scholarly journals ​Effect of Temperature and pH on Growth of Alternaria tagetica, Leaf Blight of Marigold

Author(s):  
Karuna Chandrakant Kurhade ◽  
Hanumant Dnyandeo Gangawane ◽  
C.D. Deokar ◽  
K.S. Raghuwanshi

Marigold (Tagets erecta) is one of the most important major floriculture crop in India. The leaf blight of marigold is caused by Alternaria tagetica is becoming a common disease on marigold Alternaria blight appeared in mild to severe form in many regions of Maharashtra and sometimes resulting in complete failure of the crop especially during rainy season. The fungal pathogen are greatly influenced by environmental factor therefore the present work undertaken to study the effect of temperature and pH on growth of Alternaria tagetica. The effect of temperature and pH were determined by colony diameter method by using different media like potato dextrose agar and oat meal agar medium. It is clearly evident from the result that all the temperature pH tested showed variation in the diameter of colony. The temperature 25oC encouraged better growth of Alternaria tagetica as compared to 15oC and 35oC. The result also revealed that pH 6 and 7 encouraged better growth of Alternaria tagetica it is concluded from the result that temperature 25oC and pH 6 is optimum temperature and pH for the growth Alternaria tagetica.

Author(s):  
Karuna Chandrakant Kurhade ◽  
Hanumant Dnyandeo Gangawane ◽  
C.D. Deokar ◽  
K.S. Raghuwanshi

Marigold (Tagets erecta) is one of the most important major floriculture crop in India. The leaf blight of marigold is caused by Alternaria tagetica is becoming a common disease on marigold Alternaria blight appeared in mild to severe form in many regions of Maharashtra and sometimes resulting in complete failure of the crop especially during rainy season. The fungal pathogen are greatly influenced by environmental factor therefore the present work undertaken to study the effect of temperature and pH on growth of Alternaria tagetica. The effect of temperature and pH were determined by colony diameter method by using different media like potato dextrose agar and oat meal agar medium. It is clearly evident from the result that all the temperature pH tested showed variation in the diameter of colony. The temperature 25oC encouraged better growth of Alternaria tagetica as compared to 15oC and 35oC. The result also revealed that pH 6 and 7 encouraged better growth of Alternaria tagetica it is concluded from the result that temperature 25oC and pH 6 is optimum temperature and pH for the growth Alternaria tagetica.


2016 ◽  
Vol 2 (2) ◽  
pp. 221-228 ◽  
Author(s):  
Monzur Morshed Ahmed ◽  
Md Fakruddin ◽  
Md Nur Hossain ◽  
Khandaker Rayhan Mahbub ◽  
Abhijit Chowdhury

Aspergillus flavus strains were isolated from locally available poultry feeds. Effect of temperature, pH and culture media on growth of Aspergillus flavus was studied. Temperature ranged from 4-42°C (4, 10, 20, 25, 30, 37 and 42°C) was examined. Except for 4°C and 10°C, the isolate was able to grow for the whole temperature range. The growth was maximum at 25°C and was influenced with increasing or decreasing of temperature from 42°C to 20°C.The lag time was strongly influenced by the temperature at lower temperature level than at higher temperature range. Effect of pH on growth of Aspergillus flavus was also examined; from comparison of 3 different pH levels, it is concluded that at most temperatures pH 6.5 showed a higher growth rate and as a consequence required a shorter time to achieve maximum colony diameter. No significant variations in the lag time were observed. A natural poultry feed meal agar medium (FMAM) was developed in the laboratory and growth of A. flavus was compared with other 2 synthetic dehydrated media namely; Czapek’sdox Agar (CDA) and potato dextrose Agar (PDA). Poultry feed meal agar medium showed better growth response than Czapek’sdox agar and potato dextrose agar at all conditions. At 25°C and pH 6.5 found optimum for growth of Aspergillus flavus in feed meal agar medium whereas, temperature 30°C and pH 6.5 found optimum for growth for Czapek’sdox agar media and temperature 30°C and pH 6 showed high growth rate on potato dextrose agar. Poultry feed meal media showed high affinity for growth of mycelium and early spore formation than other media examined.Asian J. Med. Biol. Res. June 2016, 2(2): 221-228


