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Stalk rot disease is a major constraint in maize production and till date reported to be caused by two to three species of phytopathogenic fungi but, in our present study, we disclose the first report of stalk rot is caused by complex species of phytopathogens, which belongs to five different genera. Therefore, to substantiate these findings, a total of 105 diseased samples of maize were collected from 21 different locations in six different geographical locations of India from which 48 isolates were used for the research study. Morphological features such as pigmentation, colony color, type of mycelium and pattern of mycelium was examined using macro and microscopic methods. A total of 11 different spp. of pathogens belonging to the five different genera: Fusarium verticillioides (56.25%), F. equiseti (14.5%), F. andiyazi (6.25%), F. solani (2.08%), F. proliferatum (2.08%), F. incarnatum (2.08%), Lasidioplodia theobrame (6.25%), Exserohilum rostrtum (4.16%), Nigrospora spp. (4.16%). and Schizophyllum commune (2.08%) were identified by different housekeeping genes (ITS, TEF-1α, RPB2 and Actin). Fusarium verticillioides, F. equiseti and F. andiyazi were major pathogens involved in stalk rot. This is the first report on F. proliferatum, F. solani, F. incarnatum, Lasidioplodia theobrame, Exserohilum rostrtum, Nigrospora spp. and Schizophyllum commune causing stalk rot of maize and their distribution in the different states of India. Studies on population dynamics of PFSR will enhance the understanding of pathogen behavior, virulence, or its association with different pathogens across India, which will facilitate the development of resistant maize genotypes against the PFSR. [ABSTRACT FROM AUTHOR]

Objective: Karan Fries (KF), a high-producing composite cattle was developed through crossing indicine Tharparkar cows with taurine bulls (Holstein Friesian, Brown Swiss, and Jersey), to increase the milk yield across India. This composite cattle population must maintain sufficient genetic diversity for long-term development and breed improvement in the coming years. The level of linkage disequilibrium (LD) measures the influence of population genetic forces on the genomic structure and provides insights into the evolutionary history of populations, while the decay of LD is important in understanding the limits of genome-wide association studies for a population. Effective population size (Ne) which is genomically based on LD accumulated over the course of previous generations, is a valuable tool for e valuation of the genetic diversity and level of inbreeding. The present study was undertaken to understand KF population dynamics through the estimation of Ne and LD for the longterm sustainability of these breeds. Methods: The present study included 96 KF samples genotyped using Illumina HDBovine array to estimate the effective population and examine the LD pattern. The genotype data were also obtained for other crossbreds (Santa Gertrudis, Brangus, and Beefmaster) and Holstein Friesian cattle for comparison purposes. Results: The average LD between single nucleotide polymorphisms (SNPs) was r2 = 0.13 in the present study. LD decay (r2 = 0.2) was observed at 40 kb inter-marker distance, indicating a panel with 62,765 SNPs was sufficient for genomic breeding value estimation in KF cattle. The pedigree-based Ne of KF was determined to be 78, while the Ne estimates obtained using LD-based methods were 52 (SNeP) and 219 (genetic optimization for Ne estimation), respectively. Conclusion: KF cattle have an Ne exceeding the FAO's minimum recommended level of 50, which was desirable. The study also revealed significant population dynamics of KF cattle and increased our understanding of devising suitable breeding strategies for longterm sustainable development. [ABSTRACT FROM AUTHOR]

Aulacophora lewisii Baly (Coleoptera: Chrysomelidae) is an important pest of Luffa acutangula (L.) Roxb. (Cucurbitaceae) in India. Larvae of A. lewisii feed on the roots, while adults consume leaves of L. acutangula. In the current study, effects of three L. acutangula cultivars (Abhiskar, Debsundari, and Jaipur Long) on the life table parameters by age-stage, two-sex approach, and key digestive enzymatic activities (amylolytic, proteolytic, and lipolytic) of the larvae and adults of A. lewisii were determined. Further, nutrients (total carbohydrates, proteins, lipids, amino acids, and nitrogen content) and antinutrients (total phenols, flavonols, and tannins) present in the roots and leaves of three cultivars were estimated. The development time (egg to adult emergence) was fastest and slowest on Jaipur Long (31.80 days) and Abhiskar (40.91 days), respectively. Fecundity was highest and lowest on Jaipur Long (279.91 eggs) and Abhiskar (137.18 eggs), respectively. The intrinsic rate of increase (r) was lowest on Abhiskar (0.0511 day−1) and highest on Jaipur Long (0.0872 day−1). The net reproductive rate (R 0) was lowest on Abhiskar (23.32 offspring female−1). The mean generation time (T) was shortest on Jaipur Long (52.59 days) and longest on Abhiskar (61.58 days). The amylolytic, proteolytic, and lipolytic activities of larvae and adults of A. lewisii were highest and lowest on Jaipur Long and Abhiskar, respectively. The lower level of nutrients and higher level of antinutrients influenced higher larval development time and lower fecundity of A. lewisii on Abhiskar than other cultivars. Our results suggest that Abhiskar cultivar could be promoted for cultivation. [ABSTRACT FROM AUTHOR]

Summary: Turmeric (Curcuma longa) is a major spice of Indian origin. Turmeric is commonly used in Ayurvedic and Siddha medicine, and also in Indian cuisine. India produces nearly 1.2 million tonnes (Mt) of turmeric annually and is one of the world's largest producers. Turmeric production is limited by a number of biotic and abiotic factors. Among the biotic factors, plant-parasitic nematodes (PPN) are important. They include Meloidogyne spp., Pratylenchus spp., Radopholus similis and Rotylenchulus reniformis. However, the information about the distribution, density and prominence of plant-parasitic nematodes and their interrelation with soil types is very scarce. Hence, the present comprehensive nematode survey was undertaken in the major turmeric-producing states of India: Tamil Nadu, Andhra Pradesh, Telangana and Odisha. The results indicated that Meloidogyne spp., R. reniformis , Pratylenchus spp., R. similis , Hoplolaimus spp., Helicotylenchus spp. and Tylenchorhynchus spp. were associated with turmeric. The most abundant nematodes were Meloidogyne spp. (115 individuals (100 cm3 soil)−1), followed by R. reniformis (68 (100 cm3 soil)−1) and Pratylenchus spp. (50 (100 cm3 soil)−1). The frequency of occurrence ranged from 0 to 60%, with Meloidogyne spp. (60%) and R. reniformis (51%) being the most common. Meloidogyne spp. (38%) and Pratylenchus spp. (19%) were the most prominent nematodes in plant samples. Overall, Meloidogyne spp. followed by Pratylenchus spp., R. reniformis and R. similis were the key nematodes associated with the turmeric crop in all the four states. Further, we have identified hotspot areas for the plant-parasitic nematodes, namely: Meloidogyne spp. (16), Pratylenchus spp. (16), R. reniformis (20), and R. similis (5) on the basis of the economic threshold level. The interrelationship of soil type and nematode distribution was also investigated. [ABSTRACT FROM AUTHOR]

The River Ganga produces a substantial amount of its fish from small native species, defined here as those with a maximum length of 25 cm. The FiSAT program was utilized to estimate stock assessments of four important small indigenous species from the River Ganga: Johnius coitor, Cabdio morar, Salmostoma bacaila, and Gudusia chapra. Fish samples were collected monthly for a year (April 2020–May 2021) from four predetermined sampling sites along the River Ganga (Farakka, Berhampore, Balagarh, and Tribeni) in West Bengal, India. The estimated exploitation rate for Johnius coitor, Salmostoma bacaila, and Gudusia chapra was relatively lower than the optimum level of 0.5 and considerably lower than Emax values, indicating that their stocks are experiencing low fishing pressure in the region. The FiSAT results indicated that the species Cabdio morar was found to be heavily exploited. The total mortality (Z), natural mortality (M), and fishing mortality (F) rates for all four of the SIF species were examined, and they were contrasted with data from previous studies. On the lower stretch of the River Ganga, all of the fish stocks are optimally exploited (Eopt), except for the species Cabdio morar. The population dynamics of all of the species have been described for the first time on the lower stretch of the River Ganga. According to the findings, all of the fish stocks throughout the lower stretch of River Ganga are optimally exploited (Eopt), except for Cabdio morar. The study also emphasizes the importance of increasing sustainable fishing efforts, focusing on SIFs throughout the lower stretch of the River Ganga in order to safeguard the livelihood and nutritional status of fishermen. [ABSTRACT FROM AUTHOR]

