26 research outputs found
Evaluation of egg larval predator anthocorid bug Cardiastethus exiguus against Opinsina arenosella in Tamil Nadu
Impact of olfactory conditioned parasitoid Goniozus nephantidis in suppression of Opisina arenosella under field conditions in east coast of Andhra Pradesh
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Efficacy of Neem Formulations against Pink Mite, Acaphylla Thea Watt Infesting Tea in India
Digital phenotyping of coconut and morphological traits associated with eriophyid mite infestation
Observations were recorded on traits associated with mite infestation related at two stages of button on six different coconut cultivars over three years. Highly significant correlation was found between mite damage score with color or weight of tepal. Step-wise multiple regression of the data analysis showed color of inner tepal as major trait associated with infestation by eriophyid mite. Other traits are ratio of tepal weight to tepal area, per cent of buttons with pink discoloration or with resin, tepals of regular aestivation and gap between fruit and tepal. Digital phenotype data of 83 image files were used to calculate color signature and correlated the same to mite damage score over three years. Red spectral values were found to vary from 14 to 251, green values to 12 to 237 and blue to vary from 5 to 183. Spectral values red max, green max, 3* Red + Green max had high significant negative correlation (>-0.4) with mite damage. Color and firmness of fruits and tepals of three coconut varieties were further analyzed where, fruits and tepals of COD variety showed high red/green (a* value of Hunterlab) >12. Firmness of 3 month old tepal and fruit of Benualim (BGRT) tall variety was (penetrometer reading >38) higher than other varieties
A Sustainable Technique for Colony Multiplication by Eduction of Wild Nests of the Stingless Bee Tetragonula iridipennis Smith
Colony multiplication of stingless bees, Tetragonula iridipennis, largely relies on the eduction of wild colonies from their natural nesting sites in India. During the hiving of wild colonies, colonies were destroyed with the loss of robust wild foragers and built-in storage reserves over the years. The present study was conducted to devise a technique to sustainably multiply the colonies of stingless bees from the wild colony and the colony establishment and development during the eduction process. The annexure hives provided for eduction were accepted in a shorter time (3.25 ± 1.18 days), with the construction of storage pots observed at 7.75 ± 1.59 days after hive acceptance by the bees. The movement of foragers between the wild colony and the annexure hives was noticed for 13.80 ± 4.20 days. The foragers settled in the annexure hives and started foraging after 18.20 ± 2.49 days. The advancing fronts were observed at 26.67 ± 2.58 days after the addition of the laying queen in the established annexure hives. There was a significant increase in the number of inhive workers after the queen seeding in the annexure hives. This technique is the easiest and most sustainable non-
destructive way of multiplication of stingless bee colonies without loss in viability of the perennial wild colony
All India Co-ordinated Research Project on Biological Control of Crop Pests
Not AvailableSurveys were undertaken to document the fauna of insects, spiders and
entomopathogenic nematodesacross India despite the travel restrictions due to COVID-19.
The expeditions undertaken yielded several species of natural enemies viz.,Chalcididae
(66.32%), Eulophidae (19.94%), Pteromalidae (4.14%) and Encyrtidae (3.37%) of
Hymenoptera and 14 species of trichogrammatids representing 7 genera. The predominant
genera of hymenopteran insect parasitoids were identified as Dirhinus Dalman (30.47%)
followed by Brachymeria Westwood (27.73%), Hockeria Walker (22.27%) and
Antrocephalus Kirby (18.75%). Revisionary studies of the braconid parasitoid, Apanteles
sp. ater-group including subgroup eublemmae of the genus (Hymenoptera: Braconidae) of
the Oriental region was carried out with an illustrated key, in which a total of 97 species
were recorded and illustrated. Three species of tachinid flies, Peribaea orbata on larva of
Spodoptera litura, Halidaia luteicornis on larva of Parnara sp., Sturmiopsis inferens on
larva of Sesamia inferens and Carcelia sp. from the larvae of Helicoverpa armigera
(Noctuidae) were identified and described.
The spider fauna of rice ecosystem was documented, where six species of long jawed orb
weaver, Tetragnatha species have been described of which T. keyserlingi was the
predominant species across the surveyed locations in Tamil Nadu. The species,
Tetragnathanitens collected from Tamil Nadu and Telangana was the first report from
India. The spitting spider, Scytodes fusca Walckenaer of family Scyotidae was redescribed
with documentation of variations in the vulval pattern of the female and theory about the
introduction of this Pantropical species to India.Not Availabl
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Not AvailableGlobally, maize is an important cereal food crop with the highest production and productivity. Among the biotic constraints that limit the productivity of maize, the recent invasion of fall armyworm (FAW) in India is a concern. The first line of strategy available for FAW management is to evaluate and exploit resistant genotypes for inclusion in an IPM schedule. Screening for resistant maize genotypes against FAW is in its infancy in India, considering its recent occurrence in the country. The present work attempts to optimize screening techniques suited to Indian conditions, which involve the description of leaf damage rating (LDR) by comparing injury levels among maize genotypes and to validate the result obtained from the optimized screening technique by identification of lines potentially resistant to FAW under artificial infestation. Exposure to 20 neonate FAW larvae at the V 5 phenological stage coupled with the adoption of LDR on a 1–9 scale aided in preliminary characterize maize rize maize genotypes as potentially resistant, moderately resistant, and susceptible. The LDR varies with genotype, neonate counts, and days after infestation. The genotypes, viz., DMRE 63, DML-163-1, CML 71, CML 141, CML 337, CML 346, and wild ancestor Zea mays ssp. parviglumis recorded lower LDR ratings against FAW and can be exploited for resistance breeding in maize.ICAR-NAS
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Not AvailableConogethes punctiferalis Guenee is a polyphagous insect pest that is difficult to manage because it feeds within plant tissue. Management by mass trapping using semiochemicals, especially pheromones, represents a viable option to control such borers. Herein, pheromonal compounds were extracted from male and female moths and assessed using headspace sampling and electroantennogram response. One-d-old C. punctiferalis showed a higher response to volatile solvents than 4-d-old ones, irrespective of sex. The male antenna was found more sensitive than the female for volatile compounds. However, the female response to male headspace extract and abdominal tip extract was very high (i.e., 4.006 mV and 2.217 mV, respectively), which revealed the presence of males producing a female-attracting olfactory cue in C. punctiferalis. This was also confirmed by males calling the female before mating by extruding the hair pencils in their abdominal tip. The male pheromone extract when analyzed in gas chromatography–mass spectrometry indicated the presence of methyl acetophenone or 3-ethyl acetophenone.
