Cheilomenes Sexmaculata Research Articles

Non-consumptive effects of the zigzag ladybird beetle, Cheilomenes sexmaculata (Fab.) on its prey, the cotton aphid, Aphis gossypii Glover

ABSTRACT Non-consumptive effects (NCEs) of predators include non-lethal changes in prey altering their behaviour and physiology with increased oxidative stress under predation-risk. Although prey species may exhibit a complex of antioxidant mechanisms, these may be inadequate to result in a reduction of adverse biological consequences in the prey. Reduced prey fitness may result and could contribute to enhancing biological control. Cotton aphid, Aphis gossypii is an important polyphagous pest predated by a variety of coccinellids and very much preferred by zigzag ladybird beetle, Cheilomenes sexmaculata (F.). Possible NCEs of C. sexmaculata on cotton aphid were studied to understand the underlying anti-oxidative mechanisms. We found that the non-consumptive effect is induced by olfactory cues, and even short-duration exposure could raise antioxidant enzyme levels in the cotton aphid. Aphids antioxidant mechanism uses upregulation of superoxide dismutase (SOD) and catalase (CAT) but not sufficiently to offset the oxidative damage that led to increased Malondialdehyde (MDA) content. Affected aphid biology with reduced reproductive performance as recorded 30.0 ± 4.40 nymphs/female under predation-risk compared to no-predation (41.6 ± 5.60). Further, the induction of winged morphs increased with active predation (21.53 ± 1.05%) and increased risk of predation (18.28 ± 4.86%) compared to aphids not exposed to predators (6.00 ± 2.99%). Antioxidant production costs were compensated by the exposed aphids directly through reduced reproduction and also triggered winged morphs in progeny. Non-consumptive effect might directly contribute to declines in aphid populations through reduced reproduction and may also stimulate dispersal of winged morphs.

<p><strong>Evaluation of insecticides against cotton mealybug, <em>Phenacoccus solenopsis</em> Tinsley and their safety to important predators</strong></p>

Cotton plays an important role in the world economy by supplying raw materials to different manufacturing units. Of late, it is being seriously attacked by the cotton mealybug, Phenacoccus solenopsis Tinsley. The biological control involving coccinellid beetles and chrysopids as predators could lead to ecologically sustainable mealybug control. Here, in the context of conservation of natural enemies, we exploredthe efficacy of insecticides on the cotton mealybug and also safety to other predators. Six insecticides viz; chlorpyrifos 20 EC (0.05%), endosulfan 35 EC (0.07%), monocrotophos 36 SL (0.04%), malathion 50 EC (0.12%), dichlorvos 76 EC (0.15%), and alphamethrin 10 EC (0.01%) were tested for their residual toxicity against the mealybug, P. solenopsis and its coccinellid predators. Studies revealed that, both chlorpyrifos and malathion showed highest toxicity in terms of mean mortality (100%) to female mealybugs at 24 h of exposure as against lowest in endosulfan (35%). Interestingly, chlorpyrifos and dichlorvos, which proved toxic to mealybug were less toxic to the grubs of Cryptolaemus montrouzieri, registering only 21.66 per cent and 34.16 per cent mortality, respectively. These insecticides when offered to the adults along with honey differed in toxicity as stomach poison at 24 hrs of exposure. Endosulfan registered mortality to the tune of 60 and 70% against Coccinella septempunctata and Cheilomenes sexmaculata, respectively. However, stomach toxicity pertaining to the insecticide-sprayed mealybugs as prey offered to all the three species of predators indicated that the insecticides, chlorpyrifos and endosulfan were lesser toxic to these wherein mean mortality ranged from 38.09 to 56.66 and 50 to 65.71%, respectively. Dichlorvos was the most toxic, registering 100% mortality for all 3 predators viz. Nephus regularis, Scymnus coccivora and Hyperaspis maindroni. The release of C. montrouzieri coupled with chlorpyrifos is likely to be a better option for the management of mealybugs infesting several agri-horticultural crops.

