Toxicity of saponin isolated from Gymnema sylvestre R. Br. (Asclepiadaceae) against Culex tritaeniorhynchus Giles (Diptera: Culicidae) Japanese encephalitis vector mosquito in India

O presente trabalho é para identificar a atividade larvicida de vários extratos da Gymnema sylvestre contra o vetor da encefalite japonesa, Culex tritaeniorhynchus em Tamilnadu, Índia. Com este propósito o princípio ativo presente na fração mais promissora foi obtida através de um extrato clorofórmio:metanol da fração 2. Os extratos das folhas do G. sylvestre foram testados empregando o procedimento da WHO contra estágios quaternários da larva do C. tritaeniorhynchus e as mortalidades larvais foram registradas após várias concentrações (6,25, 12,5, 25,0 e 100; 34,756 µg/mL (24,475-51,41), 31,351 µg/mL (20,634-47,043) e 28,577 µg/mL (25,159-32,308) g/mL); os valores de LC50 de 24 horas dos extratos das folhas de G. sylvestre foram determinados seguindo a análise Probit. Foi notado que o nível de tratamento de 100 µg/mL exibiu a mortalidade mais alta para os três diferentes extratos crus e foi significantemente diferente das mortalidades médias registradas para as outras concentrações. Os valores de LC50 de 34,756 µg/mL (24,475-51,41), 31,351 µg/mL (20,634-47,043) e 28,577 µg/mL (25,159-32,308) foram calculados para os extratos de acetona, clorofórmio e metanol com os valores de qui-quadrado de 10,301, 31,351 e 4,093 respectivamente. A presente investigação mostra que o G. sylvestre pode ser usado como componente importante no programa de controle do vetor.To determine the larvicidal activity of various extracts of Gymnema sylvestre against the Japanese Encephalitis vector, Culex tritaeniorynchus in Tamilnadu, India. To identify the active principle present in the promising fraction obtained in Chlorofom:Methanol extract of Fraction 2. The G. sylvestre leaf extracts were tested, employing WHO procedure against fourth instar larvae of C. tritaeniorhynchus and the larval mortalities were recorded at various concentrations (6.25, 12.5, 25.0, 50 and 100 µg/mL); the 24h LC50 values of the G. Sylvestre leaf extracts were determined following Probit analysis. It was noteworthy that treatment level 100 µg/mL exhibited highest mortality rates for the three different crude extracts and was significantly different from the mean mortalities recorded for the other concentrations. The LC50 values of 34.756 µg/mL (24.475-51.41), 31.351 µg/mL (20.634-47.043) and 28.577 µg/mL (25.159-32.308) were calculated for acetone, chloroform and methanol extract with the chi-square values of 10.301, 31.351 and 4.093 respectively. The present investigation proved that G. Sylvestre could be possibly utilized as an important component in the Vector Control Program

Floristic Diversity and Vegetation Analysis of Plants from Various Forest Types in Hosur Forest Division, Tamil Nadu, Southern India

The study deals with the floristic diversity assessment and vegetation composition analysis in various forest types from Hosur Forest division situated in Eastern Ghats of Southern India, in the state of Tamil Nadu. The study recorded 468 species of plants belonging to 283 genera and 91 families, including Angiosperms (464 species), Pteridophytes (3 species) and Bryophytes (1 species). Of the total, 94 species are trees, 12 are lianas, 70 are shrubs, 34 species are climbers, 194 species are herbs, sedges 7, grasses 21, ferns 3 and 1 species of moss. The five most abundant families in Hosur Forest Division were Fabaceae (45 spp.), Poaceae (34 spp.), Acanthaceae (30 spp.), Euphorbiaceae (28 spp.) and Rubiaceae (25 spp.). The quantitative features such as density and important value index (IVI) varied greatly among forest and in different forest types. In the present study, the diversity index of shrubs and herbs were found to be higher than that of trees. The maximum species diversity was recorded in Southern dry mixed deciduous forest (SDMDF) followed by Southern Thorn Forest (STF) and Southern Thorn Scrub (STS). The species diversity (H) was recorded the highest for SDMDF (5.61) followed by STF (5.18) and the lowest for STS (5.12). The presence of large number of higher girth class tree species and low number of sapling and seedling indicates that the present forests investigated are old and exhibiting low regeneration

