Role of Epidemiological and Biochemical Factors against Early Blight of Potato

Epidemiological and biochemical factors play a significant role in early blight disease development in potatoes. For this 29 test cultivars/ lines, were screened, 15 lines including Cardinal and Desiree were found to be very highly susceptible. Eight lines including Diament FSD-White, and TPS-9813 showed highly susceptible response. Two lines i.e. 9802 and 396266-33 were susceptible. Only one variety /advanced line FD-1-8 was found to be resistant. None of the 29 advanced lines was found to be highly resistant while two lines such as FD-3-9 and FD-48-41 were shown moderately resistant response. At varietal level, among 29 test varieties/ advanced lines, all the varieties showed highly significant correlation with minimum temperature and negative correlation with maximum temperature. 18 varieties/advanced lines have significant correlation with pan evaporation. Whereas all the 29 varieties/ advanced lines did not show any correlation with relative humidity and wind speed. Five varieties/ advanced lines namely Cardinal, 396240-181, 9803, FD-1-9 and 9801 were selected to study the relationship of environmental conditions with disease severity. Maximum disease severity was recorded at 17-200C maximum temperature, 6-9oC of minimum air temperature and 1.9-2.4 mm pan evaporation. Relative humidity and wind speed almost had no significant effect on disease severity. On varietal level early blight disease severity had significant correlation with phenolic production both in leaves and tubers. Among 29 varieties, 20 varieties had significant correlation with phenolic production while 9 had no correlation in case of leaves while in case of tubers 19 varieties/ lines showed significant correlation 10 lines did not show any correlation with phenolics production.

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OPTIMIZATION OF ENVIRONMENTAL FACTORS CONDUCIVE FOR STRIPE RUST OF WHEAT

Pakistan Journal of Phytopathology ◽

10.33866/phytopathol.029.02.0400 ◽

2017 ◽

Vol 29 (2) ◽

pp. 239

Author(s):

Yasir Ali ◽

Muhammad A. Khan ◽

Muhammad Atiq ◽

Waseem Sabir ◽

Arslan Hafeez ◽

...

Keyword(s):

Wind Speed ◽

Relative Humidity ◽

Environmental Factors ◽

Disease Severity ◽

Puccinia Striiformis ◽

Yellow Rust ◽

Maximum Temperature ◽

Wheat Crop ◽

Severe Condition ◽

Wheat Diseases

Wheat rusts are the significant diseases of wheat crop and potential threats worldwide. Among all major wheat diseases occurring in all wheat growing areas of the world, yellow rust caused by Puccinia striiformis f. sp. tritici is a big hazard when it occurs in severe condition. The susceptible germplasm and conducive environmental conditions contribute towards wide outbreak of rust diseases. In the present study, eight wheat lines were screened out and correlated with epidemiological factors (temperature, relative humidity, rainfall and wind speed). Results showed that maximum disease severity was observed at minimum and maximum temperature ranging from 13.7-16.7 and 23.5-27.65 0C respectively. Their disease severity was increased with increase in relative humidity ranging from 52-64 %. Similarly, rain fall ranging from 5.7-21.99 mm and wind speed 6.88-11.73 km/h respectively proved conducive for yellow rust development in Sargodha. A positive correlation was observed between disease severity and all environmental factors.

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Meteorological Factors Affecting Pan Evaporation in the Haihe River Basin, China

Water ◽

10.3390/w11020317 ◽

2019 ◽

Vol 11 (2) ◽

pp. 317 ◽

Cited By ~ 4

Author(s):

Zhihong Yan ◽

Shuqian Wang ◽

Ding Ma ◽

Bin Liu ◽

Hong Lin ◽

...

Keyword(s):