Author(s):  
T. Umamaheswari ◽  
S. K. Beura ◽  
A. Sahoo ◽  
S. Pattanayak

Background: Cotton is one of the most important cash crops in India. It is also called as “White gold” because of its agricultural as well as industrial importance. Myrothecium leaf blight is an emerging disease in cotton which is growing consistently throughout the country and has been reported to cause significant losses in major cotton growing tracts of odisha. Considering the importance of the disease, the present investigation has been taken up to study the physiology of the fungus. Methods: An experiment was conducted in-vitro during 2016-18 to investigate the effect of temperature and pH on the growth of M. roridum. Seven different nutrient media viz. Potato Dextrose Agar (PDA) medium, Potato Sucrose Agar (PSA) medium, Host Leaf Extract Agar (HEA) medium, Potato Carrot Agar (PCA) medium, Czapek’sdox Agar (ZA) medium, Richard’s Agar (RA) medium and Oat meal agar medium (OMA) were tested under in-vitro conditions to ascertain a suitable medium for the growth of M. roridum. Result: The investigation in laboratory conditions has revealed that out of seven nutrient media tested, maximum radial growth was recorded in Potato Sucrose Agar (PSA) with an average radial growth of diameter 76.06 mm and the least growth was recorded on Richard’s Agar with a diameter of 23.66 mm. The growth of the fungus was observed to be maximum at a temperature of 28oC with a diameter of 61.09 mm and the minimum average growth of 17.36 mm was recorded at 36oC. Studies on pH revealed that that the fungus grows well in neutral and slight alkaline medium (6.5 - 8.0).


1958 ◽  
Vol 36 (4) ◽  
pp. 623-628 ◽  
Author(s):  
Premvati

The optimum temperature for the complete development of the free-living and the infective larvae of Strongyloides fülleborni is 25 °C. Morphological changes are seen at higher or lower temperatures.


1991 ◽  
Vol 39 (2) ◽  
pp. 191 ◽  
Author(s):  
JG Hamilton ◽  
MP Zalucki

C. plebejana were reared from egg to adult at a range of constant temperatures. At 10-degrees-C no immature stages survived. Development rates increased over the temperature range 14-34-degrees-C; these were simulated with a non-linear model. Females emerged before males. Fecundity decreased with increased rearing temperature as a direct result of reduced adult female weight. At 34-degrees-C development rate and survival were reduced and all eggs laid were infertile. Optimum temperature for population increase was 28-degrees-C. Validation of a non-linear model for development rate shows that the species of host-plant affects mean development rates of tipworm. Although 5.3 tipworm generations are possible on cotton annually, only one occurs; reasons for this are suggested.


2017 ◽  
Vol 5 (36) ◽  
Author(s):  
Sebastian Albu ◽  
Sandeep Sharma ◽  
Burton H. Bluhm ◽  
Paul P. Price ◽  
Raymond W. Schneider ◽  
...  

ABSTRACT Cercospora cf. sigesbeckiae is an ascomycete fungal pathogen that infects various plants, including important agricultural commodities, such as soybean. Here, we report the first draft genome sequence and assembly of this pathogen.


2001 ◽  
Vol 58 (3) ◽  
pp. 613-616 ◽  
Author(s):  
Sideney Becker Onofre ◽  
Cindia Mara Miniuk ◽  
Neiva Monteiro de Barros ◽  
João Lúcio Azevedo

Entomopathogenic fungi from the genus Metarhizium are largely used for the biological control of agricultural pests by conidia spreading on the field. Although conidia production is well studied in M. anisopliae, only few research studies were done in M. flavoviride. The present work was carried out alming to evaluate the Mycelial growth and sporulation of the entomopathogenic fungus Metarhizium flavoviride var. flavoviride growing at 27 ± 2°C on Potato-dextrose-agar (PDA), Czapek-agar (CZP) and a complete agar medium (CM) under three lighting regimes, (continuous illumination, light/dark cycle and an black light/dark cycle) were investigated. A completely randomized 3 × 3 (culture media × lighting regime) factorial design with four replicates was used. The best mycelial growth and sporulation occurred on the PDA and CM media under continuous illumination (P <= 0,05).


