of twigs. Lesions were often surrounded by yellow halos. On fruit, dark specks from 0.2 to 0.5 cm were observed, and severe infection caused premature fruit abscission. Isolations were made on potato dextrose agar (PDA) after surface sterilization of leaf and fruit tissues in 1.5% sodium hypochlorite for 1 min. Plates were incubated at 27°C in the dark for 1 week. Isolated colonies were olive brown to black, and the fungus was stimulated to form conidia by scraping the surface of the mycelium. The pathogen was a typical small-spored Alternaria species, and the morphological characteristics of the conidia and conidiophores fit the description of A. alternata. Inoculation of three detached young shoots of ‘Murcott’ with a conidial suspension (105 conidia per ml) confirmed pathogenicity of three isolates obtained from widely separated groves in southern and eastern São Paulo State in Brazil and one from Misiones Province in Argentina. A control treatment with an equal number of shoots was sprayed with distilled water only. After 48 h, all isolates caused dark lesions on the leaves, characteristic of the disease. Symptoms were observed on inoculated, but not on control shoots. Koch's postulates were satisfied by reisolation of the fungus from symptomatic tissue in all cases. Although Alternaria brown spot was reported previously in neighboring Rio de Janeiro, Brazil on ‘Dancy’ and ‘Ponkan’ tangerines (1), serious disease problems now occur on ‘Murcott’, an important commercial variety in the major production area in Brazil. To our knowledge, this is the first report of Alternaria brown spot in Argentina. References: (1) A. de Goes et al. Fitopatologia Brasileira 26(Suppl.):386, 2001. (2) L. W. Timmer et al. Pages 19–21 in: Compendium of Citrus Diseases. 2nd ed. L. W. Timmer, S. M. Garnsey, and J. H. Graham, eds. The American Phytopathological Society, St. Paul, MN, 2000.

scholarly journals First Report of Alternaria Brown Spot of Citrus Caused by Alternaria alternata in Yunnan Province, China

Plant Disease ◽  
2010 ◽  
Vol 94 (3) ◽  
pp. 375-375 ◽  
Author(s):  
X. F. Wang ◽  
Z. A. Li ◽  
K. Z. Tang ◽  
C. Y. Zhou ◽  
L. Yi
Keyword(s):  
Alternaria Alternata ◽  
Yunnan Province ◽  
Morphological Characteristics ◽  
Control Measures ◽  
Brown Spot ◽  
Control Treatment ◽  
Infected Leaf ◽  
Conidial Suspension ◽  
First Report ◽  
Alternaria Brown Spot

Brown spot of citrus is considered a major problem on the fruit of many citrus cultivars grown for fresh markets including tangerines (Citrus reticulata) and their hybrids. It causes lesions on leaves, stems, and fruit and reduces yield and fruit quality (2). In 2003 in southern Wenshan Municipality, Yunnan Province in China, sporadic occurrence of Alternaria brown spot was observed on Tangfang mandarin, a local citrus cultivar identified preliminarily as a kind of mandarin hybrid. From 2006 to 2008, nearly 80% of local orchards were infected with the disease. Fruit symptoms typical of Alternaria brown spot ranging from light brown, slightly depressed spots to circular and dark brown areas were observed. Leaves showed small, brown, circular spots and irregular blighted areas with characteristic yellow halos. Tissues from the margin of fruit spots or infected leaf parts of eight different trees were surface sterilized in 1.5% sodium hypochlorite for 1 min, plated on potato dextrose agar (PDA), and then incubated at 27°C in the dark for 1 week. Dark brown mycelia and pigmented septate conidia with lengths of 10 to 35 μm and widths of 5 to 13 μm were produced. On the basis of conidial morphological characteristics, the pathogen was identified as Alternaria alternata (Fr.:Fr.) Keissl (1). Detached young healthy leaves of ‘Minneola’ tangelo (C. reticulata × C. paradisi) were sprayed with a conidial suspension of 105 conidia per ml and incubated in a moist chamber at 27°C. A control treatment with an equal number of leaves was sprayed with distilled water only. After 48 h, seven of these isolates caused necrotic lesions on detached leaves, characteristic of the disease, whereas there were no symptoms on leaves of the water control. Pure cultures were recovered on PDA from symptomatic tissues and the morphological characteristics of the conidia closely fit the description of A. alternata, confirming Koch's postulates. Currently, the distribution of Alternaria brown spot of citrus is confined to southern Wenshan Municipality in Yunnan Province where it is a serious disease problem on the most important commercial cultivar in this region. The identification of the pathogen now allows for appropriate field management and control measures. To our knowledge, this is the first report of Alternaria brown spot of citrus in China. References: (1) Z. Solel. Plant Pathol. 40:145, 1991. (2) J. O. Whiteside. Plant Dis. Rep. 60:326, 1976.