Estimating home range size is an important aspect of ecological studies that helps in understanding species biology. The myrmecophagous sloth bear (Melursus ursinus) is one of the least studied large carnivores and is found in the Indian subcontinent with India being its stronghold. Despite its wide distribution in India, only one study has estimated its home range. In this study, we estimate the home range of a sloth bear using location data obtained through camera-trapping in Bannerghatta National Park in southern India during 2019 and 2020. A sloth bear was identified based on a unique marking on its pelage that was possibly caused by a wire snare. Using the minimum convex polygon and 40 camera-trap encounters, we estimated its home range to be ∼58 km2. Although camera-trapping was conducted to understand the population dynamics of leopards (Panthera pardus pardus), the data provided opportunistic information on nontarget species. Such byproduct data should be utilized to enhance our knowledge on various aspects of species biology. [ABSTRACT FROM AUTHOR]

In the present study, the dynamics of built-up and population, and the distribution of the road network were investigated to assess the efficiency of land consumption in the Hyderabad Metropolitan Area (HMA) between the years 1975 and 2015. Statistical techniques, geographic information systems (GIS), and causation analysis have been adopted to quantify and study land consumption efficiency. For this purpose, the built-up and population data are obtained from the Global Human Settlement Layer (GHSL) and road network maps are obtained from the OpenStreetMap (OSM) data set. To assess land use efficiency (LUE), the methodology provided in "SDG 11.3.1. Metadata" is adopted. From the results, it is evident that the average accuracy of the GHSL population layer between the years 1990 and 2015 was more than 90% and the absolute percent error of the GHSL population layer decreased with time. It was also observed that between 1990 and 2015 the HMA was stably moving toward sufficient land per person. Through correlation analysis, it was identified that there exists a very strong correlation between built-up, population, and road network density. The causation analysis using a novel coefficient of causation affirmed that changes in built-up and population are both caused equal changes on their counterpart and the built-up and population both influenced the changes in the road density of the HMA. From the findings of the current article, it is evident that the correlation and the causation analysis together give a clear understanding of the built-up and population dynamics. [ABSTRACT FROM AUTHOR]

Habitat suitability difference between sexes results in sex-specific dispersal. Although this behaviour is one of the key factors in understanding population dynamics, there are limited studies to evaluate it in arboreal species. We studied the distribution of the Indian Giant Squirrel (IGS; Ratufa indica maxima) from a sex perspective. We also evaluated potentiallly suitable habitat types for the species in the Nelliyampathy Reserve Forest, Western Ghats, Kerala, India. We used the sweep survey method to record the distribution pattern of squirrels and analysed the influence of climatic layers and other variables on the distribution using MaxEnt. The study revealed that there was a difference between the sexes in habitat selection. Males preferred more land-use types than females, which were restricted to only certain land-use types. Some of the major factors that determined the distribution of species were distance from urban settlement (50.1%), distance from shade plantation (23.2%), distance from rocky outcrop (9.2%), minimum temperature of the coldest month (9%) and precipitation of the wettest quarter (8.5%). The final MaxEnt model output predicted 49.07% suitable habitat for IGS, of which 45.47% and 34.42% were suitable for males and females respectively, with an overlap of 30.82% between the sexes. We suggest that it would be important to include a sex perspective in species habitat suitability studies in order to gain insights into sex-related habitat specificity and its role in dispersal. [ABSTRACT FROM AUTHOR]

Simple Summary: Cotton leafroll dwarf virus (CLRDV) can cause yield loss of cotton in susceptible plants. The only known aphid vector in the U.S. is Aphis gossypii, which regularly infests cotton, but knowledge so far is limited to the cotton growing season. Seven other species are also known to feed on cotton, but little is known about their seasonal dynamics. Two species are known vectors of CLRDV in chickpea in India. Improving our understanding of the viral spread and seasonal dynamics of potential vectors is key to developing management strategies for plant pathogens. In this study, we monitored seasonal population dynamics of these eight species, in three locations and two different habitats in Alabama, with the use of pan traps, year-round, for two consecutive years. To coordinate this with viral presence, CLRDV spread was monitored at the same sites with the use of cotton sentinel plants. Plants (while conditions allowed) and traps were collected and replaced weekly. Our findings provided baseline information on when these eight species are dispersing in the landscape and when CLRDV spread is occurring in cotton. While A. gossypii is likely the primary vector, early season spread of CLRDV suggests additional aphid vectors are possible. Cotton leafroll dwarf virus (CLRDV) is an introduced Polerovirus (Family: Solemoviridae) of cotton, Gossypium hirsutum L., in the U.S. The only vector known to transmit this virus to cotton is the cotton aphid, Aphis gossypii Glover; however, there are seven other species of aphids (Hemiptera: Aphididae) reported to colonize cotton in the southeastern U.S.: Protaphis middletonii (Thomas), Rhopalosiphum rufiabdominale (Sasaki), Aphis craccivora Koch, Macrosiphum euphorbiae Thomas, Myzus persicae (Sulzer), Smythurodes betae Westwood, and Aphis fabae Scopoli. Little to no information is available on annual population dynamics of these species in the southeastern U.S. The timing of CLRDV spread to cotton plantings is also unknown. The objective of this study was to monitor the population dynamics of eight cotton-feeding aphid species concurrent with the spread of CLRDV at three different locations in Alabama. Aphids were monitored weekly for two years with yellow pan traps, and sentinel plants were deployed weekly to monitor CLRDV spread throughout the cotton-growing season. During the two years, most CLRDV spread at all locations occurred when A. gossypii was actively dispersing in the field. Early season spread at sites in south and central Alabama, when A. gossypii was not abundant, suggests additional aphid vectors are possible. [ABSTRACT FROM AUTHOR]

Debt bondage is one of the most widespread forms of unfree labour today. The majority of the existing studies focuses on bonded labourers as a homogenous group rather than examining group dynamics within the population of bonded labourers. This paper tries to overcome these limitations and examines experiences of women bonded labourers from the Sahariya tribe in India. It argues that gendered norms intersect with other patterns of structural violence creating a situation where women are doubly exploited but also opening new (limited) agentic spaces for these women. [ABSTRACT FROM AUTHOR]

An HIV/AIDS transmission model is constructed and analyzed that assimilates spontaneous change in human behavior depending on the disease prevalence incorporating self‐shielding mechanism and treatment control. It is assumed that human population become aware of HIV disease from exposed environment and are conscious enough to make their knowledge fruitful by adopting self‐protective measures to reduce disease transmission. We introduce Hill type of behavioral change function and an awareness‐induced transmission function associated with nonlinear infection rate. We emphasize the effectiveness of human awareness in controlling HIV epidemic by investigating the impact of nonlinear incidence rate. Further, an optimal control model is formulated and solved to find the strategy of applying treatment considering spontaneous response of people towards HIV disease. In the numerical simulation segment, impacts of significant parameters have been assessed using sophisticated techniques. We calibrate the proposed model with the real data of HIV cases in India and estimate some crucial model parameters. Moreover, different amalgamations of preventive and treatment controls are introduced. The optimal treatment control has massive impact in curbing HIV epidemic. Also, combined strategy of prevention and treatment can curtail the disease with economic gain. It reveals that effective response of individuals can suppress the disease in such an unexpected situation when treatment rate is low. Increasing the efficacy of human consciousness is much beneficial in curbing HIV outbreak. Thus, our findings highlight a path to control HIV epidemic with uninstructed modification of human behavior by boosting up the productivity of their existing knowledge. [ABSTRACT FROM AUTHOR]

