Effect of physico-morphic characters and environmental factors on infestation of thrips (Thrips tabaci) on five onion cultivars

Resistance to plants is frequently associated with physical, morphological, physiological, biochemical, molecular and genetic characteristics of the plants. As very little information is available on the effects of physico-morphic characteristics and environmental factors on thrips (Thrips tabaci) infestation, therefore, in the present study such effects were evaluated on the infestation of thrips on five onion cultivars. Maximum number of adults and infestation of thrips was recorded on Marvi followed by Golden Orb while the adults and infestation was the minimum on Red Orb. Significant variations were observed in plant heights and girths among five onion varieties after 40, 70 and 100 days. Similarly, maximum yield was observed in case of Red Orb followed by F1 Mustang while the minimum yield was obtained with cultivar Marvi. The low temperature, high temperature and average temperature showed significant and positive correlations among all the cultivars. However, the average relative humidity showed negative and non-significant correlation for all the varieties. The correlation between physico-morphic characteristics and adult population was found significant for plant girth after 40 days while the correlations were non-significant for all the other factors. It is concluded from the present studies that Red Orb is comparatively resistant cultivar harboring the minimum thrips population. The highest yield was also recorded in case of Red Orb as compared to other tested cultivars and recommended for cultivation to enhance economic returns of farmers.

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Managing Onion Thrips can Limit Bacterial Stalk and Leaf Necrosis in Michigan Onion Fields

Plant Disease ◽

10.1094/pdis-07-18-1271-re ◽

2019 ◽

Vol 103 (5) ◽

pp. 938-943 ◽

Cited By ~ 1

Author(s):

A. S. Grode ◽

E. Brisco-McCann ◽

P. Wiriyajitsonboom ◽

M. K. Hausbeck ◽

Z. Szendrei

Keyword(s):

Cultural Practices ◽

Disease Incidence ◽

Insect Pest ◽

Management Program ◽

Thrips Tabaci ◽

Onion Thrips ◽

Leaf Necrosis ◽

Positive Correlations ◽

Thrips Population ◽

Reduce Disease Severity

Onion thrips (Thrips tabaci) is a major insect pest of onion and it has been identified as a likely vector of Pantoea agglomerans (bacterial stalk and leaf necrosis), a relatively new pathogen to Michigan’s onion industry. Our objective was to develop an integrated insect and disease management program by examining the efficacy of bactericides and insecticides alone and in combination to limit bacterial stalk and leaf necrosis caused by P. agglomerans. We also examined the association of onion thrips and disease incidence in the field, because thrips are known to transmit this pathogen. In the pesticide trial, insecticides reduced both thrips abundance and bacterial stalk and leaf necrosis incidence whereas bactericides alone did not reduce disease severity. Positive correlations among thrips population density, numbers of thrips positive for P. agglomerans, and bacterial stalk and leaf necrosis incidence in onion fields were determined. This study suggests that onion thrips feeding can facilitate the development of bacterial stalk and leaf necrosis in Michigan’s commercial onion fields, and results from the pesticide trials indicate that thrips feeding damage is positively correlated with disease incidence. Therefore, in order to reduce bacterial stalk and leaf necrosis incidence in onion, management efforts should include reducing onion thrips populations through the use of insecticides and other cultural practices.

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Effects of environmental factors on population dynamics of rice earhead bug and their management with newer insecticide combinations and sole insecticide

Bangladesh Journal of Botany ◽

10.3329/bjb.v48i4.49037 ◽

2019 ◽

Vol 48 (4) ◽

pp. 973-979

Author(s):

Kamal Ravi Sharma ◽

S.V.S. Raju ◽

D. Rakshith Roshan

Keyword(s):

