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Phthorimaea absoluta, an important pest of tomato crops, has reportedly developed high levels of resistance to the insecticide chlorantraniliprole, which has a unique mode of action and high efficacy. This study evaluated the sustained multigenerational effects of chlorantraniliprole on P. absoluta, focusing on resistance development, growth, development, reproductive capacity, population parameters, and nutritional indicators. After continuous selection with sublethal chlorantraniliprole for eight generations (CX-Sub8), bioassays showed that CX-Sub8 had 225.37-fold higher resistance than the susceptible strain. The age-stage, two-sex life table analysis revealed that the preadult development time and mean generation time were significantly prolonged, while population reproduction and pupal weight were reduced. Moreover, the relative fitness of CX-Sub8 was 0.62, and changes in the life table parameters correlated with an increase in the serial number of selection cycles. The second-instar larvae of CX-Sub8 presented lower triglyceride, glycerol, trehalose, free fatty acid, and protein contents than the unselected strain (CX-S8). Transcriptome analysis identified 2517 differentially expressed genes, with most being enriched in nutrient metabolism-related pathways, such as amino acid biosynthesis and fatty acid degradation metabolism. These results indicate that multigenerational sublethal chlorantraniliprole treatment disrupts the nutritional metabolism, and inhibits the growth, development, and reproduction of P. absoluta.

Optimizing nitrogen (N) fertilizer rates maintains good red raspberry (Rubus idaeus L.) production while alleviating environmental risks. Although raspberry growers in Washington are using the caneberry nutrient management guides derived from western Oregon, these guides may not be appropriate for other production regions given the differences in climate, soil type, and crop productivity. However, limited research has been conducted to observe the impact of the N fertilizer rate on floricane red raspberry growth, yield, and fruit quality in Washington. The aim of this study is to evaluate the response of “Meeker” floricane red raspberries grown in northwest Washington, USA, to different N fertilizer rates in order to provide information for future local nutrient management guides. Treatments of urea (46% nitrogen (N)) were surface-applied to raised beds of established ‘Meeker’ raspberry plots at controls, low, medium, and high rates (0, 34, 67, and 101 kg N ha−1, respectively) in 2019 and 2020. The experiment was arranged in a randomized complete block with three replications. Fruit yield and quality, plant growth and leaf tissue nutrient concentrations, and soil characteristics were evaluated. There were no N fertilizer rate treatment effects for the yield, fruit quality, plant growth, leaf tissue nutrient concentrations, and soil characteristics, except for fruit titratable acidity and soil ammonium (NH4-N) concentrations. The lack of a plant response may be due to nutrients mineralized from soil organic matter (3.81–4.0%) and the utilization of plant nutrient reserves. Based on the results, the soil organic matter level and plant nutrient reserves should be considered when making nutrient management suggestions. Fertilizer costs as well as the potential for environmental pollution from excess fertilizers could be reduced through utilizing these two potential sources of nutrients. Furthermore, longer periods of research is warranted to understand how to adjust N fertilizer rates based on plant and soil characteristics while sustaining yields.

The strategy of relying extensively on stored nutrient reserves for reproduction (capital breeding) was thought to be common in large-bodied birds breeding in harsh environments, such as arctic-nesting geese, but this view has been challenged recently. Our objective was to model inputs to the eggs from stored reserves and from local food plants in Greater Snow Geese (Chen caerulescens atlantica) breeding in the high Arctic, using a new approach based on stable-isotope signatures. Snow Geese and their eggs were collected during laying from 1999 to 2001 (N = 66 females and 110 eggs). We analyzed the isotopic signature (δ13C and δ15N) of egg constituents (lipid-free yolk, yolk lipid, and albumen), goose tissues (lipid-free breast muscles, abdominal fat, and whole liver) and of the food plants eaten by laying geese in the Arctic (graminoids and forbs). We applied a two-isotope mixing model approach to delineate nutrient input to eggs quantitatively. Differences in the isotopic signature of endogenous reserves and arctic food plants were relatively large ($5.3-8.0\\textperthousand$for Δδ13C and$7.5\\textperthousand$for Δδ15N) because reserves were accumulated in southern staging areas where geese feed in farmlands and estuarine habitats. The percentage of egg nutrients derived from exogenous sources (food consumed in the Arctic) was higher than from endogenous (body) reserves and varied little among the three years. Isotopic signatures indicated that endogenous reserves contributed 33% of lipid-free yolk nutrients, 27% of albumen, and 20% of yolk lipid, on average. Isotopic signatures of egg constituents of individual females were more strongly related to those of liver than endogenous sources (breast muscles or abdominal fat), indicating that the endogenous isotopic signature was diluted by a dietary input in the liver. We also found evidence of seasonal variation in the use of endogenous reserves. Late-laying females apparently invested proportionally more endogenous reserves in their eggs than did early layers, but not those laying larger clutches. We conclude that Greater Snow Geese use a mixed capital/income breeding strategy. Our study shows that isotopic composition of tissues can be used to infer the contribution of exogenous vs. endogenous sources of nutrients for egg formation where inputs differ isotopically.

