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For herbivorous insects with a broad diet breadth, host plant identity can influence larval development by either accelerating or delaying growth. For some species of Lepidoptera, the number of larval instars varies depending on the host plant's identity. Fall webworm (Hyphantria cunea, Drury) is a polyphagous herbivore that feeds on over 450 host plants worldwide. Of the 2 morphotypes (red- and black-head) of fall webworm, the number of instars for the red-head fall webworms has not been characterized. Given its broad diet breadth, fall webworm developmental stages may vary with plant identity. We investigated whether host plant identity affected the number of instars observed during red-head fall webworm development. We measured the head capsules of over 6,000 fall webworm larvae reared on 6 different plants commonly eaten by fall webworms in Colorado. We modeled head capsule widths as Gaussian mixture models, with a Gaussian distribution that corresponded to each instar. We show that our red-head fall webworms varied in number of instars depending on the identity of their host plant upon which they fed. We found that red-head fall webworm exhibited 7 instars on 5 of the host plants and 8 instars on 1 host plant that we studied. Our results for the number of instars for red-head fall webworm are consistent with reports of the number of instars for black-head fall webworm. Our research provides insight into the influence of host plant identity on fall webworm development, which can be used to advance lab and field research of this species., (© The Author(s) 2024. Published by Oxford University Press on behalf of Entomological Society of America. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.)

Tropical Calcific Pancreatitis (TCP) is a chronic non-alcoholic pancreatitis characterised by extensive calcification. The disease usually appears at a younger age and is more common in tropical regions. This disease's progression can lead to pancreatic diabetes, which can subsequently lead to pancreatic cancer. The CASR gene encodes a calcium-sensing receptor (CaSR), which is a GPCR protein of class C. It is expressed in the islets of Langerhans, the parathyroid gland, and other tissues. It primarily detects small gradients in circulating calcium concentrations and couples this information to intracellular signalling, which helps to regulate PTH (parathyroid hormone) secretion and mineral ion homeostasis. From co-leading insulin release, CaSR modulates ductal HCO 3- secretion, Ca 2+ concentration, cell-cell communication, β-cell proliferation, and intracellular Ca 2+ release. In pancreatic cancer, the CaSR limits cell proliferation. TCP-related four novel missense mutations P163R, I427S, D433H and V477A, found in CaSR extracellular domain (ECD) protein, which were reported in the mutTCPdb Database (https://lms.snu.edu.in/mutTCPDB/index.php). P163R mutation occurs in ligand-binding domain 1 (LBD-1) of the CaSR ECD. To investigate the influence of these variations on protein function and structural activity multiple in-silico prediction techniques such as SIFT, PolyPhen, CADD scores, and other methods have been utilized. A 500 ns molecular dynamic simulation was performed on the CaSR ECD crystal structure and the corresponding mutated models. Furthermore, Principal Component Analysis (PCA) and Essential Dynamics analysis were used to forecast collective motions, thermodynamic stabilities, and the critical subspace crucial to CaSR functions. The results of molecular dynamic simulations showed that the mutations P163R, I427S, D433H, and V477A caused conformational changes and decreased the stability of protein structures. This study also demonstrates the significance of TCP associated mutations. As a result of our findings, we hypothesised that the investigated mutations may have an effect on the protein's structure and ability to interact with other molecules, which may be related to the protein's functional impairment., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2022 Shrivastava, Mathur, Verma, Jayadev Magani, Vyas and Singh.)

The diverse ecology of parasitoids is shaped by extrinsic competition, i.e., exploitative or interference competition among adult females and males for hosts and mates. Adult females use an array of morphological, chemical, and behavioral mechanisms to engage in competition that may be either intra- or interspecific. Weaker competitors are often excluded or, if they persist, use alternate host habitats, host developmental stages, or host species. Competition among adult males for mates is almost exclusively intraspecific and involves visual displays, chemical signals, and even physical combat. Extrinsic competition influences community structure through its role in competitive displacement and apparent competition. Finally, anthropogenic changes such as habitat loss and fragmentation, invasive species, pollutants, and climate change result in phenological mismatches and range expansions within host-parasitoid communities with consequent changes to the strength of competitive interactions. Such changes have important ramifications not only for the success of managed agroecosystems, but also for natural ecosystem functioning.

Anthropogenic disturbances associated with urban ecosystems can create favorable conditions for populations of some invasive plant species. Light pollution is one of these disturbances, but how it affects the growth and establishment of invasive plant populations is unknown. Cheatgrass ( Bromus tectorum ) is a problematic invasive species where it has displaced native grassland communities in the United States, but to our knowledge, there have been no studies of the ecological factors that affect cheatgrass presence in urban ecosystems. We conducted field surveys in urban alleys in Denver, Colorado, to compare the presence of cheatgrass at sites with and without artificial light at night (hereafter artificial light) from streetlights. These streetlights are mounted on utility poles, which cause ground disturbance when installed in alleys; we were able to test the independent effect of poles on cheatgrass establishment because not all poles have streetlights on them. We found that cheatgrass was positively associated with the presence of streetlights and to a lesser extent poles. In addition to cheatgrass, we also found that other plants were positively associated with the presence of both poles and streetlights. Our results suggest that artificial light may benefit the occurrence of cheatgrass and other plant species in urban settings. While invasive populations of cheatgrass in wild habitats attract the most attention from managers, we suggest more consideration for this grass in urban environments where its growth and establishment benefit from anthropogenic changes., Competing Interests: None declared., (© 2021 The Authors. Ecology and Evolution published by John Wiley & Sons Ltd.)

Interspecific competition for limited resources can drive ecological specialization and trait expression. Organisms released from intense competition may exploit a broader range of resources, but if reunited with stronger competitors, survivorship may depend on foraging behaviors that reduce competition. We compared the host selection behavior of the parasitoid Cotesia glomerata from two North American populations that differ in their association with Cotesia rubecula, a superior competitor. Both parasitoids originate from Europe and attack the imported cabbageworm (a.k.a. small cabbage white) Pieris rapae, but C. glomerata was introduced into North America almost a century before C. rubecula. After re-association in North America, C. rubecula has displaced C. glomerata in several regions, but not in other regions. Host selection was measured in female C. glomerata from Maryland (MD) where it coexists with C. rubecula, and in conspecifics from Colorado (CO) where C. rubecula is absent. Unparasitized and C. rubecula-parasitized P. rapae hosts were used in choice tests to examine whether C. glomerata host selection behavior differed based on the population's association history with C. rubecula. We found that C. glomerata from MD had a higher likelihood of avoiding hosts parasitized by C. rubecula (and thus avoiding competition) than did wasps from CO. The ability of C. glomerata to avoid hosts parasitized by C. rubecula may facilitate coexistence in MD; whereas, the lack of discrimination in CO populations of C. glomerata naïve to C. rubecula could contribute to the displacement of C. glomerata were C. rubecula to enter the same habitat.

Haloxylon salicornicum is an economically important perennial woody shrub of family Amaranthaceae and is a good source of food additives, fodder, fuel and nutrients in Indian Thar Desert. In vitro regeneration of H. salicornicum through nodal shoot segments is achieved in present investigation. Young green shoots in horizontal orientation were found to be more responsive than vertical orientation. Axillary shoot buds were activated on MS medium containing 10 µM BAP. Adventitious roots with intense root hairs were induced on horizontally placed shoots on half strength MS medium containing 2 µM NOA + 100 mg L -1 activated charcoal. This is a first report on micropropagation of H. salicornicum. This protocol can be a useful means for in vitro characterization, mass propagation and conservation of the plant for future prospects.