Population Dynamics ◽

Relative Humidity ◽

Environmental Factors ◽

Correlation Analysis ◽

Negative Correlation ◽

Untreated Control ◽

Significant Negative Correlation ◽

Average Temperature ◽

Average Relative Humidity ◽

Weather Parameters

An experiment was conducted to study the population dynamics of rice earhead bug and to evaluate the efficacy of newer insecticide combinations and sole insecticide along with untreated control. The rice earhead bug population was first recorded on 36th standard week as 1 nos./10 sweep nets and peak population (17 nos./10 sweep nets) was observed during 44th standard week. The correlation analysis revealed that rice earhead bug showed significant negative correlation with rainfall while the remaining weather parameters like average relative humidity and average temperature were found negative and non-significantly correlated. The overall data of efficacy revealed that all insecticidal treatments were significantly superior over untreated control. However, the plots treated with fipronil 5% + buprofezin 20% SC recorded the lowest number of rice earhead bug population (2.10 and 3.51 nos./5 sweep nets) after first and second insecticidal sprays, respectively, followed by indoxacarb 10% + thiamethoxam 10% WG (2.47 and 4.25 nos./5 sweep nets, respectively). Whereas, application of thiamethoxam 25% WG and buprofezin 25% singly SC were recorded as third and fourth best treatments, respectively.

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Spatial-Temporal Patterns and Controls of Evapotranspiration across the Tibetan Plateau (2000–2012)

Advances in Meteorology ◽

10.1155/2017/7082606 ◽

2017 ◽

Vol 2017 ◽

pp. 1-12 ◽

Cited By ~ 12

Author(s):

Hao Zhang ◽

Jian Sun ◽

Junnan Xiong

Keyword(s):

Tibetan Plateau ◽

Environmental Factors ◽

Vegetation Type ◽

Middle Part ◽

Rate Of Change ◽

Ecological Indicator ◽

The Tibetan Plateau ◽

Grassland Ecosystems ◽

Key Factor ◽

Positive Correlations

Evapotranspiration (ET) is a key factor to further our understanding of climate change processes, especially on the Tibetan Plateau, which is sensitive to global change. Herein, the spatial patterns of ET are examined, and the effects of environmental factors on ET at different scales are explored from the years 2000 to 2012. The results indicated that a steady trend in ET was detected over the past decade. Meanwhile, the spatial distribution shows an increase of ET from the northwest to the southeast, and the rate of change in ET is lower in the middle part of the Tibetan Plateau. Besides, the positive effect of radiation on ET existed mainly in the southwest. Based on the environment gradient transects, the ET had positive correlations with temperature (R>0.85, p<0.0001), precipitation (R > 0.89, p < 0.0001), and NDVI (R > 0.75, p < 0.0001), but a negative correlation between ET and radiation (R = 0.76, p < 0.0001) was observed. We also found that the relationships between environmental factors and ET differed in the different grassland ecosystems, which indicated that vegetation type is one factor that can affect ET. Generally, the results indicate that ET can serve as a valuable ecological indicator.

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Karakteristik Pengeringan Biji Jagung (Zea Mays L.) Menggunakan Alat Pengering Surya Adriyarkara Termodifikasi

Jurnal Ilmiah Mahasiswa Pertanian ◽

10.17969/jimfp.v3i2.7429 ◽

2018 ◽

Vol 3 (2) ◽

pp. 351-360

Author(s):

Athul Fadhli ◽

Diswandi Nurba ◽

Raida Agustina

Keyword(s):