scholarly journals First Report on Quinone Outside Inhibitor Resistance of Alternaria alternata Causing Alternaria Brown Spot in Tangerines in São Paulo, Brazil

2019 ◽  
Vol 20 (2) ◽  
pp. 94-94 ◽  
Author(s):  
Gabriel M. Chitolina ◽  
Geraldo J. Silva-Junior ◽  
Eduardo Feichtenberger ◽  
Rosana G. Pereira ◽  
Lilian Amorim
Keyword(s):  
Alternaria Alternata ◽  
Sao Paulo ◽  
Field Resistance ◽  
Brown Spot ◽  
São Paulo ◽  
Qoi Fungicides ◽  
First Report ◽  
Quinone Outside Inhibitor ◽  
Alternaria Brown Spot ◽  
Inhibitor Resistance

Field resistance to quinone outside inhibitor (QoI) fungicides in Alternaria alternata causing Alternaria brown spot of mandarins was reported by growers in Brazil in 2017. Conidial germination tests were performed, and isolates showed effective concentration to inhibit 50% of conidia germination (EC50) to be over 100 ppm. This is the first report of QoI resistance in A. alternata causing Alternaria brown spot in the state of São Paulo, Brazil.

scholarly journals Veronica sibirica Leaf Spots Caused by Phacellium veronicae, a New Disease in China

Plant Disease ◽  
2013 ◽  
Vol 97 (12) ◽  
pp. 1662-1662 ◽  
Author(s):  
Q. R. Bai ◽  
S. Han ◽  
Y. Y. Xie ◽  
J. Gao ◽  
Y. Li
Keyword(s):  
Morphological Characteristics ◽  
Its Region ◽  
Control Treatment ◽  
Perennial Herb ◽  
Conidial Suspension ◽  
New Disease ◽  
Medical College ◽  
Leaf Spots ◽  
Plastic Bags ◽  
Insect Bites

Veronica sibirica (Veronicastrum sibiricum) is an erect perennial herb, an ornamental, and a traditional Chinese medicine plant distributed mostly in northeastern, northern, and northwestern China. It has dehumidifying and detoxifying properties, and is mainly used for the treatment of cold, sore throat, mumps, rheumatism, and insect bites (4). In June 2008 through 2012, leaf spots of V. sibirica were observed in the Medicinal Herb Garden of Jilin Agricultural University (43°48′N, 125°23′E) and the medicinal plantations of Antu County (43°6′N, 128°53′E), Jilin Province. Leaf spots were amphigenous, subcircular, angular-irregular, brown, and 1 to 10 mm in diameter; they occasionally merged into a larger spot with an indefinite margin or with a pale center and dark border. Pale conidiomata were hypophyllous and scattered on the spots. The conidiophores were 100 to 400 μm high and clustered together to form synnemata 20 to 50 μm in diameter, which splayed out apically and formed loose to dense capitula. Conidiophores occasionally emerged through the stomata individually and produced conidia on the surface of the infected leaves. The conidiogenous cell terminal was geniculate-sinuous with somewhat thickened and darkened conidial scars. Conidia were solitary or catenulate, ellipsoid-ovoid or subcylindric-fusiform, hyaline and spinulose, 4.01 to 7.18 × 11.16 to 20.62 μm with obtuse to somewhat attenuated ends, and slightly thickened, darkened hila. Six isolates were obtained from necrotic tissue of leaf spots and cultured on potato dextrose agar at 25°C. After incubation for 14 days, colony surfaces were white to pinkish. The colony diameter increased by 12 mm after 21 days' incubation. Hyphae were hyaline, septate, and branched. Conidiophores grew individually or fascicularly. The symptoms and morphological characteristics were consistent with previous descriptions (1,2), and the fungus was identified as Phacellium veronicae (Pass.) (U. Braun 1990). The internal transcribed spacer (ITS) region of the nuclear rDNA was amplified using primers ITS4/ITS5 (3). The ITS was identical among all six isolates (HE995799) and 98% identical to that of P. veronicae (JQ920427, HQ690097). Pathogenicity was confirmed by spraying five 1-year-old V. sibirica seedlings with a conidial suspension (106 conidia/ml) of each isolate and five seedlings with sterile water as a control treatment. Plants were grown in the greenhouse at 20 to 25°C and were covered with plastic bags to maintain humidity on the foliage for 72 h. After 15 days, the same symptoms appeared on the leaves as described earlier for the field-grown plants; the control plants remained healthy. The same fungus was reisolated from the leaf spots of inoculated plants. Currently, the economic importance of this disease is limited, but it may become a more significant problem, as the cultivated area of V. sibirica is increasing. To our knowledge, although P. veronicae was recorded on the other species of Veronica (V. austriaca, V. chamaedrys, V. grandis, V. longifolia, V. paniculata, and V. spicata ssp. incana) in Europe (Germany, Denmark, Ireland, Romania) and V. wormskjoldii in North America (Canada) (1), this is the first report of V. sibirica leaf spots caused by P. veronicae in the world, and it is a new disease in China. References: (1) U. Braun. A monograph of Cercosporella, Ramularia and allied genera (phytopathogenic Hyphomycetes) 2, IHW-Verlag, Germany, 1998. (2) U. Braun. Nova Hedwigia 50:499, 1990. (3) D. E. L. Cooke et al. Mycol. Res. 101:667, 1997. (4) Jiangsu New Medical College. Dictionary of Chinese Materia Medica. Shanghai: Shanghai Scientific and Technical Publishers, China, 1977.

