Feasibility study on hexacopter UAV based sprayer for application of environment-friendly biopesticide in guava orchard

Aim: To study the feasibility of hexacopter UAV based sprayer for application of environment-friendly biopesticide in guava orchard. Methodology: Field experiments were conducted in Punjab (India) during 2020. UAV was evaluated for spraying environment-friendly bio-pesticidein guava orchard. UAV was operated at 2.0 m height above the tree top.The water and oil sensitive papers were fixed on the outer side as well as inside of selected guava trees at four different canopies. Organic neem seed kernel based azadirachtin 0.15% EC biopesticide was used at recommended dose. After spraying, all water and oil sensitive papers were collected for further laboratory analysis. All spray quality parameters, i.e., coverage (%), droplet density (droplets cm-2), droplet size (µm) and uniformity coefficient were determined. For the efficacy of drone sprayer insects were counted before and 1, 2, 7 days after spray (DAS) and reduction in number of insects was calculated. Results: The on-flight field capacity of spraying with UAV was 3.0-3.3 ha h-1 whereas actual field capacity was found to be 2.0-2.3 ha h-1. The total mean coverage area was found in the range of 2.67-10.67%. The maximum coverage was at the top canopy (inner and outer) of tree which was significantly higher than all other observation points on the canopy. The mean droplet density was found in the range of 14.67-28.33 droplets cm-2. The highest droplet density (28.33 droplets cm-2) was found at the top outer side of the tree canopy. The volume median diameter was found in the range of 208.0-418.3 µm whereas, number median diameter was in the range of 138 to 269 µm. The percent reduction in aphid population 1, 2 and 7 days after spray (DAS) was 38.06, 68.28 and 62.69%, respectively whereas it was 47.95, 78.69 and 70.90% with knapsack sprayer. Interpretation: Hexacopter UAV sprayer is effective in terms of quality of spray and effective control of aphid population.

Comparative studies of codon usage profile of Anisakis simplex (Nematoda) and Carassius gibelio (Prussian carp)

Aim: The aim of the present study was to understand the molecular relationship between nematode (parasite) and fish (host) through codon usage bias (CUB) analysis. Methodology: The Codon usage bias analysis has been performed in fish Carassius gibelio (Prussian carp) and nematode fish parasite Anisakis simplex. The complete coding sequences (CDS) of C. gibelio (Prussian carp) and A. simplex (Nematode) were retrieved from National Center for Biotechnology Information and followed to that we have performed bioinformatics analysis to understand the codon usage pattern between host and parasite. Results: Different CUB indices like Relative synonymous codon usage (RSCU), Effective number of codons (ENC), Codon adaptation index (CAI) and Codon bias index (CBI) revealed a similar pattern in the codon usage in C. gibelio and A. simplex. In addition, inclusive analysis using different plots (ENC, parity, neutrality) had shown the influence of both the evolutionary forces i.e mutational and translational selection on codon usage pattern. This describes the role of evolutionary forces in determining the conserved genome to establish species-specific function-level differences for efficient survival. Interpretation: The present study elucidated the association between Carassiusgibelio (host) and Anisakis simplex (parasite) based on the similar pattern of codon usage bias between both the species.

The effect of flood on seasonal dynamics of Haemaphysalis (Acari: Ixodidae) tick vectors in Western Ghats forest area of Kerala, South India

Aim: Climate and weather conditions play a crucial role in the dynamics and distribution of ticks and tick-borne diseases. In this study, we explored the influence of a heavy rainfall (flood) occurrence on the seasonal activity and density of host-seeking Haemaphysalis tick vectors in Wayanad district, Kerala, India. Methodology: Wayanad district in Kerala state was selected as the study area. Ticks were collected from December 2017 to May 2019, monthly for five consecutive days by dragging method. Tick density was analyzed with climate data obtained from the meteorological station. Results: The total number of ticks collected post-flood decreased to 59% in Kurichiyad (site 1) and 63% in Muthanga (site 2), and the seasonal nymphal peak density was shifted. A seasonal peak of tick activity was normally observed from December to February. This peak occurrence was missing after flood in the study areas created with waterlogging and vegetation overgrowth. Interpretation: The present study revealed the effect of flood events in the study sites with significant differences in the abundance of five Haemaphysalis tick species during pre and post-flood periods and forest and wildlife habitats. This difference in the changing climatic conditions and increasing annual flood seasons in the Western Ghats may shift this region's ticks questing activity and tick-borne disease ecology.

