1. KAUTIR (Kerala Agricultural University Theses Information and Retrieval)
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Item Biology of Aceria sp. (Acari:ERIOPHYIDAE) in Amaranthus tricolor L.and its management(Department of Agricultural Entomology, College of Agriculture, Padannakkad, 2024-07-05) Krishna Keerthi, K P; Sreekumar,K MThe study entitled ‘Biology of Aceria sp. (Acari: Eriophyidae) in Amaranthus tricolor L. and its management’ was carried out at Department of Agricultural Entomology, College of Agriculture, Padannakkad and farmer’s field at Thaikkadappuram, Nileshwar during 2019 – 2023, with an objective to elucidate the biology and life cycle of Aceria sp. (Acari: Eriophyidae) and interpret the nature and extent of damage caused by Aceria sp. on Amaranthus tricolor L. and to develop its management strategy. The life cycle of Aceria sp. included egg, larva, first inactive stage, nymph, second inactive stage and adult. The developmental cycle lasted for an average of 11.83 days. Egg, larva, first inactive stage, nymph, second inactive stage and adult took an average of 2.94, 1.99, 1.11, 2.69, 1.09 and 4.89 days respectively and measured an average length of 46.78, 74.54, 117.58, 153.82, 189.46 and 229.37 µm respectively. The pre – oviposition and post – oviposition was recorded as an average of 1.80 and 2.92 days respectively. The major symptoms were stunted growth, leaf crinkling and malformation, petiole elongation and fibrous shoots. Population assessment during the early season (December to mid – February) showed a gradual increase in mean population of mites from 16 in December to 73.56 in February. The late cropping season (March to May) observed its highest population mean in May (174.44). Predatory mite population gradually decreased over time. The height of the plants reduced to an average 67.38 per cent and the petiole elongated to a mean of 184.72 per cent. Leaf area reduced to 18.08 cm2, in relation to healthy leaves (25.70 cm2). The stray population of amaranthus plants grown in and around the farmers’ fields and the backyards of their houses, served as off – season host for the mite. The mites were highly host – specific, as it was not sighted in any of the collateral as well as weeds collected from the infested area. Field evaluation of different botanicals and acaricides were conducted in farmer’s field in Thaikkadappuarm. A day after the first spray, no mites were seen in plots sprayed with acaricides. Fenpyroximate (T2) sprayed plots observed a significant reduction in average population in the third (0.223), fifth (2.557), seventh (6.000) and fourteenth (13.553) days after spray. The second application of treatments observed a variable result, in which spiromesifen was superior to the others in the third (1.443) and fourteenth days (11.890). On the fifth day, wettable sulphur (4.333) and on the seventh day, fenpyroximate (7.113) recorded the least population mean. The analysis of pesticide residue conducted on samples sprayed with spiromesifen and fenpyroximate, on the fifth, seventh and tenth days after spray, resulted in detection of fenpyroximate at the rate of 0.29 mg per kg, 0.30 mg per kg and 0.29 mg per kg, respectively. Spiromesifen residues were not detected in the analysis.Item Diversity of coccinellid beetles (Coleoptera: Coccinellidae) of northern Kerala(Department of agricultural entomology, college of agriculture , Padannakkad, 2023) Gokul Goutham; Vidya, C VCoccinellid beetles, commonly known as ladybirds or lady beetles, belong to the family Coccinellidae of order Coleoptera, are species rich and play a significant and multifaceted role in agriculture. Coccinellids are ecologically and morphologically diverse and exhibit a wide range of food habits spanning kingdoms and trophic levels. Most of the coccinellids are predaceous on various agricultural pests, whereas a few are phytophagous, and some are mycophagous. The research work on “Diversity of coccinellid beetles (Coleoptera: Coccinellidae) of northern Kerala” was undertaken in the Department of Agricultural Entomology, College of Agriculture, Padannakkad during 2021-2023 for the documentation of the species composition and estimation of diversity indices of coccinellid beetles in different agro-ecological zones of northern Kerala and to generate DNA barcodes and carry out molecular analysis of coccinellids associated with different cropping systems. Purposive surveys were conducted across four different agro-ecological zones, viz., coastal plain, midland laterites, foothill, and high hill, covering Kasaragod, Kannur, Kozhikode, and Wayanad districts. Different cropping systems, viz., rice, vegetables, fruits, and plantation crops were covered during the survey. A total of 27 species of coccinellids belonging to six tribes were recorded. Among these, three were phytophagous viz., Afidenta misera, Henosepilachna septima, and H. vigintioctopunctata and two were mycophagous viz., Illeis bielawskii and Illeis cincta and rest of 22 species were predacious in nature. Total number of coccinellid species recorded from rice, vegetables, plantation crops and fruits were seven, 18, 11 and eight, respectively. Among different agroecological zones, high hills recorded maximum number of coccinellids (20) followed by coastal plain (19), midland laterites (14) and foothills (10). Diversity indices to assess species richness, diversity, dominance and evenness were estimated. The most