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Goat willow (Salix caprea L.) is an ecologically important, cold-tolerant pioneer species that spreads from central Anatolia to Black Sea regions in Türkiye. Completed and ongoing construction of hydroelectric plants, especially in northeastern Türkiye, threaten the genetic resources of goat willow in the region due to habitat loss and fragmentation. Therefore, it is important to assess genetic diversity structure and magnitude of goat willow populations in the northeastern Black Sea Region for effective conservation and utilization of genetic resources of the species. To characterize the genetic diversity of goat willow, 180 trees were sampled from 5 river systems and screened by using ten microsatellite markers for genotyping, consequently analysis were carried out to estimate population genetic diversity parameters of populations. The results revealed that both observed (Ho = 0.50) and expected (He = 0.53) genetic diversities were low, but observed genetic diversity was less than expected due fragmentation and reduction in population sizes. Genetic structure analysis of populations suggested the presence of three major groups. This structuring appeared to be caused by the restricted gene flow (pollen, seed or vegetative material) through insects, wind and water due to geographical barrier (the east Black Sea mountain ranges) acting as geographic isolation mechanism between the populations of the Çoruh river and the river systems located in the west of Çoruh river. To prevent further deterioration of genetic diversity due to habitat loss and fragmentation in the studied river systems in the region, we suggest that one population with high genetic diversity, unique alleles and low inbreeding from each genetic structure cluster should be designated as in situ conservation sites. The genetic resources from such in situ designated populations will facilitate future efficient restoration, genetic resource management and utilization works with the species. [ABSTRACT FROM AUTHOR]

Differences in migratory behavior have been suggested to drive speciation, but the genetics underlying this process remain unknown. Identification and study of migratory divides can help us understand how differential migration can lead to reproductive isolation. Here, we genotyped Willow Warblers Phylloscopus trochilus, from the Åland islands, located in between the ranges of the differentially migrating subspecies P. t. trochilus and P. t. acredula. We found that Willow Warblers on the Åland islands were genetically intermediate to allopatric populations of both parental subspecies, providing evidence that the islands constitute a previously unknown hybrid swarm, likely to be a migratory divide. [ABSTRACT FROM AUTHOR]

Biased sex ratios among reproductive individuals are common in plants, but the underlying mechanisms, as well as the evolutionary consequences, are not well understood. The classical theory of Düsing and Fisher predicts an equal primary sex ratio at seed production, based on the selective advantage of the rare sex. Biased sex ratios among reproductive plants can arise from sexual dimorphism in survival and flowering. Sex ratio biases can also be present from the seed stage; in these cases, assumptions of Düsing's and Fisher's theory, for example, random mating or demographic equilibrium, are thought to be violated. We investigated mechanisms leading to female‐biased sex ratios in the arctic‐alpine dwarf willow Salix herbacea L. We studied sex ratios in three natural populations over 3 years as well as in 29 crosses (full‐sib families) under controlled conditions over four growth periods. We tested whether sex ratio was associated with habitat parameters (elevation and snowmelt time), or with germination, survival or flowering, and whether females and males differed in size or flowering that may cause observation bias. We detected a strong and consistent female bias, both in natural populations (sex ratio [proportion of females]: 0.71–0.82) and in our controlled experiment (overall sex ratio: 0.70–0‐72). Female bias became more pronounced with increasing elevation. Our data did not support sexual dimorphism in size or flowering. Family sex ratios varied largely (from 0.25 to 1), including many female‐biased families, unbiased families and two male‐biased families. Families with lower germination, seedling establishment, survival or flowering did not have stronger female bias, indicating that intrinsically higher survival or flowering in females does not explain overall female bias. Synthesis. Our results suggest that sex ratio bias in S. herbacea is already present in seeds and does not arise through intrinsic differences between sexes. Candidate mechanisms that can lead to both overall female bias and variation in sex ratio among families are meiotic drive or cyto‐nuclear interactions. The pioneer habit of Salix may lead to non‐equilibrium population dynamics that allow for the long‐term persistence of variable genetic sex ratio distortion systems that arise from genetic conflict. [ABSTRACT FROM AUTHOR]

