P S Shera - PBG (original) (raw)

RESEARCH PUBLICATIONS by P S Shera - PBG

We investigated the suitability of six mealybug species, namely Phenacoccus solenopsis, Saccharic... more We investigated the suitability of six mealybug species, namely Phenacoccus solenopsis,
Saccharicoccus sacchari, Paracoccus marginatus, Drosicha mangiferae, Nipaecoccus viridis and
Ferrisia virgata as hosts to Aenasius arizonensis ( D Aenasius bambawalei). The study was
conducted to ascertain a viable parasitic relationship between a parasitoid species and
different mealybug hosts. Successful parasitization, complete development of immature stages
within the host and adult emergence was observed only in P. solenopsis, whereas, other
mealybug species were not found suitable as hosts by the parasitoid in both choice and nochoice
tests. The development studies of A. arizonensis on P. solenopsis showed that the mean
duration from oviposition to mummy formation was 6.13 days, while, from mummy formation
to adult emergence, it was 5.43 and 7.05 days for male and female, respectively. The total
development period from oviposition to adult emergence was 11.28 days for males and
13.13 days for females. Female adults (19.96 days) live longer as compared to male adults (7.83
days). Among different mealybug species, P. solenopsis was observed to be the only ecological
and fundamental host of A. arizonensis.

The toxicity of different insecticides was assessed against Aenasius arizonensis (Girault) (=Aena... more The toxicity of different insecticides was assessed against Aenasius arizonensis (Girault) (=Aenasius bambawalei Hayat) (Hymenoptera: Encyrtidae), a key endoparasitoid of Phenacoccus solenopsis Tinsley (Hemiptera: Pseudococcidae) on Bt cotton under semi-field conditions at the Entomological Research Farm, Punjab Agricultural University, Ludhiana during kharif, 2015. Eight insecticides , viz. profenophos 50 EC, thiodicarb 75 WP, buprofezin 25 EC, imidacloprid 17.8 SL, flonicamid 50 WG, spiromesifen 240 SC, diafenthiuron 50 WP and sulfoxaflor 24 SC were sprayed at recommended field doses on potted cotton plants having parasitized mealy-bugs (mummies). Based on the per cent reduction in adult emergence over control, spiromesifen (11.11 %), buprofezin (11.11 %) and flonicamid (12.11 %) were categorized as harmless; imidacloprid (28.28 %) as slightly harmful; diafenthiuron (55.56 %) and thiodicarb (70.70 %) as moderately harmful, whereas, profenophos (100.0 %) and sulfoxaflor (100.0 %) were highly toxic to the parasitoid. Insecticides like spiromesifen, buprofezin and flonicamid can be viable option for use in integrated pest management strategies against sucking insect pests in cotton ecosystem.

Lethal effects of eight insecticides at field dosages recommended in cotton crop were assessed ag... more Lethal effects of eight insecticides at field dosages recommended in cotton crop were assessed against Aenasius arizonensis (Girault) (Hymenoptera: Encyrtidae), a key endoparasi-toid of the mealybug Phenacoccus solenopsis Tinsley (Hemiptera: Pseudococcidae). Based on adult mortality, spiromesifen, buprofezin and flonicamid were categorized as slightly harmful, whereas, profenophos, sulfoxaflor, diafenthiuron, imidacloprid and thiodicarb were categorized as harmful insecticides according to the classification proposed by International Organization for Biological Control (IOBC). On exposure of mummies to insecticides, spirome-sifen, buprofezin and flonicamid were categorized as harmless, whereas, profenophos and sulfoxaflor were highly toxic on the basis of reduction in adult emergence. Afterward, adults of A. arizonensis emerged from mummies exposed to four insecticides (spiromesifen, flonica-mid, buprofezin and imidacloprid) were evaluated for sublethal effects in the subsequent generation. Spiromesifen and flonicamid caused the lowest reduction in parasitism rate of the parasitoid (harmless), while imidacloprid and buprofezin the most (slightly harmful). Imidacloprid significantly prolonged the development time and also reduced the longevity of A. arizonensis. However, buprofezin had no effect on development time of the parasitoid. All these four insecticides did not have any negative effect on the sex-ratio of A. arizonensis. Buprofezin, spiromesifen and flonicamid could facilitate biologically-based integrated pest management programs in cotton agroecosystem