Zea Mays ◽

Relative Humidity ◽

Moisture Content ◽

Zea Mays L ◽

Initial Moisture Content ◽

Solar Irradiation ◽

Air Velocity ◽

Drying Time ◽

Average Temperature ◽

Average Relative Humidity

Abstrak. Jagung merupakan tanaman penghasil karbohidrat terpenting. Pengeringan jagung pipil menggunakan alat pengering merupakan proses untuk menghasilkan jagung pipil yang siap diolah untuk pembuatan tepung jagung dengan batas kadar air tertentu sehingga menghaslkan jagung pipil dengan kualitas yang baik. Tujuan penelitian ini adalah untuk mengkaji karakteristik pengeringan biji jagung menggunakan alat pengering surya Termodifikasi. Metode penelitian menggunakan 3,15 kilogram jagung pipil dengan kadar air awal 22% untuk proses pengeringan. Parameter yang dianalisis terkait alat pengering kolektor surya yaitu temperatur, kelembaban relatif, kecepatan udara dan iradiasi surya, sedangkan parameter yang dianalisis terkait bahan yaitu kadar air, lama waktu pengeringan, laju pengeringan dan organoleptik. Prosedur penelitian terdiri dari pengujian kosong dan pengujian dengan menggunakan jagung pipil. Hasil penelitian menunjukkan bahwa temperatur rata-rata dalam rak pengering sebelum dilakukan modifikasi yaitu 44,4oC, temperatur rata-rata setelah dilakukan modifikasi yaitu 55,5oC dan temperatur rata-rata rak pengering pada pengeringan menggunakan jagung pipil yaitu 46,96oC. Kelembaban relatif rata-rata dalam rak pengering sebelum dilakukan modifikasi yaitu 40,1%, kelembaban relatif rata-rata dalam rak pengering setelah modifikasi yaitu 35,1% dan kelembaban relatif rata-rata pengeringan menggunakan jagung pipil yaitu 44,45%. Dari hasil pengukuran tersebut menunjukkan bahwa nilai temperatur dan kelembaban pada alat setelah modifikasi lebih baik dibandingkan sebelum alat dimodifikasi. Pengukuran temperatur dan kelembaban relatif terdiri dari 4 titik pengukuran yaitu rak 1A,1B dan rak 2A, 2B. Kecepatan udara rata-rata yang diukur konstan yaitu 0,7 m/s pada ruang pengering, sedangkan lingkungan 1,1 m/s. Total iradiasi surya selama pengeringan yaitu 1848,84 W/m2. Kadar air jagung pipil masing-masing rak yaitu rak 1A 14,29%, rak 1B 14,47%, rak 2A 13,91% dan rak 2B 14,1%. Hasil dari pengujian organoleptik, panelis agak menyukai jagung pipil yang dikeringkan menggunakan alat pengering tersebut.Characteristics of Seed Drying (Zea mays L.) Using a Modified Adriyarkara Solar DryerAbstract. Corn is the most important carbohydrate plant. Drying corn using a drying tool is a process to produce corn that are ready to be processed for making corn flour with a certain water content limit so as to produce corn with good quality. The purpose of this study was to examine the characteristics of drying of corn kernels using a modified solar dryer. The research method used 3,15 kilogram of corn milled with the initial moisture content of 22% for drying process. The parameters analyzed in relation to solar collector dryers are temperature, relative humidity, air velocity and solar irradiation, while the parameters analyzed are materials such as moisture content, drying time, drying rate and organoleptic. The research procedure consists of unloaded testing and testing using corn. The results showed that the average temperature in the dryer tray before modification was 44,4°C, the average temperature after modification was 55,5°C and the average temperature of the dryer tray on drying using corn was 46,96oC. The average relative humidity in the dryer tray before modification is 40,1%, the average relative humidity in the dryer tray after modification is 35,1% and the average relative humidity of drying using corn is 44,45%. From the measurement results show that the value of temperature and humidity in the tool after modification is better than before. Measurement of temperature and relative humidity consist of 4 point of measurement that is tray 1A, 1B and tray 2A, 2B. Average mean air velocity measured is 0,7 m/s at the dryer room, while the environment is 1,1 m/s. Total solar irradiation during drying is 1848,84 W/m2. Moisture level of corn each shelves tray 1A is 14,29%, tray 1B is 14.47%, tray 2A is 13,91% and tray 2B is 14,1%. As a result of organoleptic testing, panelists rather like dried corn using the dryer.

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Impact of the State of Emergency during the COVID-19 Pandemic in 2020 on Asthma Exacerbations among Children in Kobe City, Japan

International Journal of Environmental Research and Public Health ◽

10.3390/ijerph182111407 ◽

2021 ◽

Vol 18 (21) ◽

pp. 11407

Author(s):

Hiroshi Yamaguchi ◽

Kandai Nozu ◽

Shinya Ishiko ◽

Atsushi Kondo ◽

Takeshi Ninchoji ◽

...