Background: The pollution of soil by heavy metals, particularly Cd, is constitutes a critical international environmental concern. Willow species are renowned for their efficacy in the phytoremediation of heavy metals owing to their high Cd absorption rate and rapid growth. However, the mechanisms underlying microbial regulation for high- and low-accumulating willow species remain poorly understood. Therefore, we investigated the responses of soil and rhizosphere microbial communities to high- and low-Cd-accumulating willows and Cd contamination. We analyzed soil properties were analyzed in bulk soil (SM) and rhizosphere soil (RM) planted with high-accumulating (H) and low-accumulating (L) willow species. Results: Rhizosphere soil for different willow species had more NH4+ than that of bulk soil, and RM-H soil had more than RM-L had. The available phosphorus content was greater in hyper-accumulated species than it was in lower-accumulated species, especially in RM-H. Genome sequencing of bacterial and fungal communities showed that RM-L exhibited the highest bacterial diversity, whereas RM-H displayed the greatest richness than the other groups. SM-L exhibited the highest diversity and richness of fungal communities. Ralstonia emerged as the predominant bacterium in RM-H, whereas Basidiomycota and Cercozoa were the most enriched fungi in SM-H. Annotation of the N and C metabolism pathways revealed differential patterns: expression levels of NRT2, NarB, nirA, nirD, nrfA, and nosZ were highest in RM-H, demonstrating the effects of NO3-and N on the high accumulation of Cd in RM-H. The annotated genes associated with C metabolism indicated a preference for the tricarboxylic pathway in RM-H, whereas the hydroxypropionate-hydroxybutyrate cycle was implicated in C sequestration in SM-L. Conclusions: These contribute to elucidation of the mechanism underlying high Cd accumulation in willows, particularly in respect of the roles of microbes and N and C utilization. This will provide valuable insights for repairing polluted soil using N and employing organic acids to improve heavy metal remediation efficiency. [ABSTRACT FROM AUTHOR]

Modification of food webs is a frequent cause of shifts in ecosystem states that resist reversal when the food web is restored to its original condition. We used the restoration of the large carnivore guild including gray wolves (Canis lupis), cougars (Felis concolor), and grizzly bears (Ursus arctos horribilis) to the northern range of Yellowstone National Park as a model system to understand how ecosystems might resist reconfiguration after the restoration of apex predators to the food web. The absence of wolves, cougars, and grizzly bears for nearly a century from the northern range was the primary cause of dramatic changes in riparian plant communities. Willows (Salix spp.) were suppressed in height by intense browsing by the dominant herbivore, elk (Cervus canadensis). The loss of activity by beavers (Castor canadensis) coincided with the loss of tall willows. We hypothesized that intense elk browsing interrupted the mutualism between willow and beavers: ecosystem engineering by beavers was a critical component of willow habitat and tall willows were a critical component of habitat for beavers. This interruption made riparian communities resilient to the disturbance caused by the restoration of apex predators. We hypothesized further that reductions in elk browsing attributable to reductions in elk population size were not sufficient to prevent the suppression of willow growth. To test these hypotheses, we conducted a 20‐year, factorial experiment that crossed simulated beaver dams with the exclusion of browsing. We found that willows grew to heights expected for restored communities only in the presence of dams and reduced browsing. Willows experiencing ambient conditions remained well below this expectation. We found no difference in heights or growth rates of willows in experimental controls and willows in 21 randomly chosen sites, confirming that the results of the experiment were representative of range‐wide conditions. A reorganized community of large herbivores was implicated in the suppression of willow growth. We conclude that the restoration of large carnivores to the food web failed to restore riparian plant communities on Yellowstone's northern range, supporting the hypothesis that this ecosystem is in an alternative stable state caused primarily by the extirpation of apex predators during the early 20th century. [ABSTRACT FROM AUTHOR]