<p><strong>Spatial distribution and sequential sampling of aphid and their natural enemies on wheat</strong></p>

Although many pests attack wheat, the damage due to wheat aphids has been on rise due to climate change phenomenon. Population of aphids increases during February to March and so the ladybird beetles to devour on aphids. With the aim of facilitating conservation of ladybird beetles, predator conditioned sampling plans were worked out. Wheat aphids, Rhopalosiphum padi L. and Sitobion avenae F. were observed infesting wheat. Major predatory coccinellid beetles, Cheilomenes sexmaculata (Fabricius) and Coccinella septempunctata (Linnaeus) were also found feeding on the wheat aphids. Spatial distribution of mixed population of the aphids and coccinellid beetles was analyzed using variance-mean ratio and regression models such as Taylor’s power law and Iwao’s mean crowding regression. The aphids and its predatory beetles were counted at different crop age. The mean population for wheat aphid was 7.88/plant and 0.72/ plant at 75 and 106 days after sowing (DAS), respectively. Variance-mean ratio indicated regular to aggregated distribution of aphids on the crop. Taylor’s power law aggregation parameter (b = 2.62) and density contagiousness co-efficient (β = 1.20) of Iwao’s mean crowding regression also revealed aggregated distribution of the wheat aphids. The mean population of coccinellid beetles varied from 0.72 to 1.43/plant during 68 to 100 DAS. Taylor’s power law aggregation parameter (b = 3.64) and density contagiousness co-efficient (β = 2.09) of Iwao’s mean crowding regression revealed aggregated distribution of the predators on the wheat crop. Sequential sampling plans were developed for wheat aphid management with and without predator’s effect through Taylor’s power law and Iwao’s mean crowding regression. Inclusion of predator effect in the regression models increased aphid population levels which necessitates need for management measures at higher population levels. Thus, the sequential sampling plans with predator effect are useful in avoiding unnecessary pesticide application on wheat crop for the aphid management.

Performance of various colored sticky traps in monitoring against insects of maize crop

The field study on relative performance of various colored sticky traps against insects of maize crop (Zea mays L.) was conducted during 2019. Five different colored sticky traps i.e., yellow, blue, green, white and transparent were installed, where each trap was replicated four times. The field was divided into four blocks, each having a size of 30,000 square feet. In each block, five colored sticky traps were randomly installed at one feet above the crop height. Weekly observations were taken to count the number of insects attracted to various colored from germination till harvesting of crop. Identification of insects were done on available literature. Data of abiotic factors were also obtained to determine their influence on attractiveness of colored sticky traps for insects. During the study, five insect pests and one predator species were found i.e., Rhospalosipum maidis, Cicadulina mbila, Frankliniella occidentali, Atherigona soccata, Adelphocoris suturalis and Cheilomenes sexmaculata on various colored traps. All the insects were strongly attracted toward yellow colored traps as compere to others. The overall weekly observation showed that peak populations of R. maidis, F. occidentali, A. suturalis, C. sexmaculata were recorded on 31st March, 2019 on various colored traps. The maximum population of C. mbila and A. soccata was recorded on 6th April and 5th May, respectively. The populations of R. maidis, Cicadulina mbila, F. occidentali and C. sexmaculata showed positive and significant. Weakly a-biotic factors significantly affected on the performance of colored sticky traps to attract various insect. Based on the findings, yellow colored traps should be used for the early detection and monitoring of maize insects. Key words: Maize insects; performance; Sticky traps http://dx.doi.org/10.19045/bspab.2021.100038

On the Reproductive Diapause in the Predatory Ladybird Cheilomenes sexmaculata (Fabricius, 1781) (Coleoptera, Coccinellidae)

The ability to enter reproductive diapause was experimentally studied in females of the laboratory population of the predatory ladybird Cheilomenes sexmaculata originated from individuals collected in Nepal in a region of subtropical monsoon climate. The experiment included 12 regimes, i.e. combinations of 2 temperatures (20 and 24°C), 3 photoperiods (day lengths of 10, 12, and 14 h), and 2 diets (the green peach aphid Myzus persicae and eggs of the grain moth Sitotroga cerealella). Females with undeveloped ovaries and well developed fat body were considered as diapausing. The proportion of diapausing females was significantly dependent only on the temperature being 0.8% at 24°С and 7.4% at 20°С. Although found in only a small fraction of the studied population, the ability to enter reproductive diapause (as suggested by literature data) was probably an important prerequisite for Ch. sexmaculata spread northwards to the temperate zone.

