<div style="text-align: justify;">Bemisia tabaci (Gennadius) is widely distributed polyphagous pest, found in tropical, subtropical and temperate regions. The overall impact of whitefly has been very devastating with yield losses ranging from 20 to 100 percent, depending upon the crop, season and prevalence of the whitefly. Although excessive and injudicious use of insecticides have led to increase in resistance level of white fly but still insecticides are considered as important tool for control of this pest. The bio-efficacy of emerging chemicals including insect growth regulators and neonicotinoids against whitefly has been evaluated in different studies. These studies have reported both lethal and sub lethal effects of various insecticides on white fly. The insecticides alter physiological mechanisms in whitefly leading to pronounced changes in physiological system, affecting the reproduction and overall development. These bioassays could be helpful in enlisting various new chemicals that would be helpful in management of this pest.</div>

Lethal and sublethal effects of insecticides on whitefly, Bemisia tabaci (Gennadius)- A review

<div>Background: Whitefly is one of the most destructive sucking pest in the tropical and subtropical regions of the world and causing significant crop losses directly by sucking sap from the plants and indirectly through the transmission of viral diseases specifically caused by the genus Begomovirus. The Begomovirus species viz., Mungbean yellow mosaic India virus (MYMIV) and Mungbean yellow mosaic virus (MYMV) are causing yellow mosaic virus disease in soybean, which is transmitted by whiteflies. The disease accounts to 30-70 per cent yield loss and increases up to 80 - 100 per cent during severe incidence. Hence, there is a need for development of integrated pest management strategies against disease and whiteflies, for this the knowledge on virus-vector relationship is required. But, the studies on biological relationship of yellow mosaic virus disease and whitefly in soybean are scarce. At this juncture, considering the importance of disease in soybean, the present investigation was carried out to know the virus -vector relationship of the YMV and whitefly in soybean. 
 
Methods: The experiment on virus-vector relationship of yellow mosaic virus and whitefly in soybean was conducted at Department of Entomology, College of Agriculture, G. B. Pant University of Agriculture and Technology, Pantnagar, Uttarakhand during 2016-17. The data on number of whiteflies per plant, acquisition and inoculation access feeding period and pre and post starvation period required for effective transmission of virus was recorded. 
 
Result: A single viruliferous whitefly was able to transmit virus and ten viruliferous whiteflies per plant were required for cent per cent transmission of virus. The minimum acquisition access and inoculation access feeding periods required for virus transmission was 0.25h (15 min) each; while the 100 per cent virus transmission was recorded with acquisition and inoculation period of 12h, each. The per cent transmission was increased with the increase of acquisition and inoculation periods. The rate of transmission was positively correlated with pre-acquisition starvation period and negatively correlated with post- acquisition starvation period.</div>

<div>Virus Vector Relationship of Yellow Mosaic Virus and Whitefly, Bemisia tabaci (Gennadius) in Soybean</div>

Background: Yellow mosaic disease (YMD), caused by the Mungbean yellow mosaic India virus (MYMIV), seriously affects soybean production in the central and northern regions of India. 
 
Methods: The present investigation was conducted to reveal the relation among the fluctuating population of whiteflies, YMD progression, meteorological parameters and crop age in four varieties, i.e. 335, JS 20-34, NRC 86 and MACS 1520, at J.N.K.V.V., Jabalpur, during kharif 2021 (June to September). The whitefly population, by visual and cage and YMD severity were recorded at weekly intervals.&nbsp; 
 
