Alternaria Leaf Spot on Mealycup Sage (Salvia farinacea Benth.) Caused by Alternaria alternata (Fr.) Keissler

2002 ◽  
Vol 68 (4) ◽  
pp. 321-325 ◽  
Author(s):  
Hiromitsu NEGISHI ◽  
Kazuo SUYAMA
Keyword(s):  
Alternaria Alternata ◽  
Leaf Spot ◽  
Alternaria Leaf Spot

scholarly journals First Report of Alternaria Leaf Spot of Banana Caused by Alternaria alternata in the United States

Plant Disease ◽  
2013 ◽  
Vol 97 (8) ◽  
pp. 1116-1116 ◽  
Author(s):  
V. Parkunan ◽  
S. Li ◽  
E. G. Fonsah ◽  
P. Ji
Keyword(s):  
United States ◽  
Alternaria Alternata ◽  
Leaf Spot ◽  
Morphological Characteristics ◽  
The United States ◽  
Its Sequencing ◽  
Single Spore ◽  
First Report ◽  
Alternaria Leaf Spot ◽  
Leaf Spots

Research efforts were initiated in 2003 to identify and introduce banana (Musa spp.) cultivars suitable for production in Georgia (1). Selected cultivars have been evaluated since 2009 in Tifton Banana Garden, Tifton, GA, comprising of cold hardy, short cycle, and ornamental types. In spring and summer of 2012, 7 out of 13 cultivars (African Red, Blue Torres Island, Cacambou, Chinese Cavendish, Novaria, Raja Puri, and Veinte Cohol) showed tiny, oval (0.5 to 1.0 mm long and 0.3 to 0.9 mm wide), light to dark brown spots on the adaxial surface of the leaves. Spots were more concentrated along the midrib than the rest of the leaf and occurred on all except the newly emerged leaves. Leaf spots did not expand much in size, but the numbers approximately doubled during the season. Disease incidences on the seven cultivars ranged from 10 to 63% (10% on Blue Torres Island and 63% on Novaria), with an average of 35% when a total of 52 plants were evaluated. Six cultivars including Belle, Ice Cream, Dwarf Namwah, Kandarian, Praying Hands, and Saba did not show any spots. Tissue from infected leaves of the seven cultivars were surface sterilized with 0.5% NaOCl, plated onto potato dextrose agar (PDA) media and incubated at 25°C in the dark for 5 days. The plates were then incubated at room temperature (23 ± 2°C) under a 12-hour photoperiod for 3 days. Grayish black colonies developed from all the samples, which were further identified as Alternaria spp. based on the dark, brown, obclavate to obpyriform catenulate conidia with longitudinal and transverse septa tapering to a prominent beak attached in chains on a simple and short conidiophore (2). Conidia were 23 to 73 μm long and 15 to 35 μm wide, with a beak length of 5 to 10 μm, and had 3 to 6 transverse and 0 to 5 longitudinal septa. Single spore cultures of four isolates from four different cultivars were obtained and genomic DNA was extracted and the internal transcribed spacer (ITS1-5.8S-ITS2) regions of rDNA (562 bp) were amplified and sequenced with primers ITS1 and ITS4. MegaBLAST analysis of the four sequences showed that they were 100% identical to two Alternaria alternata isolates (GQ916545 and GQ169766). ITS sequence of a representative isolate VCT1FT1 from cv. Veinte Cohol was submitted to GenBank (JX985742). Pathogenicity assay was conducted using 1-month-old banana plants (cv. Veinte Cohol) grown in pots under greenhouse conditions (25 to 27°C). Three plants were spray inoculated with the isolate VCT1FT1 (100 ml suspension per plant containing 105 spores per ml) and incubated under 100% humidity for 2 days and then kept in the greenhouse. Three plants sprayed with water were used as a control. Leaf spots identical to those observed in the field were developed in a week on the inoculated plants but not on the non-inoculated control. The fungus was reisolated from the inoculated plants and the identity was confirmed by morphological characteristics and ITS sequencing. To our knowledge, this is the first report of Alternaria leaf spot caused by A. alternata on banana in the United States. Occurrence of the disease on some banana cultivars in Georgia provides useful information to potential producers, and the cultivars that were observed to be resistant to the disease may be more suitable for production. References: (1) E. G. Fonsah et al. J. Food Distrib. Res. 37:2, 2006. (2) E. G. Simmons. Alternaria: An identification manual. CBS Fungal Biodiversity Center, Utrecht, Netherlands, 2007.