Renewable energy resources such as biomass are crucial for a sustainable global society. Trees are a major source of lignocellulosic biomass, which can vary in response to different environmental factors owing to epigenetic regulation, such as DNA C‐methylation. To investigate the effects of DNA methylation on plant development and wood formation, and its impacts on gene expression, with a focus on secondary cell wall (SCW)‐associated genes, Salix purpurea plantlets were cloned from buds derived from a single hybrid tree for both treatment and control conditions. For the treatment condition, buds were exposed to 50 μM zebularine in vitro and a combined strategy of whole‐genome bisulfite sequencing (WGBS) and RNA‐seq was employed to examine the methylome and transcriptome profiles of different tissues collected at various time points under both conditions. Transcriptomic and methylome data revealed that most of the promoter and gene body demethylation had no marked effects on the expression profiles of genes. Nevertheless, gene expression tended to decrease with the increased methylation levels of genes with highly methylated promoters. Results indicated that demethylation is less evident in centromeric regions and sex chromosomes. Promoters of secondary cell wall‐associated genes, such as 4‐coumarate‐CoA ligase‐like and Rac‐like GTP‐binding protein RHO, were differentially methylated in the secondary xylem samples collected from two‐month potted treated plants compared to control samples. Our results provide novel insights into DNA methylation and gene expression landscapes and a basis for investigating the epigenetic regulation of wood formation in S. purpurea as a model plant for bioenergy species. [ABSTRACT FROM AUTHOR]

The production of bioproduct feedstocks such as switchgrass (Panicum virgatum L.) and willow (Salix spp.) on degraded lands provides an opportunity to grow dedicated bioenergy crops with the potential to capture and store carbon in the soil while reducing competition with land for food production. However, how the production of these crops alters plant–soil–microbe interactions that govern soil C accumulation in highly degraded soil is underexplored. The objectives of this study were to examine select biological and chemical properties related to stable soil organic matter (SOM) production from the growth of switchgrass and willow on marginal soil over two growing seasons and whether biochar amendment can positively affect these parameters. To address our objectives, paired former surface mined lands and non‐mine impacted marginal agriculture sites were selected across West Virginia, USA, and biochar and unamended control treatments were imposed. Through the first two growing seasons, microbial activity and demand for carbon (C) increased and was accompanied by a shift in extracellular enzyme investment for decomposition‐associated enzymes. Mineral‐associated organic matter C increased over the two growing seasons, and this increase was greater in the mine sites compared to the agriculture sites. Compared to each site's previous land use, C losses were observed under bioproduct systems in the agriculture, but not the mine sites. Biochar amendments did not impact microbial activity but did increase the C:N of SOM. Overall, our results suggest that the early growth of switchgrass and willow can result in C accumulation in marginal and highly degraded lands. Core Ideas: Switchgrass (Panicum virgatum L.) and willow (Salix spp.) can be produced for bioproducts on highly degraded soil.Microbial demand for carbon (C) increased, while C inputs from the crops were variable over the first two growing seasons.Short‐term C losses were observed as compared to the previous land usein the agriculture, but not the reclaimed mine sites.There is potential for carbon accumulation in Appalachian reclaimed mine and marginal agriculture soil. [ABSTRACT FROM AUTHOR]

Riparian woody plant communities, including shrubs and trees, are essential for maintaining biodiversity, protecting against floods, reducing erosion, and transporting nutrients. However, these habitats are greatly threatened by human activities, particularly agricultural land acquisition, and the introduction of invasive species. This study examined species diversity and interspecific association in riparian woody plant communities along rivers in the Romanian Carpathians. The study focused on communities of Salix purpurea, S. alba, and Hippophaë rhamnoides in mountain regions, with varying sampling efforts at different sites for each species. A total of 174 plant species were found, predominantly herbaceous (77.9%), followed by trees (11.6%) and shrubs (10.5%). While S. alba and S. purpurea communities show high species richness and abundance, S. alba has slightly higher diversity (H′ ≈ 2.23, SD = 0.28) than S. purpurea (H′ ≈ 1.69, SD = 0.42). Contrarily, significant differences exist between H. rhamnoides and S. alba communities in species richness (p =.007) and Shannon diversity (p =.004). PCA analysis elaborated on distinct distribution patterns of plant associations within habitats S. purpurea community, H. rhamnoides community, and S. alba community. Four invasive species (Oenothera biennis L. and Oxalis stricta L. in S. alba communities, Reynoutria sachalinensis Nakai in both S. purpurea and H. rhamnoides communities, and Erigeron canadensis L. in H. rhamnoides communities) were identified, as requiring conservation efforts. Hemicryptophytes dominate species richness, while microphanerophytes and megaphanerophytes significantly contribute to plant abundance. H. rhamnoides formed Hippophaë rhamnoides dunes (2160) Natura 2000 habitat, while S. alba created galleries within the 92A0 Salix alba and Populus alba habitat. In conclusion, the findings from this study highlight the importance of preserving riparian habitats because their value goes beyond local or regional considerations and extends to the global scale due to their unique characteristics. [ABSTRACT FROM AUTHOR]