abundant coccinellid species was H. vigintioctopunctata, with a relative abundance of 29.86 per cent. The predominant predatory coccinellid was Cheilomenes sexmaculata (11.88%), followed by Coccinella transversalis (11.72%). Among various cropping systems the vegetable cropping system displayed highest species richness, while rice showed lowest richness. High hills showed the highest richness and least rich was foot hills. Species diversity was estimated in terms of Shannon-Wiener index (H) and the most diverse cropping system was plantation crops (1.96) and least diverse was rice (1.15) ecosystem. Among the agroecological zones, high hill (2.47) was the most diverse, and the foothill was the least diverse zone (1.91). Species dominance was studied by using Simpson’s index. The highest value of Simpson’s index was observed in rice (0.46) and lowest value in plantation crops (0.17). Among agroecological zones, coastal plain was least diverse with highest dominance value (0.21) and lowest dominance value was in midland laterites (0.11). Pielou's evenness index (J) estimated how evenly species are distributed in a community. The vegetable cropping system had the lowest species evenness (0.39) while the plantation crops had the highest (0.65). The species were more evenly distributed in midland laterites (0.75), while less evenly in coastal plains (0.42). Total genomic DNA was isolated and mitochondrial Cytochrome Oxidase 1 (CO1) locus was amplified using LCO1490 /HCO2198 primers. DNA sequencing was done by outsourcing. The forward and reverse COI sequences were trimmed using BioEdit Sequence Alignment Editor software and assembled using CAP3 sequence assembler. Molecular analysis of 20 sequences representing 17 species was done using MEGA11 software. Homology analysis of 14 DNA sequences, encompassing 13 distinct species using Nucleotide BLAST of NCBI revealed a substantial similarity of over 98 per cent when compared to sequences present in the NCBI database. Six sequences of four species showed less than 90 per cent similarity to other sequences in the NCBI database. Phylogenetic trees were constructed using MEGA11 software with the Maximum likelyhood method and a bootstrap value of 1000. The analysis incorporated 20 generated sequences in this study and 20 sequences (including Amphix laevigatus as outgroup) retrieved from the NCBI database. The tree formed two major clades, one includes I. cincta and all other species formed the second major clade. Within the second major clade, members of each tribe formed as separate clade except for S. sp. nr. posticalis. Twenty accessions of 17 species were submitted to NCBI and BOLD databasesItem Incidence and management of pests of rose Rosa spp.(Department of Agricultural Entomology, College of Agriculture , Vellayani, 2023-07-13) Aswathy S S.; Narayana, RRose is one of the most common commercial ornamental crops seen in every household garden. Rose cultivation is gaining popularity day by day. Pest and disease infestation is one of the major concerns in rose cultivation. In this present scenario, a thorough knowledge of the pests infesting rose and their management under Kerala conditions is essential for the successful cultivation of roses. In this context, the present study, entitled "Incidence and management of pests of rose, Rosa sp.," was conducted at the Department of Agricultural Entomology, College of Agriculture, Vellayani, during the period 2020–2022. The objectives of the study were to document the pests infesting Rosa spp., their nature of damage and symptoms, natural enemies associated with the pests and to develop effective management practices. The documentation was conducted at 20 locations of Thiruvananthapuram district viz., Amaravila, Anayara, Attingal, Balaramapuram, Chala, Chirayinkeezhu, Gowreesapattom, Karamana, Karikkakom, Kattakada, Nalanchira, Neyyatinkara, Panangode, Peyad, Sreekaryam, Thiruvallam, Uchakkada, Ulloor, Vellayani, and Vembayam. A total of 42 species of pests were recorded in which twenty four were sucking pests and eighteen were chewing pests. Sucking pests documented were black vine thrips (Retithrips syriacus (Mayet)), chilli thrips (Scirtothrips dorsalis Hood), grapevine thrips (Rhipiphorothrips cruentatus Hood), Rhipiphorothrips pulchellus Morgan, redbanded thrips (Selenothrips rubrocinctus (Giard)), gold-tipped tubular thrips (Haplothrips gowdeyi (Franklin)), Haplothrips ganglbaueri Schmutz, spider mite (Oligonychus biharensis (Hirst)), pea aphid (Aphis craccivora Koch), cotton aphid (Aphis gossypii (Glover)), egyptian fluted scale (Icerya aegyptiaca (Douglas)), seychelles scale (Icerya seychellarum (Westwood)), cottony cushion scale (Icerya purchasi Maskell), California red scale (Aonidiella aurantii (Maskell)), mealybug (Planococcus sp.), striped mealybug (Ferrisia virgata Cockerell), spiralling whitefly 100 (Aleurodicus dispersus Russell), whiteflies (Unidentified sp. 1, Unidentified sp. 2), and unidentified species of cow bug, planthoppers, flatid planthopper and spittle bug. The biting and chewing pests recorded were leaf twisting weevil (Apoderus sp.), flower beetle (Popillia complanata Newman, Gametis versicolor (Fabricius)), flea beetle (Luperomorpha vittatta Duvivier), leaf cutting bee (Megachile sp.), common hedge blue (Acytolepis puspa (Horsfield)), brown tussock moth (Olene mendosa Hubner), tussock moth (Arna bipunctapex Hampson), tobacco cutworm (Spodoptera litura (Fabricius)), and