The ecological variation in biological and adult life‐table attributes of two populations of Aedes aegypti (Diptera: Culicidae) from the desert (Jodhpur) and coastal (Kolkata) regions of India are assessed to understand the reproductive and survival strategies. The results showed that females lived longer than males in both strains. The desert strain was more r‐strategist because of its higher intrinsic rate of increase (rm = 0.23), finite rate of increase (λ = 1.25), lower life expectancy of males (7.9 days) and females (14.4 days), mean generation time (T = 19.2 days) and doubling time (DT = 3.0 days). However, there was no difference in net reproductive rate (R0) between the desert and coastal strains. The coastal strain showed a longer female life expectancy (22.0 days) than the desert strain (14.4 days). However, the fecundity (eggs/female/day) was lower in the coastal strain (11.4) than in the desert strain (15.1). Conclusively, the desert (Jodhpur) strain is adapted to a better r‐strategy than the coastal (Kolkata) strain of Ae. aegypti, which might be helpful to flourish in harsh environmental conditions. This study may provide accurate predictions of Ae. aegypti population dynamics for vector management. [ABSTRACT FROM AUTHOR]

Despite their high dietary and behavioural flexibility, leopards have lost > 70% of their historic range due to the causes like habitat loss, prey depletion and poaching. Precise abundance estimates are among the essential information required for leopard conservation. We provide estimates of leopard population density from Gir Protected Area, Gujarat, India, using camera traps deployed from May to June 2017. Our survey consists of 50 sampling sites covering an area of 200 km2 in the western part of Gir. We used the likelihood—based spatially explicit capture-recapture (SECR) framework to assess leopard density in Gir. We identified 39 unique leopard individuals, among which 21 were males, 15 were females and three were of unknown sex. SECR analysis found the leopard density in Gir to be 19.90 ± 3.38 (S.E.) individuals/100 km2, where females had higher detection probabilities (0.14 ± 0.05 (S.E.)) than males (0.09 ± 0.02 (S.E.)). Males had a larger sigma value (σ) (in meters) (953.90 ± 92.99(S.E.)) than females (675.80 ± 84.78 (S.E.)). Possible reasons for the reported high leopard density are stringent protection measures which rule out chances of additive mortality in leopards, high preferred prey density, and limited effect of competitive interactions with Asiatic lions. A very high density of leopards could have implications for their own population regulation, prey population dynamics, and maintenance of the leopard population in the surrounding area through dispersal. The present study holds the potential to act as a baseline for future monitoring and inform management strategies for leopards in Gir. [ABSTRACT FROM AUTHOR]

The shot hole borer (SHB), Xylosandrus compactus (Eichhoff) (Coleoptera: Curculionidae: Scolytinae), is an emerging pest of Robusta coffee in India. Traps with attractants are commonly used to capture the ambrosia beetles for purposes of monitoring, studying population dynamics, predicting outbreaks, and mass trapping to reduce damage. The relative attractiveness of several common attractants and the influence of their concentration were evaluated in the field against X. compactus using Broca traps in this study. The tested attractants exhibited clear differences in attractiveness and the preliminary field studies at coffee plantations revealed that absolute ethanol attracted more shot hole borer adults than coffee twig extracts, distillery ethanol, and ethanol methanol combinations. The number of beetles trapped varied in different places during multi-location field trials, but in general, 50% of absolute ethanol-baited traps captured the highest number of beetles in all the locations. This study demonstrates 50% absolute ethanol can be used as an effective attractant for coffee shot hole borer and enables a cost-effective option for the control of X. compactus in coffee. [ABSTRACT FROM AUTHOR]

Mirid bug has become challenging pest infesting bottle gourd crop at Haryana state and Delhi NCR region in India. The feeding punctures caused on fruits due to bugs appears to be light reddish brown spots/blister, leading to blemished fruits which often fail to fetch a good market price. In the present study, we have endowed the species diagnosis (morphological and molecular), population dynamics, biology, fruit damage intensity and ecofriendly management of mirid bugs in bottle gourd crop. From the morphological studies it was found that, the mirid bug so investigated was found to be the zoophytophagous plant bug, Nesidiocoris tenuis (Reuter) (Hemiptera: Miridae). In addition, the molecular analysis (DNA Barcoding) also confirmed the species identity with the DNA sequence generated (Accession No. OM117590) matching up to 99.86% with that of the available relative sequences with a total branch length of 0.10 base substitutions per site in the phylogenetic tree. Across the fields surveyed, it was found that on an average the maximum abundance of N. tenuis was noticed at tender tip of vines (7.0 bugs per tender tip of vine) followed by fruits (4.9 bugs per fruit) and leaves (4.1 bugs per leaf). There were two peak incidence of N. tenuis noticed during the study. First peak during 21st SMW (4th week of May) (8.7 bugs per leaf and 12.7 bugs per tender tip of vine) and second peak during 24th SMW (3nd week of June) (7.3 bugs per leaf, 10.5 bugs per tender tip of vine and 5.7 bugs per fruit). During the study, it was found that the maximum temperature, mean temperature and sunshine hours showed significant positive relationship with N. tenuis population on leaves (r = 0.800, 0.560 and 0.770, respectively), tender tip of vine (r = 0.880, 0.550 and 0.780, respectively) and fruits (r = 0.801, 0.553 and 0.549, respectively). In the present investigation it was found that N. tenuis successfully completed its life cycle on bottle gourd plants with total life cycle duration of ~ 34 days. The mean fecundity was observed to be 10.8 eggs. The age-stage specific survival rate (Sxj) and life expectancy (Exj) studies revealed that the survival rate and life expectancy of adult females was higher than that of adult males of N. tenuis. The % fruit damage due to N. tenuis ranged between 61.90 – 73.68% and damage intensity ranged from 20.4 to 27.4 numbers of damage punctures per 2 cm2 area of fruit rind. Due to bagging of fruits, there was 67.60% reduction in fruit damage and 96.05 – 98.61% increase in number of marketable fruits which clearly envisage the farmers to adopt bagging technique in bottle gourd against N. tenuis to obtain quality fruits with higher economic yield. [ABSTRACT FROM AUTHOR]

The Sundarbans mangrove is a transitional zone between terrestrial land and sea, a unique location in our global geography. This study identifies the richness and population dynamics of bacterial populations along different seasons in the rooted and unrooted regions of soil sediments in Sundarbans, West Bengal. Throughout the year, bacterial populations were higher in the rooted sediment zone, than the unrooted area. The rooted zone contains more silt and clay but the unrooted zone harbours more silty, sandy soil. Salinity is lower in the unrooted zone. The heterotrophic bacterial populations were higher than other types of bacteria in both regions irrespective of seasonal variation. The results revealed that the most varied seasons were the monsoon season in the rooted and unrooted sediment region. The changes identified in this study were most likely due to variances in the microhabitat associated with mangrove root, physicochemical parameters and seasonal fluctuations. [ABSTRACT FROM AUTHOR]

Migratory shorebirds that move across continents along their flyways are undergoing a drastic decline globally. A greater proportion of them that regularly winter along the Indian coasts within the Central Asian Flyway (CAF) are also undergoing severe declines. However, the mechanisms underlying the population trends in these areas remain little understood. This study investigated the diversity, abundance, population dynamics and distribution patterns of shorebirds along the Indian coasts based on the available literature. The west coast of India is relatively less studied than the east coast in the CAF. Further, we observed that the diversity, abundance, population dynamics and distribution pattern of the shorebirds follow different trends on the west coast compared to the east coast. These variations are in accordance with the differences in topography and biotic and abiotic factors between the coasts. Anthropogenic activities have far-reaching effects on the survival and persistence of shorebirds along the coasts. The west coast is evidently more productive than the east coast at every trophic level and thus the west coast is expected to account for more abundance and diversity of shorebirds. Paradoxically, we found that the east coast supports a greater abundance and diversity of shorebirds than the west coast. The west coast, therefore, requires further investigations to obtain a better understanding of the causes of apparent differences in abundance and diversity as well as the observed declines in shorebirds, compared to the east coast of India. [ABSTRACT FROM AUTHOR]