Wind Speed ◽

Relative Humidity ◽

Minimum Temperature ◽

Sunshine Duration ◽

Maximum Temperature ◽

Haihe River Basin ◽

Pan Evaporation ◽

Haihe River ◽

Average Temperature ◽

The Haihe River Basin

Pan evaporation (Epan) is an important indicator of regional evaporation intensity and degree of drought. However, although more evaporation is expected under rising temperatures, the reverse trend has been observed in many parts of the world, known as the “pan evaporation paradox”. In this paper, the Haihe River Basin (HRB) is divided into six sub-regions using the Canopy and k-means (The process for partitioning an N-dimensional population into k sets on the basis of a sample is called “k-means”) to cluster 44 meteorological stations in the area. The interannual and seasonal trends and the significance of eight meteorological indicators, including average temperature, maximum temperature, minimum temperature, precipitation, relative humidity, sunshine duration, wind speed, and Epan, were analyzed for 1961 to 2010 using the trend-free pre-whitening Mann-Kendall (TFPW-MK) test. Then, the correlation between meteorological elements and Epan was analyzed using the Spearman correlation coefficient. Results show that the average temperature, maximum temperature, and minimum temperature of the HRB increased, while precipitation, relative humidity, sunshine duration, wind speed and Epan exhibited a downward trend. The minimum temperature rose 2 and 1.5 times faster than the maximum temperature and average temperature, respectively. A significant reduction in sunshine duration was found to be the primary factor in the Epan decrease, while declining wind speed was the secondary factor.

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Impact of weather parameters on alternaria blight of Indian mustard [(Brassica juncea (L.) Czern. & Coss.)]

Bangladesh Journal of Botany ◽

10.3329/bjb.v50i1.52663 ◽

2021 ◽

Vol 50 (1) ◽

pp. 15-19

Author(s):

Rakesh Punia ◽

Pavitra Kumari ◽

Anil Kumar ◽

AS Rathi ◽

Ram Avtar

Keyword(s):

Wind Speed ◽

Relative Humidity ◽

Disease Severity ◽

Vapour Pressure ◽

Minimum Temperature ◽

Indian Mustard ◽

Maximum Increase ◽

Alternaria Blight ◽

Progress Curve ◽

Sunshine Hours

Progression of Alternaria blight disease was measured on two susceptible Indian mustard varieties viz., RH 30 and RH 0749 sown at three different dates. The maximum increase in disease severity was recorded between first weeks of February and last week of February. During this period, the maximum and minimum temperature, relative humidity at morning and evening, average vapour pressure of morning and evening, maximum and bright sunshine hours and wind speed were higher, which resulted in congenial conditions for severe infection by the pathogen. The disease severity was positively correlated with maximum and minimum temperature, average vapour pressure, wind speed, sunshine hours and evaporation, while relative humidity and rainfall negatively correlated with Alternaria blight on both the varieties. A maximum value of area under disease progress curve was observed on cultivar RH 30 (651.1 cm2) as compared to RH 0749 (578.9 cm2), when crop was sown on 9th November.

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Evaluation of various plant extracts against the early blight disease of tomato plants under greenhouse and field conditions

Plant Protection Science ◽

10.17221/14/2011-pps ◽

2012 ◽

Vol 48 (No. 2) ◽

pp. 74-79 ◽

Cited By ~ 19

Author(s):

S.M.A. Nashwa ◽

K.A.M. Abo-Elyousr

Keyword(s):

Disease Severity ◽

Plant Extracts ◽

Mycelial Growth ◽

Early Blight ◽

Field Conditions ◽

Nerium Oleander ◽

Tomato Plants ◽

Infected Control ◽

Blight Disease

The antimicrobial activity of six plant extracts from Ocimum basilicum (Sweat Basil), Azadirachta indica (Neem), Eucalyptus chamadulonsis (Eucalyptus), Datura stramonium (Jimsonweed), Nerium oleander (Oleander), and Allium sativum (Garlic) was tested for controlling Alternaria solani in vitro and in vivo. In in vitro study the leaf extracts of D. stramonium, A. indica, and A. sativum at 5% concentration caused the highest reduction of mycelial growth of A. solani (44.4, 43.3 and 42.2%, respectively), while O. basilicum at 1% and 5% concentration and N. oleander at 5% concentration caused the lowest inhibition of mycelial growth of the pathogen. In greenhouse experiments the highest reduction of disease severity was achieved by the extracts of A. sativum at 5% concentration and D. stramonium at 1% and 5% concentration. The greatest reduction of disease severity was achieved by A. sativum at 5% concentration and the smallest reduction was obtained when tomato plants were treated with O. basilicum at 1% and 5% concentration (46.1 and 45.2 %, respectively). D. stramonium and A. sativum at 5% concentration increased the fruit yield by 76.2% and 66.7% compared to the infected control. All treatments with plant extracts significantly reduced the early blight disease as well as increased the yield of tomato compared to the infected control under field conditions.