Feeding potential and foraging behaviour of Cheilomenes sexmaculata (F.) on the cotton aphid, Aphis gossypii glover

Feeding potential and foraging behaviour are two important factors which determine the predator’s efficiency of managing prey. Predator-prey system of Cheilomenes sexmaculata (Fabricius) and Aphis gossypii Glover was evaluated to find out the predation efficiency. Feeding potential was observed for different stages of C. sexmaculatus on A. gossypii whereas, functional and numerical responses were ascertained as a function of prey/host density. For the grub stage, highest feeding potential (101.43 ± 3.04 aphids) was observed for the fourth instar which was higher than the gross feeding potential of all other instars. Among the adults, female recorded high feeding potential with a mean daily consumption of 43.13 ± 0.54 aphids. Life table studies showed intrinsic rate of increase (r) of 0.22 with the mean generation time of 27.29 days. The foraging behaviour studies revealed that all the grub stages and adults displayed a type-II functional response. The IV instar grub has shown the lowest handling time with highest maximum predation (96.1aphids/day), followed by female (94.6), male (82.6) and other stages. However, female depicted a rapid extinction of aphid by keeping it below 25, as against fourth instar grub and male which affected extinction by keeping it below 30. So, the releases of fourth instar grub and female of C. sexmaculatus could be advocated for the augmentative biological control of A. gossypii.

BIO-ECOLOGICAL STUDY OF FEW SPECIES OF APHIS LINN. IN NORTHEAST BIHAR AND THEIR ASSOCIATION WITH FOOD PLANTS AND NATURAL ENEMIES FOR POSSIBLE USE IN THE BIOLOGICAL CONTROL

Aphids are small, soft bodied, polyphagic and polymorphic sap sucking insects. During the extensive survey of different localities of 10 districts of northeast Bihar in different seasons, 41 species of aphids were recorded on more than 122 plant species belong to 35 families. Among these, only 09 species of Aphis viz., Aphis affinis Del Guercio, Aphis craccivora Koch, Aphis fabae Scopoli, Aphis glycine Matsumura, Aphis gossypii Glover, Aphis nasturtii Kaltenbach, Aphis nerii Boyer de Fonscolombe, Aphis puniceae Passerini and Aphis spiraecola Patch were recorded in the target area. The maximum number of plants were infested by A. gossypii (46 plants), followed by A. craccivora (36 plants), A. nasturtii (18 plants) and A. spiraecola (18 plants). Six species of coccinellids (Cheilomenes sexmaculata (Fabricius), Coccinella septempunctata Linnaeus, Coccinella transversalis Fabricius, Micraspis discolor (Fabricius), Pseudospidimerus circumflexa var. testaceus (Weise) and Scymnus pyrocheilus (Mulsant) and six species of syrphid predators (Allograpta javana (Wiedemann), Asarkina ericetorum (Fabricius), Episyrphus balteatus (DeGeer), Ischiodon scutellaris (Fabricius), Melanostoma orientale (Wiedemann) and Paragus serratus (Fabricius)) were recorded on Aphis spp. in the target area. Seven species of parasitoids viz, Aphelinus albipodus Fatima & Hayat, Aphelinus basilicas Fatima & Hayat, Aphelinus gossypii Timberlake, Aphelinus sp., Aphidius sp., Binodoxys indicus Subba Rao & Sharma and Lipolexis oregmae (=scutellaris) (Gahan) were also recorded on Aphis spp. in the target area. Six species of predators (C. sexmaculata, C. septempunctata, C. transversalis, E. balteatus, I. scutellaris and P. serratus) and three species of the parasitoids (A. gossypii, B. indicus and L. oregmae) were found abundantly on Aphis spp. in the target area and may be utilised in the biological control programme after further study

Maternal body size and age govern reproduction and offspring phenotype in the zig-zag ladybird beetle (Menochilus sexmaculatus)

Maternal effects are possible channels through which mothers provision their offspring differentially, thereby affecting offspring phenotype. We investigated maternal effects in the zig-zag ladybird beetle (Menochilus sexmaculatus (Fabricius, 1781) = Cheilomenes sexmaculata (Fabricius, 1781)) in response to body size (induced by different feeding regimes during larval development) and their age within the reproductive cycle. Different-sized females were permitted to mate and were provided with daily-replenished ad libitum prey. After mating, reproductive output and developmental duration of offspring from different oviposition days were recorded. We hypothesized that small females would lay smaller and fewer eggs than larger females, and that egg mass would also reduce with increased maternal age. In our study, the larger mothers laid more eggs per day. Small and large mothers oviposited maximally at middle age. Maternal age did not influence the egg mass, although it was slightly higher in the case of older, larger females. Offspring from old, small and large mothers developed rapidly. This nimble development could be an adaptive strategy for the use of ephemeral aphid patches. The results of the study are indicative of this ladybird species’ ability to adjust their offspring’s life-history traits, a feature more prominent in larger females.