The fall armyworm (FAW), Spodoptera frugiperda (J. E. Smith), was first detected in India in 2018 and seriously threatened the maize crop. In South India, we studied the population dynamics of FAW moths and the damage caused by the larvae in maize fields from 2019 to 2020. In the kharif season, the highest male moth catches occurred in July while in rabi season, the highest catches occurred in November. It was found that the early whorl stage (EV-V6) of maize crop was susceptible to FAW due to its high larval load, whereas the late whorl stage (V7-VT) of the crop showed greater leaf damage in both years. [ABSTRACT FROM AUTHOR]

Natural regeneration potential is an important indicator for any forest ecosystem and Andaman Padauk (Pterocarpus dalbergioides) is the principal timber tree endemic to Andaman & Nicobar Islands. This study analyzed the natural regeneration potential of Andaman Padauk under different disturbance regimes across its distribution range with regard to population dynamics, growth pattern, population structure, population status and allometry. Contrary to the perception that it is a poor regenerator, the species showed a luxuriant growth. While ephemerals, seedlings, saplings, poles and total regenerates are significantly high at the leading edge of its habitat, trees are significantly high at the trailing edge. Their heights are mostly positively skewed and normally distributed. With a reverse-J shaped demography, the species is in its most dominant form in the stand. Though its population status is declining, the prospects of population stabilization are high. There exists a strong proportionality between DBH and height of regenerates. Hence, the species should be assisted through considered disturbance to realize its natural regeneration potential. As all the species under the pantropical Pterocarpus genus share a number of growth and reproductive traits, the path breaking findings of this study emanated from refined methodologies will help assess the natural regeneration potential of other species whose existence is threatened by either unstable or declining population in their habitat. [ABSTRACT FROM AUTHOR]

The mango crop suffers a significant loss because of its infestation by mango leaf hoppers. Both nymphs and adults of mango hoppers cause severe damage to the mango plants at the flowering and fruiting stages. The damage is done mainly through the sucking of sap by the nymphs and adults of hoppers from the young soft leaves, shoots, and inflorescence, resulting in low crop yield and enormous economic loss to the farmers. The review aims at the seasonal incidence of mango leaf hoppers. [ABSTRACT FROM AUTHOR]

India has a rich source of biodiversity of medicinal plants, which serves as a source of livelihood for a large Indian population. For the past several decades, most of the research works on medicinal plants have been focused on isolating their active ingredient and preparing a suitable commercial formulation while completely neglecting their conservation. Very few studies have been done to understand the factors, especially biotic ones that limit the yield of medicinal plants. Therefore, the present study aims at studying the nature of the damage, severity of the injury, and population dynamics of Aphis nerii and its natural enemy (Cheilomenes sexmaculata) on madhunashini, Gymnema sylvestre at ICAR-Directorate of Medicinal and Aromatic Plants Research, Anand (Gujarat) India along with the study of weather parameters affecting pest population during two years from 2018–20. The percent incidence and severity of A. nerii ranged from 0 to 100 percent and 0 to 4, respectively. The peak population (275.56 and 293.31/10 cm twig) was recorded at the 6th SMW (Standard Meteorological Week) in both the observed years. The occurrence of C. sexmaculata started during the first fortnight of November, and peak population was recorded during the 6th SMW. During the study period, the aphid population was negatively correlated with all the density-independent factors. The different concentrations of neem oil (10000 ppm) like 0.25, 0.50, and 0.75 percent were used to test the efficacy during the peak insect activity period. Our study suggests that neem oil spray (10000 ppm) @ 0.75 percent could effectively manage the aphid population in field conditions. [ABSTRACT FROM AUTHOR]

Modelling in ecology and evolution, especially in India, is often done by researchers trained in physics or engineering without much experience of studying living systems. This is partly driven by a fallacious conviction that modelling is largely about mathematical skills and that, consequently, modellers can equally effectively apply their skills to problems in fields as diverse as physics/engineering and ecology/evolution. I discuss why this fallacy arises, and the many ways in which modelling in ecology or evolution is actually a very different endeavour from that in much of physics, even though the form of the equations deployed across disciplines is typically quite similar. Since modelling is not primarily about the mathematics but about the system being studied, I believe that a reasonable degree of comfort with models and modelling is important for those researchers in ecology and evolution who primarily undertake empirical studies, whether in the laboratory or the field. Equally, I suggest that researchers doing modelling in ecology and evolution, who were trained in the mathematical or physical sciences, need to understand the systems they attempt to model and also appreciate how modelling ecological and evolutionary processes differs from much of the modelling done in classical physics and allied fields. I also discuss what models are, whether modelling is subjective or objective, and what modelling entails if it is to meaningfully add to scientific understanding. This article is aimed primarily at young researchers interested in ecological and evolutionary questions, whether coming from a background in the biological or physical/mathematical sciences. [ABSTRACT FROM AUTHOR]

Ø Bactrocera dorsalis, Zeugodacus cucurbitae and Zeugodacus tau were the predominant fruit fly species during the snake gourd fruiting season. Ø Maximum species diversity and evenness estimates were registered by Methyl Eugenol traps. Ø Species richness estimates for Cue Lure and Methyl Eugenol traps during the entire experiment are analogous. Ø The rate of fruit fly infestation varied from 6.93 % to 44.09 %. Ø This study has proven the beneficial effect of trapping on the benefit cost ratio of snake gourd cultivation. A monitoring survey was conducted in snake gourd agro ecosystem during the fruiting season at Gangnapur, West Bengal, India to generate extensive data on fruit fly diversity, population dynamics, infestation rates and evaluate the effect of trapping on fruit fly infestation rates vis-à-vis benefit cost ratio of snake gourd cultivation. Methyl Eugenol and Cue Lure traps were used to assess the fruit fly species diversity. The number of adult male flies trapped was used to calculate fruit fly per trap per day and assess the population dynamics. Bactrocera dorsalis, Zeugodacus cucurbitae and Zeugodacus tau were the predominant fruit fly species during the fruiting season. Maximum species diversity and evenness estimates were registered by Methyl Eugenol traps. Species richness estimates for Cue Lure and Methyl Eugenol traps during the entire experiment are analogous due to the trapping of two different types of fruit fly species. Zeugodacus cucurbitae is the most abundant species in the snake gourd ecosystem and dominated the community of fruit flies throughout the study. Fruit fly per trap per day values indicated that the Gangnapur area is at infestation level, for Zeugodacus cucurbitae and Bactrocera dorsalis, while, for Zeugodacus tau the area is at suppression level. The rate of infestation varied from 6.93 % to 44.09 %. Farmers with traps in their fields reported a benefit cost ratio of 0.73 to 4.63, while the no-trap group reported 0.34 to 1.56. This study at Gangnapur has proven the beneficial effect of trapping on the benefit cost ratio of snake gourd cultivation. [ABSTRACT FROM AUTHOR]

Phaseolus vulgaris—Colletotrichum lindemuthianum is one among the oldest host and pathogen interface. Researchers have taken painstaking efforts across the world for understanding the dialogue during early and late phases of interaction. Collectively, these efforts resulted in the deluge of information that helped the researchers to underpin the interface. The latest molecular biology techniques furnished novel detection methods for the anthracnose pathogen, refined the understanding of pathogen population dynamics, and provided the insights on co-evolutionary common bean resistance and C. lindemuthianum virulence dynamics. One of the important breakthroughs came when the Phaseolus vulgaris and its corresponding anthracnose pathogen (C. lindemuthianum) genomes were decoded in 2014 and 2017, respectively. Availability of both the genomes yielded a significant genomic information that helped bean communities to fine map the economically important traits and to identify the pathogenicity determinants and effector molecules. The interface is in a continuous development as knowledge of the anthracnose resistance genes, their precise physical locations, and the identification of effector proteins; the fungus arsenals are being routinely updated. Hence, we revisited the interface and tried to provide an overview of host pathogen dialogue in the genomic era. Additionally, we compiled the sporadic information on this pathosystem from India and provided its futuristic road map to shape its research in the world and northern India, the major dry bean area in the country. [ABSTRACT FROM AUTHOR]

