scholarly journals The Dominance of physico-morphic plant traits in regulating population density of Bemisia tabaci and Thrips tabaci in Bt and non-Bt Cotton

1970 ◽  
pp. 28-32
Author(s):  
Mirza Abdul Qayyum, Muhammad Asad Saleem, Muhammad Ishtiaq ◽  
Ghulam Murtaza, Saif Ullah, Aboubakar Siddique
Keyword(s):  
Bemisia Tabaci ◽  
Negative Correlation ◽  
Plant Traits ◽  
Insect Pests ◽  
Research Area ◽  
Climatic Conditions ◽  
Thrips Tabaci ◽  
Maximum Temperature ◽  
Bt Cotton ◽  
Weather Factors

Policy makers, journalists and other commentators often advocate transgenic cotton (Gossypium spp.) as poor-performer against sucking insects that pose a great threat to production targets. A field study was carried out for seasonal occurrence of whitefly (Bemisia tabaci Gennadius) and thrips (Thrips tabaci Lindeman) on two of cotton genotypes namely Bt MNH-992 and non-Bt Cyto-124 under climatic conditions of Multan, Pakistan from July-October, 2017. Impact of environment as a factor was hypothesized on pests on two experimental sites [Research Area (RA) & Farmer Field (FF)]. Maximum population of whitefly at RA (13.5 and 16.7 individuals per plant) for Bt and non-Bt, respectively was recorded during SMW 40, while correspondent minimum populations (0.6 & 1.2 individuals per plant) was found during SMW28 in RA. The peak population of thrips was observed at RA during 30th SMW as (4.9 & 8.9 individuals per plant), respectively at Bt and non-Bt genotypes, declined to the lowest level of (0.1 & 0.3 individuals) in 41st SMW for both genotypes. Bt-cotton harbored relatively lower population of B. tabaci and T. tabaci in both fields owning to the presence of physico-morphich plant characters. A negative correlation of B. tabaci population was found with a maximum temperature and rainfall, and a positive relation with humidity. T. tabaci had a positive correlation with temperature and rainfall, and a negative correlation with relative humidity. The current research concluded that weather factors play and important role to increase or decrease the populations of sucking insect pests of cotton.

scholarly journals Population dynamics of exotic rugose spiralling whitefly, Aleurodicus rugioperculatus Martin (Hemiptera: Aleyrodidae) on coconut as influenced by weather factors and natural enemies

2020 ◽  
pp. 120-125
Author(s):  
K. Elango ◽  
S. Jeyarajan Nelson
Keyword(s):  
Population Dynamics ◽  
Negative Correlation ◽  
Natural Enemies ◽  
Tamil Nadu ◽  
Abiotic Factors ◽  
Climatic Conditions ◽  
Weekly Interval ◽  
Maximum Temperature ◽  
Weather Factors ◽  
Extent Of Damage

The rugose spiralling whitefly, Aleurodicus rugioperculatus Martin is a new exotic pest occurring in several crops including coconut since 2016 in India. Due to variation in the agro-climatic conditions of different regions, arthropods show varying trends in their incidence also in nature and extent of damage to the crop. Besides, abiotic factors also play a key role in determining the incidence and dominance of a particular pest and their natural enemies in a crop ecosystem. The population dynamics of new exotic whitefly species, A. rugioperculatus and their associated natural enemies was assessed on five-year-old Chowghat Orange Dwarf coconut trees at Coconut Farm of Tamil Nadu Agricultural University. The study indicated that RSW was found throughout the year on coconut and the observation recorded on weekly interval basis shows that A. rugioperculatus population escalated from the first week of July 2018 (130.8 nymphs/leaf/frond) reaching the maximum during the first week of October (161.0 nymphs/leaf/frond) which subsequently dwindled to a minimum during April. The parasitisation by E. guadeloupae on RSW ranged from 31.60 percent in Aug. 2018 to 57.60 percent in December 2018. The association of biotic and abiotic factors with A. rugioperculatus population showed a negative correlation with E. guadeloupae and C. montrouzieri. There was a significant positive correlation between maximum temperature and minimum temperature as well as relative humidity. However, rainfall showed a negative correlation with A. rugioperculatus population.

scholarly journals Incidence forecasting of new invasive pest of coconut rugose spiraling whitefly (Aleurodicus rugioperculatus) in India using ARIMAX analysis

2021 ◽  
Vol 23 (2) ◽  
pp. 194-199
Author(s):  
K.ELANGO ◽  
S. JEYARAJAN NELSON ◽  
P.DINESHKUMAR
Keyword(s):  
Tamil Nadu ◽  
Prediction Models ◽  
Time Series Data ◽  
Management Strategies ◽  
Climatic Conditions ◽  
Invasive Pest ◽  
Series Data ◽  
Maximum Temperature ◽  
Weather Factors ◽  
Extent Of Damage