scholarly journals Density and diversity of filamentous fungi in the water and sediment of Araçá bay in São Sebastião, São Paulo, Brazil

2018 ◽  
Vol 18 (1) ◽  
Author(s):  
Sonia Assami Doi ◽  
Aline Bartelochi Pinto ◽  
Maria Carolina Canali ◽  
Daiane Raquel Polezel ◽  
Roberta Alves Merguizo Chinellato ◽  
...  
Keyword(s):  
Filamentous Fungi ◽  
Chemical Properties ◽  
Morphological Characteristics ◽  
Sao Paulo ◽  
Northern Coast ◽  
São Paulo ◽  
Mangrove Swamp ◽  
Sediment Samples ◽  
Water And Sediment ◽  
Pharmaceutical Industries

Abstract Araçá Bay, located in the city of São Sebastião, São Paulo, Brazil, is a protected area of substantial complexity. It represents the last remaining mangrove swamp preserve between the cities of Bertioga and Ubatuba on the northern coast of São Paulo State. This mangrove swamp has specific physical and chemical properties, and it shelters a wide variety of life, including fungi. These microorganisms are present in a variety of species with different morphophysiological features, and they have the ability to produce enzymes of biotechnological importance. The goal of this study was to quantify, isolate, and identify filamentous fungi in water and sediment samples from the Araçá Bay mangrove swamp in São Sebastião. Two samplings were performed in the summer and two were performed in the winter. The samples were collected from intertidal zones, and dissolved oxygen (DO), temperature, salinity, and pH were measured in situ. The spread plate technique was used to inoculate the samples collected on plates with a potato dextrose agar (PDA) medium. A total of 208 colonies (68 from water samples and 140 from sediment samples) were isolated, and they were identified based on their morphological characteristics. Filamentous fungus density was higher in the sediment than in the water, and the samplings performed in the winter revealed a higher density than those performed in the summer. Though some of the environmental parameters were not ideal for fungal development, a high quantity of growth was nevertheless observed. When the isolated colonies were analyzed, the greatest diversity and species richness were found in the summer samples. The genera identified in all of the samples were Aspergillus, Penicillium, Cladosporium, and Fusarium. The pathogenic species found from these genera were Aspergillus fumigatus, A. terreus, Penicillium citrinum, and P. chrysogenum. These species are also able to produce enzymes that offer a variety of applications. The fungal community described herein represents the diversity found in this mangrove swamp during the period studied. Many of the fungus species found are pathogenic and may be useful due to their ability to produce specific enzymes applicable in the biotechnological and pharmaceutical industries.

scholarly journals Morphological divergence of seedlings Calophyllum brasiliense cambes collected in São Paulo and Tocantins