black looper (Hyposidra talaca (Walker)). Leaf rollers, hairy caterpillar, slug caterpillar, grass hoppers, ash weevil, bag worms and slug pests documented during the study. A total of thirteen species of natural enemies associated with pests of rose were identified. Six species of spiders, Oxyopes birmanicus Thorell, Oxyopes javanus Thorell, Oxyopes shwetha Tikader, Stenaelurillus sp., Camaricus formosus Thorell, and Thomisus sp., were identified, and they were the predominant predators in the rose ecosystem. This was followed by four species of coccinellids (Pseudaspidimerus trinotatus (Thunberg), Rodolia sp., Scymnus sp., and Sticholotidini beetle), two species of preying mantids, Odontomantis pulchra Olivier and Hestiasula brunneriana Saussure, and a neuropteran insect. Spiromesifen 22.9 % SC @ 96 g a.i. ha -1 was the best treatment recorded for R. syriacus and S. dorsalis with highest reduction of 94.90 % and 98.1 % respectively in thrips population at 7 DAS. At 14 DAS, spiromesifen 22.9 % SC @ 96 g a.i. ha -1 was significantly superior to dimethoate 30 % EC @ 400 g a.i. ha-1 in reducing the population of S. dorsalis, while the effect of both treatments were statistically on par for R. syriacus. Least effective treatment was HMO @ 25 mL L-1 for both thrips and was on par with the effect of talc based formulation of L. lecanii @ 20 g L-1. Spiromesifen 22.9 % SC @ 96 g a.i. ha -1 treated plants showed lowest leaf damage (18.86 %) for R. syriacus and lowest flower (6.29 %) and flower bud (6.21 %) damage for S. dorsalis and the effect was on par with dimethoate 30 % EC @ 400 g a.i. ha-1 at 14 DAS. Lowest reduction (10.67 %) in spider population was 101 recorded in talc based formulation of L. lecanii @ 20 g L-1 treated plants which was statistically on par with spiromesifen 22.9 % SC @ 96 g a.i. ha -1, untreated plants and HMO @ 25mL L-1 treated plants. Flubendiamide 39.35 % SC @ 48g a.i. ha -1 was the effective treatment recorded with significantly higher percentage reduction in population of O. mendosa at 14 DAS followed by malathion 50 % EC @ 500 g a.i. ha -1 (85.91 %). Results of effect of different treatments on extent of leaf damage in O. mendosa infested plants showed lowest value in flubendiamide 39.35 % SC @ 48 g a.i. ha -1 treated plants and was on par with malathion 50 % EC @ 48 g a.i. ha -1. HMO @ 25mL L-1 was least effective in managing O. mendosa with mean percentage damage of 34.44. Lowest percentage reduction (8.33) in spider population was recorded in talc based formulation B. bassiana @ 20 g L-1 treated plants and was on par with untreated plants and NSKE 5%. A total of 42 species of pests infesting rose were recorded of which five are new records in rose from Kerala. Thirteen species of natural enemies associated with pests of rose were also recorded. Spiromesifen 22.9% SC @ 96 g a.i. ha -1 was the effective treatment for the management of S. dorsalis and R. syriacus and flubendiamide 39.35 % SC @ 48 g a.i. ha -1 was found effective in reducing Olene mendosa population in rose. 102Item Entomopathogenic nematode for the management of cucumber moth, Diaphania indica (Saunders) (Lepidoptera: Crambidae) in bitter gourd(Department of Agricultural Entomology, College of Agriculture, Vellayani, 2023-04-12) Gayathri, P S; Nisha, M SThe research work entitled “Entomopathogenic nematode for the management of cucumber moth, Diaphania indica (Saunders) (Lepidoptera: Crambidae) in bitter gourd” was carried out at Department of Entomology, College of Agriculture, Vellayani during 2020 to 2022. The objectives were to test the pathogenicity of entomopathogenic nematodes (EPNs) and to evaluate the effective EPN formulation against cucumber moth, D. indica in bitter gourd. The pathogenicity of two strains of entomopathogenic nematodes viz. Heterorhabditis indica Poinar and Steinernema carpocapsae Weiser were assessed against 3rd instar larvae of D. indica and Henosepilachna septima Dieke. Three different formulations viz. sponge, talc and alginate gel of the effective EPN strain were prepared and stored up to 11 weeks. Then, the survival percentage and virulence of infective juveniles (IJs) in each formulation was evaluated. A pot culture study was also conducted to evaluate the pathogenicity of effective EPN formulation against D. indica in bitter gourd. In the pathogenicity test, H. indica @ 100 IJs recorded highest mortality percentage of 42.50 for D. indica and 40.00 for H. septima at 24 Hours After Treatment (HAT). No mortality was observed for S. carpocapsae at all the concentration levels (10, 20, 50 and 100 IJs) for D. indica at 24 HAT. At 48 HAT, hundred per cent mortality was recorded only for H. indica at 100 IJs and it was on par with H. indica at 50 IJs. Both H. indica and S. carpocapsae at 50 and 100 IJs showed hundred per cent mortality at 60 HAT. All treatments showed hundred per cent mortality at 72 HAT. The number of IJs emerged from cadavers were slightly more for H. indica than S. carpocapsae for the same concentration of IJs. From the 1st experiment, H. indica was found to be more effective than S. carpocapsae against D. indica and H. septima. Therefore, survival percentage of IJs of H. indica were evaluated in different formulations. Highest survival percentage (100 per cent) was observed in alginate gel formulation in 1st week and it was on par with talc formulation up to 2 weeks. More than 50% survival of IJs was observed upto 8 weeks in alginate gel, 6 weeks in talc, 5 weeks in sponges and 3 weeks in water. 