The rugose spiraling whitefly (RSW), Aleurodicus rugioperculatus Martin is a new invasive pest occurring in several crops including coconut since 2016 in India from Tamil Nadu, Karnataka, Kerala and Andhra Pradesh. The population dynamics of new invasive whitefly species, A. rugioperculatus study indicated that RSW was found throughout the year on coconut and the observation recorded on weekly interval basis shows that A. rugioperculatus population escalated from the first week of July 2018 (130.8 nymph/ leaf/ frond) reaching the maximum during the first week of October (161.0 nymph/ leaf/ frond) which subsequently dwindled to a minimum during April. Due to variation in the agro-climatic conditions of different regions, arthropods show varying trends in their incidence also in nature and extent of damage to the crop. Influence of weather parameters on rugose spiralling whitefly incidence is lacking, which is essential for developing management strategies. The forecasting model to predict rugose spiralling whitefly incidence in coconut was developed by ARIMAX model of weekly cases and weather factors. In exploring different prediction models by fitting covariates to the time series data, ARIMA (0,2,1) with Maximum temperature was found best model for predicting the rugose  spiralling whitefly incidence and all covariates were found non-significant predictors except maximum temperature.

scholarly journals Seasonal Incidence and Effect of Abiotic Factors on Population Dynamics of Sucking Insect Pest Complex of Groundnut

2021 ◽  
pp. 10-17
Author(s):  
K. Shamili Dhatri ◽  
M. S. V. Chalam ◽  
A. Rajesh ◽  
B. Ramana Murthy ◽  
N. C. Venkateswartlu
Keyword(s):  
Negative Correlation ◽  
Minimum Temperature ◽  
Significant Positive Correlation ◽  
Insect Pests ◽  
Abiotic Factors ◽  
Insect Pest ◽  
Significant Negative Correlation ◽  
Maximum Temperature ◽  
Seasonal Incidence ◽  
Positive Correlation

Studies on seasonal incidence of sucking insect pests carried out with three dates of sowing viz., early (July 15th), normal (July 30th) and late (August 15th) revealed that the incidence of leafhoppers, aphids and thrips started from 5 to 14 DAS (days after sowing) and continued till harvesting. In early sown crop, the incidence of leafhoppers started from 31 SW and incidence of aphids and thrips started from 30 SW and continued up to 42 and 43 SW for leafhoppers and aphids, respectively and 41 SW for thrips. In normal sown crop, incidence of leafhoppers and aphids started from 32 SW and incidence of thrips started from 31 SW and continued till the end of 45 SW for all the three pests. In late sown crop, the incidence of leafhoppers started from 35 SW and incidence of aphids and thrips started from 34 SW and continued up to 46 and 47 SW for leafhoppers and aphids, respectively and 46 SW for thrips. Correlation studies revealed that incidence of leafhoppers exhibited significant negative correlation with maximum temperature (r = -0.467, -0.442 and -0.464) and rainfall (r = -0.518, -0.529 and -0.742) during all the three dates of sowing (early, normal and late, respectively) and significant negative correlation with minimum temperature in late sown crop (r = -0.448). Aphids exhibited significant negative correlation with maximum temperature (r = -0.469, -0.521 and -0.472) and rainfall (r = -0.443, -0.450 and  -0.721) in all the three dates of sowing (early, normal and late, respectively) while significant negative correlation with minimum temperature in early and late sown crop with r values -0.519 and -0.324.  Thrips exhibited significant positive correlation with maximum temperature (r = 0.522, 0.459 and 0.447), significant negative correlation with rainfall (r = -0.458, -0.465 and -0.451) during three dates of sowing (early, normal and late, respectively) while significant negative correlation with relative humidity in early sown crop (r = -0.616) and significant positive correlation with minimum temperature in early sown crop (r = 0.463).

scholarly journals Key Traits and Promising Germplasm for an Organic Participatory Tomato Breeding Program in the U.S. Midwest

HortScience ◽  
2015 ◽  
Vol 50 (9) ◽  
pp. 1301-1308 ◽  
Author(s):  
Lori Hoagland ◽  
John Navazio ◽  
Jared Zystro ◽  
Ian Kaplan ◽  
Jose Gomez Vargas ◽  
...  
Keyword(s):  
Plant Traits ◽  
Insect Pests ◽  
Farming Systems ◽  
Field Trials ◽  
Climatic Conditions ◽  
Breeding Program ◽  
F1 Hybrids ◽  
Participatory Plant Breeding ◽  
Organic Management ◽  
The U.S