Cheilomenes sexmaculata (Coccinellidae: Coleoptera) as a potential biocontrol agent for aphids based on age-stage, two-sex life table.

The Zigzag ladybird beetle, Cheilomenes sexmaculata (Fabricius) (Coleoptera: Coccinellidae), is a biological control agent that feeds on a variety of aphid species. Life table and predation data of C. sexmaculata were collected under laboratory conditions at 25±2⁰C, 60±5% RH and L14: D10 h in connection with feeding on four different aphid species; Lipaphis erysimi (Kaltenbach), Myzus persicae (Sulzer), Aphis nerii (Boyer de Fonscolombe) and Diuraphis noxia (Mordvilko). Larval development of C. sexmaculata was long when fed on M. persicae (12.18 days) and shorter on D. noxia (10.64 days). The male’s lifespan was longer on M. persicae (26.70 days) and shorter on L. erysimi (23.67 days). Fecundity was maximum when the beetle was fed D. noxia (316.8 eggs/female) and minimum on M. persicae (199.1 eggs/female). Net reproductive rate, intrinsic rate of increase and finite rate of increase were highest on D. noxia with values of 158.4 (offspring individual-1), 0.22 d-1, and 1.24 d-1, respectively whereas the respective parameters were lowest on L. erysimi (99.5 offspring individual-1, 0.19 d-1, and 1.20 d-1, respectively). However, the mean of the generation (T) was shorter on A. nerii (22.48 d-1) and longer on M. persicae (24.68 d-1). Based on life table parameters obtained under laboratory conditions, the most appropriate host of C. sexmaculata was D. noxia. This study should help us to improve mass rearing and use of C. sexmaculata in the biological control of aphids on field and horticultural crops.

Record of insect pests along with their natural enemies on chilli crop at Bilaspur

The experiment was carried out at horticultural research farm of BTC CARS, Bilaspur during Rabi 2019-20. Studies on insect pest complex of chilli along with their natural enemies revealed that thrips (Scirtothrips dorsalis), aphid, (Aphis gossypii), mite (Polyphagotarsonemus latus) and jassids (Amrasca bigutulla bigutulla) as sucking insect pest, while tobacco caterpillar (Spodoptera litura) as defoliator and fruit borer (Helicoverpa armigera) were observed as the major insect pests on chilli. The activity of aphid (0.51) was observed during fourth week of November (47th SMW) and the activity of jassids (0.40) were observed during second week of November (46th SMW) whereas, the activity of tobacco caterpillar (0.70) were observed during second week of January (2nd SMW) and the activity of fruit borer (0.30) were observed during second week of March (11th SMW). During all the stage of crop, the natural enemies viz., lady bird beetle (Cheilomenes sexmaculata, Coccinella transversalis, Coccinella septempunctata) and spider (Lynx spp.) were observed.

Seasonal Abundance of Spotted Pod Borer, Maruca vitrata Fabricius in Early Pigeonpea [Cajanus cajan (L.) Millsp.] and its Management through Farmscaping in Uttar Pradesh

Field experiments were carried out in pigeonpea during Kharif 2014 to Kharif 2017 for Maruca vitrata Fabricius management through farmscaping approach with 7 different border crops (5 leguminous crops; 2 non-leguminous crops) and a sole crop. The M. vitrata larval webbing per plant was lowest and per cent decrease in webbing/plant over sole crop was highest in sorghum (2.05 and 60.95) as border crop followed by pearl millet (3.29 and 37.39). The highest mean number of Coccinella septumpunctata per plant (0.77), Cheilomenes sexmaculata per plant (0.85/plant) and spiders (0.76/plant) was recorded from sorghum as border crop with pigeonpea. The highest percent increase in above said natural enemies over sole crop was also recorded from sorghum as border crop treatment (755.6, 844.4 and 660). The highest pigeonpea yield (730.72 kg/ha) and per cent yield gain (65.81%) was also recorded with sorghum treatment. Among 5 weather parameters tested, day length (1.53) and relative humidity (-0.12) were found to influence the M. vitrata population significantly and its incidence was recorded from 41st SMW to 47th SMW.

