Rhizopus oryzae Associated with Melanagromyza splendida and Stem Disease of Sunflowers (Helianthus annuus) in California

2015 ◽  
Vol 16 (1) ◽  
pp. 39-42 ◽  
Author(s):  
Febina M. Mathew ◽  
Jarrad R. Prasifka ◽  
Stephen D. Gaimari ◽  
Li Shi ◽  
Samuel G. Markell ◽  
...  
Keyword(s):  
Helianthus Annuus ◽  
Seed Production ◽  
Geographic Distribution ◽  
Sunflower Seed ◽  
Rhizopus Oryzae ◽  
Causal Agent ◽  
Parental Line ◽  
Disease Symptoms ◽  
Stem Infection ◽  
Head Rot

In September 2012, a female parental line in a Yolo Co., California, sunflower seed-production field began displaying external stem symptoms that could not be attributed to any known disease. Symptoms appeared to be associated with tunneling caused by an unidentified insect. Stems were collected, and Rhizopus oryzae (causal agent of Rhizopus head rot) and a minute fly, Melanagromyza splendida, were identified as the causal agent and associated insect, respectively. Further, R. oryzae was isolated from intact fly puparia. All commercial hybrids evaluated in the greenhouse were susceptible to stem infection by R. oryzae isolates. Yield implications and geographic distribution of this novel stem disease are unknown. This is the first report of R. oryzae causing stem disease in sunflowers, and of its association with M. splendida. Accepted for publication 10 January 2015. Published 25 March 2015.

RELATION OF INFESTATION WITH SUNFLOWER MOTH HOMOEOSOMA ELECTELLUM LARVAE TO THE INCIDENCE OF RHIZOPUS ROT IN SUNFLOWER SEED HEADS

1979 ◽  
Vol 59 (3) ◽  
pp. 797-801 ◽  
Author(s):  
J. M. KLISIEWICZ
Keyword(s):  
Helianthus Annuus ◽  
Sunflower Seed ◽  
Rhizopus Oryzae ◽  
Helianthus Annuus L ◽  
Head Rot ◽  
Sunflower Moth ◽  
Homoeosoma Electellum ◽  
Rhizopus Rot

Larvae of the moth Homoeosoma electellum (Hulst.) were found consistently in sunflower (Helianthus annuus L.) seed heads affected with Rhizopus rot in California. Both Rhizopus rot and larvae were found in 88% of the rotted heads examined and only Rhizopus rot was evident in 12% of the heads. Head rot developed in 55–100% of the sunflower heads artificially inoculated in the field with both Rhizopus oryzae Went & Brinsen-Geerlings and H. ellectellum larvae and in 5–20% of the heads inoculated only with Rhizopus. Rot did not occur in heads in which only larvae were present. Larvae enhanced infection of the receptacle by Rhizopus through feeding injury. Ingested spores that are viable after passage through the gut of a larva can be spread by larvae into the inner tissues of the sunflower receptacle.

Rhizopus oryzae as a causal agent of a head rot of sunflowers in Queensland

1977 ◽  
Vol 17 (86) ◽  
pp. 495 ◽  
Author(s):  
KJ Middleton
Keyword(s):  
Field Experiments ◽  
Rhizopus Oryzae ◽  
Causal Agent ◽  
Disease Development ◽  
Atmospheric Humidity ◽  
Protective Barrier ◽  
Head Rot ◽  
And Control ◽  
Established Infection

The causal agent of a common head rot of sunflowers in Queensland was isolated and identified as Rhizopus oryzae. Field experiments were conducted to investigate the environmental and host conditions suitable for disease development, and control of the disease by the use of fungicides. The disease occurs in wound inoculated plants when atmospheric humidity is high. Dicloran is capable of restricting established infection, but wound inoculations made after the application of the fungicide avoid the protective barrier and are uninfluenced by it. The possible use of chemicals to control the disease is discussed.