Wireless sensor networks (WSNs) play a critical role in environmental sensing and data transmission. However, their performances are often hindered by challenges like localization accuracy and storage capacity. Existing variants of DV-Hop algorithm suffer from issues like high memory usage, low localization accuracy, and limited applicability in realistic three-dimensional (3D) environments. To overcome these challenges and solve the localization problem for DV-Hop based WSN nodes in 3D space, this research proposes a novel hybrid optimizer called PCWCO (Parallel Compact Willow Catkin Optimization Algorithm). The PCWCO algorithm incorporates compact technique and a new parallel strategy into the Willow Catkin Optimization (WCO) framework, aiming to reduce memory usage while enhancing solution quality. Rigorous numerical validations are conducted using benchmark functions from the CEC2017 to assess the performance of the proposed PCWCO optimizer. The results demonstrate that PCWCO exhibits competitive performance compared to classical intelligent optimization algorithms. Moreover, we synergistically integrate the PCWCO algorithm with DV-Hop to form a hybrid approach called PCWCO-3D-DV-Hop to facilitate the localization efficiency of WSN nodes in 3D space. [ABSTRACT FROM AUTHOR]

Simple Summary: The Asian longhorned beetle (ALB), Anoplophora glabripennis Motschulsky, is a serious wood borer of hardwood trees in North America, Europe, and China, causing substantial economic and ecological losses. Several ALB management strategies have been applied; however, certain drawbacks have been identified with these strategies. To explore effective and environmentally sustainable management options, we investigated the biological characteristics of ALB, including the distribution of frass and emergence holes on trees and preferred branches for ALB foraging and ovipositing. The results showed that 76.31–78.88% of frass holes and 85.08–87.93% of emergence holes were located above a height of 200 cm. Adults showed a preference for feeding on branches 2–3 cm in diameter, and eggs were predominantly laid on 5 cm branches, primarily located above a height of 200 cm. These findings suggest a correlation between the number of ALBs and the height of the tree crown. To test this hypothesis, we investigated whether the number of ALBs decreased when the tree crown was removed above 200 cm (high trunk truncation, HTT). The results revealed a significant decrease in the number after the implementation of HTT. Based on our results we advocate for HTT as an effective ALB management strategy, offering valuable insights into the development of a sustainable approach to controlling the number of ALBs. The Asian longhorned beetle (ALB) causes substantial economic and ecological losses, thus, an environmentally friendly management strategy is needed. Here, we propose high trunk truncation (HTT), the removal of the above 200 cm portion of trees, as a sustainable management strategy to control ALB. To examine the hypothesis, an initial step involved the assessment of various biological characteristics of ALB. Subsequently, a controlled field experiment was carried out utilizing HTT. Finally, HTT was applied in two additional ALB infestation regions. The results of the study of the biological characteristics of ALB showed that 76.31–78.88% of frass holes and 85.08–87.93% of emergence holes were located on branches above 200 cm. Adults preferred to feed on branches 2–3 cm in diameter, ALB eggs were predominantly laid on 5 cm branches, and both were primarily located above 200 cm. These results revealed a correlation between the number of ALBs and the tree crown height. The controlled field experiment showed that the number of ALBs was significantly decreased when the HTT strategy was implemented: approximately 90% of frass holes and 95% of adults were eradicated by HTT compared with the control. Different field surveys involving HTT have shown similar results. These findings provide valuable insights into a sustainable and efficient management strategy for reducing the number of ALBs. [ABSTRACT FROM AUTHOR]

Solid biomass can be used for energy generation and the production of various renewable bioproducts. The aim of this study was to determine the yield and characteristics of wood obtained as debarking residue from 14 genotypes of short-rotation woody crops (SRWCs). These included five Populus genotypes, one Robinia genotype, and eight Salix genotypes, harvested in both annual and quadrennial cycles. The results showed that the highest dry wood yield (12.42 Mg ha−1 y−1 DM) and yield energy value (244.34 GJ ha−1 y−1) were obtained from willow (cultivar Żubr) harvested in a quadrennial cycle. The best effect among the poplar genotypes was achieved for the Hybryda275, and it was particularly marked in the quadrennial harvest cycle. The poorest results were determined for black locust. The Robinia characteristics included the significantly lowest moisture content (31.6%), which was a positive attribute from the energy point of view, but, on the other hand, it had some adverse characteristics—the highest levels of sulfur (0.033% DM), nitrogen (0.38% DM), and ash (0.69% DM). More beneficial properties in this respect were determined for willow and poplar wood. Moreover, willow and poplar wood contained more cellulose—51.8 and 50.0% DM, respectively—compared with black locust. Extending the SRWC shoot harvest cycle from annual to quadrennial resulted in an increase in cellulose, lignin, and carbon, higher heating value, and a decrease in nitrogen, sulfur, ash, and moisture content. Therefore, extending the harvest cycle improved the parameters of SRWC wood as an energy feedstock. [ABSTRACT FROM AUTHOR]