2021 ◽  
Author(s):  
Ildon Rodrigues Nascimento ◽  
Cândida Pereira da Silva ◽  
Irais Dolores Pascual-Reyes ◽  
Aline Torquato Tavares ◽  
Edilson Nonato da Silva ◽  
...  
Keyword(s):  
Root Length ◽  
Quality Index ◽  
Morphological Characteristics ◽  
Dry Mass ◽  
Sao Paulo ◽  
The State ◽  
Morphological Divergence ◽  
São Paulo ◽  
Calophyllum Brasiliense ◽  
Number Of Leaves

Objective: The objective was to quantify the morphological diversity of Calophyllum brasiliense Cambes from four municipalities of the State of Tocantins employing morphological characteristics, to strengthen information on conservation and future breeding of the species. Methodology: Seeds were collected from four municipalities in the State of Tocantins and one in the State of São Paulo. The following were evaluated: plant height, stem diameter, root length, number of leaves, leaf area, root dry mass, shoot dry mass, total dry mass, and Dickson´s quality index. The data were subjected to univariate analysis of variance, Tocher grouping method, and UPGMA, obtaining a dendrogram through the generalized Mahalanobis distance. Results: The results showed a statistical difference of 1 and 5% probability. Dueré stood out in stem diameter(5.52 mm), Sandolandia in height (34.84 cm) and root length (42.13 cm). Formoso stood out in the number of leaves (34 leaves). Lagoa da Confusão in leaf area (856.28 cm 2 ) and São Paulo in root dry mass (16.20 g), shoot dry mass (12.38 g), total dry mass (16.20 g), and Dickson´s quality index (1.57). Implications: Variations in morphological characteristics can be used as a tool for genetic studies of guanandi progeny accordingto their similarity and/or differences. Conclusions: The morphological divergence evidenced that among the five studied areas it is possible to direct the collection of seeds to subsidize conservation strategies and future breeding of the species.

First report of Alternaria brown spot of Citrus reticulata cv. ‘Kinnow’ caused by Alternaria arborescens in Pakistan

2019 ◽  
Vol 102 (1) ◽  
pp. 235-236
Author(s):  
Anam Moosa ◽  
Ayaz Farzand ◽  
Muhammad Fahim Abbas ◽  
Shahbaz Talib Sahi ◽  
Sajid Aleem Khan ◽  
...  
Keyword(s):  
Brown Spot ◽  
Citrus Reticulata ◽  
First Report ◽  
Alternaria Arborescens ◽  
Alternaria Brown Spot

scholarly journals A new species of Lizerius Blanchard (Hemiptera: Drepanosiphidae) from Brazil

2019 ◽  
Vol 109 ◽  
Author(s):  
Suzan B. Z. Cunha ◽  
Carlos R. Sousa-Silva
Keyword(s):  
New Species ◽  
Morphological Characteristics ◽  
Aphid Species ◽  
Sao Paulo ◽  
Persea Americana ◽  
São Paulo ◽  
A New Species

ABSTRACT In this study a new aphid species of the genus Lizerius Blanchard, 1923 (Hemiptera: Drepanosiphidae) is described. Samplings were carried out in the municipalities of Porto Ferreira and Pedregulho, state of São Paulo, Brazil, over plants of Persea americana Mill, 1768 and Terminalia brasiliensis Spreng, 1825. Morphological characteristics of apterous and alate are described and represented by drawings.

Supplementary data of Henneguya leporinicola (Myxozoa, Myxosporea) a parasite of Leporinus macrocephalus from fish farms in the state of São Paulo, Brazil

2015 ◽  
Vol 60 (3) ◽  
Author(s):  
Kassia Roberta Hygino Capodifoglio ◽  
Edson Aparecido Adriano ◽  
Marcia Ramos Monteiro da Silva ◽  
Antônio Augusto Mendes Maia
Keyword(s):  
18S Rdna ◽  
Gill Filament ◽  
Morphological Characteristics ◽  
Sao Paulo ◽  
The State ◽  
Rdna Sequence ◽  
São Paulo ◽  
Fish Farms ◽  
Basal Branch ◽  
18S Rdna Sequence