112 Results on virulence of IJs in different formulations revealed that IJs from alginate gel recorded mortality percentage ranging from 32.50 to 100.00 and 0.00 to 23.33 in 1st and 11th week of storage respectively against D. indica. It was statistically on par with freshly harvested juveniles at 72 HAT up to 5th week of storage. The next best formulation was found to be talc which was on par with freshly harvested juveniles at 72 HAT up to 4th week of storage. In the pot culture study, it was observed that the mortality of D. indica caused by IJs from alginate gel-based formulation of H. indica @ 4g L-1 (42.22 and 68.88) and talc- based formulation of H. indica @ 20g L-1 (40.00 and 68.88) was superior to talc-based formulation of Beauveria bassiana @ 2% (26.66 and 62.22) and neemazal 1% @ 0.2% + tween 80 (1%) (17.77 and 42.22) at 1 and 3 DAT respectively. The effect of H. indica was on par with talc-based formulation of B. bassiana @ 2% and neemazal 1% @ 0.2% + tween 80 (1%) at 5 and 7 DAT. At the same time, the highest mortality (100 per cent) was obtained for chlorantraniliprole 18.5SC@ 30g a.i. ha-1. The damage caused by D. indica ranged from 16.92 to 34.99 in alginate gel-based formulation of H. indica @ 4g L-1 and 19.97 to 41.74 in talc- based formulation of H. indica @ 20g L-1. Its effect on damage of leaves was on par with talc-based formulation of B. bassiana @ 2% of damage percentage 28.57, 40.21 and 41.00 at 3, 5, and 7 DAT respectively. Effect of H. indica formulations on the emergence of Bactrocera cucurbitae (Coquillett) from soil was studied under in vitro. Soil treated with alginate gel-based formulation of H. indica @ 4g L-1 and talc- based formulation of H. indica @ 20g L-1 recorded 16.66 per cent emergence of B. cucurbitae and its effect was on par with chlorantraniliprole 18.5SC@ 30g a.i. ha-1. Based on the present study, it can be concluded that H. indica can be stored in formulations viz. alginate gel and talc for better shelf life and it can be used as a biocontrol agent against D. indica, H. septima and B. cucurbitae in bitter gourd.Item Botanical-chemical pesticide combinations for managing cowpea aphid Aphis craccivora Koch(Department of Agricultural Entomology, College of Agriculture, Vellayani, 2023-03-27) Janu S Nair; Santhosh Kumar, TThe present investigation on “Botanical-chemical pesticide combinations for managing cowpea aphid Aphis craccivora Koch” was conducted at the Department of Agricultural Entomology, College of Agriculture, Vellayani during 2020 to 2022 with an objective to study the effect of botanical-chemical pesticide combinations for managing cowpea aphid Aphis craccivora in cowpea. Fourteen treatments namely Neem oil emulsion 2%+ Thiamethoxam 0.02%, Neem oil emulsion 2%+ Thiamethoxam 0.01%, Neem oil emulsion2%+ Thiamethoxam 0.005%, Pongamia oil emulsion 2%+Thiamethoxam 0.02%, Pongamia oil emulsion 2%+ Thiamethoxam 0.01%, Pongamia oil emulsion 2%+Thiamethoxam 0.005%, Andrographis formulation 5 % (Bhavyasree, 2019) +Thiamethoxam 0.02%, Andrographis formulation 5 % (Bhavyasree, 2019) +Thiamethoxam 0.01%, Andrographis formulation 5 % (Bhavyasree, 2019) +Thiamethoxam 0.005%, Neem oil emulsion 2%, Pongamia Oil emulsion 2%, Andrographis formulation 5% , Thiamethoxam 0.02% and Untreated control were evaluated against A. craccivora with three replications maintained under laboratory conditions. The mortality of the test insect was recorded at 12, 24 and 48 h after treatment and the data were statistically analysed. After 24 h of treatment, the highest mortality was shown by Thiamethoxam 0.02% (88.89 per cent), followed by Pongamia oil emulsion 2% +Thiamethoxam 0.02% (76.67 per cent) and Neem oil emulsion 2% + Thiamethoxam 0.02% (70 per cent). After 48h of treatment, same trend was observed and Thiamethoxam 0.02% recorded highest mortality (99 per cent), followed by Pongamia oil emulsion 2% +Thiamethoxam 0.02% (90.44 per cent) and Neem oil emulsion 2% + Thiamethoxam 0.02% (81.89 per cent). Based on the in-vitro study, three treatments were chosen for field evaluation namely Pongamia oil emulsion 2% + Thiamethoxam 0.02%, Neem oil emulsion 2% + Thiamethoxam 0.02% and Thiamethoxam 0.02%. Three prophylactic sprays were given at 15, 35 and 55 days after sowing for field evaluation and data were recorded at 1,3,5 and 7 days after treatment. The field data were evaluated using the 2 Way Analysis of Covariance (ANCOVA). The treatments Pongamia oil emulsion 2% + Thiamethoxam 0.02% and Neem oil emulsion 89 2% + Thiamethoxam 0.02% showed significantly lower population of aphid A. craccivora when compared with the chemical check and control. Seven days after first spray, the mean population of aphids per plant were significantly lower in the plots treated with Pongamia oil emulsion 2% + Thiamethoxam 0.02% (1.36 per plant) followed by the Neem oil emulsion 2%+ Thiamethoxam 0.02% (1.94 per plant) and both the treatments exhibited a steady decline in the aphid population when compared with control. The similar trend was followed in the second spray (35 days after sowing) and third spray (55 days after sowing). Testing the effectiveness of these treatments against pod bugs, Riptortus pedestris, the results were similar to that of A. craccivora population. The effects on the natural enemies viz, coccinellid (adult and larvae), brown lacewings, spiders and syrphids were recorded. The analysed