Cyprinus carpio, Oreochromis niloticus and Clarias gariepinus are the most abundantly captured invasive fish species in the mid-stretch of the Ganga river. Fish yield and biomass data based on mean abundance by weight was calculated using algorithms and spatio-temporal population dynamics model for future prediction of these invasive fish species. Temporal biomass forecast based on mean abundance by wieght for the period from 2020 to 2029 was determined. The findings of this study predicted fish yield of 176 ±16.33 kg km-1 day-1 C. carpio and 55.43 ± 6.4 kg km-1 day-1 O. niloticus during 2029 which might result into 117.87% and 116.9% rise in temporal biomass of Common Carp and Tilapia respectively in a decade's time while 139.2% rise in temporal biomass was predicted for the invasive African catfish. The yield of invasive Common Carp, Tilapia and African Catfish was correlated with rainfall and temperature data using ANOVA and we found that variance was F=1.36; p=0.263 for C. carpio; F=1.60; p=0.326 for O. niloticus and F=1.63; p=0.101 for C. gariepinus, indicating that variance was very close for Tilapia and African Catfish. The observed values of variance indicated that climatic changes had more impact to these two species than to the Common Carp. The concrete and forecast values were calculated considering 95% lower and upper level of confidence, which was significant (p<0.05) and the annual regression was found to be p<0.464, p<0.419 and p<0.499 for C. carpio, O. niloticus and C. gariepinus, respectively. Further, interactive performance of invaded C. carpio, O. niloticus and C. gariepinus was also assessed for understanding invasion meltdown. The results of mean abundance by weight based yield forecast of invaded Tilapia, Common Carp and African Catfish for the period of 2020 to 2029 suggest a stable production in the Ganga River in years to come. It also manifests a positive pattern of invasion in the times of climate change displaying invasion meltdown. This suggests increased pressures of fish invasions on temporal and spatial scales, and imposing new management challenges for freshwater ecosystems. [ABSTRACT FROM AUTHOR]

A pest scout data in pigeonpea (leaf webber, plume moth, pod borer) and chickpea (pod borer) crops including daily insect pest counts for three successive seasons (2015/16—2017/18) at western and eastern plateau hills (agro-climatic zones) of India was analysed for spatio-temporal dynamics. Longer infestation (different crop phenological growth stages) behaviour of leaf webber and pod borer in pigeonpea and chickpea, respectively influenced their increased mean counts (incidence). Weekly mean counts of leaf webber, plume moth and pod borer in both the crops varied significantly between the seasons. Linear incremental change in mean counts of leaf webber and pod borer on pigeonpea and chickpea, respectively was observed across the seasons (inter-seasonal). Intra-seasonal built-up of plume moth (pigeonpea) and pod borer (pigeonpea and chickpea) mean counts was also noticed. On pigeonpea, leaf webber and plume moth mean counts never reached an economic threshold level (3 larvae/plant), but crossed the advisory level (1.5 larvae/plant). It was observed that there was incremental rise in pod borer mean counts and crossing economic threshold level over seasons in chickpea (1 larvae/m row length), while it was not the case in pigeonpea (1 larvae/ plant). Furthermore, survival and management strategies of leaf webber, plume moth and pod borer in pigeonpea and pod borer in chickpea were discussed. [ABSTRACT FROM AUTHOR]

• Observed drastic declines in the abundance of kingfishers during 2010–2020 in wetlands in southwest India. • Shifts in environmental variables influenced abundance of kingfisher population. • Declining kingfishers indicate deteriorating wetland habitats. • Development and implementation of tailored conservation plans are imperative. Fragile wetland habitats are susceptible to multiple threats from anthropogenic activities. Direct waste deposition, habitat modification and overexploitation of fish have caused alternations in food webs in wetlands. Kingfishers are ecological indicators with the potential ability to respond to the minute changes in their microenvironment. Their abundance and distribution at wetland habitats are affected by multiple environmental factors. We studied the kingfisher assemblages in India to determine proximate and ultimate causes of their decline. We recorded the abundance of five species of kingfishers across five wetland habitats from 2011 to 2020 in Kerala, southwest coast of India. Kingfishers were counted twice in a month between 6.00 and 12.00 hrs. Air temperature, water temperature, humidity and turbidity were recorded. We measured fish diversity and abundance and organic waste as an additional explanatory variable. One-way ANOVA, Autoregressive Integrated Moving Average model and structural equation modelling were used to determine which explanatory variables affected kingfisher populations. Air temperature, water temperature and turbidity increased significantly during the study and had negative effects on the abundance of kingfishers. Humidity decreased significantly but had no effect on the kingfisher abundance. Fish abundance declined and had a strong positive effect on the abundance of kingfishers. The analysis of incidence of wastes across the study areas revealed that, all the sites were severely polluted. We also observed drastic decline in the abundance of all the species of kingfishers studied across the sites with a rapid decline in Pied Kingfisher and slower decline in White-throated Kingfisher. Black-capped Kingfisher is a local migrant to the study areas and is already red listed and categorized as Vulnerable (VU). This study suggests that kingfisher assemblages are declining along with the health status of the habitat. Urgent action is needed to help in designing and implementing effective management strategies for the sustainability of wetlands in the region. [ABSTRACT FROM AUTHOR]

The Western Ghats of peninsular India is a highly sensitive and threatened ecoregion of exceptional freshwater ichthyodiversity. The present study investigated the growth, mortality and stock characteristics of Hypselobarbus thomassi, an endemic cyprinid fish from the Parappar Reservoir of Western Ghats, on the basis of the length‐frequency data collected during the period from 2009 to 2011. The growth parameters of this species were estimated using the FiSAT program, and the asymptotic length (L∞) and growth constant (K) being 476.79 mm and 0.39 year−1, respectively. The age at zero length (t0) was calculated as −0.0485 year−1. The longevity (tmax) and growth performance index (ϕ) were reported as 7.69 years and 2.95. The estimated total mortality (Z), natural mortality (M) and fishing mortality (F) were 1.65, 0.38 and 1.27 year−1, respectively. The relative yield per recruit (Y/R) analysis revealed the exploitation rate (E) at different levels as E0.1 = 0.36, E0.5 = 0.28 and Emax = 0.42. The current exploration level (0.77) is higher than the optimum exploitation rate (Emax = 0.42), indicating an overexploitation of the H. thomassi population. Accordingly, needed management measures should include restrictions on fishing gear mesh sizes, reduced fishing effort and declaration of closed seasons and sanctuaries to protect this threatened species. [ABSTRACT FROM AUTHOR]

Ectoparasitism has a damaging impact on the economy of goat production in India, but the factors influencing its distribution and dynamics are less explored. The present study was designed to investigate the influence of environmental factors like weather and air quality parameters on the occurrence of different types of ectoparasites in goats of two agro-climatic regions of India, viz. the Upper Gangetic Plain (UGP) and the Western Himalayas (WH). The prevalence survey for ectoparasitism among goats was conducted during the four distinct climatic seasons (winter, summer, monsoon, autumn) in both regions. The season-wise data of weather parameters (maximum and minimum temperature, relative humidity in morning and evening, sunrise and sunset time, mean daily temperature and relative humidity, daily variation in temperature and relative humidity, and day length) and air quality parameters (air quality index (AQI), particulate matter 2.5 μm (PM2.5), particulate matter 10 μm (PM10)) of both regions were analyzed in relation with the ectoparasitic prevalence pattern of corresponding regions. The results depict a noticeable correlation between the studied parameters and seasonal variation in the occurrence of each type of ectoparasites. This outcome on the interaction of studied parameters and ectoparasitism is intriguing and it opens a huge scope for future studies on the biometeorological aspects of host-parasite ecological interplay and evolutionary biology. The better understanding of climatological aspects of ectoparasite occurrences helps goat farmers in formulating appropriate timely intervention strategies for the economic control of ectoparasites, which in turn tackles ectoparasiticidal drug resistance and reduces threat of vector-borne diseases. [ABSTRACT FROM AUTHOR]