Background: Homeodomain-leucine zipper (HD-Zip) transcription factors are plant-specific and play important roles in plant defense against environmental stresses. Identification and functional studies have been carried out in model plants such as rice, Arabidopsis thaliana, and poplar, but comprehensive analysis on the HD-Zip family of Salix suchowensis have not been reported. Results: A total of 55 HD-Zip genes were identified in the willow genome, unevenly distributed on 18 chromosomes except for chromosome 19. And segmental duplication events containing SsHD-Zip were detected on all chromosomes except chromosomes 13 and 19. The SsHD-Zip were classified into 4 subfamilies subfamilies (I-IV) according to the evolutionary analysis, and members of each subfamily shared similar domain structure and gene structure. The combination of GO annotation and promoter analysis showed that SsHD-Zip genes responded to multiple abiotic stresses. Furthermore, the results of qPCR analysis showed that the SsHD-Zip I gene exhibited different degrees of expression under salt stress, PEG treatment and heat treatment. Moreover, there was a synergistic effect between SsHD-Zip I genes under stress conditions based on coregulatory networks analysis. Conclusions: In this study, HD-Zip transcription factors were systematically identified and analyzed at the whole genome level. These results preliminarily clarified the structural characteristics and related functions of willow HD-Zip family members, and it was found that SsHox34, SsHox36 and SsHox51 genes were significantly involved in the response to various stresses. Together, these findings laid the foundation for further research on the resistance functions of willow HD-Zip genes. [ABSTRACT FROM AUTHOR]

In nature, plants are exposed to a range of climatic conditions. Those negatively impacting plant growth and survival are called abiotic stresses. Although abiotic stresses have been extensively studied separately, little is known about their interactions. Here, we investigate the impact of long-term mild metal exposure on the cold acclimation of Salix viminalis roots using physiological, transcriptomic, and proteomic approaches. We found that, while metal exposure significantly affected plant morphology and physiology, it did not impede cold acclimation. Cold acclimation alone increased glutathione content and glutathione reductase activity. It also resulted in the increase in transcripts and proteins belonging to the heat-shock proteins and related to the energy metabolism. Exposure to metals decreased antioxidant capacity but increased catalase and superoxide dismutase activity. It also resulted in the overexpression of transcripts and proteins related to metal homeostasis, protein folding, and the antioxidant machinery. The simultaneous exposure to both stressors resulted in effects that were not the simple addition of the effects of both stressors taken separately. At the antioxidant level, the response to both stressors was like the response to metals alone. While this should have led to a reduction of frost tolerance, this was not observed. The impact of the simultaneous exposure to metals and cold acclimation on the transcriptome was unique, while at the proteomic level the cold acclimation component seemed to be dominant. Some genes and proteins displayed positive interaction patterns. These genes and proteins were related to the mitigation and reparation of oxidative damage, sugar catabolism, and the production of lignans, trehalose, and raffinose. Interestingly, none of these genes and proteins belonged to the traditional ROS homeostasis system. These results highlight the importance of the under-studied role of lignans and the ROS damage repair and removal system in plants simultaneously exposed to multiple stressors. [ABSTRACT FROM AUTHOR]