Conogethes punctiferalis Guenee (Lepidoptera: Pyralidae) is a polyphagous pest that infests 30 crop plants belonging to 23 families (Thyagaraj et al. 2003). It is an important pest not only in South and South East Asia and Australia (Pena et al. 2002) but also as a newly introduced pest in Europe. Although its management is normally attained by the use of chemical pesticides (Renuka et al. 2002, Stanley et al. 2010, Regupathy and Ayyasamy 2014), proper management is achieved only by repeated applications of high concentrations because of the concealed nature of the larvae that feed within the plant tissues. Pest management using pheromones for mass trapping or mating disruption offers a viable alternative for such borers (Breth and Tee 2007). The use of a pheromone is more effective in detecting the infestation and, thus, determines timing of pesticide application (Cruz et al. 2012), leading to a reduction in insecticide usage.
The isolation, identification, and use of sex pheromones of C. punctiferalis have been previously reported. The pheromone component of C. punctiferalis was first reported by Konno et al. (1982) as (E)-10-hexadecenal. Traps containing 250 μg of C. punctiferalis pheromone were reported to significantly reduce the pest in citrus orchards in China (Cai and Mu 1993). The compounds were later identified as (E)-10-hexadecenal and (Z)-10-hexadecenal as the major compounds (Liu et al. 1994). But, the synthetic sex pheromone consisting of (E)-10-hexadecenol and (Z)-10-hexadecenal was not as effective as the crude pheromone extracts (Xiao and Honda 2010). Three compounds, (E)-10-hexadecenal (E10-16:Ald), (Z)-10-hexadecenal (Z10-16:Ald), and hexadecanal (16:Ald), were identified in the female gland extract of C. punctiferalis by Jung et al. (2000). Among the various combinations E10-16:Ald and Z10-16:Ald at 70:30 to 80:20 were the most attractive to males in wind tunnel experiments and field trapping experiments in orchards (Jung et al. 2000). The third compound 16:Ald did not show an electroantennogram (EAG) response in a Korean population but elicited response in the C. punctiferalis from China (Liu et al. 1994). Apparently, variation in sex pheromonal compositions appears to be far more widespread than previously thought and the composition differs from population to population. The sex pheromone attraction of the Korean population of C. punctiferalis varies with that of Chinese and Japanese populations (Boo and Park 2005). In India, E10:16Ald used in pheromone traps resulted in moth catches in castor fields but not in cardamom plantations (Chakravarthy et al. 2013). The (Z)-10 hexadecenol and 16-hexadecenal blend did not attract and trap any male moths (Chakravarthy et al. 2015). Thus, there is a need to isolate and identify the pheromone compound of the C. punctiferalis populations in India. Furthermore, a complex combination of the pheromone system of the C. punctiferalis consists of E10-16:Ald, Z10-16:Ald for long-range attraction and Z9-27:CH,Z3Z6Z9-23:CH for short-range attraction and final recognition of females by males (Xiao and Honda 2010, Chakravarthy et al. 2015). In addition, E-2-methyl-2-butenoic acid (tiglic acid), a compound extracted from the hair pencils of males, was reported to have a significant role in mate recognition, coupling, and mating success. The present study was designed to extract pheromones of both male and female C. punctiferalis by gland excision/solvent extraction and headspace extraction and to determine the biological activity, detect EAG response, and identify the active compounds by using gas chromatography–mass spectrometry (GC-MS) techniques.Not Availabl
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Not AvailableIn the present work, we took two nanomaterials (NMs), mesoporous silica nanoparticles (MSNs) and multiwalled carbon nanotubes (MWCNTs), and compared their in vivo toxicity taking albino mice as a test animal model. Presently, conflicting data persist regarding behavior of these NMs with macromolecules like protein and lipid at the cellular level in cell lines as well as in animal models and this generated the interest to study them. The mice were treated orally with a single dose of 50 ppm MWCNTs and intraperitoneally with 10, 25, and 50 mg kg-1 body weight (BW) of MSNs and 1.5, 2.0, and 2.5 mg kg-1 BW of MWCNTs. Liver enzyme markers serum aspartate aminotransferase (AST), alanine aminotransferase, and alkaline phosphatase along with total protein (TP) levels were evaluated 7 days postexposure. No significant differences in organ weight indices or enzyme levels were observed between different treatment doses but there were significant differences between the treatment groups and the controls. Of the three enzymes assayed, AST displayed a peculiar pattern, especially in the MWCNTs intraperitoneally treated group. TP level was significantly increased in the orally treated MWCNTs group. The results showed that MWCNTs even at much smaller doses than MSNs displayed similar toxicity levels, suggesting that toxicity of MWCNTs is greater than MSNsNot Availabl