Local production of organic tomatoes marketed directly to consumers is growing rapidly in the U.S. Midwest. Growers serving this market need cultivars that are well adapted to local climatic conditions, are competitive under organic management, and have end-use quality characteristics desired by their customers. Participatory plant breeding is a powerful, cost-effective approach with potential to engage growers in development of new cultivars optimally adapted to organic farming systems. To initiate a participatory breeding program for organic tomatoes an online grower survey was conducted to identify key plant traits, and a diverse set of tomato germplasm was evaluated under organic management to better understand horticultural constraints and identify adapted germplasm for further development. Tomato growers rated flavor as their top breeding priority, followed by disease resistance with late blight (LB) (Phytophthora infestans), early blight (EB) (Alternaria solani), and septoria leaf spot (SLS) (Septoria lycopersici) identified as the most problematic diseases. In field trials, foliar diseases were problematic in both years, though many entries exhibited partial resistance. Differences among entries in resistance to insect pests such as hornworms (Manduca sexta) were also observed. Yield varied widely among entries with some of the F1 hybrids and heirloom cultivars performing well despite significant disease pressure. Overall, we identified existing cultivars and F1 hybrids with potential to meet the immediate needs of Midwest organic tomato growers, and segregating breeding populations for further selection to be conducted on working organic farms.

Effect of Weather Factors on the Variability of Economic Characteristics in Sunflower Hybrids

2019 ◽  
pp. 70-84
Keyword(s):  
Climate Change ◽  
Climatic Conditions ◽  
Economic Traits ◽  
Weather Factors

This article presents the results of twelve-year trials of the Region and Ryabota simple hybrids and the three-line hybrid Kameniar breeding laboratory of IOC NAANU hybrid labs, and analyzes their adaptation to ongoing climate change. The purpose of our work was to determine the formation of major economic traits in sunflower hybrids, depending on the agro-climatic conditions of the year.

scholarly journals Evaporative Cooling Options for Building Air-Conditioning: A Comprehensive Study for Climatic Conditions of Multan (Pakistan)

Energies ◽  
2020 ◽  
Vol 13 (12) ◽  
pp. 3061 ◽  
Author(s):  
Shazia Noor ◽  
Hadeed Ashraf ◽  
Muhammad Sultan ◽  
Zahid Mahmood Khan
Keyword(s):  
Thermal Comfort ◽  
Co2 Emissions ◽  
Air Conditioning ◽  
Evaporative Cooling ◽  
Cooling Capacity ◽  
Climatic Conditions ◽  
Maximum Temperature ◽  
Human Thermal Comfort ◽  
Work Input ◽  
System Configurations

This study provides comprehensive details of evaporative cooling options for building air-conditioning (AC) in Multan (Pakistan). Standalone evaporative cooling and standalone vapor compression AC (VCAC) systems are commonly used in Pakistan. Therefore, seven AC system configurations comprising of direct evaporative cooling (DEC), indirect evaporative cooling (IEC), VCAC, and their possible combinations, are explored for the climatic conditions of Multan. The study aims to explore the optimum AC system configuration for the building AC from the viewpoints of cooling capacity, system performance, energy consumption, and CO2 emissions. A simulation model was designed in DesignBuilder and simulated using EnergyPlus in order to optimize the applicability of the proposed systems. The standalone VCAC and hybrid IEC-VCAC & IEC-DEC-VCAC system configurations could achieve the desired human thermal comfort. The standalone DEC resulted in a maximum COP of 4.5, whereas, it was 2.1 in case of the hybrid IEC-DEC-VCAC system. The hybrid IEC-DEC-VCAC system achieved maximum temperature gradient (21 °C) and relatively less CO2 emissions as compared to standalone VCAC. In addition, it provided maximum cooling capacity (184 kW for work input of 100 kW), which is 85% higher than the standalone DEC system. Furthermore, it achieved neutral to slightly cool human thermal comfort i.e., 0 to −1 predicted mean vote and 30% of predicted percentage dissatisfied. Thus, the study concludes the hybrid IEC-DEC-VCAC as an optimum configuration for building AC in Multan.

Mapping genetic variation and seed zones for Bromus carinatus in the Blue Mountains of eastern Oregon, USAIn this article, mention of companies or trade names does not constitute an endorsement of any product or procedure.