data showed that the plots treated with Pongamia oil emulsion 2% + Thiamethoxam 0.02% and Neem oil emulsion 2% + Thiamethoxam 0.02% harboured significantly higher population of natural enemies when compared with the standard chemical check. Symptoms like yellowing, scorching, necrosis, epinasty and hyponasty were observed for phytotoxicity studies and the above treatments did not exhibit any form of phytotoxicity. All the treatments exhibited significant variation in fresh pod weight. The highest yield was recorded in the plots treated with Pongamia oil emulsion 2%+Thiamethoxam 0.02% (854 g/plot), which was followed by Neem oil emulsion 2%+Thiamethoxam 0.02% (776 g/plot). Traces of chemical residue (0.011ppm) were detected in chemical check (Thiamethoxam 0.02%), but it is below the limit of quantification (< LOQ), whereas the plots treated with Pongamia oil emulsion 2% + Thiamethoxam 0.02% and Neem oil emulsion 2% + Thiamethoxam 0.02%, did not detect any residue. From the study, it can be concluded that the combination of Pongamia oil emulsion 2% + Thiamethoxam 0.02% and Neem oil emulsion 2% + Thiamethoxam 0.02%, were effective in controlling aphid and pod bug population and they also supported the population of natural enemies when compared to chemical check (Thiamethoxam 0.02%). The chemical-botanical combinations supported good yield of cowpea and also reported thiamethoxam residue below limit of quantification.Item Morphological and molecular characterization of eastern honey bee (Apis cerana Fabricius) in Kerala(Department of Agricultural Entomology, College of Agriculture, Vellayani, 2023-06-09) Chinchu P Babu.; Amritha V SAn investigation on “Morphological and molecular characterization of eastern honey bee (Apis cerana Fabricius) in Kerala” was carried out at the Department of Entomology, College of Agriculture, Vellayani during 2017-2022 with the objective to identify the morphological and genetic diversity of eastern honey bee (Apis cerana Fabricus) in southern, central and northern zones of Kerala. Survey was conducted in three zones of Kerala viz., southern, central and northern zones. Twenty worker bees each were collected from 75 colonies (feral /natural colonies as well as managed/ domesticated hives) of twenty five localities representing each zone. The nesting habitat, nesting site, nest height and nest characteristics of honey bee colonies from forest areas in Kerala were examined. Feral colonies of cavity nesting honey bees were found to inhabit the primary forests, disturbed and undisturbed lands as well as agricultural lands in Kerala. Tree hollows, rock crevices, mud wall, termite mound, letter box and mud pot were the nesting sites of cavity nesting bees in Kerala and majority of the bees were found to occur at a nest height of 0 cm to 200 cm. The number of combs in the colony varied from five to twelve. An exploration of foraging sources of honey bees in forest areas were done for the first time in Kerala via metabarcoding of rbcL (ribulose- bisphosphate carboxylase) gene. Plants belonging to 256 genera were identified as foraging sources of honey bees in forest areas of Kerala with Gossypium as the abundant genus in southern zone, Elaeis in central zone and Drypetes in northern zone. Seventeen genera of plants were common in all the three zones of Kerala i.e. Pterocarpus, Cannabis, Prunus, Ceiba, Ulex, Galatella, Myosotidium, Vachellia, Valeriana, Cassia, Androsace, Senna, Luisia, Cocos, Peliosanthes, Esmeralda, and Parkia among which Pterocarpus, Cannabis, Prunus, and Ceiba were the prevalent genera as the foraging source of honey bees in forest areas of Kerala. As part of the morphological studies, five worker bees from each colony were dissected and subjected to standard morphometric analysis using 29 parameters. No significant differences were observed in most of the morphological parameters among the zones. Based on elevation, the populations were classified as ‘Plain’ (<300 m above MSL) and ‘Hill’ (>300m above MSL) populations and ‘t test’ analysis among the populations showed highly significant differences across most of the size related morphometric characters viz., ratio of head length and width (HLW), distance between ocelli (DBO), ocello-ocular distance (OOD), proboscis length (PL), antennal length (AL), ratio of length and width of fore wing (FWLW), cubital index (CI), wing angles (A 32, A 38), length of third tergite (3TEL) and length of fourth tergite (4 TEL) and ratio of length and width of wax plate (WPLW). Moreover, the ‘Hill’ populations of honey bees exhibited higher values for most of the size related as well as wing related characters. Factor analysis yielded six factors with Eigen value > 1. The major factor (F1) was derived from honey bee size related characters (HLW, PL, AL, CI, 3TEL, 4TEL and WPLW) with high factor loadings in between 0.66 to 0.92 accounting for 35 per cent of the variation among the samples. Hence, these characters were found to be the main indices that could be used to discriminate among the populations. The hierarchical cluster analysis (HCA) of 75 populations with 29 morphological characters revealed the presence of two main clusters, ‘Plain’ group cluster and ‘Hill’ group cluster, the same being confirmed in linear discriminant analysis (LDA). The correlation analysis of morphological traits with elevation revealed that proboscis length (PL), antennal length (AL), cubital index (CI), ratio of head