Vector-Virus-Plant Interactions
Insect Chemical Ecology
28
Scopus Publications
Scopus Publications
Preference shifts in Bemisia tabaci (Aleyrodidae: Hemiptera) after the acquisition of Mungbean Yellow Mosaic Virus from Vigna radiata D Rajabaskar, R Ranjithkumar, G Karthikeyan Plant Science Today, 2025 The silver leaf whitefly, Bemisia tabaci (Aleyrodidae: Hemiptera), is a polyphagous pest and a major vector of plant viruses, causing significant economic losses globally. It exhibits a complex of cryptic species and is known to transmit various plant viruses affecting numerous crops globally. A study was conducted in Tamil Nadu, India, to identify the dominant cryptic species of B. tabaci on legume crops, leading to the establishment of laboratory colonies of the most common types. The research focused on the feeding preferences of these whiteflies on healthy green gram plants (Vigna radiata (L.) R. Wilczek) versus those infected with the Mungbean Yellow Mosaic Virus (MYMV). Biochemical changes in MYMV-infected green gram plants, compared to healthy ones, were analysed to understand their influence on whitefly feeding preference. The cryptic species Asia II 8 was found to be the most common in legume crops. The study assessed whether these whiteflies favoured healthy green gram plants or those infected with MYMV. Our findings revealed that when healthy whiteflies acquired the virus from the host, their preference shifted toward healthy plants. This shift is linked to the biochemical changes associated with the infection status of the host. Following viral infection, there was a decrease in total sugars and chlorophyll, while levels of protein, phenol, peroxidase, and polyphenol peroxidase increased. These results suggest that the virus modifies the vector's behaviour through a shared host, enhancing the pathogen's ability to disseminate within the ecosystem.
Effect of elevated carbon dioxide on the fitness traits of Plutella xylostella (L.) (Lepidoptera: Plutellidae) K Haripriya, John Kennedy, V. Geethalakshmi, D. Rajabaskar International Journal of Pest Management, 2024 The life history and fitness parameters of diamondback moth, Plutella xylostella, were studied under ambient (410 ppm) and elevated concentrations (460, 510, 560, and 610 ppm) of carbon dioxide in a Soil–Plant–Atmosphere–Research chamber. The results revealed that the egg and larval durations were significantly longer at 410 ppm and shortened at a higher carbon dioxide concentration of 610 ppm. At elevated concentrations of 560 and 610 ppm, the net reproductive rate (R0) increased to 99.90 and 88.00 numbers per female in a lifetime, respectively. The intrinsic rate of increased (rm) value was 0.22 per day at 410 ppm; it increased linearly to 0.24, 0.26, 0.30, and 0.31 per day at 460, 510, 560, and 610 ppm, respectively. The fecundity rate increased from 150.86 ± 19.32 eggs (410 ppm) to 196.33 ± 8.63 eggs (560 ppm) on increasing carbon dioxide concentration but decreased to 171.46 ± 6.79 eggs at 610 ppm. These results suggest improved fitness of P. xylostella in the future scenario of global climate change with increasing carbon dioxide concentrations.
Impact of Watermelon bud necrosis virus (WBNV) infected plants on the volatile emission pattern in cowpea plants P. Arunkumar, J.S. Kennedy, D. Rajabaskar, P. Aishwarya Journal of Applied and Natural Science, 2022 Pathogens, including tospoviruses, are known to manipulate the behaviour of vectors after virus acquisition by plants to enhance virus transmission. Furthermore, as recently proven in the maize chlorotic mottle virus pathosystem, the vector's choice for virus-infected plants can change to a preference for noninfected plants after virus uptake by the vector. A similar trend was observed in the cowpea - Watermelon Bud Necrosis Virus (WBNV) - Thrips palmi (Karny) pathosystem. Similarly, in the no-choice bioassay, viruliferous T.palmi (carrying WBNV) settled preferentially more on healthy cowpea plants (56%) compared to virus-infected plants (47.3%), whereas non-viruliferous T.palmi settled preferentially more on WBNV infected (58.67%) cowpea plants compared to healthy plants (44%). The changes in preference of thrips towards host plants before and after virus acquisition may be due to the change of volatile cues. This study looked at the headspace volatile composition of healthy and WBNV-infected cowpea plants that attract thrips. Furthermore, the volatile analysis revealed that 1, 2-Propanediamine (0.62%) and Tuaminoheptane (0.55%) from healthy cowpea plants, as well as Tetradecane (0.35%) from WBNV-infected cowpea plants, both have a higher area percent than other volatiles. The amine (53%) and hydrocarbon (69%) groups of volatile organic compounds make up the majority of host volatiles found in healthy and virus-infected plants. The increased contact rates of viruliferous and non-viruliferous T.palmi towards healthy and WBNV-infected host plants could enhance virus transmission if thrips feed on them and acquire the pathogen prior to dispersal and the recorded host volatiles might be useful in vector management in future.