Limited nutrient availability is one of the major challenges in organic farming. Little is known about nutrient budgets of organic farms, the underlying factors or effects on soil fertility. We therefore assessed farm gate nutrient budgets for nitrogen (N), phosphorus (P), potassium (K), magnesium (Mg) and sulfur (S) of 20 organic farms in Germany and analyzed their soil nutri-ent status. In average, the budgets showed a surplus of N (19 kg ha−1), K (5 kg ha−1), S (12 kg ha−1), and Mg (7 kg ha−1), and a deficit of P (−3 kg ha−1). There was, however, high variability between farms (e.g. standard deviation up to ± 36 kg N ha−1), which was mainly explained by different degrees of reliance on biological N fixation (BNF) as N source. When farms obtained more than 60% of their N input through BNF, they had deficits of P (mean −8 kg P ha−1) and K (mean −18 kg K ha−1). Nutrient status of most soils was within the ad-vised corridor, but for P, K and Mg, 10–15% of fields were lower and 45–63% were higher than advised. Extractable soil nutrient contents did not correlate with the nutrient budgets, inputs or outputs. Only extractable soil P increased with increasing P inputs and outputs. Fur-thermore, a decrease in extractable soil P was detected with a prolonged history of organic farming, indicating a risk of soil P mining in organic farming systems. In conclusion, the study revealed nutrient imbalances in organic farming and pointed to P and K scarcity as a major challenge for organic farms with high reliance on BNF in the long term.

Autophagy is a mechanism that enables cells to maintain cellular homeostasis by removing damaged materials and mobilizing energy reserves in conditions of starvation. Although nutrient availability strongly impacts the process of autophagy, the specific metabolites that regulate autophagic responses have not yet been determined. Recent results indicate that S‐adenosylmethionine (SAM) represents a critical inhibitor of methionine starvation–induced autophagy. SAM is primarily involved in four key metabolic pathways: transmethylation, transsulphuration, polyamine synthesis and 5′‐deoxyadenosyl 5′‐radical–mediated biochemical transformations. SAM is the sole methyl group donor involved in the methylation of DNA, RNA and histones, modulating the autophagic process by mediating epigenetic effects. Moreover, the metabolites of SAM, such as homocysteine, glutathione, decarboxylated SAM and spermidine, also exert important influences on the regulation of autophagy. From our perspective, nuclear‐cytosolic SAM is a conserved metabolic inhibitor that connects cellular metabolic status and the regulation of autophagy. In the future, SAM might be a new target of autophagy regulators and be widely used in the treatment of various diseases. Working model for SAM‐mediated modulation of autophagy. SAM is an essential metabolite that acts as a high‐energy methyl donor for most methylation modifications of non‐histone, histone, DNA and RNA, which epigenetically affect autophagic flux. Moreover, SAM is the biosynthetic precursor for HCY and cysteine and other sulphur‐containing metabolites such as GSH. All of these roles significantly contribute to the modulation of autophagy. In addition, the SAM metabolite SPD has also been shown to be a physiological inducer of autophagy. Collectively, the metabolites of SAM and the key enzymes in SAM biosynthesis and metabolism influence the core autophagy machinery. S‐adenosylmethionine: SAM, homocysteine: HCY, glutathione: GSH, spermidine: SPD, AMP‐dependent protein kinase: AMPK, mechanistic target of rapamycin: mTOR, migration inhibitory factor: MIF, cystic fibrosis transmembrane conductance regulator: CFTR, mTOR complex 1: mTORC1, protein phosphatase 2A: PP2A, nitrogen permease regulating protein: NPR2P, ten‐eleven translocation methylcytosine dioxygenases: TET, N6‐methyladenosine RNA methylation, m6A RNA methylation