length and width (HLW), ratio of length and width of wax plate (WPLW), length of third tergite (3 TEL) and length of fourth tergite (4 TEL) exhibited positive linear correlation with topographic elevation. The ‘Hill’ and ‘Plain’ populations of honey bees exhibited variations in the colour and pigmentation pattern of different morphological traits viz., second tergite, third tergite, third sternite and abdomen. The everted endophallus of honey bee drones showed variations in the vestibulum, cervix and bulb indicating reproductive isolation between ‘Plain’ and ‘Hill’ populations of cavity nesting bees in Kerala. Surface pattern of bulb and vestibulum were detected through scanning electron microscopy (SEM) imaging wherein they exhibited variations in the surface structures. Molecular characterization of 75 populations of cavity nesting bees in Kerala was also carried out by amplifying the mitochondrial cytochrome oxidase I (COX I) gene. Phylogenetic analysis of the 75 bee populations from Kerala using maximum likelihood method identified the ‘Plain’ group as A. indica Fabricus, 1798 and the ‘Hill’ group as A. cerana Fabricus, 1793. Haplotype analysis of the populations revealed the existence of fifteen COX I haplotypes in Kerala, out of which fourteen were new haplotypes. Pair wise genetic distance of the samples revealed high nucleotide divergence (5.1% - 7.0%) between A. indica and A. cerana. The network analysis of haplotypes also supports the divergence between A. indica and A. cerana in Kerala. These fifteen nucleotide sequences of the haplotypes were submitted to NCBI Genbank and BOLD. Comparative metagenomic analysis of gut microbiome of A. indica and A. cerana revealed variations in the abundance of gut microbiome between the two species. The abundant genus recorded in A. indica was Lactobacillus while in A. cerana Gilliamella was the prominent genus. Morphological and molecular analysis of 75 populations from Southern, Central and Northern zones revealed the existence of two discrete populations of cavity nesting honey bees in Kerala i.e. ‘Plain’ population and ‘Hill’ population. Significant variations in the morphometric parameters of the bee populations were observed at elevations rather than the zones. Studies on the external genitalia revealed reproductive isolation between ‘Plain’ and ‘Hill’ populations of cavity nesting bees in Kerala. Haplotype analysis revealed fifteen COX I haplotypes of cavity nesting bees in Kerala, wherein fourteen haplotypes were new from Kerala. Thus, the present study revealed the existence of two species of cavity nesting bees in Kerala i.e. the Plain group, A. indica and Hill group, A. cerana.Item Pests of curry leaf Murraya koenigii (L.) Spreng. and their management(Department of Agricultural Entomology, College of Agriculture , Vellayani, 2023-04-25) Karthika S; Malini NilamudeenThe study entitled “Pests of curry leaf Murraya koenigii (L.) Spreng. and their management” was carried out at the Department of Agricultural Entomology during the period 2020-2022. The main objectives of the study were to document the pests infesting M. koenigii, natural enemies associated with the pests, biology of major pests, their nature of damage and symptoms, and to develop effective management practices. The documentation conducted at twenty homesteads of Thiruvananthapuram district for a period of one year, recorded twenty pests. The pests found infesting curry leaf were lemon butterflies (Papilio demoleus Linnaeus and Papilio polytes Linnaeus), citrus psyllid (Diaphorina citri Kuwayama), citrus green mite (Schizotetranychus baltazari Rimando), curry leaf tortoise beetle (Silana farinosa (Boheman)), citrus leaf roller (Psorosticha zizyphi (Stainton)), black looper (Hyposidra talaca (Walker)), mealybug (Rastrococcus iceryoides (Green)), scale insects (Pinnaspis strachani (Cooley) and Icerya aegyptiaca (Douglas), blackflies (Aleurocanthus terminaliae Dubey & Sundararaj, Aleurolobus orientalis David & Jesudasan)), whitefly (Aleuroclava complex Singh), hairy caterpillar (Olene mendosa Hübner), tortoise beetle (Cassida exilis Boheman), ash weevil (Myllocerus brevirostris Marshall), bean bug (Riptortus pedestris (Fabricius), coreid bug (Dasynus antennatus Kirby), leafhopper (Empoasca sp.), bagworms (unidentified), cow bug (unidentified), slug caterpillar (unidentified) and planthopper (unidentified). Out of the documented pests, H. talaca, P. strachani, I. aegyptiaca, A. terminaliae, A. orientalis, Empoasca sp., C. exilis and M. brevirostris were reported for the first time from Kerala as pest of curry leaves. A total of eight spiders, one praying mantid, a reduviid bug, two predatory ants, three coccinellids and three parasitoids were recorded. Spiders documented were Burmese lynx spider (Oxyopes birmanicus Thorell), lynx spider (Oxyopes javanus Thorell), white lynx spider (Oxyopes shweta Tikader), two-striped jumping spider (Telamonia dimidiata (Simon)), wasp-mimic jumping spider (Rhene flavicomans (Simon)), crab spider (Camaricus formosus Thorell), jumping spider (Carrhotus sp.) and heavy-bodied jumper spider (Hyllus semicupreus (Simon)). Praying mantid (Odontomantis pulchra Olivier), reduviid bug (Scipinia horrida (Stål)), ants (Camponotus compressus (Fabricius) and Diacamma ceylonense Emery), and three coccinellid beetles of the genus Phrynocaria sp. were also recorded. Parasitoids obtained were larval parasitoid (Tachinidae) from P. polytes, nymphal