Result: Whiteflies first appeared 13 days after sowing (27th SMW) and reached a peak of 7.73 per plant (cage) and 3.29 per trifoliate (visual) at 29th SMW (July, 16-22). During this maximum and minimum temperature, morning and evening RH were 33.4 and 25.4&deg;C, 84.10 and 70.0 %, respectively. Whiteflies on JS 335 (0.639* and 0.635*) and MACS 1520 (0.672* and 0.639*) significantly positively correlated with maximum temperature in visual and cage counts. Wind speed exhibited a significant negative relation with a whitefly count of JS 335 (-0.753*) and MACS 1520 (-0.764*). YMD initiated (28th SMW) at high temperature (max 33.3&deg;C and min 25.1&deg;C), low rainfall (33.2 mm), less humid conditions (evening 58.3-morning 85.1 %) and presence of whitefly. In contrast, at the time of maximum disease progression (32nd SMW), comparative low temperature (max 28.5 and min 24.2&deg;C) and high humid conditions (evening 79.0-morning 90.0) prevailed. Among the four varieties, maximum disease severity was recorded in JS 20-34 (48.16%). The corresponding week&rsquo;s maximum temp (0.771**) and sunshine hours (0.792**) were negatively significant and evening RH (0.717*) and wind speed (0.708*) had a positively significant relation with mean YMD progression. A similar significant association was also obtained between the previous week&cent;s parameters and disease. YMD and whitefly exhibited a negative, non-significant association. Crop age also linked non-significantly with YMD progression. The present findings could be utilized to predict vector and YMD and to formulate appropriate management strategies for both.

Relationship between Whiteflies, Yellow Mosaic Severity, Weather and Crop Age in Soybean

Background: Yellow mosaic disease (YMD), continues to be a major production constraint in mungbean, especially under changing climatic conditions. Vector population dynamics, weather variability and sowing time play a decisive role in YMD epidemic development. The investigation aimed to elucidate the impact of fluctuations in whitefly population, interacting weather parameters and variation in sowing dates on YMD incidence and seed yield and management of the disease through chemical approach. 
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Methods: A field experiment was conducted during summer 2022-23 at MARS, Dharwad using susceptible mungbean variety DGGV 2 in Randomized Complete Block Design with three replications. The management experiment was laid out in Randomized Complete Block Design during summer 2023 and 2024 with 10 treatments and 3 replications. Weather data was recorded weekly and whitefly population was monitored on selected trifoliate leaves of five plants per replication. YMD incidence was assessed from 25 DAS across four sowing dates (30 Jan, 8 Feb, 14 Feb, 23 Feb). Correlation and regression analyses using SPSS and R were used to determine the influence of weather variables on whitefly dynamics and disease incidence. 
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Result: Whitefly population peaked (6.60/three leaves) in the 14th SMW under hot, dry conditions. Rainfall negatively influenced whitefly abundance (r = -0.807), while maximum temperature showed a positive association (r = 0.665). Early sowing on 30th&nbsp;January resulted in the lowest YMD incidence (13.85%) and highest yield (575.56 kg/ha), whereas delayed sowings recorded higher disease and lower yields. Seed treatment with Imidacloprid 60 FS 5 ml/ kg of seeds followed by foliar spray with Thiamethaxom 25% WG 0.3 g/L at 25 days after sowing reduced the yellow disease incidence and severity. Hence early sowing aligned with low vector activity and prophylactic spray of chemicals results in effective management of the disease.

Unravelling Whitefly Population Dynamics and Management of Yellow Mosaic Disease in Mungbean

Background: Blackgram (Vigna mungo L.), commonly known as urdbean in India, belongs to the Leguminosae family. Yellow mosaic disease (YMD) caused by Mungbean Yellow Mosaic Virus (MYMV) stands out as the most serious disease and a significant bottleneck for blackgram cultivation and production. Henceforth, an attempt was made to know the effective insecticide for the management of whiteflies transmitting YMD in blackgram. 
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Methods: The field experiment was conducted on management of whiteflies vectoring YMD of blackgram by using different combination of insecticides during kharif 2023 at College of Agriculture, Vijayapur, UAS, Dharwad by using randomized complete block design (RCBD). 
&nbsp; 
Result: Seed treatment with imidacloprid 600 FS @ 5 ml/kg seed + foliar spray of (pyriproxifen 5% + difenthuron 25% SE) @ 2 ml/l achieved the highest reduction of whitefly population over control of&nbsp;83.63,&nbsp;91.05&nbsp;and&nbsp;94.10 per cent&nbsp;at 30 DAS, 45 DAS and 60 DAS, respectively. It also resulted in the lowest disease incidence of&nbsp;13.42,&nbsp;17.55,&nbsp;20.80 and&nbsp;24.78 per cent&nbsp;at 30 DAS, 45 DAS, 60 DAS and 90 DAS (physiological maturity), respectively. Additionally, it produced the maximum yield of 7.87 q/ha&nbsp;with the highest B: C ratio of&nbsp;2.89. 
&nbsp;