IDENTIFICACIÓN Y EVALUACIÓN DE LA INCIDENCIA DE INSECTOS Y HONGOS BENÉFICOS ASOCIADOS A Diaphorina citri KUWAYAMA (HEMIPTERA: LIVIIDAE) EN PLANTAS TRASPATIO (Citrus spp. y Murraya paniculata) DEL CANTÓN CATAMAYO (LOJA - ECUADOR)

En los últimos años, la citricultura mundial se ha encontrado amenazada por la presencia del psílido asiático de los cítricos, Diaphorina citri, un insecto perjudicial por ser portador de la bacteria “Candidatus Liberibacter asiaticus (las)”, causante de la enfermedad Huanglongbing (HLB), que ha provocado la devastación de plantaciones y la reducción de la producción de cítricos en todo el mundo. En el año 2017 se reportó la presencia de D. citri en plantas traspatio del cantón Catamayo, en la provincia de Loja, por lo que la presente investigación tuvo por objetivo identificar los enemigos naturales (depredadores, parasitoides y hongos) asociados a D. citri, y evaluar su incidencia en campo. Para ello, se realizaron muestreos en plantas traspatio (Citrus spp. y Murraya paniculata) del cantón Catamayo. Los muestreos se efectuaron a una altura de 1,5 m de las plantas en los cuatro puntos cardinales de la misma. Se colectaron larvas y adultos de depredadores, ninfas parasitadas y adultos de parasitoides, y adultos de D. citri para el aislamiento de hongos. Como resultado de la identificación en el laboratorio, se determinó la presencia de 11 especies depredadoras (principalmente Cheilomenes sexmaculata y Chrysopa spp.), dos especies de parasitoides (Diaphorencyrtus sp. y Tamarixia radiata) y cuatro especies de hongos (Cladosporium sp., Fusarium sp., Aspergillus sp. y Alternaria sp.). Diaphorencyrtus sp. tuvo una tasa de parasitismo del 7,76 %. Estas especies podrían utilizarse para establecer programas de control biológico, aprovechando su potencial como reguladores de poblaciones de ninfas de Diaphorina citri.

Preliminary study on screening of predatory coccinellids in agricultural field and analyzing the composition, diversity of predatory beetles in Davangere, Karnataka

A survey on the status of predatory coccinellids in various crop fields in Davangere, Karnataka is conducted to educate the farmers about the natural interaction of ladybird beetles and pests. In the present study, 288 individuals belonging to 7 Species, 2 sub-family of coccinellidae were recorded. Further, Cheilomenes sexmaculata was most dominant species which accounted for (35.06%) of total collected beetles, followed by Coccinella transversalis (20.83%), Chilocorus nigrita (18.40%), Bromoides suturalis (15.62%), Harmonia octomaculata (5.20%), Illeis cincta (3.12%) and Cocinella septempunctata (1.73%) respectively. Pests (aphids) and predator interactions was significantly (P < 0.05) evident in the various crop fields. This study also revealed good aggregation of ladybird beetles. Further detailed study is needed to understand the interaction with pest and insecticidal resistance analysis under natural conditions.

Cold tolerance and supercooling points of two ladybird beetles (Col.: Coccinellidae): Impact of the diet

Ladybird beetles have successfully been used to control different pests. Cheilomenes sexmaculata (Fabricius) and Oenopia conglobata contaminata)Menetries((Coleoptera: Coccinellidae) are two dominant and efficient predators of the common pistachio psylla, Agonoscena pistaciae (Hem.: Psyllidae) in Iran. In the current study, the impact of two diets, i.e., nymphs of A. pistaciae and eggs of Ephestia kuehniella Zeller (Lep.: Pyralidae), were investigated on the cold hardiness, supercooling point (SCP), and lethal temperature of different life stages of the coccinellids. The results suggested that the eggs of E. kuehniella are a suitable diet for both predators. In general, beetles of O. conglobata contaminata were more cold tolerant than those of C. sexmaculata. The SCP of the adults of C. sexmaculata, feeding on psyllid was about −15 °C, whereas the SCP of the beetles, feeding on the eggs of flour moth, was about −19 °C. However, the diets had no significant effects on the SCP of O. conglobata contaminata. For both ladybird beetles, eggs were the most sensitive stage, and adulthood was the most tolerant developmental stage. No eggs survived at zero and subzero temperatures. The survival of C. sexmaculata increased from 6.25% for adults fed on psyllids to 13.75% for those fed on flour moth eggs after 24 h exposure to cold at −4 °C. The survival of O. conglobata contaminata adults after exposure to cold at −4 °C for 24 h raised from 28.75% for adults fed on psyllids to 42.50% for those fed on flour moth eggs. Regardless of the diet, both beetles were considered to be chill-intolerant insects as the most mortality occurred above the SCP.