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SEASONAL AND INTERANNUAL PATTERN OF METEOROLOGICAL VARIABLES IN CUIABÁ, MATO GROSSO STATE, BRAZIL

Brazilian Journal of Geophysics ◽

10.22564/rbgf.v33i3.949 ◽

2015 ◽

Vol 33 (3) ◽

pp. 477 ◽

Cited By ~ 2

Author(s):

Nadja Gomes Machado ◽

Marcelo Sacardi Biudes ◽

Carlos Alexandre Santos Querino ◽

Victor Hugo De Morais Danelichen ◽

Maísa Caldas Souza Velasque

Keyword(s):

Wind Speed ◽

Relative Humidity ◽

Meteorological Data ◽

Seasonal Pattern ◽

Global Radiation ◽

Meteorological Variables ◽

Maximum Temperature ◽

Wet Season ◽

Agricultural Producers ◽

Mato Grosso

ABSTRACT. Cuiab´a is located on the border of the Pantanal and Cerrado, in Mato Grosso State, which is recognized as one of the biggest agricultural producers of Brazil. The use of natural resources in a sustainable manner requires knowledge of the regional meteorological variables. Thus, the objective of this study was to characterize the seasonal and interannual pattern of meteorological variables in Cuiab´a. The meteorological data from 1961 to 2011 were provided by the Instituto Nacional de Meteorologia (INMET – National Institute of Meteorology). The results have shown interannual and seasonal variations of precipitation, solar radiation, air temperature and relative humidity, and wind speed and direction, establishing two main distinct seasons (rainy and dry). On average, 89% of the rainfall occurred in the wet season. The annual average values of daily global radiation, mean, minimum and maximum temperature and relative humidity were 15.6 MJ m–2 y–1, 27.9◦C, 23.0◦C, 30.0◦C and 71.6%, respectively. Themaximum temperature and the wind speed had no seasonal pattern. The wind speed average decreased in the NWdirectionand increased in the S direction.Keywords: meteorological variables, climatology, ENSO. RESUMO. Cuiabá está localizado na fronteira do Pantanal com o Cerrado, no Mato Grosso, que é reconhecido como um dos maiores produtores agrícolas do Brasil. A utilização dos recursos naturais de forma sustentável requer o conhecimento das variáveis meteorológicas em escala regional. Assim, o objetivo deste estudo foi caracterizar o padrão sazonal e interanual das variáveis meteorológicas em Cuiabá. Os dados meteorológicos de 1961 a 2011 foram fornecidos pelo Instituto Nacional de Meteorologia (INMET). Os resultados mostraram variações interanuais e sazonais de precipitação, radiação solar, temperatura e umidade relativa do ar e velocidade e direção do vento, estabelecendo duas principais estações distintas (chuvosa e seca). Em média, 89% da precipitação ocorreu na estação chuvosa. Os valores médios anuais de radiação diária global, temperatura do ar média, mínima e máxima e umidade relativa do ar foram 15,6 MJ m–2 y–1, 27,9◦C, 23,0◦C, 30,0◦C e 71,6%, respectivamente. A temperatura máxima e a velocidade do vento não tiveram padrão sazonal. A velocidade média do vento diminuiu na direção NW e aumentou na direção S.Palavras-chave: variáveis meteorológicas, climatologia, ENOS.

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Influence of weather parameters on alternaria leaf blight severity of makhana under the agro-climate of Koshi region of Bihar

Journal of Agrometeorology ◽

10.54386/jam.v23i1.88 ◽

2021 ◽

Vol 23 (1) ◽

pp. 54-59

Author(s):

SANTOSH KUMAR ◽

MD. NADEEM AKHTAR ◽

SANTOSH KUMAR ◽

MAHESH KUMAR ◽

TRIBHUWAN KUMAR

Keyword(s):