Aenasius arizonensis (Girault) is an important solitary endoparasitoid of Phenacoccus solenopsis ... more Aenasius arizonensis (Girault) is an important solitary endoparasitoid of
Phenacoccus solenopsis Tinsley. To optimise the mass production of
high-quality females, it is important to assess the influence of mating
regimes on the progeny fitness and sex allocation. We, therefore,
hypothesise that mating combinations in A. arizonensis adults
emerged from different host instars may influence parasitism and sex
allocation in the subsequent generation. Therefore, we compared
three nymphal instars (1st, 2nd and 3rd) and adults host stages of
P. solenopsis for parasitism and sex allocation by A. arizonensis. Further,
F1 female progeny of the parasitoid emerged from different host
instars was henceforth evaluated for its fitness in six mating
combinations. A. arizonensis females parasitised all the host stages
except the 1st instar nymphs. The parasitised 2nd instar nymphs
yielded only males, while the sex ratio in the later host instars was
strongly female-biased. The parasitoid females preferred 3rd instar
nymphs with respect to higher parasitism (74.0–84.0%) and produced
more females in the F1 progeny as compared to other host stages. F1
females that emerged from 3rd instar nymphs produced significantly
higher parasitism (74.0–79.0%). These mating combinations also
yielded more female progeny in the F2 generation. However,
parasitism by F1 females was significantly lower (9.0–12.0%) when
mated with males that emerged from 2nd instar P. solenopsis nymphs.
Moreover, latter combinations yielded only male progeny in F2
generation. These findings can be used in laboratory mass rearing of
this parasitoid vis-à-vis biological control of P. solenopsis.

We investigated the influence of three nymphal instars (1st , 2nd and 3rd) and adult stages of Ph... more We investigated the influence of three nymphal instars (1st , 2nd and 3rd) and adult stages of Phenacoccus solenopsis Tinsley on the morphometric parameters of Aenasius arizonensis (Girault). The study was conducted to identify the suitable host stages for quality improvement in mass production of A. arizonensis for biocontrol program against P. solenopsis. The female parasitoid parasitized all the stages of P. solenopsis except 1 st instar nymphs, while the parasitism of 2 nd instar nymphs yielded only males in the progeny. The length and breadth of parasitoid mummies (pupae); body size, antenna length, the length of foreleg , middle-leg and hind-leg, and wing size of both male and female adults increased significantly with an advancement of host stage. The measurements through Scanning Electron Microscopy images also confirmed that the length of hind-leg increased with increase in host stage. The results of this study have implications for utilizing adult and 3 rd instar nymphal stages in mass production A. arizonensis for larger sized progeny and devising an effective biological control strategy against P. solenopsis.

Transgenic Bt cotton with genes from soil inhabiting spore forming bacterium Bacillus thuringiens... more Transgenic Bt cotton with genes from soil inhabiting spore forming bacterium Bacillus thuringiensis Berliner produces δ-endotoxin for the control of lepidopteran insects. The prey-mediated effects of Cry protein on the third trophic level is the most realistic exposure pathway that needs to be addressed as an important component of environment risk assessment. The green lacewing, Chrysoperla zastrowi sillemi (Esben-Petersen) (Neuroptera: Chrysopidae) is the most important generalist predator in the cotton ecosystem in India. The tri-trophic interactions involving Bt cotton expressing single (Cry1Ac) and dual toxins (Cry1Ac and Cry2Ab) fed herbivores, i.e. mealybug, Phenacoccus solenopsis Tinsley, whitefly Bemisia tabaci (Gennadius) and leafhopper, Amrasca biguttula biguttulla (Ishida) on the fitness of C. zastrowi sillemi, were studied. The development, survival and body weight of C. zastrowi sillemi had no deleterious effect as there were insignificant differences in any of the studied fitness parameters regardless of having consumed prey fed on Bollgard, Bollgard II and non-Bt cotton plants. The feeding potential of C. zastrowi sillemi on mealybug was also not different on Bt or non-Bt cotton plants. ELISA studies confirmed the presence of Cry proteins in Bt cotton leaves; however, no Cry1Ac or Cry2Ab protein was detected in prey herbivores (P. solenopsis, B. tabaci and A. biguttula biguttula) or in the predator C. zastrowi sillemi. It could be concluded that transgenic cotton that expresses single (Cry1Ac) or dual (Cry1Ac and Cry2Ab) toxins had no apparent effect on the fitness of the predator through its preys P. solenopsis, B. tabaci and A. biguttula biguttulla.