Susceptibility of immature stages of a biocontrol agent, Cheilomenes sexmaculata, to imidacloprid and pyriproxyfen

Chemical control is one of the important strategies in agricultural pest management because of easy operation, availability and fast control of pests. On the other hand, the environment has been exposed to various types of pesticides and pollutants which are growing daily. The persistent effects of residual pesticides commonly used cause numerous problems for non-target organisms especially parasitoids and predators. In this research, the effects of pyriproxyfen and imidacloprid on Cheilomenes sexmaculata (F.) (Coleoptera: Coccinellidae) were studied. The eggs of the ladybird beetle were treated with each pesticide in three concentrations by dipping method. Maximum field recommended concentration (MFRC=50 mg/L), 2/1 MFRC (to simulate multiple treatments) and 1/2 MFRC (to test the sublethal effects) were used for pyriproxyfen and 1/1 MFRC (140 mg/L), 1/2 MFRC (70 mg/L) and 1/4 MFRC (35 mg/L) were used for imidacloprid. The highest mortality of the first instar larvae was observed in imidacloprid at MFRC and pyriproxyfen at 2/1 MFRC. Also, maximum influence on fertility was observed at 2/1 MFRC of pyriproxyfen and MFRC of imidacloprid with 55% and 44% reduction compared to the control, respectively. Moreover, pyriproxyfen caused significant retardation on larval development at concentrations higher than 1/2 MFRC. Both insecticides initiated a significant effects on adult eclosion compared to the control and the greatest influence was observed by imidacloprid at 1/1 MFRC with 89% reduction in adult eclosion. Although results revealed that imidacloprid has higher acute toxicity to C. sexmaculata, further results obtained from the analysis of on the life cycle parameters of C. sexmaculata also indicated that pyriproxyfen also had toxic effects on this predator.

Intergenerational fluctuations in colour morph frequencies may maintain elytral polymorphisms in the ladybird beetle Cheilomenes sexmaculata (Coleoptera: Coccinellidae)

AbstractPhenotypic polymorphisms are found in a wide array of taxa, and unravelling the mechanisms that maintain them is of great interest to evolutionary and ecological biologists. Temporal environmental heterogeneity may play a role in the maintenance of polymorphisms but is poorly understood. In the present study, we analysed trends in intergenerational elytral colour morph frequencies in relation to changes in fitness and life history traits (i.e. body size, mortality, fecundity, hatching rate and mate preference) in the ladybird beetle Cheilomenes sexmaculata (Coleoptera: Coccinellidae). A long-term field survey spanning nine years showed that the frequency of dark morphs increases over winter and then decreases in spring. Dark morphs may have an advantage in winter due to their higher tolerance of low temperatures compared with light morphs. Light-morph females were heavier in winter than dark-morph females. They also mated more frequently and had higher hatching rates, potentially causing an increase in light morphs in spring. These results suggest that fluctuations in morph frequencies resulting from the conflicting directions of selection pressures between overwintering and spring generations may help to maintain genetic polymorphism.

Seasonal incidence and natural enemy complex of aphid, Aphis punicae Passerini (Hemiptera: Aphididae) infesting pomegranate in Kashmir