Blackgram CO 7: A new high yielding and bold seeded variety suitable for Tamil Nadu P. Jayamani, A. Muthuswamy, D. Kumaresan, T. Latha, D. Rajabaskar, M. Senthivelu, S. A. Fanish, S. Geetha Electronic Journal of Plant Breeding, 2022 Blackgram (Vigna mungo L.) is an important pulse crop in Tamil Nadu. An inter subspecific cross was made VBN (Bg) 5 x V. mungo var. silvestris (22/10) to develop high yielding variety with yellow mosaic disease resistance. A high yielding blackgram culture (COBG 10-05) was identified and evaluated in different yield trials from 2012 to 2020. The culture matures in 60 65 days. It recorded an overall mean yield of 881 kg/ha which is 12.1 , 12.4 and 14.4 per cent yield increase over the check varieties viz., CO 6 (786 kg/ha) , VBN 6 (784 kg/ha) and VBN 8 (770 kg/ ha), respectively. This culture is resistant to mungbean yellow mosaic virus disease and moderately resistant to leaf crinkle and stem necrosis diseases. It has bold seeds with 100 seed weight ranged from 5.5 to 6.0 g. The plant type is determinate with synchronized maturity and suitable for single/mechanical harvest. It contains 22.3 per cent protein. This culture was released as Co 7 and it is recommended for cultivation during kharif and rabi seasons in Tamil Nadu.
Elevated carbon dioxide influences the fitness of myzus persicae sulzer in cauliflower F Miriam Amala Saleesha, J S Kennedy, D Rajabaskar, V Geethalakshmi Indian Journal of Entomology, 2021 This study evaluated the effects of carbon dioxide (CO2) on the fitness of the aphid Myzus persicae Sulzer in cauliflower. The results revealed that the lifespan of 19 days (at 410 ppm) got shortened to 18 days at elevated CO2 (610 ppm). The nymphal duration decreased with increased CO2. The fertility/ female/ day worked out to 2.58 at 410 ppm, which increased to 3.72 at 610 ppm. The gross and net reproductive rates, intrinsic and finite rate of increase all rose under elevated CO2. The generation time and population doubling time at 410 ppm decreased at 610 ppm. Such an increased fertility and population in short time would have a direct effect on outbreak of the aphid in cauliflower.
Influence of elevated temperature on the fitness of Diamondback moth, Plutella xylostella (L.) in cauliflower K. Haripriya, , J.S. Kennedy, V. Geethalakshmi, D. Rajabaskar, , , and Journal of Environmental Biology, 2021 Aim: To understand the effect of elevated temperature on the bionomics and fitness parameters of Plutella xylostella which would help in predicting the population growth rates and formulating appropriate management tactics. Methodology: In the present investigation, the fitness parameters of diamondback moth were studied at six different temperatures (31, 32, 33, 34, 35 and 36°C) in cauliflower in Open Top Chambers. Observations were recorded on the survival, longevity and fecundity at daily interval. The raw data on bionomics and life table parameters were analyzed using TWO-SEX- MS chart. Results: The total life cycle of P. xylostella was longer at 31°C and it declined with increasing temperatures. However, P. xylostella did not complete its development at 35 and 36 °C. The intrinsic rate of increase (rm) increased from 0.22 at 31°C to 0.28 at elevated temperature of 34°C. Temperature also had a significant effect on the net reproductive rate (R0), Gross Reproductive Rate (GRR) and finite rate of increase (λ). Interpretation: The fitness parameters will help to predict the change that occur in P. xylostella population due to climate change and global warming.