Aenasius arizonensis (Girault) (Hymenop-tera: Encyrtidae) is an important solitary endoparasitoid... more Aenasius arizonensis (Girault) (Hymenop-tera: Encyrtidae) is an important solitary endoparasitoid of mealybug, Phenacoccus solenopsis Tinsley (Hemiptera: Pseudococcidae). Studies on seasonal and biological interactions between host and parasitoid are important to optimize the mass production and field release of high-quality females. We investigated the influence of different crop seasons viz., pre-monsoon, monsoon and post-monsoon and host stages viz., three nymphal instars (1st, 2nd and 3rd) and adult stage of P. solenopsis on the development, longevity, fecundity and sex ratio of its parasitoid, A. arizonensis. A. arizonensis female parasitized all life stages of its host except the 1st instar nymphs. Only males emerged from parasitized 2nd instar nymphs, while the sex ratio in the later host instars was strongly female-biased. The adult host stage was most suitable for A. arizonensis in terms of shorter development time, while the 3rd instar nymphal stage was most suitable with respect to higher fecundity, proportion of adults emerged and more females in the progeny. Among different seasons, post-monsoon season (September–October) with temperature (25 to 29 °C) and relative humidity (68 to 73%) was most suitable for the overall fitness of the parasitoid. The findings of this study have implications in designing mass rearing of this par-asitoid and devising an effective biological control strategy for P. solenopsis on cotton.

Papers by P S Shera - PBG

Egyptian Journal of Biological Pest Control, Dec 5, 2023

CRC Press eBooks, Jan 31, 2023

International journal of pest management, Mar 29, 2024

International Journal of Tropical Insect Science

Agricultural Research Journal

Indian Journal of Entomology

Fall Army worm Spodoptera frugiperda (J E Smith) is a devastating, polyphagous pest which entered... more Fall Army worm Spodoptera frugiperda (J E Smith) is a devastating, polyphagous pest which entered India during 2018, starting from Karnataka and spreading to other states. This study on its native parasitoids and their parasitisation efficiency in maize crop under Punjab conditions. The S. frugiperda larvae were collected during kharif 2019 and 2020, and it was found that no parasitoids could be observed in 2019, as the pest recently invaded the crop in late season. But, during kharif 2020, two types of parasitoids were observed - Campoletis sp. (Hymenoptera: Ichneumonidae) and Chelonus formosanus Sonan (Hymenoptera: Braconidae); these which existed as natural enemies of Chilo partellus were found to adapt effectively with the new invasive pest. The parasitism rate of 21.92 and 16.33% was observed for the Campoletis sp. and Chelonus formosanus, respectively.

International Journal of Tropical Insect Science

Tomato (Lycopersicon esculentum Mill; Solanaceae) is one of the major horticultural crops cultiva... more Tomato (Lycopersicon esculentum Mill; Solanaceae) is one of the major horticultural crops cultivated in India. In order to ensure year-round availability of tomatoes, farmers are shifting to protected cultivation practices. Although the name ‘protected cultivation’ suggests freedom from biotic as well as abiotic hindrances in crop cultivation, incidence of pests have been reported in crops grown under polyhouses. This causes net house cultivators to use more chemical insecticides. Thus, an environmentally safe and economical method, comprising sticky traps, was evaluated for the management of sucking pests of tomato grown under protected conditions. Sticky traps of different shapes (rectangle, circle and triangle) and colours (yellow, blue and silver) were evaluated against sucking pests of tomato in 2018. The sticky trap, which found most efficient during 2018, was installed at different rates (2, 4 and 6 traps/250 m2) in the year 2019. Among the various sticky traps evaluated, yellow colour and rectangular trap proved best among the other shapes and colours against the aphids and whiteflies infesting tomato under protected conditions. On standardization of yellow-rectangular trap in 2019, a rate of installation of 4, 6 and 2, 4, 6 traps per 250 m2 were effective in reducing the population of aphids and whiteflies, respectively. Hence it could be concluded that yellow-rectangular sticky trap installed at a rate of 4 per 250 m2 proved effective against sucking pests of tomato grown under protected conditions.

Rice is essentially crop of warm and humid environment conducive to survival and proliferation of... more Rice is essentially crop of warm and humid environment conducive to survival and proliferation of many insect pests. More than 100 species of insects have been reported to ravage the rice crop, of these 15-20 are considered to be economically important (Heong and Hardy, 2009). The overall losses due to insect damage in rice have been estimated to be 25 % (Dhaliwal et al., 2010). Among sucking insect pests, brown planthopper (BPH), Nilaparvata lugens (Stål) (Homoptera: Delphacidae) and whitebacked planthopper (WBPH), Sogatella furcifera (Horvath) (Homoptera: Delphacidae) are the most economically important on rice crop (Singh et al. 2002). Severe attack causes, “hopper burn” symptoms in the field (Horgan, 2009). Farmers mostly rely on insecticides for their management. However, indiscriminate use of insecticides has led to many problems like elimination of natural predators, environmental pollution (Balakrishna and Satyanarayana, 2013), resistance and resurgence (Krishnaiah et al., 2...