We studied ELEFAN based population parameters from length-frequency data for Harpadon nehereus collected from different landing centres along the west coast of India. We analyzed the size structure and estimated growth parameters, recruitment, mortality and exploitation rate using FiSAT-II software. The asymptotic length (L∞ = 366 mm), growth coefficient (K = 0.98 year-1), total mortality (Z=3.32 year-1), natural mortality (M=1.6375 year-1), fishing mortality (F=1.6825 year-1), growth performance index (Ø = 3.12) and exploitation ratio (E = 0.51) were worked out for the species. The exploitation ratios were computed as Emax = 0.661, E10= 0.568, E50= 0.345. The length at first capture (Lc50) was estimated at 163.44 mm. The present value of E was found close to appropriate fishing pressure on the stock and a further increase of fishing pressure is not recommended. [ABSTRACT FROM AUTHOR]

Oil palm leaf webworm, Acria meyricki Shashank and Ramamurthy (Lepidoptera: Depressariidae) is emerging as serious defoliator of oil palm, Elaeis guineensis Jacq. in India. It damages oil palm of all ages, from nursery to adult palms. A study was conducted in the laboratory to understand the biology and morphometrics of A. meyricki. Abundance and population dynamics of leaf webworm and its parasitoids were studied in oil plantations in Andhra Pradesh, India. Pest density (number of larvae / leaf) and parasitism rates of parasitoids were quantified. Influences of weather factors viz., maximum and minimum temperature, morning and evening relative humidity and rainfall on the abundance of leaf webworm and its parasitoids were assessed. A female moth laid about 101.60 eggs in its life time. The caterpillars developed through six to seven instars. Total life cycle completed in 32.9 days (egg to adult). Leaf webworm preferred to defoliate the older and intermediate leaves of the palms. Early stage caterpillars of feed on green parenchymatous tissues of the leaflets from under surface leaving a thin parchment like upper epidermis undamaged, while, the later stages defoliate the leaves. In severe cases, leaflets appear widely eroded, thus curling, bending and drying consequently to the pest infestation. The activity of the pest in oil palm plantations was limited to cooler months of the year i.e. October to March. Pearson Co-efficient of correlation analysis showed that minimum and maximum temperatures had significant negative effect on the development of pest population (larval density). Three parasitoids viz., Dolichogenidea (=Apanteles) hyposidrae (Wilkinson), Elasmus brevicornis Gahan and Brachymeria albotibialis (Ashmead) were identified during the study and their role in the pest population changes is discussed. Correlation analysis indicated that the parasitoids, D. hyposidrae and B. albotibialis were significantly and positively correlated with abundance of host larvae and pupae respectively. Results of feeding tests indicated that oil palm was the best host known of all species tested, with higher rate of larval pupation and adult emergence and the lower duration of time to pupation and adult emergence, which was followed by cocoa. The practical implications of this knowledge are discussed. [ABSTRACT FROM AUTHOR]

Invasion of armoured catfish, Pterygoplichthys spp., is a major threat to global aquatic biodiversity, and developing effective strategies for their control and eradication is both a concern and a research priority. A length‐based population assessment of invasive Pterygoplichthys pardalis in southern India, a hotspot for endemic aquatic biodiversity, indicated that rapid growth, high growth performance index and continuous recruitment have aided their successful invasion. Increasing fishing pressure on the adults is not adequate for population management, and only targeting young individuals (<30 cm) will result in overexploitation and population collapse. [ABSTRACT FROM AUTHOR]

The East African Indian (EAI) and Central Asian (CAS) lineages of Mycobacterium tuberculosis complex (MTBC) mainly infect tuberculosis (TB) patients in the eastern hemisphere which contains many of the 22 high TB burden countries including China and India. We investigated if phylogeographical, epidemiological and demographical characteristics for these 2 lineages differed in SITVIT2 database. Genotyping results and associated data (age, sex, HIV serology, drug resistance) on EAI and CAS lineages (n = 10,974 strains) were extracted. Phylogenetic and Bayesian, and other statistical analyses were used to compare isolates. The male/female sex ratio was 907/433 (2.09) for the EAI group vs. 881/544 (1.62) for CAS (p-value<0.002). The proportion of younger patients aged 0–20 yrs. with CAS lineage was significantly higher than for EAI lineage (18.07% vs. 10.85%, p-value<0.0001). The proportion of multidrug resistant and extensively drug resistant TB among CAS group (30.63% and 1.03%, respectively) was significantly higher than in the EAI group (12.14% and 0.29%, respectively; p-value<0.0001). Lastly, the proportion of HIV+ patients was 20.34% among the EAI group vs. 3.46% in the CAS group (p-value<0.0001). This remarkable split observed between various parameters for these 2 lineages was further corroborated by their geographic distribution profile (EAI being predominantly found in Eastern-Coast of Africa, South-India and Southeast Asia, while CAS was predominantly found in Afghanistan, Pakistan, North India, Nepal, Middle-east, Libya, Sudan, Ethiopia, Kenya and Tanzania). Some geo-specificities were highlighted. This study demonstrated a remarkable cleavage for aforementioned characteristics of EAI and CAS lineages, showing a North-South divide along the tropic of cancer in Eastern hemisphere–mainly in Asia, and partly prolonged along the horn of Africa. Such studies would be helpful to better comprehend prevailing TB epidemic in context of its historical spread and evolutionary features, and provide clues to better treatment and patient-care in countries and regions concerned by these lineages. [ABSTRACT FROM AUTHOR]

Fertility is one of the most important determinants of population dynamics that has the highest significant contribution towards population size and structure in the world. The study of human fertility is of the utmost importance in population studies. For the purpose of the study, a descriptive cross-sectional study was conducted through a field-work based data collection with 627 Bishnupriya married women who are in the reproductive age (15 - 49 years) and have at least one child in 601 households in the Ngaikhong Khullen village of Bishnupur District, Manipur. Factors were checked for association with total children ever born (TCEB) by using of chi-square test and binary logistic regression was applied to determine the effect of socio-demographic and economic factors on TCEB. The present study shows that the mother's age, age at marriage, and household income have a significant effect on the total number of children ever born at a significance level of 5%. [ABSTRACT FROM AUTHOR]

Presently, due to changing population dynamics and macro-economic reasons the social security program for the aged ones and the working classes in India is devoid of respect, compassion, and gratitude. In addition to the demographic pressure, the system is under strain and needs to be reform. Nowadays, there is also an increasing trend towards privatization of social security due to the rapid aging of the population and other socio-economic factors. Thus the social security agenda under the present system became confusing which again needs to be clarified. With the rapid transformation of social and economic structure, there is increasing pressure on the state to take suitable measures to provide social security with a focus on the elderly as well as the unorganized sector. Therefore the government agencies have to think twice to continue with the present system. [ABSTRACT FROM AUTHOR]

Studies on population dynamics and dominance of leafhopper species on 'Alphonso' mango were conducted from May 2016 to April 2017 at mango orchard of Agriculture College, Shivamogga and Doddabbigere village of Davanagere district, Karataka, India. Maximum population of leafhoppers was recorded during second fortnight of February 2017 (33.54 leafhopper / inflorescence) in mango orchard of Agriculture College, Shivamogga followed by first fortnight of February 2017 (29.98 leafhopper/inflorescence). Lowest number of leafhoppers was found during second fortnight of August 2016 (1.35 leafhopper / five sweeps in each direction). While at farmers orchard, the leafhopper population during first fortnight of February 2017 was highest (35.47/inflorescence) followed by first fortnight of January 2017 (34.49/inflorescence). Lowest leafhopper was found during first fortnight of September 2016 (2.05 leafhoppers/five sweeps in each direction). Irrespective of seasons in both the locations the overall per cent dominance of mango leafhopper species was highest in I. nitidulus followed by I. nagpurensis and A. atkinsoni. Correlation analysis with various weather parameters in both the locations indicated that, maximum temperature and minimum temperature showed significant positive, whereas morning relative humidity had significant negative correlation with the incidence of hoppers. [ABSTRACT FROM AUTHOR]