parasitoid Tamarixia radiata (Waterson) from D. citri nymphs and pupal parasitoid Brachymeria apicicornis (Cameron) from S. farinosa. A consolidated documentation of spiders and other defenders from curry leaf is first of its kind from Kerala. Biology studies were carried out for S. farinosa, D. citri, and P. polytes under laboratory conditions. P. polytes had a mean number of days of 3.30 + 0.15, 20.30 + 0.26 and 8.40 + 0.16 as egg, larval and pupal period, respectively. S. farinosa had a mean of 5.30 + 0.15, 16.80 + 0.29, 5.00 + 0.21 and 81.10 + 0.80 days as egg, grub, pupal and adult period, respectively. D. citri had a mean of 3.50 + 0.15, 12.50 + 0.41 and 25.75 + 0.66 days egg, nymphal and adult period, respectively. To evaluate the qualitative damage due to pest infestation, chlorophyll, carotenoids, ascorbic acid, and tannins in mite infested (broad, narrow leaved) and psyllid infested (broad leaved) leaves were compared with their quantity in uninfested broad and narrow leaved samples. Murraya exotica, a closely related species of M. koenigii was found resistant to most of the pest species recorded from the latter. Hence, a comparative study of its biochemical constituents was also done. Results showed a decline in chlorophyll content by 13.64 and 63.16 per cent in mite infested broad and narrow leaved samples, over their respective control and a reduction of 36.36 per cent in psyllid infested samples. In psyllid infested broad leaved samples, carotenoid content got reduced by 18.00 per cent over its uninfested control whereas a reduction of 28.96 per cent occurred in mite infested narrow leaved samples over its respective control. Quantity of ascorbic acid also declined by 30 per cent in mite infested broad leaved sample whereas other samples showed no significant reduction. Tannin content increased by 6.51 and 20.20 per cent in mite and psyllid infested broad leaved samples, respectively over uninfested samples whereas it showed a reduction of 13.60 per cent in mite infested narrow leaved sample. M. exotica showed a decrease in chlorophyll, carotenoids and tannin content by 31.82, 16.85 and 5.88 per cent, respectively and an increase in ascorbic acid content by 42.68 per cent over uninfested M. koenigii. A field experiment conducted at farmer’s field for evaluating effective management practices against curry leaf pests revealed that among biopesticides, neem garlic soap formulation- KAU Raksha @ 10 g L-1 and talc based formulation of L. lecanii NBAIR Vl 8 @ 20 g L-1 were effective in reducing the population of psyllids by 65 and 58.17 per cent and damage by 51.48 and 60.53 per cent, respectively 14 DAT. Against mites, Horticultural Mineral Oil HMO @ 25 mL L-1 and talc based formulation of L. lecanii NBAIR Vl 8 @ 20 g L -1 were effective in reducing the population by 39.18 and 33.44 per cent and damage by 35.74 and 42.37 per cent, respectively. Whitefly was effectively managed by talc based formulation of L. lecanii NBAIR Vl 8 @ 20 g L-1 which reduced the population and damage of whitefly by 75.23 and 63.23 per cent, respectively 14 DAT. The chemical insecticide, chlorantraniliprole 8.8 % w/w + thiamethoxam 17.5 % w/w SC @ 150 g a.i ha-1 was effective in reducing psyllid, mite and whitefly population by 89.91, 49.76 and 76.63 per cent and damage by 79.08, 55.57 and 81.04 per cent, respectively over untreated control, 14 DAT. All chemical treatments were toxic to spiders and caused cent per cent reduction of spiders, 14 DAT. Harvest time residue analysis showed that, the residues of all the three insecticides viz., chlorantraniliprole, thiamethoxam and quinalphos were below the limit of quantification, at 14 DAT. The present investigation documented twenty pests, fifteen predators and three parasitoids from curry leaf ecosystem. Based on the extent of incidence, D. citri, P. polytes, S. baltazari, and S. farinosa are categorised as major pests. The biochemical analysis proved the qualitative deterioration due to pest damage, which emphasise the importance of developing good agriculture practice in curry leaf pest management as it is an important raw material in ayurvedic medicinal preparations. For managing pests infesting curry leaves, talc based formulation of L. lecanii NBAIR Vl 8 @ 20 g L-1 , neem garlic soap formulation-KAU Raksha @ 10 g L-1 or Horticultural Mineral Oil HMO @ 25 mL L-1 can be recommended as non-chemical options whereas the insecticide chlorantraniliprole 8.8 % w/w + thiamethoxam 17.5 % w/w SC @ 150 g a.i ha-1 can be recommended for managing severe pest infestation.Item Stingless bee foraging pattern in ornamental plants(Department of Agricultural Entomology, College of Agriculture , Vellayani, 2023-05-03) Anchu, C L; Vijayasree, VThe present investigation on “Stingless bee foraging pattern in ornamental plants” was conducted at the Department of Agricultural Entomology, College of Agriculture, Vellayani, during 2020-2022. The objective of the study was documentation of the foraging pattern of stingless bees in nectariferous and polleniferous ornamental plants and preparation of floral calendar. Flowers were observed from identified ornamental plants at full bloom stage and their flowering period and floral characteristics were studied. Foraging activity of stingless bee was studied and observations were recorded from 0700 h to 1800 h from September 2021 to August 2022. A total of 20 ornamental plant species were identified on the basis of stingless