The Indian Forester, 2003

Journal of Cotton Research and Development, 2012

Egyptian Journal of Biological Pest Control, Dec 5, 2023

CRC Press eBooks, Jan 31, 2023

International journal of pest management, Mar 29, 2024

International Journal of Tropical Insect Science

Agricultural Research Journal

Indian Journal of Entomology

International Journal of Tropical Insect Science

The Indian Forester, 2003

Journal of Cotton Research and Development, 2012

The performance of pyriproxyfen 10 EC applied @ 75, 100 and 125 g a.i. ha−1 against sucking insec... more The performance of pyriproxyfen 10 EC applied @ 75, 100 and 125 g a.i. ha−1 against sucking insect pests and predatory complex in four different experiments at farmers’ field on Bt cotton in comparison with untreated control and standard checks, i.e., diafenthiuron 50 WP @ 300 g a.i. ha−1 and ethion 50 EC @ 1000 g a.i. ha−1 for white fly and imidacloprid 17.8 SL @ 25 g a.i. ha−1 as well as acetamiprid 20 SP @ 20 g a.i. ha−1 for jassid, is reported. Based on pooled mean of two years, the per cent reduction of white fly adults over control in pyriproxyfen 10 EC @ 100 and 125 g a.i. ha−1 was at par with ethion 50 EC at 7 and 10 days after spray (DAS) but was significantly inferior as compared to standard checks at 3 DAS. However, all the three pyriproxyfen dosages were significantly more effective against nymphal population of white fly at 1, 3 and 7 DAS as against standard checks. After 7 days of spray, the per cent reduction in white fly nymphs over control in pyriproxyfen 10 EC @ 10...

Pest Management and Economic Zoology, 2009

India has one of the largest area among rice growing countries. Due to warm, humid environment, r... more India has one of the largest area among rice growing countries. Due to warm, humid environment, rice becomes prone to attack by planthappens of different types, which do a lot of damage to the rice crop. Management of these plant-hoppers is a must to avoid crop loss. To control damage by plant-hoppers it is important to know about the nature and symptom of damage, crop stage when the plant-hoppers attack, growing of resistant varieties in different rice growing areas. There are other methods also to be used simultaneously to control damage by the plant-hoppers.

Indian Journal of Plant Protection, 2014

Cartap hydrochloride (Mortar 75 SG) was evaluated @ 375, 425 and 500 g/ha for the control of stem... more Cartap hydrochloride (Mortar 75 SG) was evaluated @ 375, 425 and 500 g/ha for the control of stem borers and leaf folder under irrigated field conditions on rice during 2010 and basmati rice during 2011 and 2012 cropping seasons along with chlorpyriphos 20 EC @ 2500 ml/ha as standard check and untreated control. Mortar 75SG @ 425 and 500 g/ha provided effective control of stem borers (dead hearts and white ears) as well as leaffolder infesting rice/basmati rice and was statistically at par with chlorpyriphos 20 EC but significantly better than untreated control. The cost benefit ratio was highest in Mortar 75SG @ 425 g/ha followed by its higher dose @ 500 g/ha, chlorpyriphos 20 EC and Mortar 75SG @ 375 g/ha. Keeping in view the highest cost benefit ratio, Mortar 75SG @ 425 g/ha is recommended for management of stem borers and leaf folder on rice/basmati rice.

Pest Management and Economic Zoology, 2004

Biocontrol Science and Technology, 2017

Aenasius arizonensis (Girault) is an important solitary endoparasitoid of Phenacoccus solenopsis ... more Aenasius arizonensis (Girault) is an important solitary endoparasitoid of Phenacoccus solenopsis Tinsley. To optimise the mass production of high-quality females, it is important to assess the influence of mating regimes on the progeny fitness and sex allocation. We, therefore, hypothesise that mating combinations in A. arizonensis adults emerged from different host instars may influence parasitism and sex allocation in the subsequent generation. Therefore, we compared three nymphal instars (1st, 2nd and 3rd) and adults host stages of P. solenopsis for parasitism and sex allocation by A. arizonensis. Further, F 1 female progeny of the parasitoid emerged from different host instars was henceforth evaluated for its fitness in six mating combinations. A. arizonensis females parasitised all the host stages except the 1st instar nymphs. The parasitised 2nd instar nymphs yielded only males, while the sex ratio in the later host instars was strongly female-biased. The parasitoid females preferred 3rd instar nymphs with respect to higher parasitism (74.0-84.0%) and produced more females in the F 1 progeny as compared to other host stages. F 1 females that emerged from 3rd instar nymphs produced significantly higher parasitism (74.0-79.0%). These mating combinations also yielded more female progeny in the F 2 generation. However, parasitism by F 1 females was significantly lower (9.0-12.0%) when mated with males that emerged from 2nd instar P. solenopsis nymphs. Moreover, latter combinations yielded only male progeny in F 2 generation. These findings can be used in laboratory mass rearing of this parasitoid vis-à-vis biological control of P. solenopsis.