EPIDEMIOLOGY AND CONTROL OF A SUNFLOWER HEAD ROT IN ISRAEL CAUSED BY RHIZOPUS ARRHIZUS

1970 ◽  
Vol 50 (3) ◽  
pp. 283-288 ◽  
Author(s):  
M. ARNAN ◽  
M. J. PINTHUS ◽  
R. G. KENNETH
Keyword(s):  
Helianthus Annuus ◽  
Soft Rot ◽  
Causal Agent ◽  
Rhizopus Arrhizus ◽  
Single Application ◽  
Helianthus Annuus L ◽  
Head Rot ◽  
And Control

Injury of the heads was found to be necessary for the infection of sunflower (Helianthus annuus L.) by Rhizopus arrhizus Fischer, identified as the causal agent of a soft rot. Infection did not take place before flowering. Birds visiting the heads in search of seed were implicated in the spread of the disease. The disease was controlled by a single application of Copper 8-quinolinolate.

scholarly journals Coccinonectria pachysandricola, Causal Agent of a New Foliar Blight Disease of Sarcococca hookeriana

Plant Disease ◽  
2019 ◽  
Vol 103 (6) ◽  
pp. 1337-1346 ◽  
Author(s):  
Catalina Salgado-Salazar ◽  
Nina Shiskoff ◽  
Nicholas LeBlanc ◽  
Adnan A. Ismaiel ◽  
Maxton Collins ◽  
...  
Keyword(s):  
Woody Plants ◽  
Causal Agent ◽  
Washington Dc ◽  
Disease Symptoms ◽  
Foliar Blight ◽  
Pathogenicity Tests ◽  
Artificial Inoculations ◽  
Blight Disease ◽  
Genome Assemblies ◽  
Severe Leaf

Woody plants of the Buxaceae, including species of Buxus, Pachysandra, and Sarcococca, are widely grown evergreen shrubs and groundcovers. Severe leaf spot symptoms were observed on S. hookeriana at the U.S. National Arboretum in Washington, DC, in 2016. Affected plants were growing adjacent to P. terminalis exhibiting Volutella blight symptoms. Fungi isolated from both hosts were identical based on morphology and multilocus phylogenetic analysis and were identified as Coccinonectria pachysandricola (Nectriaceae, Hypocreales), causal agent of Volutella blight of Pachysandra species. Pathogenicity tests established that Co. pachysandricola isolated from both hosts caused disease symptoms on P. terminalis and S. hookeriana, but not on B. sempervirens. Artificial inoculations with Pseudonectria foliicola, causal agent of Volutella blight of B. sempervirens, did not result in disease on P. terminalis or S. hookeriana. Wounding enhanced infection by Co. pachysandricola and Ps. foliicola on all hosts tested but was not required for disease development. Genome assemblies were generated for the Buxaceae pathogens that cause Volutella diseases: Co. pachysandricola, Ps. buxi, and Ps. foliicola; these ranged in size from 25.7 to 28.5 Mb. To our knowledge, this foliar blight of S. hookeriana represents a new disease for this host and is capable of causing considerable damage to infected plants.

scholarly journals Kualitas Minyak Bunga Matahari Komersial dan Minyak Hasil Ekstraksi Biji Bunga Matahari (Helianthus annuus L.)

2012 ◽  
Vol 12 (1) ◽  
pp. 59 ◽  
Author(s):  
Dewa G Katja
Keyword(s):  
Fatty Acid ◽  
Free Fatty Acid ◽  
Moisture Content ◽  
Helianthus Annuus ◽  
Peroxide Value ◽  
Sunflower Seed ◽  
Seed Oil ◽  
Helianthus Annuus L ◽  
Sunflower Seed Oil