Efficacy of Insecticides in the Management of Whiteflies, Vector of Blackgram Yellow Mosaic Disease

<div>Background: Pulse crops have a unique position in sustainable crop production as they provide highly nutritive food and keep the soil alive as well as productive. They play an important role in the Indian agriculture economy being the major source of protein in Indian dietary. Due to its more luxurious growth and more vegetative canopy, number of insect pests and diseases attack from seedling to maturity stage especially sucking pests like whitefly (Bemisia tabaci Genn.), which is the vector of the drastic disease, yellow mosaic virus disease (YMD) and cause losses ranging from 30-80% per cent. 
 
Methods: The field experiment on the management of whitefly and yellow mosaic disease (YMD), was conducted by integrating different combination of insecticides and yellow sticky trap during Kharif, 2018 and 2019 at instructional farm of VBKVK, Udaipur. Seven treatments comprising of different combinations of seed treatments at the time of sowing, foliar spray at 30 and 45 DAG and yellow sticky traps were evaluated.&nbsp; 
 
Result: Among the different treatments, seed treatment with Imidacloprid 600 FS @ 5 ml/kg, first foliar spray of Diafenthuron 50 WP @ 0.1% and second foliar spray with Acetamiprid 20 SP @ 0.5 g/l at 30 and 45 DAS respectively + yellow sticky trap resulted in significantly less YMD incidence (18.91%) and the minimum mean whitefly population and highest seed yield of blackgram. The above treatment was followed by seed treatment with Imidacloprid 600 FS @ 5 ml/kg and two foliar spray of Acetamiprid 20 SP @ 0.5 g/l at 30 and 45 DAS + yellow sticky trap, which recorded 20.31% disease incidence of YMD and mean whitefly population of (3.77 and 1.44/plant, respectively after first and second spray) and black gram yield of 10.01 q/ha.&nbsp;</div>

Management of Whitefly, Bemisia tabaci (Genn.) and Yellow Mosaic Virus Disease Infesting Blackgram, Vigna mungo (Linn)

Background: Mungbean is the major&nbsp; pulse crop of India. Pulse constitute the major source of dietary protein; therefore, it has ability to fulfil required protein recommended dietary allowance for vegetarian population of India. Pulse crop attack more than 200 insect pests.&nbsp; 
 
Methods: Efficacy test of Botanicals and Insecticides viz., Kaner powder, Garlic extract, Azadirectin 1500 ppm, Dasparni Ark, flonicamid, thiamethoxam, Imidacloprid and Dimethoate against B. tabaci was conducted in mungbean during Kharif 2022-2023 at Students&rsquo; Instructional Farm, Acharya Narendra Deva University of Agriculture and Technology, Kumarganj, Ayodhya (UP), India under field conditions with nine treatements including control in three replication.&nbsp; 
 
Result: The results demonstrated that Thiamethoxam 25 WG (50 g a.i./ha) was the most effective insecticide among all treatments, with a significant population reduction above control, followed by Imidacloprid 70 WG (5ml/l). Among the botanicals, Azadirectin 1500 ppm (5 ml/l) was the most effective against whitefly infestation in mungbean and could be applied as an eco-friendly alternative to conventional pesticides for whitefly management.

Efficacy of Botanicals and Insecticides against Whitefly, Bemisia tabaci Gennadius (Homoptera; Aleyrodidae) in Mungbean

<div>Background: Scientific research will continue to search for the best methods to control the insect pests and at the same time reduce insecticide concentrations used. Using of nanoinsecticide formulations may be resolving this problem.&nbsp; 
 
Methods: In this work two types of formulations were used; nanoformulations and their conventional formulations. Three common insecticides were used against the silver whitefly, Bemisia tabaci; indoxacarb, spirotetramat and thiacloprid in tomato fields. The nanoparticle sizes were ranged between 210 and 290 nm. The loading capacities were 70.6, 71.2 and 69.1% for indoxacarb, spirotetramat and thiacloprid, respectively. The recommended field concentration for each insecticide was used. The concentrations of nanoformulations were one-fifth of conventional one.&nbsp; 
 