High Temperature ◽

Relative Humidity ◽

Disease Severity ◽

Infection Process ◽

Leaf Blight ◽

Alternaria Leaf Blight ◽

Weather Parameters ◽

Maximum Temperatures ◽

Blight Disease ◽

Cent Disease

Weather parameters play a pivotal role in the infection process and spread of pathogen. It also influences the expression of susceptibility/resistance of the host plant during post-infection phases. Therefore, an experiment was conducted for two consecutive cropping seasons (2018 &2019) to study the influence of weather parameters such as temperature, humidity, rainfall and wind direction on the emergence of alternaria leaf blight of makhana in Koshi region of Bihar. Maximum per cent disease severity of alternarialeaf blightwas observed during the peak monsoon months (June to August). Highest disease severity of leaf blight (14.80% & 15.7%) was observed in the mid June during crop season, 2018 and 2019. High temperature (36.9oC & 38.1oC), and relative humidity (94% & 96.4%) of both the year 2018 and 2019 were found correlated with higher severity to alternaria leaf blight. Similarly average HTR values (3.1) were also found correlated with the average high temperature and relative humidity of both years (2018 and 2019) in terms of severity of leaf blight disease. Maximum temperatures, relative humidity and rainfall exhibited strong positive linear relationship and influenced the occurrence of alternaria leaf blight disease significantly. We also developed a geo-phytopathological model for the prediction of alternaria leaf blight disease of makhana on the basis of congenial mean temperature and relative humidity.

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Monthly pan evaporation modelling using multiple linear regression and artificial neural network techniques

Water Science & Technology Water Supply ◽

10.2166/ws.2019.189 ◽

2019 ◽

Vol 20 (3) ◽

pp. 800-808

Author(s):

G. T. Patle ◽

M. Chettri ◽

D. Jhajharia

Keyword(s):

Neural Network ◽

Artificial Neural Network ◽

Wind Speed ◽

Relative Humidity ◽

Linear Regression ◽

Multiple Linear Regression ◽

Accurate Estimation ◽

Pan Evaporation ◽

Ann Models ◽

Artificial Neural

Abstract Accurate estimation of evaporation from agricultural fields and water bodies is needed for the efficient utilisation and management of water resources at the watershed and regional scale. In this study, multiple linear regression (MLR) and artificial neural network (ANN) techniques are used for the estimation of monthly pan evaporation. The modelling approach includes the various combination of six measured climate parameters consisting of maximum and minimum air temperature, maximum and minimum relative humidity, sunshine hours and wind speed of two stations, namely Gangtok in Sikkim and Imphal in the Manipur states of the northeast hill region of India. Average monthly evaporation varies from 0.62 to 2.68 mm/day for Gangtok, whereas it varies from 1.4 to 4.3 mm/day for Imphal during January and June, respectively. Performance of the developed MLR and ANN models was compared using statistical indices such as coefficient of determination (R2), root mean square error (RMSE) and mean absolute error (MAE) with measured pan evaporation values. Correlation analysis revealed that temperature, wind speed and sunshine hour had positive correlation, whereas relative humidity had a negative correlation with pan evaporation. Results showed a slightly better performance of the ANN models over the MLR models for the prediction of monthly pan evaporation in the study area.

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Spatiotemporal Variability of Potential Evaporation in Heihe River Basin Influenced by Irrigation

10.5194/egusphere-egu2020-12520 ◽

2020 ◽

Author(s):

Congying Han

Keyword(s):

Wind Speed ◽

Relative Humidity ◽

Spatial Pattern ◽

River Basin ◽

Meteorological Factors ◽

Heihe River Basin ◽

Spatiotemporal Variability ◽

Maximum Temperature ◽

Heihe River ◽

Potential Evaporation

Spatiotemporal Variability of Potential Evaporation in Heihe River Basin Influenced by Irrigation Congying Han1,2, Baozhong Zhang1,2, Songjun Han1,21 State Key Laboratory of Simulation and Regulation of Water Cycle in River Basin, China Institute of Water Resources and Hydropower Research, Beijing 100038, China.2 National Center of Efficient Irrigation Engineering and Technology Research-Beijing, Beijing 100048, China.Corresponding author: Baozhong Zhang ([email protected])Abstract: Potential evaporation is a key factor in crop water requirement estimation and agricultural water resource planning. The spatial pattern and temporal changes of potential evaporation calculated by Penman equation (EPen) (1970-2017) in Heihe River Basin (HRB), Northwest China were evaluated by using data from 10 meteorological stations, with a serious consideration of the influences of irrigation development. Results indicated that the spatial pattern of annual EPen in HRB was significantly different, among which the EPen of agricultural sites (average between 1154 mm and 1333 mm) was significantly higher than that of natural sites (average between 794 mm and 899 mm). Besides, the coefficient of spatial variation of the aerodynamic term (Eaero) was 0.4, while that of the radiation term (Erad) was 0.09. The agricultural irrigation water withdrawal increased annually before 2000, but decreased significantly after 2000 which was influenced by the agricultural development and the water policy. Coincidentally, the annual variation of Epen in agricultural sites decreased at -40 mm/decade in 1970-2000 but increased at 60 mm/decade in 2001-2017, while that in natural sites with little influence of irrigation, only decreased at -0.5mm/decade in 1970-2000 but increased at 11 mm/decade in 2001-2017. So it was obvious that irrigation influenced Epen significantly and the change of Epen was mainly caused by the aerodynamic term. The analysis of the main meteorological factors that affect Epen showed that wind speed had the greatest impact on Epen of agricultural sites, followed by relative humidity and average temperature, while the meteorological factors that had the greatest impact on Epen of natural sites were maximum temperature, followed by wind speed and relative humidity.