Zooplankton fauna

The zooplankton population consists of minute animals living freely in water with limited powers of locomotion and is more or less drifted passively by water currents. Almost every major group of animals, either as adults, larvae or as both has its representatives in planktonic existence. Many of the commercially important prawns, mussels, other shellfishes and finfishes start their life as plankters. The communities of zooplankton form the vital intermediary link in the food chain of the sea both as consumers of the primary producers and as contributors to the higher trophic level. Many species are proven indicators of pollution, water mass, cold, warm, surface or deep waters, upwelling characteristics and of the coastal or estuarine environment depending on the time of their occurrence and the ambient ecological parameters

Floristic Diversity, Vegetation Analysis and Threat Status of Plants in Various Forest Types in Dharmapuri Forest Division, Tamilnadu, Southern India

The present paper deals with the study conducted to know the floristic diversity assessment and vegetation composition analysis in various forest types of Dharmapuri Forest division situated in Eastern Ghats of Southern India in the state of Tamilnadu. A total of 352 species of 233 genera and belonging to 79 families were recorded. The quantitative features such as density and important value index (IVI) varied greatly among forest and different forest types. In the present study the diversity index of shrubs and herbs were found to be higher than the tree species. The presence of high number of higher girth class of tree species and low number of sapling and seedling indicates that the present forest is old and exhibiting the low regeneration

Chickpea Genotypes Contrasting for Vigor and Canopy Conductance Also Differ in Their Dependence on Different Water Transport Pathways

Lower plant transpiration rate (TR) under high vapor pressure deficit (VPD) conditions and early plant vigor are proposed as major traits influencing the rate of crop water use and possibly the fitness of chickpea lines to specific terminal drought conditions—this being the major constraint limiting chickpea productivity. The physiological mechanisms underlying difference in TR under high VPD and vigor are still unresolved, and so is the link between vigor and TR. Lower TR is hypothesized to relate to hydraulic conductance differences. Experiments were conducted in both soil (Vertisol) and hydroponic culture. The assessment of the TR response to increasing VPD showed that high vigor genotypes had TR restriction under high VPD, and this was confirmed in the early vigor parent and progeny genotype (ICC 4958 and RIL 211) having lower TR than the late vigor parent and progeny genotype (ICC 1882 and RIL 022). Inhibition of water transport pathways [apoplast and symplast (aquaporins)] in intact plants led to a lower transpiration inhibition in the early vigor/low TR genotypes than in the late vigor/high TR genotypes. De-rooted shoot treatment with an aquaporin inhibitor led to a lower transpiration inhibition in the early vigor/low TR genotypes than in the late vigor/high TR genotypes. Early vigor genotypes had lower root hydraulic conductivity than late vigor/high TR genotypes. Under inhibited conditions (apoplast, symplast), root hydraulic conductivity was reduced more in the late vigor/high TR genotypes than in the early vigor/low TR genotypes. We interpret that early vigor/low TR genotypes have a lower involvement of aquaporins in water transport pathways and may also have a smaller apoplastic pathway than high TR genotypes, which could explain the transpiration restriction under high VPD and would be helpful to conserve soil water under high evaporative demand. These findings open an opportunity for breeding to tailor genotypes with different “dosage” of these traits toward adaptation to varying drought-prone environments