Mongolian willow (Salix linearistipularis) is a naturally occurring woody dioecious plant in the saline soils of north-eastern China, which has a high tolerance to alkaline salts. Although transcriptomics studies have identified a large number of salinity-responsive genes, the mechanism of salt tolerance in Mongolian willow is not clear. Here, we found that in response to Na2CO3 stress, Mongolian willow regulates osmotic homeostasis by accumulating proline and soluble sugars and scavenges reactive oxygen species (ROS) by antioxidant enzymes and non-enzymatic antioxidants. Our quantitative proteomics study identified 154 salt-sensitive proteins mainly involved in maintaining the stability of the photosynthetic system and ROS homeostasis to cope with Na2CO3 stress. Among them, Na2CO3-induced rubredoxin (RUB) was predicted to be associated with 122 proteins for the modulation of these processes. The chloroplast-localized S. linearistipularis rubredoxin (SlRUB) was highly expressed in leaves and was significantly induced under Na2CO3 stress. Phenotypic analysis of overexpression, mutation and complementation materials of RUB in Arabidopsis suggests that SlRUB is critical for the regulation of photosynthesis, ROS scavenging and other metabolisms in the seedlings of Mongolian willow to cope with Na2CO3 stress. This provides more clues to better understand the alkali-responsive mechanism and RUB functions in the woody Mongolian willow. [ABSTRACT FROM AUTHOR]

Shrub willows are widely planted for landscaping, soil remediation, and biomass production, due to their rapid growth rates. Identification of regulatory genes in wood formation would provide clues for genetic engineering of willows for improved growth traits on marginal lands. Here, we conducted an expression quantitative trait locus (eQTL) analysis, using a full sibling F1 population of Salix suchowensis, to explore the genetic mechanisms underlying wood formation. Based on variants identified from simplified genome sequencing and gene expression data from RNA sequencing, 16,487 eQTL blocks controlling 5505 genes were identified, including 2148 cis-eQTLs and 16,480 trans-eQTLs. eQTL hotspots were identified, based on eQTL frequency in genomic windows, revealing one hotspot controlling genes involved in wood formation regulation. Regulatory networks were further constructed, resulting in the identification of key regulatory genes, including three transcription factors (JAZ1, HAT22, MYB36) and CLV1, BAM1, CYCB2;4, CDKB2;1, associated with the proliferation and differentiation activity of cambium cells. The enrichment of genes in plant hormone pathways indicates their critical roles in the regulation of wood formation. Our analyses provide a significant groundwork for a comprehensive understanding of the regulatory network of wood formation in S. suchowensis. [ABSTRACT FROM AUTHOR]

The practice of beating willows on Hoshanah Rabbah is a very unusual one, with no explanations offered in the Talmud or Midrash. In the ancient world, the willow represented both fertility and infertility, life and death, and the beating of willows can be connected both to beating with plants as a fertility ritual and as a form of scapegoat ritual. Echoes of both of these ideas are found in Sephardic folk practices associated with beating people with willows as well as the earliest Gaonic explanation for this practice, in addition to the later explanations found in the Zohar. [ABSTRACT FROM AUTHOR]

Stigmella zelleriella (Snellen, 1875) (Lepidoptera: Nepticulidae) is reported breeding at Dungeness, East Kent in 2022. Mines were found on Salix repens L. var. argentea (Sm.) Wimm. et Grab. across the peninsula and adults reared to confirm the identification. The identification and biology of this species in the UK are considered and the significance of this find for the species' conservation is discussed. [ABSTRACT FROM AUTHOR]

Kahikatea (Dacrycarpus dacrydioides) is a tall, wetland‐tolerant native podocarp tree that has potential for restoration of New Zealand wetlands currently dominated by invasive Grey willow (Salix cinerea). We investigated methods to jump‐start establishment of Kahikatea saplings in the Ramsar‐listed Whangamarino Wetland. Treatments involved planting saplings after full herbicide clearance of the willow canopy (FULL), partial herbicide clearance of the canopy (PARTIAL), and manual cutting of light wells (MANUAL). Saplings were planted as individuals or clusters of seven. Treatment plots were established in 2015 and monitored until 2020. Despite Kahikatea being considered a "light‐demanding" species, saplings grew best in the PARTIAL treatment which had the lowest ambient light levels (x̄=32% of non‐intercepted sunlight). PARTIAL treatment saplings were estimated to require 24–36 years to reach the height of the surrounding willow canopy if they maintained similar growth rates. Preconditioning saplings by soaking roots before planting provided a growth advantage in the PARTIAL treatment plots, whereas nonconditioned plants grew better in the higher‐light MANUAL and FULL plots. No benefit was found for cluster planting. Restoration toward a native Kahikatea‐dominated forest will be contingent on saplings reaching willow canopy height before the faster‐growing willows reestablish, or periodic management of willows to maintain light levels above the compensation point for continued growth. Ultimately, the utility of this approach depends on what on‐going facilitation is required and whether seedlings subsequently produced by these emergent podocarp "islands" are able to jump‐start a long‐term change in the successional trajectory of the surrounding willow‐dominated wetland. [ABSTRACT FROM AUTHOR]