[...] as political and social tensions build over the reserves of phosphate rock, the world could move from an oil-based to a phosphate-based economy, say some scientists and industry representatives. Michel Prud'homme, executive secretary of the association's Production and International Trade Committee, says that the industry anticipates that demand for fertilizers will grow at a \"fairly moderate rate\", slowing by the middle of the century. In a back-of-theenvelope calculation, he estimates that if all domestic wastewater facilities in Canada were converted into biological treatment systems using his technology, the country could produce enough fertilizer to meet about 30% of its current needs.

Root:shoot (R:S) biomass partitioning is one of the keys to the plants' ability to compensate for limiting resources in the environment and thus to survive and succeed in competition. In adult plants, it can vary in response to many factors, such as nutrient availability in the soil or reserves in the roots from the previous season. The question remains whether, at the interspecific level, reserves in seeds can affect seedlings' R:S ratio in a similar way. Proper allocation to resource‐acquiring organs is enormously important for seedlings and is likely to determine their survival and further success. Therefore, we investigated the effect of seed mass on seedling R:S biomass partitioning and its interaction with nutrient supply in the substrate. We measured seedling biomass partitioning under two different nutrient treatments after 2, 4, 6, and 12 weeks for seventeen species differing in seed mass and covering. We used phylogenetically informed analysis to determine the independent influence of seed mass on seedling biomass partitioning. We found consistently lower R:S ratios in seedlings with higher seed mass. Expectedly, R:S was also lower with higher substrate nutrient supply, but substrate nutrient supply had a bigger effect on R:S ratio for species with higher seed mass. These findings point to the importance of seed reserves for the usage of soil resources. Generally, R:S ratio decreased over time and, similarly to the effect of substrate nutrients, R:S ratio decreased faster for large‐seeded species. We show that the seed mass determines the allocation patterns into new resource‐acquiring organs during seedling development. Large‐seeded species are more flexible in soil nutrient use. It is likely that faster development of shoots provides large‐seeded species with the key advantage in asymmetric above‐ground competition, and that this could constitute one of the selective factors for optimum seed mass. Proper allocation of seed reserves to resource‐acquiring organs determines seedling survival and further success. While plant species differ in the amount of seed reserves by several orders of magnitude, we know almost nothing how the seed mass affects this resource allocation and how it interacts with the ambient availability of nutrients. We showed, using a phylogenetically informed experiment with 17 species, that species with higher seed mass are much more responsive to soil nutrient availability in terms of their resource allocation, which constitutes one of the hitherto unknown selective agents for seed mass.

An analysis of 21 coral reefs in the Indian Ocean using data across 17 years that spanned a major climatic disturbance reveals factors that predispose a coral reef to recovery or regime shift from hard corals to macroalgae; these results could foreshadow the likely outcomes of tropical coral reefs to the effects of climate change, informing management and adaptation plans. Coral reef adaptation to change When coral reefs are damaged, their ecosystem can change so radically that a new stable state is reached. This process, known as regime shift, is occurring globally: previously super-diverse reefs are becoming dominated by macroalgae instead of coral, losing animal biodiversity and potentially ecosystem services as a result. Regime shift is not ubiquitous however, and perturbed reefs can also recover to their coral-dominated state. Nicholas Graham and colleagues used long-term data from 21 perturbed reefs in the Indo-Pacific region to examine the factors predisposing a reef to recovery or regime shift. By way of this natural experiment, they identify thresholds for characteristics such as structural complexity, water depth and fish density that predict reef responses to an extreme weather event. These results improve our understanding of one of the greatest threats to marine biodiversity and could enable pre-emptive action to mitigate climate change effects on tropical coral reefs. Climate-induced coral bleaching is among the greatest current threats to coral reefs, causing widespread loss of live coral cover 1 . Conditions under which reefs bounce back from bleaching events or shift from coral to algal dominance are unknown, making it difficult to predict and plan for differing reef responses under climate change 2 . Here we document and predict long-term reef responses to a major climate-induced coral bleaching event that caused unprecedented region-wide mortality of Indo-Pacific corals. Following loss of >90% live coral cover, 12 of 21 reefs recovered towards pre-disturbance live coral states, while nine reefs underwent regime shifts to fleshy macroalgae. Functional diversity of associated reef fish communities shifted substantially following bleaching, returning towards pre-disturbance structure on recovering reefs, while becoming progressively altered on regime shifting reefs. We identified threshold values for a range of factors that accurately predicted ecosystem response to the bleaching event. Recovery was favoured when reefs were structurally complex and in deeper water, when density of juvenile corals and herbivorous fishes was relatively high and when nutrient loads were low. Whether reefs were inside no-take marine reserves had no bearing on ecosystem trajectory. Although conditions governing regime shift or recovery dynamics were diverse, pre-disturbance quantification of simple factors such as structural complexity and water depth accurately predicted ecosystem trajectories. These findings foreshadow the likely divergent but predictable outcomes for reef ecosystems in response to climate change, thus guiding improved management and adaptation.