Altitudinal variation in plant community, population structure and carbon stock of Quercus semecarpifolia Sm. forest in Kumaun Himalaya

Aim: To study the impact of altitudinal variation on plant community composition, structure, dispersion and regeneration status of Quercus semecarpifolia forest in Kumaun Himalaya. Methodology: Along the altitudinal gradient, the forest stands between 2400 and 2610 m asl were selected at low, mid and high altitude. The phyto-sociological analysis was carried by laying ten quadrats of 10m × 10m at each site. Soil samples were collected with the help of soil corer from two depths. Various ecological indices and population structure were investigated for each forest stand and regeneration status of forest was predicted by the population size of seedlings, saplings and trees. Tree biomass was estimated using allomatric equations and carbon stock was determined by multiplying biomass of species to factor 0.475. Results: With increasing altitude the number of tree species decreased and the shrub species richness increased, while herb species showed a unimodel pattern. Q. semecarpifolia was the dominant tree species at all the three sites with the IVI values of 220.14, 255.22 and 286.23 at LA, MA and HA, respectively. A complete absence of Q. semecarpifolia seedlings indicated no regeneration in low and high altitude stands while low proportion of seedlings in mid altitude forest stand indicated poor regeneration. Soil was acidic (pH 5.66-5.86), with higher silt content and showed decreasing pattern in physico-chemical properties with increasing altitude. The biomass of tree layer ranged from 871.49 to 1050.17 t ha-1. The tree layer carbon stock was maximum in high altitude forest (498.84 t ha-1) which was largely contributed by bole, stump roots and branches. Interpretation: Variation in species richness, distribution pattern and regeneration potential is related to site characteristics governed by altitude and require various efforts to conserve and protect these forests to check ecosystem imbalance.

Correlation studies on pathological changes in brain with neurotransmitters and behavioural changes in Balb/c mice

Aim: To determine the plasma neurotransmitters simultaneously and to find any correlation with pathological changes in the hippocampus and Purkinje cells and their relation with behavioral changes in Balb/c mice. Methodology: In the present study, both sexes of Balb /C mice were divided into two groups (4 males and 4 females; n = 8): Both the groups were given a single dose of either saline or sodium valproate (400mg kg-1) respectively through subcutaneous injection on PND 14. Behavioural tests were conducted on mice pups on various postnatal days till 40th day. On PND 41, blood samples were collected from all the animals for quantification of the neurotransmitters (serotonin, dopamine, and noradrenalin) in plasma, animals were sacrificed by cervical dislocation and whole brain was isolated for histological examination of the Purkinje cells and hippocampus. Results: Sodium valproate exposed animals showed loss of motor skill development (delayed negative geotaxic response), increased locomotor activity, increased anxiety, and retardation in water maze performance, and lower social interaction. Histopathological evolutions of cerebellum purkinje cells and hippocampus showed 40-50% atrophic cells in sodium valproate animals compared to control animals. Interpretation: The results of the present study indicate that Sodium valproate changes specific brain cell population in Balb/C mice, which might be the reason for the altered neurotransmitter levels, leading to behavioural changes in these animals.

Indian scenario on the occurrence of a dreaded insect pest Pink bollworm, Pectinophora gossypiella on Bt cotton-A review

The pink bollworm, Pectinophora gossypiella, has become a significant production constraint on Bt cotton in India. This problem is unique to India because the pest has developed multi-fold resistance to Cry toxins in many Indian populations but not in other countries. Most Indian populations have developed multifold resistance to Cry 1 Ac and Cry 1Ac + Cry 2 Ab toxins. Year-round cultivation of long-duration Bt cotton hybrids on a large scale has a pronounced impact on the incidence. Also discussed other factors responsible for the occurrence of pink bollworm on Bt cotton in India. Insecticide Resistance Management (IRM) strategies implemented by different cotton-growing countries globally; the USA, India, and China had a significant impact on the interaction of pink bollworm on Bt cotton. Huge selection pressure resulted in resistance to Cry toxins. Time-tested IPM, if implemented on a community basis focusing on pheromones technology and closed season, will help sustain the cotton cultivation in India in the future. Thus, this review aims to congregate exhaustive information on the history, biology, resistance to Bt cotton, and Integrated Management (IPM) options for the Indian scenario, which would help researchers in their future endeavors.

Description of a new species of queenfish, Scomberoides pelagicus from Indian seas

Aim: The study was carried out to ascertain whether morphotype of Scomberoides commersonnianus (Talang queenfish) existing along the Indian coast is a new species or not. Methodology: Talang queenfish and the morphotype were tested for their uniqueness using systematic and molecular tools. The morphometric and meristic details including otolith morphometry were analysed and compared for taxonomic divergence and Cytochrome Oxidase I and Cytochrome b gene sequences for quantifying genetic divergences. Results: The systematic analysis indicated significant morphometric differences between both. The otolith morphometry and phylogeny also confirmed the divergence between them, and qualified the morphotype as an independent species status and named Scomberoides pelagicus sp. nov. Interpretation: The new species is distinct by deep ovate body, concave dorsal head profile, anal fin origin anterior to second dorsal fin and pelvic to pectoral fin, helical arrangement of body scale and stout and less numerous gill rakers on the first gill arch. The phylogeny as on Cytochrome b and Cytochrome Oxidase 1 sequences are very distinct, with 11.2% and 2.0% divergence respectively. Their known distributional range are peninsular region of Indian coast, Malaysian region of the South China Sea and Manila Bay, Philippines.