Keyword(s):

Environmental Factors ◽

Viral Infections ◽

Multivariate Analyses ◽

The State ◽

State Of Emergency ◽

Average Temperature ◽

Asthma Exacerbations ◽

Number Of Patients ◽

The Impact ◽

Kobe City

The coronavirus disease (COVID-19) pandemic altered environmental factors. We studied the impact of these changes on asthma exacerbation (AE) by comparing the AE-related environmental factors between COVID-19 (2020) and pre-COVID-19 (2011–2019) eras. Between 2011 and 2020, 278,465 children (<16 years old) visited our emergency department, and 7476 were diagnosed with AE. The number of patients showed spring and fall peaks in 2011–2019. Multivariate analyses showed significant positive relationships of the number of AE patients with the average temperature among all patients and 0–5-year-olds and with sulfur dioxide (SO2) levels in 2011–2019 among 0–5-year-olds. Although the spring peak in the number of patients was not observed in 2020 after declaration of a state of emergency, the fall peak was again observed after the state of emergency was lifted. No changes in average temperature were detected, but SO2 was significantly reduced following declaration of the state of emergency in 2020. Therefore, SO2 reduction might have contributed to the disappearance of the peak of AE. However, a fall peak was observed again in 2020, although SO2 levels continued to be low. These data suggest that person to person interaction seems to be associated with AE, presumably due to unknown viral infections.

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The Effect of Temperature and Humidity May Reduce the Growth Rate of the Coronavirus Disease 2019 Epidemic

10.21203/rs.3.rs-27890/v1 ◽

2020 ◽

Author(s):

Lei Qin ◽

Qiang Sun ◽

Jiani Shao ◽

Yang Chen ◽

Xiaomei Zhang ◽

...

Keyword(s):

Growth Rate ◽

Relative Humidity ◽

Effect Of Temperature ◽

Average Temperature ◽

Temperature And Humidity ◽

Scatter Plots ◽

Low Humidity ◽

Average Relative Humidity ◽

Effects Of Temperature ◽

The Relationship

Abstract Background: The effects of temperature and humidity on the epidemic growth of coronavirus disease 2019 (COVID-19)remains unclear.Methods: Daily scatter plots between the epidemic growth rate (GR) and average temperature (AT) or average relative humidity (ARH) were presented with curve fitting through the “loess” method. The heterogeneity across days and provinces were calculated to assess the necessity of using a longitudinal model. Fixed effect models with polynomial terms were developed to quantify the relationship between variations in the GR and AT or ARH.Results: An increased AT dramatically reduced the GR when the AT was lower than −5°C, the GR was moderately reduced when the AT ranged from −5°C to 15°C, and the GR increased when the AT exceeded 15°C. An increasedARH increased theGR when the ARH was lower than 72% and reduced theGR when the ARH exceeded 72%.Conclusions: High temperatures and low humidity may reduce the GR of the COVID-19 epidemic. The temperature and humidity curves were not linearly associated with the COVID-19 GR.

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REACTION OF SPRING WHEAT LINES WITH FOREIGN GENETIC MATERIAL TO THE IMPACT OF ARTIFICIALLY CREATED STRESSES

10.26897/978-5-9675-1855-3-2021-42 ◽

2021 ◽

Author(s):

O. V. Pavlova ◽

◽

L. A. Marchenkova ◽

R. F. Chavdar ◽

T. G. Orlova ◽

...

Keyword(s):

Sodium Chloride ◽

Environmental Factors ◽

Spring Wheat ◽

Genetic Material ◽

Growth Processes ◽

Genetic Characteristics ◽

Early Stages ◽

Inhibition Of Growth ◽

Wheat Lines ◽

The Impact

The adaptive properties of spring wheat lines with foreign genetic material at the early stages of ontogenesis on the backgrounds of salinization with sodium chloride and prolonged flooding of seeds in water were evaluated. In the course of the work, different degrees of inhibition of growth processes were revealed, depending on the factor used and the genetic characteristics of the studied forms, a comprehensive (summary) assessment of the index of stability characterizing adaptability to adverse environmental factors was shown.