KUALITAS MINYAK BUNGA MATAHARI KOMERSIAL DAN MINYAK HASIL EKSTRAKSI BIJI BUNGA MATAHARI (Helianthus annuus L.) ABSTRAK Minyak komersial dan minyak hasil ekstrasi dari biji bunga matahari melalui uji kadar air, kadar asam lemak bebas, bilangan peroksida. Analisis hasil ekstrak biji bunga matahari diperoleh kadar air 0,43%, kadar asam lemak bebas 0,47% dan bilangan persoksida 5,22 mek/kg. analisis minyak komersial diperoleh kadar air 0,21%, kadar asam lemak bebas 0,28% dan bilangan peroksida 4,18 mek/kg. Hasil analisis dengan kromatografi gas kedua sampel menunjukkan kadar asam lemak bebas berbeda.       Berdasarkan uji kualitas yang dilakukan terhadap kedua sampel yang dianalisis terdapat hasil yang diperoleh tidak memenuhi syarat yang ditentukan yakni kadar asam lemak bebas 0,08% dan bilangan peroksida 2 mek/kg. Kata kunci: Asam lemak bebas, bilangan proksida, minyak biji bunga matahari  QUALITY OF COMMERCIAL SUNFLOWER OIL AND OIL EXTRACTION SEEDS SUNFLOWER (Helianthus annuus L.) ABSTRACT Experimental study of analyzing the extract oil from sunflower seed compare with the commercial sunflower seed oil according to the company standard which includes determining of moisture content, free fatty acid content, peroxide value and the fatty acids compositions is reported in this paper. The result show that the moisture content of the extract oil is 0,43%, free fatly acid content is 0,47%, and the peroxide value is 5,22% mek/Kg. For the commercial sunflower seed oil company product that is 0,21% for the moisture, free fatty acid is 0,28% and the peroxide value is 4,89 mek/Kg. The gas chromatography analysis indicated that the most fatty acid from both samples is linoleic acid. The quality of the extract sunflower seed oil has not been improved to conform with the commercial quality according to the company standard, that is 0,08% for the free fatty acid and 2 mek/Kg for the peroxide value. Keywords: Free fatty acid, peroxide value, sunflower seeds oil

scholarly journals BROWN ROOT ROT DISEASE OF CASHEW IN WEST NUSA TENGGARA: DISTRIBUTION AND ITS CAUSAL ORGANISM

2016 ◽  
Vol 5 (1) ◽  
pp. 32
Author(s):  
Supriadi Supriadi ◽  
E.M. Adhia ◽  
D. Wahyuno ◽  
S. Rahayuningsih ◽  
N. Karyani ◽  
...  
Keyword(s):  
Root Rot ◽  
Causal Agent ◽  
Causal Organism ◽  
Disease Symptoms ◽  
Root Rot Disease ◽  
Lannea Coromandelica ◽  
Leaf Yellowing ◽  
Medicinal Crops ◽  
Rot Disease ◽  
Brown Root Rot

Brown root rot disease is a major constraint on cashew plantation in Pekat District, West Nusa Tenggara. Its causal agent has not been characterized. This paper describes efforts to study the pathogen, distribution and loss. Field study was conducted in Pekat District in 2003. Laboratory  experiments to isolate and test the causal agent were conducted in the Indonesian Spices and Medicinal Crops Research Institute, Bogor.  Research results showed that the disease was found widespread in several villages in Pekat District, such as Pekat, Beringin Jaya, Sorinomo, and Nangamiro. Total number of died cashew trees was 1,075 equals to 5,106 kg kernel yield lost, worth Rp20.5 million. Infected trees showed leaf yellowing and defoliation leading to die. The lateral and taproots near collar were encrusted with gravel, earth, and brown mycelia sleeves. The fungus produced arthrospores and brown pigmentation on agar medium containing 0.05% gallic acid. An isolate of the fungus induced typical disease symptoms following inoculation on 5 month-old cashew seedlings. These results indicated that the causal agent of mass decline of cashew in Pekat District is Phellinus noxius. In field, the fungus also infects a barrier tree (Lannea coromandelica [Houtt.] Merr.) (Anacardiaceae), locally known as kedondong pagar or kayu bantenan.

scholarly journals Methyljasmonate and salicylic acid contribute to the control of Tilletia controversa Kühn, causal agent of wheat dwarf bunt