A high yielding pigeonpea variety CRG 2012-25 as CO 9 released for Southern Zone of India A.Thanga Hemavathy J. R. Kannan Bapu, A.Thanga Hemavathy, D. Malarvizhi, P. Jayamani, K. Ganesamurthy, et al. Electronic Journal of Plant Breeding, 2021 A long duration high yielding Pigeonpea culture CRG 2012-25 as CO 9 was developed at the Department of Pulses, Centre for Plant Breeding and Genetics, Tamil Nadu Agricultural University, Coimbatore was released by Central Variety Release Committee during 2019. It is a cross derivative of CO 6 x IC 525427 with a suitable for kharif sowing. This variety yields on an average yield of 1700 kg/ha which is 17.58, 19.00 and 14.61 per cent yield increase over CO 6 (Local check), WRP 1 (Zonal check) and ICP 8863 (national check), respectively. It recorded maximum yield of 2697 kg/ha in Tandur, Telangana. This variety has bold seeds(100 seed weight of 9.0 - 10.0 g) with a protein content of 23.65 per cent. It is moderately resistant to wilt and SMD diseases and the pests viz., Maruca and pod fly. This variety is suitable for the southern zone of India which includes Tamil Nadu, Karnataka, Telengana, Andhra Pradesh and Odisha.
Melon thrips Thrips Palmi karny association with bud necrosis disease in water melon D Rajabaskar, I Rabeena, P Aishwarya, G Karthikeyan, T R Usharani, J S Kennedy Indian Journal of Entomology, 2020 Survey was conducted in Watermelon bud necrosis virus (WBNV) hotspot regions in Tamil Nadu and Karnataka to identify the predominant thrips species exist in those areas. The mean population of thrips was ranged from 0.35 to 1.64 no. / shoot and mean WBNV incidences were ranged from 25 to 56% in different regions. A phylogenetic relationship of thrips sample collected from 29 locations of WBNV hotspot regions showed that Thrips palmi Karny was the predominant species and the DNA sequence analysis matched with more than 99% similarity.
An integrated approach for identification of frankliniella schultzei (Trybom) I Rabeena, C Chinnaiah, G Karthikeyan, T R Usharani, N Balakrishnan, J S Kennedy, D Rajabaskar Indian Journal of Entomology, 2020 The blossom thrips Frankliniella schultzei (Trybom) (Thysanoptera: Thripidae) is a vector of tospoviruses and cause severe yield loss in several horticultural and agricultural crops. A study was conducted to identify the thrips species associated with GBNV (groundnut bud necrosis virus) hotspot regions of tomato in Tamil Nadu and Karnataka states using taxonomic, SEM and molecular diagnosis. Morphological distinguishing characters of F. shultzei include: eight segmented antennae, head with three pairs of ocellar setae, veins of forewing presenting continuous and equally spaced setae, five and two pairs of pronotal and metanotal setae, and absence of comb at eighth abdominal segment. The SEM analysis confirmed these and the PCR amplification showed 99% similarity with F. schultzei. It is concluded that F. schultzei was associated in all the GBNV hotspot regions.
Bioefficacy and phytotoxicity of Prempt 20EC against Chilli thrips, Scirtothrips dorsalis and fruit borer, Spodoptera litura on Chilli Pestology, 2006
Bioefficacy and phytotoxicity of prempt 20EC against pests of bhendi Pestology, 2006
Harvest time residues of profenofos (curacron 50EC) applied for management of shoot and capsule borer (conogethes punctiferalis guen.) in Cardamom Pestology, 2004
Bioefficacy of lambda cyhalothrin (Karate® 5 EC) against tea mosquito bug (helopeltis antonii sign.) on cashew Pestology, 2004
Field efficacy of lambda cyhalothrin (karate® 5 EC) against berry borer (hypothenemus hampei ferrari) in coffee Pestology, 2004
Harvest time residues of a new insecticide lambda cyhalothrin (Karate® 5 EC) in/on cashew Pestology, 2004
Persistence and dissipation of propiconazole (Tilt 25EC) in/on chillies Pestology, 2004
Field evaluation of lambda cyhalothrin (Karate® 5 EC) for control of shoot tip caterpillar (hypatima haligramma meyr.) on cashew Pestology, 2004
Harvest time residues of lambda cyhalothrin (Karate® 5 EC) applied to coffee Pestology, 2003
