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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]

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]

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]

Simple Summary: Malaria is a complex disease in part due to multiple vectors having different biological characteristics. In India, there are six primary vectors of malaria viz., Anopheles culicifacies, An. fluviatitlis, An. stephensi, An. subpictus, An. Minimus, and An. epiroticus. All these vectors have different ecological and seasonal distributions, transmission potential, and insecticide susceptibility status. In addition, except An. stephensi, all the five vectors comprise species complexes having sibling species which again differ in characteristics. Therefore, it is imperative to know the characteristics of the local vector population when it comes to planning control strategies. We carried out a study in tribal areas of Chhattisgarh state to investigate the seasonal and ecotype-wise distribution, breeding habits, sibling species composition, insecticide susceptibility, and role in the transmission of the local vector population. A high diversity of species was observed with around 16 species of Anopheles. An. culicifacies was the most dominant species and also was found to play a role in malaria transmission. The species was found to be resistant to dichlorodiphenyltrichloroethane (DDT) and Malathion, while an increasing trend of pyrethroid resistance was observed at some sites. Overall, our findings provide a picture of the characteristics of the local vector population in malaria-endemic regions. A study was undertaken in the villages of Korea and Bastar district (Chhattisgarh) during the years 2012–2015 to investigate the bionomics of malaria vectors and the prevalence of their sibling species complexes. Entomological surveys carried out every month included indoor resting collections, pyrethrum spray catches, light trap catches, and insecticide susceptibility status of Anopheles culicifacies using World Health Organization (WHO) methods. Anopheles culicifacies and Anopheles fluviatilis species were assayed by polymerase chain reaction (PCR) for the detection of malaria parasite, and sibling species were identified using PCR and DNA sequencing. A total of 13,186 samples of Anopheles comprising 15 species from Bastar and 16 from Korea were collected. An. Culicifacies was recorded as the most dominant species and also the only active vector at both sites. This species was found to be resistant to dichlorodiphenyltrichloroethane (DDT) and Malathion, showing signs of emerging resistance against pyrethroids. Among the sibling species of An. culicifacies, the group BCE was found in maximum numbers, while sibling species T of the An. fluviatilis was recorded to be dominant among its complex. The study provides a comprehensive view of the vector bionomics in the highly malarious regions of India that may have importance in developing vector control strategies. [ABSTRACT FROM AUTHOR]

The rice–wheat cropping system in the Indo-Gangetic Plains is the backbone of food security in India. In the 1990s, due to the scarcity of resources, the traditional Crop Establishment (CE) method shifted from Conventional Till Puddle Transplanted Rice (CTPTR) to CT Direct Seeded Rice (CTDSR) and Zero-Till DSR (ZTDSR) in paddy; and in wheat, from Conventional Till Wheat (CTW) to Zero Till Wheat (ZTW), with residue retention in rice (RRR) or in both rice and wheat (RRRW). Shift in CE methods led to change in Weed Seed Bank (WSB) dynamics and ultimately affected the weed management program. After five years of field trials, soil samples were drawn as per 2-factors factorial randomized block design. Factor-I comprised 4-CE methods, whereas factor-II consisted of 3-soil depths (0–10, 10–20 and 20–30 cm). Results showed CTPTR-CTW and ZTDSR-ZTW (RRRW) record the highest seed bank (SB) of grasses, sedges and BLWs as total weeds, in general; and predominant weeds like Echinochloa spp., Ammania baccifera, Commelina benghalensis and Digitaria sanguinalis, in particular. It also showed the higher species richness (DMg) and Shannon–Weaver (H') indices. CTDSR-CTW and CTDSR-ZTW (RRR) show the lowest WSB and at par with Shannon–Weaver (H') index; further, lowest species richness (DMg) under CTDSR-CTW. Species Evenness (J') and Simpson index (λ) vary non-significantly with CE methods. Furthermore, 0–10 cm soil depth showed the highest SB of different category of total weed, predominant weeds as well as higher values of DMg, H', and λ; whereas reverse trend was observed in Whittaker Statistic (βW). Interaction between CE methods and soil depth revealed most of WSB lying on the top layer in case of ZTDSR-ZTW (RRRW) and CTDSR-ZTW (RRR); while CTPTR-CTW showed almost uniform WSB distribution, and in case of CTDSR-CTW, a gradual decrease in WSB with soil depth. [ABSTRACT FROM AUTHOR]

The Human Immunodeficiency Virus / Acquired Immunodeficiency syndrome (HIV/AIDS) is spreading rapidly in all regions of the world. But in India it is only 20 years old. Within this short period it has emerged as one of the most serious public health problems in the country, which greatly affect the socio-economical growth. The HIV problem is very complex and ill defined from the modeling point of view. Keeping in the view the complexities of the HIV infection and its transmission, it is difficult to make exact estimates of HIV prevalence. It is more so in the Indian context, with its typical and varied cultural characteristics, and its traditions and values with special reference to sex related risk behaviors. Therefore, it is necessary to develop a good model which will help in making exact estimates of HIV prevalence that may be used for planning HIV / AIDS prevention and control programs. In this paper Neuro-Fuzzy approach has been used to develop dynamic model of HIV population of Agra region.