scholarly journals Alternaria leaf spot of broccoli caused by Alternaria alternata in Bangladesh

2021 ◽  
Author(s):  
Sayma T. Nira ◽  
Md. Farhad Hossain ◽  
Nur Uddin Mahmud ◽  
Oliul Hassan ◽  
Md. Tofazzal Islam ◽  
...  
Keyword(s):  
Alternaria Alternata ◽  
Leaf Spot ◽  
Maximum Growth ◽  
Pathogenicity Test ◽  
Culture Studies ◽  
Alternaria Leaf Spot ◽  
Cultural Methods ◽  
Molecular Phylogenetic ◽  
Alternaria Sp

  This study aimed to isolate and characterise the pathogen associated with Alternaria leaf spot on broccoli and to evaluate the inhibitory effects of fungicides against it. We isolated and identified the fungal pathogen as Alternaria sp. using morphological and cultural methods. Based on the aligned sequences of the internal transcribed spacer (ITS) and molecular phylogenetic analysis by the neighbour-joining method, the isolates (Ab1 and Ab2) were confirmed as Alternaria alternata. The conidia of the isolates were dark brown, cylindrical, obclavate to muriform. The conidiophores were olivaceous brown, septate, and branched. The conidial morphology of the isolates ranged from 52.4–92.4 × 10–20 μm with 2–6 transverse and 0–3 longitudinal septa. Both isolates yielded positive results in the pathogenicity test on broccoli leaves by developing brown and circular spots with concentric rings on the leaves surrounded by yellow halos. The culture studies revealed that the maximum growth of the pathogen was obtained at 30 °C and pH 6.0. Tilt 250 WC showed the highest potential in suppressing the mycelial growth of the A. alternata in vitro at a concentration as low as 50 µg/mL. The results from this study contributed to the positive identification of the pathogen and characterised A. alternata as a destructive pathogen of broccoli which may be successfully controlled by the fungicide Tilt.  

First report of Alternaria leaf spot caused by Alternaria alternata (Fries.) Kiessler on Sonchus oleraceus L. and Convolvulus arvensis L. in Algeria

2019 ◽  
Vol 167 (6) ◽  
pp. 321-325
Author(s):  
Nesma Abdessemed ◽  
Ali Kerroum ◽  
Youssef Anis Bahet ◽  
Nacèra Talbi ◽  
Nadjia Zermane
Keyword(s):  
Alternaria Alternata ◽  
Leaf Spot ◽  
Convolvulus Arvensis ◽  
First Report ◽  
Sonchus Oleraceus ◽  
Alternaria Leaf Spot

Alternaria leaf spot of basil caused by Alternaria alternata in Japan

2009 ◽  
Vol 75 (2) ◽  
pp. 160-162 ◽  
Author(s):  
Satoshi Taba ◽  
Ayano Takara ◽  
Kanami Nasu ◽  
Nao Miyahira ◽  
Tetsuya Takushi ◽  
...  
Keyword(s):  
Alternaria Alternata ◽  
Leaf Spot ◽  
Alternaria Leaf Spot

scholarly journals First Report of Alternaria Leaf Spot Caused by Alternaria alternata on Spinach in Poland

Plant Disease ◽  
2015 ◽  
Vol 99 (5) ◽  
pp. 729-729 ◽  
Author(s):  
A. Czajka ◽  
A. Czubatka ◽  
J. Sobolewski ◽  
J. Robak
Keyword(s):  
Alternaria Alternata ◽  
Leaf Spot ◽  
First Report ◽  
Alternaria Leaf Spot

scholarly journals Effects of Physical Parameters on Growth of Alternaria alternata causing Alternaria Leaf Spot of Lehsua

2020 ◽  
Vol 8 (2) ◽  
pp. 515-519
Author(s):  
Sushila Choudhary ◽  
RP Ghasolia ◽  
Manisha Shivran ◽  
Ramniwas Yadav
Keyword(s):  
Alternaria Alternata ◽  
Leaf Spot ◽  
Physical Parameters ◽  
Alternaria Leaf Spot

scholarly journals First Report of Alternaria Leaf Spot Caused by Alternaria alternata on Idesia polycarpa in China

Plant Disease ◽  
2015 ◽  
Vol 99 (8) ◽  
pp. 1177
Author(s):  
L. Sun ◽  
Y. Hao ◽  
Y. M. Wu ◽  
L. Wang ◽  
Y. C. Liang
Keyword(s):  
Alternaria Alternata ◽  
Leaf Spot ◽  
First Report ◽  
Alternaria Leaf Spot
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