Which SDM Model, CLIMEX vs. MaxEnt, Best Forecasts Aeolesthes sarta Distribution at a Global Scale under Climate Change Scenarios?

A precise evaluation of the risk of establishing insect pests is essential for national plant protection organizations. This accuracy is crucial in negotiating international trade agreements for forestry-related commodities, which have the potential to carry pests and lead to unintended introductions in the importing countries. In our study, we employed both mechanistic and correlative niche models to assess and map the global patterns of potential establishment for Aeolesthes sarta under current and future climates. This insect is a significant pest affecting tree species of the genus Populus, Salix, Acer, Malus, Juglans, and other hardwood trees. Notably, it is also categorized as a quarantine pest in countries where it is not currently present. The mechanistic model, CLIMEX, was calibrated using species-specific physiological tolerance thresholds, providing a detailed understanding of the environmental factors influencing the species. In contrast, the correlative model, maximum entropy (MaxEnt), utilized species occurrences and spatial climatic data, offering insights into the species' distribution based on observed data and environmental conditions. The projected potential distribution from CLIMEX and MaxEnt models aligns well with the currently known distribution of A. sarta. CLIMEX predicts a broader global distribution than MaxEnt, indicating that most central and southern hemispheres are suitable for its distribution, excluding the extreme northern hemisphere, central African countries, and the northern part of Australia. Both models accurately predict the known distribution of A. sarta in the Asian continent, and their projections suggest a slight overall increase in the global distribution range of A. sarta with future changes in climate temperature, majorly concentrating in the central and northern hemispheres. Furthermore, the models anticipate suitable conditions in Europe and North America, where A. sarta currently does not occur but where its preferred host species, Populus alba, is present. The main environmental variables associated with the distribution of A. sarta at a global level were the average annual temperature and precipitation rate. The predictive models developed in this study offer insights into the global risk of A. sarta establishment and can be valuable for monitoring potential pest introductions in different countries. Additionally, policymakers and trade negotiators can utilize these models to make science-based decisions regarding pest management and international trade agreements.

Flavonoids: a review on biosynthesis and transportation mechanism in plants.

In recent years, significant progress has been made in understanding the biosynthetic pathway and regulation of flavonoids through forward genetic approaches. However, there remains a notable gap in knowledge regarding the functional characterization and underlying processes of the transport framework responsible for flavonoid transport. This aspect requires further investigation and clarification to achieve a comprehensive understanding. Presently, there are a total of four proposed transport models associated with flavonoids, namely glutathione S-transferase (GST), multidrug and toxic compound extrusion (MATE), multidrug resistance-associated protein (MRPs), and bilitranslocase-homolog (BTL). Extensive research has been conducted on the proteins and genes related to these transport models. However, despite these efforts, numerous challenges still exist, leaving much to be explored in the future. Gaining a deeper understanding of the mechanisms underlying these transport models holds immense potential for various fields such as metabolic engineering, biotechnological approaches, plant protection, and human health. Therefore, this review aims to provide a comprehensive overview of recent advancements in the understanding of flavonoid transport mechanisms. By doing so, we aim to paint a clear and coherent picture of the dynamic trafficking of flavonoids.

Pharmacological Modulation of Smooth Muscles and Platelet Aggregation by Psidium cattleyanum.

Traditionally, in the Southern Asian countries, Psidium cattleyanum is a widely used plant for the management of various ailments such as gastrointestinal, respiratory, and cardiac disorders, but it lacks proof on a scientific basis, and therefore, this is the major emphasis of the current research work. Crude extract of Psidium cattleyanum (Pc.Cr) was preliminary analyzed for the presence of different classes of bioactive molecules. The aqueous and dichloromethane fractions of Pc.Cr were subjected to in vitro and in vivo studies. It was applied at variable concentrations (0.1-10 mg/ml) to isolated rabbit jejunum to investigate spasmolytic effect. Concentration dependent curves of calcium were constructed to check the calcium channel antagonistic activity. For the evaluation of tracheorelaxant activity, isolated tracheal tissue was treated with High-K+ (80 mM) and carbachol (CCh) and then challenged cumulatively with Pc.Cr. To study the antidiarrheal effect of the plant extract, castor oil-induced diarrhea model was adopted. For evaluation of the hypotensive effect of Pc.Cr, it was given intravenously to preanesthetized normotensive rats, and the response was recorded using pressure transducer. Platelet rich plasma was used for the assessment of the antiplatelet activity when challenged with purinergic and adrenergic agonists. Concentration-dependent inhibition of spontaneous and High-K+ mediated contractions in isolated jejunum was observed by the application of Pc.Cr. Contractions induced in isolated tracheal tissue by High-K+ and CCh were inhibited by application of Pc.Cr to these tissues. Similarly, application of Pc.Cr to High-K+ and phenylephrine (PE) treated aortic strips resulted in vasodilation. Platelet aggregation inhibition was shown by Pc.Cr against adenosine diphosphate (ADP) only. The antidiarrheal effect was observed as a reduction in the total number of feces in Pc.Cr-treated mice when given castor oil. Dose-dependent hypotension was seen in normotensive rats when treated with Pc.Cr intravenously. This study showed the spasmolytic, tracheorelaxant, vasodilator, platelet aggregation inhibitory, antidiarrheal, and hypotensive activities of P. cattleyanum which may be due to the blockage of calcium channels, but the involvement of any other pathway cannot be ignored.