Botany ◽  
2010 ◽  
Vol 88 (8) ◽  
pp. 725-736 ◽  
Author(s):  
R. C. Johnson ◽  
Vicky J. Erickson ◽  
Nancy L. Mandel ◽  
J. Bradley St Clair ◽  
Kenneth W. Vance-Borland
Keyword(s):  
Environmental Variables ◽  
Regression Models ◽  
Plant Traits ◽  
Seed Source ◽  
Maximum Temperature ◽  
Blue Mountains ◽  
Seed Transfer ◽  
Bromus Carinatus ◽  
Seed Zones ◽  
Transfer Zones

Seed transfer zones ensure that germplasm selected for restoration is suitable and sustainable in diverse environments. In this study, seed zones were developed for mountain brome ( Bromus carinatus Hook. & Arn.) in the Blue Mountains of northeastern Oregon and adjoining Washington. Plants from 148 Blue Mountain seed source locations were evaluated in common-garden studies at two contrasting test sites. Data on phenology, morphology, and production were collected over two growing seasons. Plant traits varied significantly and were frequently correlated with annual precipitation and annual maximum temperature at seed source locations (P < 0.05). Plants from warmer locations generally had higher dry matter production, longer leaves, wider crowns, denser foliage, and greater plant height than those from cooler locations. Regression models of environmental variables with the first two principal components (PC 1 and PC 2) explained 46% and 40% of the total variation, respectively. Maps of PC 1 and PC 2 generally corresponded to elevation, temperature, and precipitation gradients. The regression models developed from PC 1 and PC 2 and environmental variables were used to map seed transfer zones. These maps will be useful in selecting mountain brome seed sources for habitat restoration in the Blue Mountains.

Seasonal Incidence of Major Sternorrhynchan Insect Pests Infesting Arecanut In South India

2021 ◽  
Vol 27 (1) ◽  
Author(s):  
Vinod Kumar Dubey ◽  
C.M. Kalleshwaraswamy ◽  
B.K. Shivanna
Keyword(s):  
South India ◽  
Field Experiments ◽  
Insect Pests ◽  
Transitional Zone ◽  
Maximum Temperature ◽  
Seasonal Incidence ◽  
Correlation Studies ◽  
Pseudococcus Longispinus ◽  
Sunshine Hours ◽  
Chrysomphalus Aonidum

Field experiments were conducted during 2019-20 to know the seasonal incidence of three species of sternorrhynchan insect pests infesting in arecanut viz., whitefly, Aleurocanthus arecae, armoured scale, Chrysomphalus aonidum and mealybug, Pseudococcus longispinus in two different locations under southern transitional zone. The study revealed that, all the three species infesting arecanut were active throughout the year. Correlation studies of whiteflies showed that, rainfall was significantly positively correlated and maximum temperature and sunshine hours were significantly negatively correlated. For armoured scales, non-significant positive correlation with minimum temperature and for the mealybug resulted that the maximum temperature was significantly positively correlated whereas the relative humidity was significantly negatively correlated.

scholarly journals The Role of Soil Amendments on Population Dynamics of Insect Pests, Growth Parameters and Yield of Eggplant, Solanum melongena (L.) Moench

2017 ◽  
Vol 7 (1) ◽  
pp. 7
Author(s):  
P. K. Baidoo ◽  
M. B. Mochiah ◽  
D. Asare ◽  
A. A. Sefah
Keyword(s):  
Soil Fertility ◽  
Plant Height ◽  
Bemisia Tabaci ◽  
Insect Pests ◽  
Soil Amendments ◽  
Aphis Gossypii ◽  
Solanum Melongena ◽  
Cow Dung ◽  
Leucinodes Orbonalis ◽  
Number Of Leaves

Loss of soil fertility as a result of continuous cropping on the same piece of land has necessitated the need to improve soil fertility for better crop yields. Inorganic and organic fertilizers have been used to improve soil fertility, however, excessive use of soil amendments improve vegetative growth of plants thereby attracting large numbers of insect pests. Cow dung and poultry droppings were used as soil amendments in a field experiment using eggplant Solanum melongena. The effects of these organic manures were compared with inorganic fertilizer (NPK) and a control where there was no application of soil amendment in a randomized complete block design with 3 replicates. Parameters studied were pests’ and their numbers, plant height, number of leaves per plant, leaf area, stem girth and yield. The major insect pests identified on the plant were Bemisia tabaci, Aphis gossypii, Leucinodes orbonalis and Eublemma olivacea. Bemisia tabaci and Aphis gossypii scores were significantly larger on cow dung and poultry manure plots. Leucinodes orbonalis and Eublemma olivacea numbers were not significantly different on the treated and control plots. Mean plant height, number of leaves and yield differed significantly among the soil amended plots. Even though soil amendments improve the nutrient content of the soil and the yield of crops it could lead to increase in pests numbers and damage caused to plants.

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