2019 ◽  
Vol 5 (3) ◽  
pp. 105
Author(s):  
Albert Sembiring ◽  
Natalia Lusianingsih Sumanto

Fusarium wilt disease on banana has been known as panama disease one of the main diseases that cause huge losses for banana farmers. It is caused by the soil-borne fungal pathogen, Fusarium oxysporum f.sp cubense (Foc), which is very hard control because it is saprophytic in the soil. The mold infiltrates the root to vascular tissue that induces yellowing on the leaf, so this pathogen can attack the root, stem dan leaf. The research aimed to search bacteria from the banana rhizosphere that have an antifungal activity to inhibit Foc growth. Bacteria was isolated by serial dilution then was spread on King’s B agar medium incubation 28oC (room temperature). Four quadrants in vitro test on PDA medium used twenty bacterial from isolation, from the test was obtained six isolates have the potential to inhibit the growth of Foc. Based on percentage inhibition radial growth four isolates that have inhibition 50% over which TR2 was the highest at 79.07%. The in vitro test confirmed that bacteria from the banana rhizosphere have potential as biocontrol agent because it was able to inhibit the Foc growth.


2009 ◽  
Vol 99 (9) ◽  
pp. 1045-1052 ◽  
Author(s):  
Paul W. Tooley ◽  
Marsha Browning ◽  
Kerrie L. Kyde ◽  
Dana Berner

We investigated the temperature and moisture conditions that allow Phytophthora ramorum to infect Rhododendron ‘Cunningham's White’. Most experiments were performed with a single P. ramorum isolate from the NA1 clonal lineage. For whole plants incubated in dew chambers at 10 to 31°C, the greatest proportion of diseased leaves, 77.5%, occurred at the optimum temperature of 20.5°C. Disease occurred over the entire range of temperatures tested, although amounts of disease were minor at the temperature extremes. For whole plants exposed to varying dew periods at 20°C and then incubated at 20°C for 7 days, a dew period as short as 1 h resulted in a small amount of disease; however, at least 4 h of dew were required for >10% of the leaves to become diseased. Moisture periods of 24 and 48 h resulted in the greatest number of diseased leaves. In detached-leaf, temperature-gradient-plate experiments, incubation at 22°C resulted in the greatest disease severity, followed by 18°C and then 14°C. In detached-leaf, moisture-tent experiments, a 1-h moisture period was sufficient to cause disease on 67 to 73% of leaves incubated for 7 days at 20°C. A statistical model for disease development that combined the effects of temperature and moisture period was generated using nonlinear regression. Our results define temperature and moisture conditions which allow infection by P. ramorum on Cunningham's White rhododendron, and show that P. ramorum is able to infect this host over a wide range of temperatures and moisture levels. The results indicate that P. ramorum has the potential to become established in parts of the United States that are outside its current range.


1947 ◽  
Vol 24 (1-2) ◽  
pp. 79-94
Author(s):  
L. E. S. EASTHAM ◽  
F. SEGROVE

1. The effects of temperature and humidity on the duration of each instar of the life cycle of Calandra granaria Linn. have been examined. The insects were reared at temperatures ranging from 15 to 30° C. and at atmospheric humidities ranging from 40 to 80% R.H. 2. A method is described for assessing the effect of temperature as an independent factor. 3. The temperatures employed fall within the ‘vital zone’. Extrapolation indicates the threshold temperature to be approximately 11° C. for the egg and larval instars though somewhat lower for the pupa. 30° C. is below the optimum temperature. 4. The durations of the egg and pupal stages are not affected by atmospheric humidity. 5. The duration of all larval instars is affected by moisture. It is suggested that this is largely due to atmospheric humidity and that food water is of little significance. 6. Shortage of moisture acts as an obstacle to development. Evidence is presented which indicates that drier atmospheres tend to desiccate the insect and that desiccation is responsible for retarded growth and development. 7. Since much earlier work on temperature and moisture has been done on fasting insects and, therefore, on insects deficient in one of the most important environmental factors, we suggest that our results, incomplete as they are, indicate the need for new approaches to be made. More complete data on feeding insects under controlled conditions of food, temperature and moisture are required, from which can be drawn up more complete balance sheets of development involving measurements of food utilization and respiratory rates.


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