Pharmacological investigation of activities pertaining to modulation of gastrointestinal, respiratory and cardiovascular parameters by Indigofera argentea in experimental models.

Indigofera argentea is widely used for the management of gastrointestinal, respiratory and cardiac disorders. This study was done to explore scientific basis of its uses. Aqueous methanolic extract of Indigofera argentea and its fractions were studied on isolated tissues of rabbit's jejunum, trachea, aorta and atrium. Castor oil induced diarrheal model was used for the study of the antidiarrheal effect and pre-anesthetized rats were used for hypotensive study. Concentration dependent spasmolytic effect of the extract upon isolated jejunum, trachea and aorta was observed. Concentration response curves constructed upon isolated rabbit jejunum, revealed the presence of calcium channel blocker in the plant extract. Moreover, significant reduction (P<0.05) in atrial force of contraction but non-significant reduction in rate of contraction was seen by the application of plant extract. Protection (P<0.05) against diarrhea was observed by the administration of crude extract to rats which were pretreated with castor oil. When given to rats intravenously, the extract showed hypotensive effect. Experimental findings justified the traditional uses of Indigofera argentea on pharmacological basis for the management of disorders pertaining to gut, airway and hypertensive situation.

Phytolith Formation in Plants: From Soil to Cell.

Silica is deposited extra- and intracellularly in plants in solid form, as phytoliths. Phytoliths have emerged as accepted taxonomic tools and proxies for reconstructing ancient flora, agricultural economies, environment, and climate. The discovery of silicon transporter genes has aided in the understanding of the mechanism of silicon transport and deposition within the plant body and reconstructing plant phylogeny that is based on the ability of plants to accumulate silica. However, a precise understanding of the process of silica deposition and the formation of phytoliths is still an enigma and the information regarding the proteins that are involved in plant biosilicification is still scarce. With the observation of various shapes and morphologies of phytoliths, it is essential to understand which factors control this mechanism. During the last two decades, significant research has been done in this regard and silicon research has expanded as an Earth-life science superdiscipline. We review and integrate the recent knowledge and concepts on the uptake and transport of silica and its deposition as phytoliths in plants. We also discuss how different factors define the shape, size, and chemistry of the phytoliths and how biosilicification evolved in plants. The role of channel-type and efflux silicon transporters, proline-rich proteins, and siliplant1 protein in transport and deposition of silica is presented. The role of phytoliths against biotic and abiotic stress, as mechanical barriers, and their use as taxonomic tools and proxies, is highlighted.

A CAM- and starch-deficient mutant of the facultative CAM species Mesembryanthemum crystallinum reconciles sink demands by repartitioning carbon during acclimation to salinity.

In the halophytic species Mesembryanthemum crystallinum, the induction of crassulacean acid metabolism (CAM) by salinity requires a substantial investment of resources in storage carbohydrates to provide substrate for nocturnal CO(2) uptake. Acclimation to salinity also requires the synthesis and accumulation of cyclitols as compatible solutes, maintenance of root respiration, and nitrate assimilation. This study assessed the hierarchy and coordination of sinks for carbohydrate in leaves and roots during acclimation to salinity in M. crystallinum. By comparing wild type and a CAM-/starch-deficient mutant of this species, it was sought to determine if other metabolic sinks could compensate for a curtailment in CAM and enable acclimation to salinity. Under salinity, CAM deficiency reduced 24 h photosynthetic carbon gain by >50%. Cyclitols were accumulated to comparable levels in leaves and roots of both the wild type and mutant, but represented only 5% of 24 h carbon balance. Dark respiration of leaves and roots was a stronger sink for carbohydrate in the mutant compared with the wild type and implied higher maintenance costs for the metabolic processes underpinning acclimation to salinity when CAM was curtailed. CAM required the nocturnal mobilization of >70% of primary carbohydrate in the wild type and >85% of carbohydrate in the mutant. The substantial allocation of carbohydrate to CAM limited the export of sugars to roots, and the root:shoot ratio declined under salinity. The data suggest a key role for the vacuole in regulating the supply and demand for carbohydrate over the day/night cycle in the starch-/CAM-deficient mutant.