Okra production in the tropics is threatened by attack of insect-pests, fruit and shoot borer (FSB), jassid and whitefly causing severe loss in marketable yield particularly in the Gangetic plains of eastern India. No developed varieties/hybrids are free from attack of these pests. However, improved lines of okra have potential to broaden the genetic variability may improve resistance to these pests. Therefore, the population dynamics of these pests were recorded from 24 advance breeding lines/varieties of okra during peak infestation period over two consecutive years. Morphological leaf traits and biochemical parameters were assessed as potential mediators of resistance. The population of these pests reached above economic threshold levels during the month of September. Significant genotypic differences in terms of infestation of these pests were observed. Negatively correlated physico-chemical characters might be considered as important indices for selection of genotype tolerant to these pests. As indicated by the low infestations, the tolerance of BCO-1 to FSB, whitefly and that of Arka Anamika to jassid is based on both antixenotic properties of the genotypes. The donor parents BCO-1 and Arka Anamika should, therefore, be introduced into okra breeding programs to enhance tolerance against these pests. [ABSTRACT FROM AUTHOR]

Poverty affects many people, but the ramifications and impacts affect all aspects of society. Information about the incidence of poverty is therefore an important parameter of the population for policy analysis and decision making. In order to provide specific, targeted solutions when addressing poverty disadvantage small area statistics are needed. Surveys are typically designed and planned to produce reliable estimates of population characteristics of interest mainly at higher geographic area such as national and state level. Sample sizes are usually not large enough to provide reliable estimates for disaggregated analysis. In many instances estimates are required for areas of the population for which the survey providing the data was unplanned. Then, for areas with small sample sizes, direct survey estimation of population characteristics based only on the data available from the particular area tends to be unreliable. This paper describes an application of small area estimation (SAE) approach to improve the precision of estimates of poverty incidence at district level in the State of Bihar in India by linking data from the Household Consumer Expenditure Survey 2011–12 of NSSO and the Population Census 2011. The results show that the district level estimates generated by SAE method are more precise and representative. In contrast, the direct survey estimates based on survey data alone are less stable. [ABSTRACT FROM AUTHOR]

Aspects of population dynamics of Spinycheek lanternfish Benthosema fibulatum (Gilbert and Cramer 1897), caught off the south-west coast of India were studied. The asymptotic length (L∞) and growth constant (K) were estimated at 108 mm and 0.460 yr-1 respectively while tmax was worked out as 6 years. Benthosema fibulatum grows faster initially and attains a total length of 101.22 mm over 6 years. The coefficients of total mortality (Z), instantaneous natural mortality (M) and fishing mortality (F) were estimated as 2.32 yr-1, 0.51 yr-1 and 1.81 yr-1 respectively. The exploitation rate (E) was estimated as 0.78 yr-1. Size at first capture (Lc) was estimated as 62.84 mm TL. The relative yield per recruit reached maximum at an exploitation rate (Emax) of 0.772. Though there has been no targeted fishery for myctophids in the area of study, they constituted a significant proportion of bycatch of deep sea shrimp trawlers. Benthosema fibulatum stock may be unsustainable when fishery intensifies in future to meet demand from fish meal industry, unless proper action is taken to manage the stocks. [ABSTRACT FROM AUTHOR]

According to the United Nations Human Settlements Program (UNHSP), the number of slum households in developing countries continues to grow by a higher proportion as compared to its encompassing city. Traditionally, policy makers have concentrated on population control strategies by focussing on birth rates and rural–urban migration to stem the growth and emergence of slums. However, these strategies have often failed to achieve the desired results. In the present paper we find the key underlying processes that explains the observed differences in household life cycle between slum and non-slum households. We find that the slum households when compared to nonslum urban households, exhibit a large variation in the household size over the course of their life cycle, which in turn leads to inefficiency while building slum resettlement colonies. We have developed an agent based model, namely DynaSlum , to identify the key social determinants that impact the behaviour of a slum household. We use a novel and unique dataset based on the field work from 37 slums in Bangalore combined with the NFHS data to calibrate DynaSlum and validate our findings. This paper presents two major insights to address the challenges. First, we find that high rate of home leaving among young adults is the key determinants for the large variation in the life cycle of slum households. Second, we show that reducing home leaving among young adults will reduce the formation number of new slum households and contribute to a higher but stable household size. This will lead to efficiency and higher per capita resource consumption when building capacity for slum development (resettlement colonies) as policy makers would be able to plan for a stable household size. [ABSTRACT FROM AUTHOR]

The study was carried out (a) to identify the changes in the soil organic carbon (SOC) content during the different phases of slash-and-burn cultivation—i.e., before slash-and-burn (Phase 1), after slash-and-burn (Phase 2), and after harvest (Phase 3); and (b) to determine the status of soil organic carbon content in the primary undisturbed forest (Site 1) and in the secondary forests, where slash-and-burn cultivation was taken up ~25 yr (Site 2), 15 yr (Site 3), and 5 yr back (Site 4). The undisturbed forest holds the largest amount of SOC % (5.25) followed by 25 yr (3.07), 5 yr (2.86), and 15 yr (2.27) fallow. The mean percentages of SOC in the 0- to 15-cm layer fell from 3.07 in Phase 1 to 2.53 and 2.37, respectively, in Phases 2 and 3; in the subsurface 15- to 30-cm layer, they fell from 1.95 to 1.62 and 1.63, respectively. Although, the SOC in Phase 3 still seems sufficient to support another round of cultivation, further studies are needed to examine crop yields in successive cultivation cycles, suitability of other rice varieties, and weed and pest types and rates of invasion. Tribal population dynamics is another major concern, which needs assessment for monitoring future land requirements. [ABSTRACT FROM PUBLISHER]

Saltmarsh ecosystems though ecologically important are one of the least studied ecosystems in Asia. This study reviewed the published literature from 1988 to 2021 of India to assess the current status of the data deficient saltmarsh species Porterasia coarctata (Roxb.) within its distribution limits. This saltmarsh species inhabits the lower intertidal silty-sandy habitats of India's west coast and silty-clay habitats of the east coast. In the lower intertidal zone, P. coarctata is mostly associated with Myrostachia wightiana , whereas in the upper intertidal zone the highest chance of presence was for Suaeda maritima (18%) and the lowest for Cressa cretica (1%), S. fruticosa (1%) and Scirpus littoralis (1%). The deep root system of P. coarctata helps in sediment accretion and facilitates the formation of mangrove ecosystems. From this study it was evident that most of the research on P. coarctata in India was part of survey of mangrove ecosystems. In India, significant knowledge gap exists on the reproductive ecology and population trends of this species. Most importantly, the genes responsible for salinity and submergence tolerance of P. coarctata are well documented, that can provide solutions for salt and submergence tolerant rice plants in coastal areas prone to sea level rise. The blue carbon storage potential of P. coarctata is higher than other saltmarsh plants, that can be leveraged as a nature-based solution for CO 2 emission reductions. The ecosystem services of P. coarctata can also contribute towards achieving various sustainable development goals (SDG-1,2,6,13 and14). Coastal development, mangrove restoration and marine food provisioning are the most important drivers causing the decline of P. coarctata ecosystems across India. This study proposes a long-term coastal monitoring plan for essential conservation and management of existing P. coarctata beds and preventing further degradation and loss of these ecosystems. This study also showcases species-specific valuation of individual saltmarsh plants at regional scale are essential to catalogue the most efficient saltmarsh plants that can play an important role in future climate change scenarios and serve as a global model. • Porterasia coarctata is ecologically important saltmarsh species. • Genes responsible for salinity and submergence tolerance are well documented. • Carbon storage capacity of P. coarctata is higher than other saltmarsh species. • Coastal development and mangrove restoration are major cause of habitat loss. • P. coarctata can contribute towards achieving five Sustainable Development Goals. [ABSTRACT FROM AUTHOR]