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Effect of Climate Change on Agricultural Production

10.4018/978-1-7998-9557-2.ch006 ◽

2022 ◽

pp. 99-114

Author(s):

Helena Esteves Correia ◽

Daniela de Vasconcelos Teixeira Agu Costa

Keyword(s):

Climate Change ◽

Environmental Factors ◽

Light Intensity ◽

Soil Water ◽

Agricultural Production ◽

Co2 Concentration ◽

Atmospheric Co2 ◽

Air Humidity ◽

Ozone Level ◽

Average Temperature

Agricultural production is influenced by environmental factors such as temperature, air humidity, soil water, light intensity, and CO2 concentration. However, climate change has influenced the values of average temperature, precipitation, global atmospheric CO2 concentration, or ozone level. Thus, climate change could lead to different situations on plants and consequently influence agricultural production. With this chapter, the authors intend to research how climate change influences some plant metabolisms (such as photosynthesis, photorespiration, transpiration, among others) and therefore agricultural production.

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Genetic and Environmental Factors Associated to Glutenin Polymer Characteristics of Wheat

Foods ◽

10.3390/foods9050683 ◽

2020 ◽

Vol 9 (5) ◽

pp. 683 ◽

Cited By ~ 2

Author(s):

Gérard Branlard ◽

Annie Faye ◽

Larbi Rhazi ◽

Ayesha Tahir ◽

Véronique Lesage ◽

...

Keyword(s):

Environmental Factors ◽

Grain Protein Content ◽

Gyration Radius ◽

Molecular Characteristics ◽

Climatic Data ◽

Field Flow Fractionation ◽

Factors Associated ◽

Average Temperature ◽

Genetic And Environmental Factors ◽

Glutenin Polymer

The polymers of wheat glutenins are studied here using asymmetric flow field flow fractionation (A4F). Molecular mass (Mw), gyration radius (Rw), and the polydispersity index (PI) of polymers were measured over a four-year, multi-local wheat trial in France. The experiment, involving 11 locations and 192 cultivars, offered the opportunity to approach the genetic and environmental factors associated with the phenotypic values of the polymer characteristics. These characteristics, which were all highly influenced by environmental factors, exhibited low broad-sense heritability coefficients and were not influenced by grain protein content and grain hardness. The 31 alleles encoding the glutenin subunits explained only 17.1, 25.4, and 16.8% of the phenotypic values of Mw, Rw, and PI, respectively. The climatic data revealed that a 3.5 °C increase between locations of the daily average temperature, during the last month of the grain development, caused an increase of more than 189%, 242%, and 434% of the Mw, Rw, and PI, respectively. These findings have to be considered in regard to possible consequences of global warming and health concerns assigned to gluten. It is suggested that the molecular characteristics of glutenins be measured today, especially for research addressing non-celiac gluten sensitivity (NCGS).

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Effects of Canopy Microclimate on Chinese Chestnut (Castanea mollissima Blume) Nut Yield and Quality

Forests ◽

10.3390/f11010097 ◽

2020 ◽

Vol 11 (1) ◽

pp. 97

Author(s):

Yue Wen ◽

Shuchai Su ◽

Haicheng Zhang

Keyword(s):

Environmental Factors ◽

Light Intensity ◽

Chinese Chestnut ◽

Yield And Quality ◽

Canopy Position ◽

Castanea Mollissima ◽

Positive Correlations ◽

The Relationship

There are considerable differences in chestnut yield and quality across different chestnut-producing regions in China, indicating that environmental factors affect these properties of chestnuts. Furthermore, nut yield and quality differ depending on canopy position. Therefore, this study investigated the relationship between the canopy microclimate, nut yield, and quality. We determined microclimate factors from blossoming to ripening at different positions in the canopy. Nut yield and quality and the number of different branch types were measured at various canopy positions. The light intensity and temperature of the different canopy layers exhibited funnel-form distributions ranging from 0 to 3600 μmol·m2·s−1 and from 32 to 37 °C, respectively. Canopy humidity showed an inverted funnel-shaped distribution ranging from 26% to 40%. Nut yield and quality in the top and outer canopies were higher than in the bottom and inner canopies. Branches in the top-middle and peripheral parts of the canopy also produced higher yields, especially strong branches that bore more nuts. Nut yield and quality had positive correlations with light intensity (r = 0.735) and temperature (r = 0.709), whereas they were inversely associated with humidity (r = −0.584). The nut yield was more than 200 gm−3 when the light intensity was above 1500 μmol·m2·s−1, the temperature was above 34.4 °C, and the humidity was below 27.5%.

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