AbstractHenneguya leporinicola is a parasite of the gill filament of Leporinus macrocephalus, a characiform fish belonging to the Anostomidae family, which is of major economic importance. Despite the damage it causes in fish, little is known about this parasite. Therefore, a study was undertaken with fourteen specimens of L. macrocephalus taken from fish farms in the state of Sao Paulo. The fish were collected and examined searching for lesions and/or myxosporean plasmodia. One of the specimens (7.14%) contained white elongated plasmodia in the gill filament. The mature spores had elongated bodies with polar capsules of equal size and a caudal length greater than body length. Morphological characteristics identified the parasite as H. leporinicola. Molecular analysis of the 18S rDNA sequence resulted in a 1954 bp, demonstrating significant genetic differences with previously described species of Henneguya/Myxobolus. Phylogenetic analysis comparing the 18S rDNA sequence of H. leporinicola with other species, previously described in South America, and the 20 closest species as indicated by BLASTn Max Score showed H. leporinicola as a basal branch of a subclade composed by Henneguya spp. parasite of characiform hosts.

scholarly journals PRODUCTIVE AND MORPH-PHYSIOLOGICAL PARAMETERS OF PEANUT CULTIVARS

2021 ◽  
Vol 5 (1) ◽  
pp. 1-8
Author(s):  
Lucas Aparecido Manzani Lisboa ◽  
Matheus Luis Oliveira Cunha ◽  
Fernando Takayuki Nakayama ◽  
Ignácio José de Godoy ◽  
Rodrigo Aparecido Vitorino ◽  
...  
Keyword(s):  
Experimental Design ◽  
Genetic Variability ◽  
Morphological Characteristics ◽  
Sao Paulo ◽  
Physiological Parameters ◽  
Physiological Characteristics ◽  
São Paulo ◽  
Productive Potential ◽  
Peanut Cultivars

Studies of adaptability, agronomic characterization and productive potential of peanuts, including information on morphophysiological characteristics, make it a strategy for choosing the best cultivar. In view of the above, the objective of this work was to verify the physiological characteristics and productivity of different peanut cultivars. In January of 2019 an experiment was installed in the Paulista Agribusiness Technology Agency, Regional Paulista Regional Camp, located in the municipality of Adamantina, state of São Paulo. The experimental design was in randomized blocks with six treatments, that is, peanut cultivars: Tatu, Semper Verde, OL3, OL5, 503 and 505 and with six replications totaling 36 plots, where each plot was composed of three plants. The Tatu cultivar showed low values ​​of morphological characteristics and productivity compared to other cultivars. The cultivars OL3, OL5, 503 and 505 showed higher averages of productivity. Great genetic variability was observed among the cultivars evaluated in this research due to the results obtained in the physiological and productivity variables.

scholarly journals Caracterização pós-colheita de variedades de tangerina com potencial de produção e comercialização no Estado de Goiás

Agrarian ◽  
2018 ◽  
Vol 11 (42) ◽  
pp. 319-323
Author(s):  
Rafaela Israel Alcântara ◽  
Yanuzi Camilo ◽  
Wandir Netto Rodrigues ◽  
Toshio Ogata
Keyword(s):  
Sao Paulo ◽  
Citrus Reticulata ◽  
São Paulo

A citricultura em Goiás vem se sobressaindo no cenário brasileiro, visando competir com o mercado de São Paulo. No entanto, as variedades cultivadas comercialmente no país e em Goiás são consideradas limitadas, visto o amplo mercado que esse tipo de fruta pode atingir. Assim, objetivou-se caracterizar física e quimicamente, 3 variedades de tangerinas (Citrus reticulata), produzidas em Goiás, visando qualidade para consumo in natura e/ou processamento, de forma a competir no mercado brasileiro. As 3 variedades analisadas foram: Ponkan, Kiomi tangor e Dekopon. Foram coletados 30 frutos de cada variedade, obtendo-se um delineamento inteiramente casualizado com 3 variedades e 30 repetições. Os frutos foram avaliados quanto ao peso, altura e diâmetro com casca e sem casca, número de sementes por fruto e rendimento de suco. Quimicamente foram analisadas o teor de sólidos solúveis totais (ºBrix), acidez titulável, e ratio (SST/acidez). Os dados foram submetidos à ANOVA e comparadas pelo teste Tukey a 5%. A dekopon apresentou o maior tamanho e peso de frutos, sendo que a ponkan a que apresentou os menores frutos. Não houve diferença significativa entre a dekopon e a Kiomi tangor para o rendimento de suco. A Dekopon se destacou pelo fato de não possuir sementes, o que seria uma preferência para consumo in natura e processamento. Esta também se sobressaiu quanto ao teor de sólidos solúveis totais, podendo ter maior comercialização in natura. As variedades analisadas apresentaram potencial para competir no mercado, sendo a Kiomi tangor indicada para indústria, e as demais para consumo in natura. 

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