This paper compares and contrasts the spread and impact of COVID-19 in the three countries most heavily impacted by the pandemic: the United States (US), India and Brazil. All three of these countries have a federal structure, in which the individual states have largely determined the response to the pandemic. Thus, we perform an extensive analysis of the individual states of these three countries to determine patterns of similarity within each. First, we analyse structural similarity and anomalies in the trajectories of cases and deaths as multivariate time series. Next, we study the lengths of the different waves of the virus outbreaks across the three countries and their states. Finally, we investigate suitable time offsets between cases and deaths as a function of the distinct outbreak waves. In all these analyses, we consistently reveal more characteristically distinct behaviour between US and Indian states, while Brazilian states exhibit less structure in their wave behaviour and changing progression between cases and deaths. • We compare and contrast the natural history of COVID-19 in the US, India and Brazil. • Case, death and mortality rate trajectories are analysed on a state-by-state basis. • We quantify heterogeneity and identify anomalous states therein within each country. • Wave behaviours are explored and clustered across the three countries states. • New mathematical methods quantify the lag in the progression from cases and deaths. [ABSTRACT FROM AUTHOR]

As reported India is having skewed sex ratio at birth. Sex ratio is one of the important demographic parameter to describe the population structure. Changes in sex composition largely reflect the underlying socio-economic, cultural patterns, demographic development and also gender relations of a society. In general, skewed sex ratio means the declining of the female population, while the declining of the male population could also be possible. The present paper reviews the sex ratio pattern of Manipur state in the last five census decades. The review points out the trend of decline of male population in the state and tries to visualise the problems from socio-political scenario. [ABSTRACT FROM AUTHOR]

Abstract: Dispersal is a life history trait that plays a key role in population dynamics. We used camera traps to estimate the distance male and female tigers (Panthera tigris) dispersed from Ranthambhore Tiger Reserve (RTR) in semi-arid habitats of western India from 2003 to 2010. We deployed camera traps whenever tiger tracks were found in places adjacent to protected areas where tigers had not been recently reported. We identified tigers by matching strip patterns by using their photographs with the database of camera-trapped tigers of RTR at the Wildlife Institute of India, Dehradun. We determined the aerial distance (straight line) between the last location of photo-capture in the natal area (in RTR) and the location of the most recent photo-capture. One female and three male tigers that dispersed from RTR were identified from photographs. The longest distance dispersed by a tiger was 148.4 km, and the average dispersed distance was 124.2 ± 23.7 km (n = 3) for male tigers and 78.4 km for the female tiger. The minimum age of the male tigers when they dispersed was 24 months. These data are important for making conservation and management decisions for restoration of potential connectivity between landscapes. [Copyright &y& Elsevier]

The abundance, population structure and other biological aspects of Siriella gracilis were evaluated based on zooplankton collections in the Exclusive Economic Zone of India (Arabian Sea, Bay of Bengal and Andaman Sea) as a part of a multidisciplinary project, Marine Research on Living Resources Assessment Programme. S. gracilis exhibited a wide range of variations in its population dynamics in the study area and the population density over the entire study area ranged from 0 to 29250 ind. per 1000 m3. The highest abundance was in the Arabian Sea (70.1% of the total sampled population) followed by the Andaman Sea (22.7%) and the Bay of Bengal (5.2%). Temperature and salinity appeared to have little influence on the general distribution of S. gracilis in the study area. The number of eggs/embryos carried by females exhibited a positive correlation with female size and the maximum brood size was 11. The egg diameter ranged from 0.32 to 0.46 mm and was independent of female size. Even though no significant body length difference was found between spent females and breeding females (p>0.05), wet mass of spent females and breeding females was significantly different (p <0.0001), obviously resulting from the added weight of the brood in ovigerous individuals. [ABSTRACT FROM AUTHOR]

Abstract: Most developing countries such as India use biomass as a primary source of energy especially in domestic sectors in the rural area. The increasing population exerts more pressure on the biomass resource thereby initiating energy crisis in the region. The issue of shortage of fuelwood in the remote mountain regions is increasing since the alternative energy resources have limitations either due to poor economic condition of the people, complex technology involved or being inaccessible due to remoteness. It is also seen that the use of traditional biomass as a source of energy will improve the livelihood conditions of the people and it will give ecological benefits to the region if other associated factors like health, gender etc. are taken care of and thus the planners aim to focus on sustaining the natural fuelwood resources. The present paper attempts to predict the future fuelwood demand based on the present consumption pattern in the upland villages of Indian Himalaya. Major consumption characteristics such as fuelwood consumption at different altitude and per capita fuelwood consumption (PCFC) are studied. Population dynamics model is postulated in order to assess future population vs. fuelwood consumption scenario, thereby projecting the future population and the future fuelwood demand in the region. It is observed that variations in fuelwood consumption exist at different altitudes in the hilly region. Mathematical modelling and time-series simulation model was proposed and validated model to predict the future expected demand of fuelwood resources in Phakot watershed. Based on the projected population and season based fuelwood requirements, the watershed will have a total fuelwood demand of 19,327t in 2011 which is expected to reach 36,462t in 2021. Such studies on the future resource demand trends will help in finding suitable region-specific and need-based alternative strategies for achieving sustainable fuelwood management at the micro-level. [Copyright &y& Elsevier]

The emergence of variety of land-use changes due to continuous anthropogenic pressure in peri-urban areas may concomitantly result in modification of the structure of associated plant communities for their sustainable growth. In the present study, plant diversity, and above- and belowground biomass distribution among species were investigated to understand their dynamics across different season, soil, and site conditions in a dry tropical peri-urban region in India. From four study sites that covered contrasting land uses: abandoned brick kiln (ABK), grazing land (GL), Kali river bank (KRB), and agricultural land (AL), a total of 360 monoliths were randomly extracted in three seasons, and dry weights were estimated for aboveground and belowground parts of species individuals. Seasonal soil samples of the sites were analyzed for physico-chemical characteristics. Of the total 87 recorded species that were mainly annual weeds and ruderals, 77% were forbs and 23% grasses. The ranges of plant biomass recorded across all sites and seasons were: aboveground 228-738 g m, belowground 83-288 g m, and a total of 344-1,026 g m. The dominance of species differed between above- and belowground; some species dominated only above- or belowground, and others dominated in both layers. Above- and belowground biomass of the sites, differential community-biomass allocation to above- and belowground parts and species dominants varied significantly with site and season. ABK and AL sites showed lower species diversity and soil nutrients compared to GL and KRB sites. Belowground biomass significantly declined with increasing soil organic C and total N, indicating altered dry matter allocation under resource-scarce habitat conditions. Higher diversity occurred at both low- and high-biomass sites, reflective of enhanced ability of these plant communities to exploit resources maximally in spatio-temporal pattern. [ABSTRACT FROM AUTHOR]

Hunting of hornbills by tribal communities is widespread in logged foothill forests of the Indian Eastern Himalaya. We investigated whether the decline of hornbills has affected the dispersal and recruitment of 3 large-seeded tree species. We hypothesized that 2 low-fecundity tree species, Chisocheton paniculatus and Dysoxylum binectariferum (Meliaceae) bearing arillate fruits, are more dispersal limited than a prolifically fruiting drupaceous tree Polyalthia simiarum (Annonaceae), which has potential dispersers other than hornbills. We estimated the abundance of large avian frugivores during the fruiting season along transects in 2 protected and 2 disturbed forests. We compared recruitment of the tree species near (<10 m) and far (10--40 m) from parent trees at protected and disturbed sites. Median abundance of Great (Buceros bicornis ), Wreathed (Aceros undulatus ), and Oriental Pied Hornbills (Anthracoceros albirostris ) were significantly lower in disturbed forests, but sites did not differ in abundances of the Mountain Imperial Pigeon (Ducula badia ). Overall, tree species showed more severely depressed recruitment of seedlings (77% fewer) and juveniles (69% fewer) in disturbed than in protected forests. In disturbed forests, 93% fewer seedlings of C. paniculatus were beyond parental crowns, and a high number of all seedlings (42%) accumulated directly under reproductive adults. In contrast, D. binectariferum and P. simiarum were recruitment rather than dispersal limited, with fewer dispersed seedlings surviving in disturbed than in protected forests. Results are consistent with the idea that disturbance disrupts mutualisms between hornbills and some large-seeded food plants, with the caveat that role redundancy within even small and specialized disperser assemblages renders other tree species less vulnerable to loss of regular dispersal agents. [ABSTRACT FROM AUTHOR]