2020 ◽  
Vol 10 (1) ◽  
Author(s):  
Ghulam Muhae-Ud-Din ◽  
Delai Chen ◽  
Taiguo Liu ◽  
Wanquan Chen ◽  
Li Gao
Keyword(s):  
Fungal Pathogen ◽  
Causal Agent ◽  
Disease Symptoms ◽  
Defence Genes ◽  
The World ◽  
Tilletia Controversa ◽  
High Level ◽  
And Control ◽  
Dwarf Bunt

Abstract Tilletia controversa Kühn (TCK) is the causal agent of dwarf bunt of wheat, a destructive disease in wheat-growing regions of the world. The role of Meja, SA and Meja + SA were characterized for their control of TCK into roots, coleoptiles and anthers. The response of the defence genes PR-10a, Catalase, COI1-1, COII-2 and HRin1 was upregulated by Meja, SA and Meja + SA treatments, but Meja induced high level of expression compared to SA and Meja + SA at 1, 2, and 3 weeks in roots and coleoptiles, respectively. The severity of TCK effects in roots was greater at 1 week, but it decreased at 2 weeks in all treatments. We also investigated TCK hyphae proliferation into coleoptiles at 3 weeks and into anthers to determine whether hyphae move from the roots to the upper parts of the plants. The results showed that no hyphae were present in the coleoptiles and anthers of Meja-, SA- and Meja + SA-treated plants, while the hyphae were located on epidermal and sub-epidermal cells of anthers. In addition, the severity of hyphae increased with the passage of time as anthers matured. Bunted seeds were observed in the non-treated inoculated plants, while no disease symptoms were observed in the resistance of inducer treatments and control plants. Plant height was reduced after TCK infection compared to that of the treated inoculated and non-inoculated treatments. Together, these results suggested that Meja and SA display a distinct role in activation of defence genes in the roots and coleoptiles and that they eliminate the fungal pathogen movement to upper parts of the plants with the passage of time as the anthers mature.

scholarly journals Rhizopus Head Rot of Confectionery Sunflower: Effects on Yield Quantity and Quality and Implications for Disease Management

1997 ◽  
Vol 87 (12) ◽  
pp. 1226-1232 ◽  
Author(s):  
D. Shtienberg
Keyword(s):  
Growth Stage ◽  
Field Experiments ◽  
Rhizopus Oryzae ◽  
Development Stage ◽  
Crop Growth ◽  
Growth Stages ◽  
Yield Quality ◽  
Crop Growth Stage ◽  
Head Rot ◽  
The Individual

The effects of Rhizopus head rot, caused by Rhizopus oryzae, on the yield of confectionery sunflower and its quality were studied in field experiments conducted from 1994 to 1996. The extent of yield loss was related to the crop growth stage at inoculation. When heads were inoculated at the budding stage, loss was not apparent, because inoculated heads were not infected. When inoculated at the anthesis stage, loss was relatively high (42.5 to 99.1%), and both the number of achenes per head and the individual achene weight were reduced. When heads were inoculated at the seed development stage, yield was not reduced significantly (although the entire receptacle was rotted). Effects of Rhizopus head rot on measures of yield quality were examined as well. Inoculation with R. oryzae did not affect the size of the achenes at any crop growth stage. In contrast, the incidence of discolored achenes (an external sign of nutmeats with a bitter off-flavor) was affected by the disease at all crop growth stages. A survey in eight commercial fields from 1992 to 1996 found that, by the end of the season, incidence of disease ranged from 2.3 to 17.4%. However, since disease intensified late, resultant yield losses were minor and did not exceed 3.1%. Loss figures were estimated by means of a model that was developed and validated in the field experiments. The disease did affect the incidence of discolored achenes. Thus, the conclusion drawn is that the effects of Rhizopus head rot in confectionery sunflower on crop yield is of minimal concern, at least when disease intensifies late, as was the case in the studied fields, but management of the disease should be considered in some situations. The objectives would be to prevent a reduction in yield quality, not yield quantity.

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