Seasonal variation in population and biochemical contents of brown planthopper, Nilaparvata lugens (Stål)

Aim: The present study was undertaken on population dynamics and estimation of protein, water-soluble carbohydrates and glycogen contents in the brown planthopper, Nilaparvata lugens to explore their migratory behaviour. Methodology: Brown planthopper populations were monitored and collected using sweep nets from 23rd standard meteorological week (SMW) to 47th SMW during 2017 and 2018 rainy seasons to understand population dynamics of the pest. The protein, water-soluble carbohydrates and glycogen contents were estimated from the pest samples collected during 36th to 44th SMW in 2017 and 2018 rainy seasons. Results: Brown planthopper population were not observed in rice farm during 23rd SMW to 28th SMW during two years of study. However, macropterous form of the pest first appeared in the farm during 29th SMW and peaked during 43rd SMW. Thereafter, population declined and disappeared after 47th SMW during both the years. Water-soluble carbohydrates and glycogen contents varied significantly different weeks which remained low during 36th-39th SMW, however, increased gradually towards the end of the rainy season 2017 and 2018. On the other hand, protein content significantly varied among different weeks unlike the trend of water-soluble carbohydrates and glycogen. Interpretation: The study revealed the absence of brown plant hopper during summer season preceding rainy season, and the accumulation of bio-chemical compounds towards the end of rainy season under Delhi environment is perhaps suggestive of migration of the pest from unknown areas during rainy season to Delhi and likely preparedness of the pest for emigration to safer areas from Delhi, respectively.

Effect of mangosteen peel extract on BPA-exposed murine during gestation

Aim: To evaluate the potential protective effects of mangosteen peel extract against BPA-induced abnormalities on-pregnant mice fetus at implantation stage and offspring at post-parturition. Methodology: Pregnant mice were orally administered with BPA (100mg kg-1 b.wt.) and mangosteen peel extract (200mg kg-1 b.wt.) for 16 days. In order to evaluate the effect of MPE treatment on fetus at implantation stage, the pregnant mice were euthanized at day 18 and the fetus number and morphology were examined. Another group of treated dams, were allowed to undergo parturition for evaluating the of maternal weight, litter size and offspring sex-skewness. Results: Upon feeding Mangosteen peel extract (MPE), the average daily weight gain of dams were not significantly different from the control and BPA treated dams. The fetus derived from BPA treated dams were detected with abnormalities such as under development, haemorrhage and absence of vein, whereas fetus from dam treated with MPE and BPA as well as control were normal. The average litter size of all the treatment groups were not significantly different from the control group. BPA treated mice had lower pups survival up to 6 weeks compared to the groups treated with MPE and control. Test of proportion analysis showed BPA-treated group had significantly higher fraction female ratio. Interpretation: BPA is known as endocrine disruptor causing oxidative stress to female reproductive system, hence mangosteen peel extract contains antioxidant substances that have the potential to ameliorate the adverse effects of BPA exposure on dams during pregnancy and its fetus development.

Influence of probiotics on physico-chemical and organoleptic characteristics of sweet orange juice

Aim: The study was undertaken to evaluate the survival probiotic organisms and its influence on the physical, chemical, nutritional and sensory characteristics of sweet orange juice. Methodology: Two samples of probiotic juice were prepared with 10 percent innoculum containing LAB strains (Lactobacillus bulgaricus and Lactobacillus plantarum). Sample A (without encapsulated strains) and Sample-B (with encapsulated strains) were prepared and incubated for 10hrs at 35oC. After incubation, the physico-chemical analysis of both the samples were analyzed for TSS, pH, acidity, total sugars, reducing sugars and ascorbic acid content. Results: The results of TSS, pH, acidity, total sugars, reducing sugars and ascorbic acid content for sample –A and Sample –B were 11.4˚Brix, 3.51, 0.82 percent, 6.1 percent, 1.5 percent, 4.6 percent, 40mgml-1 and 11.6˚ Brix, 3.68, 0.77 percent, 6.4 percent, 1.7 percent, 4.9 percent, 40 mg ml-1, respectively. Sensory evaluation revealed that overall acceptance of probiotic juice containing encapsulated strains and free strains in the first week was 8.3 and 7.8, respectively. Even after 4 weeks of storage, the overall acceptance for juice with encapsulated strains was better than free strains with a score of 7.5 and 7.0 at the end of storage period. Interpretation: The sweet orange juice with encapsulated strains has high viable cell count (109cfu ml-1) even after 4 weeks of storage resulted in stable therapeutic probiotic sweet orange juice. It is further, suitable for commercial production of probiotic sweet orange juice with probiotic cultures.