bee foraging for nectar and pollen of which, 9 plant species were found producing flowers year round and remaining as seasonal. Major nectar producing plants were identified as coral vine (Antigonon leptopus Hook. and Arn) and scarlet bush (Hamelia patens Jacq). Pollen producing plants were identified as moss rose/sun plant (Portulaca grandiflora L), water lily (Nymphaea sp), rose (Rosa spp), scented rose (Rosa bourboniana L), ornamental palm (Syagrus romanzoffiana cham), lemon vine (Pereskia aculeate L), marigold (Tagetes erecta L) and sunflower (Helianthus annuus I). The ornamental plants providing both nectar and pollen were found to be hibiscus (Malvaviscus arboreus B, Hibiscus rosa-sinensis L), peacock plant (Caesalpinia pulcherrima L), chinese powder puff (Combretum constrictum L), chinese ixora (Ixora chinensis L), cape honey suckle (Tecoma capensis L), peregrina/ spicy jatropha (Jatropha Pandurifolia L) and euphorbia (Euphorbia mili L). Among the ornamental plants foraged by bees, the predominant family was Asteraceae followed by Rubiaceae, Malvaceae and Euphorbiaceae. The majority of bee flora were of strong orange, yellowish white followed by strong red and vivid reddish orange and tubular and cup-like shapes. Studies on foraging activity of stingless bee revealed that the peak activity was recorded during January and March with peak foraging activity from 1000 h to 0100 h. Among the year round flowering plants, maximum foraging rate was observed in Antigonon leptopus and among seasonal flowering plants, it was Syagrus romanzoffiana. Longest time spent by foragers was recorded as 30.44 sec during 1000-1200h of the day. Maximum time spent was observed in Nympheae sp. followed by Malvaviscus arboreus. Relationship between foraging rate and weather parameters viz temperature, relative humidity, wind velocity, rainfall and sunshine hours were done. Significant positive correlation was observed with temperature and number of foragers in case of Antigonon leptopus (0.221), Caesalpinia pulcherrima (0.271), Portulaca grandiflora (0.402), Jatropha pandurifolia (0.454) and Syagrus romansoffiana (0.213). Significant negative correlation was observed between relative humidity and number of foragers in case of Antigonon leptopus (-0.157), Hamelia patens (-0.216), Nymphaea sp. (-0.356), Caesalpinia pulcherrima (-0.256), Portulaca grandiflora (-0.295), Jatropha pandurifolia (-0.311), Malvaviscus arboreus (-0.142), Combretum constrictum (-0.293) and Syagru sromansoffiana (-0.401). Significant negative correlation was found between rainfall whereas significant positive correlation was recorded with sunshine hours and foraging rate. Thus in this study two nectar producing plants, eight pollen providing plants and 10 nectar and pollen producing ornamental plant species were identified. The foraging activity of bees varied in a day with the peak foraging activity during 1000 h to 0100 h. Bee floral calendar was prepared by using data of year round observation which can aid the farmers in providing the identified bee flora in particular month so that the bees can exploit these resources available in their surroundings.Item Bioecology of major coccinellid predators of Kerala(Department of agricultural entomology, college of agriculture , Vellayani, 2023-07-07) Anusree, S S; Anitha, NAn investigation on “Bioecology of major coccinellid predators of Kerala” was carried out at Department of Entomology, College of Agriculture, Vellayani during 2017-2022 with the objective to identify major coccinellid predators of pests infesting agricultural crops from agro ecological zones of Kerala and to study biology and predatory potential of select coccinellids. In the present investigation, 40 species of predatory coccinellids belonging to 23 genera under 6 tribes in the Subfamily Coccinellinae were illustrated. Taxonomic study on tribes Aspidimerini and Chilocorini resulted in the identification of three species in each tribe. Examination on specimens of tribe Coccidulini resulted in identifying 16 species within five genera. 11 species belonging to nine genera were illustrated under tribe Coccinellini. A single species was illustrated and studied under tribe Hyperaspidini. The specimens studied under tribe Sticholotidini belonged to six species within four genera. Among the 40 illustrated species, 28 species were identified, while identity of 12 species are to be confirmed, of which three are putative new species. Phrynocaria perfida Poorani collected and illustrated during this investigation were confirmed and described as a new species (Poorani et al., 2021). Chilocorus sp.1 and Scymnus (Pullus) sp.4 are the other two putative new species. Phrynocaria perrotetti (Mulsant), Cryptogonus orbiculus (Gyllenhal) and Sticholotis ferruginea (Gorham) are new records from Kerala.Item Microbial formulations for the management of spodoptera litura F.(Department of agricultural entomology, college of agriculture , Vellayani, 2023-06-30) Hari Sanker S S.; Faizal, M HThe present study entitled “Microbial formulations for the management of Spodoptera litura F.” was conducted in the Department of Agricultural Entomology, College of Agriculture, Vellayani during 2018-2022 with an objective to develop ecofriendly, biologically based formulations comprising of entomopathogenic fungi (EPF) and nuclear polyhedrosis virus (NPV) in plant derived carrier materials for the management of the polyphagous pest S. litura.