Questions Has plant species richness in semi‐natural grasslands changed over recent decades? Do the temporal trends of habitat specialists differ from those of habitat generalists? Has there been a homogenization of the grassland vegetation? Location Different regions in Germany and the UK. Methods We conducted a formal meta‐analysis of re‐survey vegetation studies of semi‐natural grasslands. In total, 23 data sets were compiled, spanning up to 75 years between the surveys, including 13 data sets from wet grasslands, six from dry grasslands and four from other grassland types. Edaphic conditions were assessed using mean Ellenberg indicator values for soil moisture, nitrogen and pH. Changes in species richness and environmental variables were evaluated using response ratios. Results In most wet grasslands, total species richness declined over time, while habitat specialists almost completely vanished. The number of species losses increased with increasing time between the surveys and were associated with a strong decrease in soil moisture and higher soil nutrient contents. Wet grasslands in nature reserves showed no such changes or even opposite trends. In dry grasslands and other grassland types, total species richness did not consistently change, but the number or proportions of habitat specialists declined. There were also considerable changes in species composition, especially in wet grasslands that often have been converted into intensively managed, highly productive meadows or pastures. We did not find a general homogenization of the vegetation in any of the grassland types. Conclusions The results document the widespread deterioration of semi‐natural grasslands, especially of those types that can easily be transformed to high production grasslands. The main causes for the loss of grassland specialists are changed management in combination with increased fertilization and nitrogen deposition. Dry grasslands are most resistant to change, but also show a long‐term trend towards an increase in more mesotrophic species. Semi‐natural grasslands are famous for their high plant species diversity. In a meta‐analysis of 23 data sets from Germany and the UK we show that the total species richness in wet grasslands has declined over time, while in dry grasslands the number of species did not consistently change. However, there was a general decrease in the proportion of habitat specialists.

Polyhalite (POLY4), a naturally occurring multi-nutrient source with a low salt index, has potential as a replacement for muriate of potash (MOP). A field experiment was conducted to assess the effect of POLY4 on the growth, yield, quality, and nutrient use efficiency of onion and garlic, comparing nine fertilizer treatments. The results indicated that applying 100% POLY4 alone significantly enhanced the yield and nutrient uptake of both crops compared to plots treated with 100% K and S from MOP and bentonite S. Notably, potassium uptake in the POLY4 treatment exceeded the amount of potassium applied through fertilization, indicating that the crops may have mobilized additional potassium from soil reserves, which could raise concerns regarding the long-term sustainability of soil nutrient levels. However, the combination of 100% POLY4 with additional K resulted in a 6.3% yield increase in 2022–2023 and a 4.0% increase in 2023–2024 compared to the MOP treatment. This combined treatment produced statistically similar results to the MOP treatment for garlic in both years. Additionally, it significantly enhanced pyruvic acid and total protein concentrations in both crops and resulted in higher total dry matter yield and N, P, K, and S uptake. Moreover, agronomic efficiency, partial factor productivity, and recovery efficiency were notably higher in plots receiving 100% POLY4 with K. Due to its lower cost and reduced chloride content, 100% recommended S through POLY4, supplemented with K from MOP, could be recommended for sustainable onion and garlic production and improved soil health.