Result: The obtained results showed that indoxacarb was the most effective insecticide against the B. tabaci in tomato field with the both formulations (nano and conventional) followed by thiacloprid and spirotetramat. By using of nanoformulations, the percent of reduction after the third application were 97.7, 38.2 and 44.8%, for indoxacarb, spirotetramat and thiacloprid, respectively. While, the corresponding results with the conventional formulation were 97, 39.8 and 49.2%, respectively. The obtained results also, showed that there were no difference between the nano and conventional formulations. The per cent of B. tabaci reduction after the third application were 97.7 and 97.0; and 38.2 and 39.8; and 44.8 and 49.2% for nano and conventional indoxacarb, spirotetramat and thiacloprid, respectively. These results may be throw some light in the advantages of using nanoformulations compared with the conventional formulations.</div>

Role of Some Nanoformulations in Suppression of Silver Whitefly, Bemisia tabaci Population in Compared with Their Conventional Formulations in Tomato Fields

Background: Yellow Mosaic disease caused by Mungbean yellow mosaic virus (MYMV) is one of the most destructive biotic production constraints in blackgram, responsible for yield losses up to 100 per cent. It is transmitted by whitefly in persistent circulative manner. The host plant resistance has a great importance in MYMV resistance. Morphological and Biochemical characters play a key role in offering resistance to vector and MYMV in the resistant genotypes. 
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Methods: The Experiment was conducted under glass house conditions using ten blackgram genotypes showed differential reaction to yellow mosaic disease during preliminary field screening. Experiment was laid out completely randomized block deign, replicated thrice. 
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Result: The results revealed that among the selected genotypes, resistant genotypes (GBG-1 and VBN-7) was recorded the maximum leaf thickness, maximum trichome density with shortest trichome length, maximum total phenolics, total proteins and total amino acids than the remaining genotypes which contributes resistance behavior in the host. Hence it concluded morphological factors are found responsible for vector preference for feeding where as biochemical parameters are crucial for virus infection and multiplication. 
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Morphological and Biochemical Factors Associated with Blackgram Resistance to Whitefly, Bemisia tabaci and Yellow Mosaic Disease

<div style="text-align: justify;">Background: Mung bean is important pulse crop in India due to its nutritional value. Its grain contains protein, fat, carbohydrate, vitamin and minerals therefore human uses it in various ways in food. Mung bean crop cultivated in kharif, rabi and summer season in India. Various species of insect pests are infested to mung bean crop and cause very harmful effect to crop and farmer. These pests decrease productivity and quality of mung bean.&nbsp; Methods: Field experiment was carried out for the study of seasonal incidence of insect pests on RMG-62 variety of green gram during kharif season 2019. Mung bean was grown on a plot size of 25 m &times; 25m with 50 cm row to row and 20 cm plant to plant spacing. Randomly selected 20 plants from weekly interval to record population of insect pests. The population of jassid and whitefly was recorded by counting number of pests on 2 upper, 2 middle and 2 lower leaves of a plant whereas population of aphid was recorded by counting number of aphid on 10 cm twig/plant. Result: The mean population of aphid, jassid and whitefly were recorded. Incidence of aphid started during 33th standard week with 0.9 aphid/10cm twig/plant, jassid and whitefly started during 32th standard week with 0.3 jassid/6 leaves/plant and 2.1 whitefly/6 leaves/plant, respectively. Peak mean population of aphid, jassid and whitefly reached during 36th standard week with 10.2 aphid/10cm twig/plant, 10.1 jassid/6 leaves/plant and 14.1 whitefly/6 leaves/plant, respectively. Simultaneously six species of insect pests also infested green gram, these were Mylabris pustulata, Helicoverpa armigera, Trichoplusia ni., Lampides boeticus, Spoladea recurvalis and Diaphania indica. The population of aphid, jassid and whitefly positively correlated with temperature. Population of aphid and whitefly had positive correlation with humidity, whereas jassid population had positive correlation with minimum humidity and negative correlation with maximum and average humidity. All three pests expressed negative correlation with rainfall.&nbsp;</div>

<div style="text-align: justify;">Seasonal Incidence of Insect Pests on Mungbean (Vigna radiata) in Correlation with Meteorological data</div>