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Assessment of the future climate potential for tourism over Europe using a combination of downscaling approaches and quantitative impact models

10.5194/egusphere-egu2020-5037 ◽

2020 ◽

Author(s):

Maria Francisca Cardell ◽

Arnau Amengual ◽

Romualdo Romero

Keyword(s):

Climate Change ◽

Wind Speed ◽

Relative Humidity ◽

Future Climate ◽

Cumulative Distribution ◽

Maximum Temperature ◽

Model Errors ◽

Present Climate ◽

Ensemble Strategy ◽

The Future

Europe and particularly, the Mediterranean countries, are among the most visited tourist destinations worldwide, while it is also recognized as one of the most sensitive regions to climate change. Climate is a key resource and even a limiting factor for many types of tourism. Owing to climate change, modified patterns of atmospheric variables such as temperature, rainfall, relative humidity, hours of sunshine and wind speed will likely affect the suitability of the European destinations for certain outdoor leisure activities.Perspectives on the future of second-generation climate indices for tourism (CIT) that depend on thermal, aesthetic and physical facets are derived using model projected daily atmospheric data and present climate &#8220;observations&#8221;. Specifically, daily series of 2-m maximum temperature, accumulated precipitation, 2-m relative humidity, mean cloud cover and 10-m wind speed from ERA-5 reanalysis are used to derive the present climate potential. For projections, the same daily variables have been obtained from a set of regional climate models (RCMs) included in the European CORDEX project, considering the rcp8.5 future emissions scenario. The adoption of a multi-model ensemble strategy allows quantifying the uncertainties arising from the model errors and the GCM-derived boundary conditions. To properly derive CITs at local scale, a quantile&#8211;quantile adjustment has been applied to the simulated regional scenarios. The method detects changes in the continuous CIT cumulative distribution functions (CDFs) between the recent past and successive time slices of the simulated climate and applies these changes, once calibrated, to the observed CDFs.&#160;Assessments on the future climate potential for several types of tourist activities in Europe (i.e., sun, sea and sand (3S) tourism, cycling, cultural, football, golf, nautical and hiking) will be presented by applying suitable quantitative indicators of CIT evolutions adapted to regional contexts. It is expected that such kind of information will ultimately benefit the design of mitigation and adaptation strategies of the tourist sector.

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Studies on some diseases of fruits and vegetable crops in relation to meteorological parameters

MAUSAM ◽

10.54302/mausam.v51i3.1785 ◽

2021 ◽

Vol 51 (3) ◽

pp. 269-274

Author(s):

S. V. DATAR ◽

R. C. DUBEY ◽

N. CHATTOPADHYAY

Keyword(s):

Relative Humidity ◽

Minimum Temperature ◽

Early Blight ◽

Meteorological Parameters ◽

Maximum Temperature ◽

Vegetable Crops ◽

Correlation Techniques

The role of different meteorological parameters controlling the incidences of some diseases on tomato, guava and fig grown at Pune and Padegaon in Maharashtra state were studied by graphical superimposition and correlation techniques. Peak infestation of rust on fig was observed in January at Padegaon whereas maximum infestation of fruit canker on guava and early blight on tomato were reported respectively from September to first week of October and September to November at Pune. Increase in maximum temperature was found to increase the infestation of both fruit canker and early blight. Decrease in afternoon relative humidity favoured the infestation of fruit canker and rust. Fall of minimum temperature and rise in bright hours of sunshine also aggravated the incidences of fruit canker and rust respectively.

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