Character-based DNA barcoding for authentication and conservation of IUCN Red listed threatened species of genus Decalepis (Apocynaceae)

open access articleThe steno-endemic species of genus Decalepis are highly threatened by destructive wild harvesting. The medicinally important fleshy tuberous roots of Decalepis hamiltonii are traded as substitute, to meet the international market demand of Hemidesmus indicus. In addition, the tuberous roots of all three species of Decalepis possess similar exudates and texture, which challenges the ability of conventional techniques alone to perform accurate species authentication. This study was undertaken to generate DNA barcodes that could be utilized in monitoring and curtailing the illegal trade of these endangered species. The DNA barcode reference library was developed in BOLD database platform for candidate barcodes rbcL, matK, psbA-trnH, ITS and ITS2. The average intra-specific variations (0–0.27%) were less than the distance to nearest neighbour (0.4–11.67%) with matK and ITS. Anchoring the coding region rbcL in multigene tiered approach, the combination rbcL + matK + ITS yielded 100% species resolution, using the least number of loci combinations either with PAUP or BLOG methods to support a character-based approach. Species-specific SNP position (230 bp) in the matK region that is characteristic of D. hamiltonii could be used to design specific assays, enhancing its applicability for direct use in CITES enforcement for distinguishing it from H. indicus

Responsible Factors of Panic Buying: An Observation From Online Media Reports

Background: Panic buying is an erratic human behavior that has been reported irregularly and episodically. There is a dearth of studies exploring the identifiable factors accounting for it. We aimed to identify the factors responsible for panic buying extracted from online media reports. Methods: We scrutinized the media reports published in English discussing the different aspects of panic buying. We collected data until May 30, 2020, and searched the possible mentioned reasons responsible for panic buying. Results: We analyzed a total of 784 media reports. The majority of the reports were found in Bing (18%), Ecosia (12.6%), Google (26.4%), and Yahoo (12.5%). Panic buying was reported in 93 countries. Among the 784 responses, a total of 171 reports did not explain the responsible factors of panic buying. Therefore, we analyzed the remaining 613 reports to identify the same. A sense of scarcity was reportedly found as the important factor in about 75% of the reports followed by increased demand (66.07%), the importance of the product (45.02%), anticipation of price hike (23.33%), and due to COVID-19 and its related factors (13.21%). Other reported factors were a rumor, psychological factors (safety-seeking behavior, uncertainty, anxiety reduction, and taking control), social learning, lack of trust, government action, and past experience. Conclusions: The study revealed the responsible factors of panic buying extracted from media reports. Further, studies involving the individuals indulging in panic buying behavior are warranted to replicate the findings

Micro algae

The present work pertains to the micro flora of selected mangroves of India. The littoral diatoms are found to occur in the sediment as well as attached to the decaying leaves of mangrove plants. Few of them are true plankton, which are brought to the mangroves during high tide. Altogether 48 genera and 2 general of blue green have been described under which 80 species have been found in the Indian mangroves

Drug utilization evaluation of third generation cephalosporins using core drug use indicators

Abstract: To evaluate the drug utilization of third generation cephalosporins using core drug use indicators in various wards of Sri Ramachandra Hospital. Third generation cephalosporins are the most commonly prescribed broad spectrum antibiotic even before the culture sensitivity results arrives. Hence this study was undertaken to study the drug utilization evaluation of third generation cephalosporins in the inpatient department of various wards of Sri Ramachandra Hospital. A prospective study was conducted between July 2009 and February 2010. Prescriptions of 364 patients containing third generation cephalosporins admitted in inpatient department of various wards of Sri Ramachandra Hospital, Chennai were collected and using WHO basic drug indicators, the utilization pattern were analyzed. The average number of drugs per prescription was found to be 7.89 on prescription analysis. Cefixime was the most frequently prescribed (32.69%) oral third generation cephalosporins, followed by cefotaxime (31.32%). Among IV third generation cephalosporins, cefotaxime was the most frequently prescribed injections (35.4%). Only 28.02% of drugs were prescribed by generic name. The results obtained represent the over all prescribing pattern of third generation cephalosporins in the Tertiary Care Teaching Hospital, Chennai