Survey on the pest incidence of pomegranate aphid ( Aphis punicae ) and natural enemies associated with it was conducted during 2016 at four locations each in district Srinagar and Baramulla. The studies revealed that that the highest mean population of aphids/shoot (33.99) was recorded in Srinagar, whereas, in Baramulla lower population of aphids/shoot (24.10) was recorded in comparison to Srinagar. Data further revealed that among different locations of Srinagar, highest average number of aphids/shoot (40.30) was observed at CITH and minimum (27.54) in Botakadal. Similarly, in district Baramulla highest mean number of aphids/shoot (27.63) was recorded at Sopore, whereas the lowest mean population (21.11/shoot) was observed at Dangerpora. The pest started its activity in I st week of April and reached to its peak in the 2 nd week of May in both the districts. Thereafter, the population of aphids declined gradually. The studies on natural enemies revealed that six coccinellid predators, viz., Coccinella septempunctata , Harmonia eucharis , Cheilomenes sexmaculata , Adalia tetraspilota , Hippodamia variegate and Calvia punctata and two syrphids viz, Sphaerophoria bengalensis and Episyrphus balteatus were found associated with pomegranate aphids. Among the natural enemies C. septempunctata was found to be the most dominant in both the districts. Overall, the abundance of natural enemies associated with pomegranate aphids in Baramulla was comparatively lesser than Srinagar.

Biodiversity of mealybugs, their host range and bio-control agents associated in different districts of Chhattisgarh plains

The survey of host range of mealybugs in five districts of Chhattisgarh plain regions namely Rajnandgaon, Balod, Dhamtari, Mahasamund and Raipur districts in which 132 plant species were observed. Among these, 72 plant species belonging to 28 families were identified as hosts out of which two species were of pulses (2.78%), one oilseed (1.39%), ten vegetables (13.89%), twelve fruits (16.67%), one fibre (1.39%), one sugarcane crop (1.39%), nineteen ornamentals (26.39%), fifteen medicinal (20.83%), two forest trees (2.78%) and nine plants under weeds (12.50%). The highest number of host plants of mealybugs were recorded in the family Malvaceae and Asteraceae followed by Fabaceae, Apocynaceae, Solanaceae, Rosaceae, Amaranthaceae and Lamiaceae. Among 72 plant species, 36 species of host plants were found having low infestation, 12 species had medium infestation and 24 plant species were observed to be highly infested by mealybugs. A total of eight mealybug species namely Ferrisia virgata Cockerell, Maconellicoccus hirsutus Green, Nipaecoccus viridis Newstead, Paracoccus marginatus Williams and Granara de Willink, Phenacoccus solenopsis Tinsley, Rastrococcus iceryoides Green and seven species of their natural enemies i.e., Cheilomenes sexmaculata, Brumoides suturalis, Scymnus sp., Chrysoperla sp., spiders as a general predator and Aenasius sp. and Pseudleptomastix mexicana as parasitoid were observed during the present studies. Among the Mealybugs species, P. solenopsis Tinsley was noticed as the most dominant species which observed on 14 species of different host plants infested with maximum 46.66 percent.

First Occurrence of Cheilomenes sexmaculata (Coleoptera: Coccinellidae) on the Caribbean Island of Curaçao.

The predatory ladybird species, Cheilomenes sexmaculata (Fabricius), is native to Asia and Australia but has established populations outside its native range, most recently on the eastern and northern coast of South America. Here, we report for the first time the identification of the introduced ladybird beetle, C. sexmaculata, to the Caribbean islands, specifically the island of Curaçao. Although C. sexmaculata is typically considered beneficial and used as a means of biological control in continental ecosystems, due to its high predatory and reproductive ability, it has the potential to cause major ecological impacts as an invader to sensitive Caribbean island ecosystems.

Influence of body size and familiarity on mating and reproductive parameters in the zig-zag ladybird beetle, Menochilus sexmaculatus (Coleoptera: Coccinellidae)

Body size often indicates an individual’s quality and so mate selection is typically for larger individuals, including in ladybirds (Coccinellidae). Many organisms including ladybirds are also are known to refuse mating attempts with familiar individuals, but whether at the expense of mating with larger individuals is not clear. We assessed the cumulative effect of body size and familiarity on mating and reproductive behaviour in the zig-zag ladybird beetle (Menochilus sexmaculatus (Fabricius, 1781) = Cheilomenes sexmaculata (Fabricius, 1781)). For this study, individuals were separated into small- and large-bodied individuals and allowed to mate in all possible combinations. Furthermore, following the first mating, an immediate second mating was provided to the males, with either a familiar (same as in the first mating) or an unfamiliar (new female with the same mating status) female. Mating and reproductive parameters were recorded. The mating duration was longer with familiar partners than unfamiliar individuals. Mating duration was shorter for the second mating, suggesting that mating and ejaculate transfer are costly, to assure higher reproductive success. In this ladybird beetle, familiarity modified mating duration, whereas fecundity and egg viability were influenced by body size.