The extraordinary adaptability and dispersal abilities have allowed Hyphantria cunea to expand its range, posing a great threat to urban landscapes and natural ecosystems. Searching for safe, efficient, and low-cost control methods may provide new strategies for pest management in H. cunea spread areas. In this study, based on the attraction of insects by preferred hosts, it was found that the response rates of virgin H. cunea female adults to Salix matsudana , Juglans mandshurica and Ulmus pumila were 89.17%, 97.92% and 93.98%, respectively. It was further found that this significant preference was mainly related to the volatiles m -xylene, o -xylene, dodecane and tetradecane found in the three species. Even though all four compounds at 10 μL/mL and 100 μL/mL had significant attractive effects on the virgin H. cunea female adults, m -xylene and dodecane at 100 μL/mL elicited significant EAG responses and tending behaviors by stimulating the olfactory receptor neurons (ORN A) of females, with response rates of 83.13% and 84.17%, while also having significant attractive effects on virgin male adults with rates of 65.74% and 67.51%. Therefore, both m -xylene and dodecane which at concentrations of 100 μL/mL had strong attractions to adults, could be used as the first choice of attractants for both sexes of H. cunea. This has important practical significance in reducing the frequency of H. cunea generations, limiting their population, controlling their spread range, and improving the efficiency of pest management in epidemic areas. [Display omitted] • m -Xylene, o -xylene, dodecane and tetradecane were the main active volatiles. • Four active volatiles stimulated olfactory receptor neurons of female adults. • Four active volatiles had attractive effects on female adults. • m -Xylene and dodecane can be both sexes attractants for integrated management. [ABSTRACT FROM AUTHOR]

Phosphorus (P) plays a crucial role in facilitating plant adaptation to cadmium (Cd) stress. However, the molecular mechanisms underlying P-mediated responses to Cd stress in roots remain elusive. This study investigates the effects of P on the growth, physiology, transcriptome, and metabolome of Salix caprea under Cd stress. The results indicate that Cd significantly inhibits plant growth, while sufficient P alleviates this inhibition. Under Cd exposure, P sufficiency resulted in increased Cd accumulation in roots, along with reduced oxidative stress levels (superoxide anion and hydrogen peroxide contents were reduced by 16.8% and 30.1%, respectively). This phenomenon can be attributed to the enhanced activities of antioxidant enzymes such as superoxide dismutase (SOD) and catalase (CAT), as well as increased levels of antioxidants including ascorbic acid (AsA) and flavonoids under sufficient P conditions. A total of 4208 differentially expressed genes (DEGs) and 552 differentially accumulated metabolites (DAMs) were identified in the transcriptomic and metabolomic analyses, with 2596 DEGs and 113 DAMs identified among treatments with different P levels under Cd stress, respectively. Further combined analyses reveal the potential roles of several pathways in P-mediated Cd detoxification, including flavonoid biosynthesis, ascorbate biosynthesis, and plant hormone signal transduction pathways. Notably, sufficient P upregulates the expression of genes including HMA , ZIP , NRAMP and CAX , all predicted to localize to the cell membrane. This may elucidate the heightened Cd accumulation under sufficient P conditions. These findings provide insights into the roles of P in enhancing plant resistance to Cd stress and improving of phytoremediation. [Display omitted] • Sufficient P enhances the resistance of Salix caprea roots to Cd stress. • Sufficient P enhances the activities of antioxidant enzyme such as SOD, CAT under Cd stress. • Flavonoids and ascorbic acid play important roles in the alleviation of Cd stress mediated by sufficient P. • Sufficient P increases Cd accumulation by up-regulating the expression of Cd transporter genes. [ABSTRACT FROM AUTHOR]

[Display omitted] • Using a non-toxic process to prepare biomass blue light emitting carbon quantum dots. • A new fluorescence cellulose hydrogel material with NCDs as core was synthesized. • The blue light emission of the fluorescence cellulose hydrogel can be applied to detect and absorb of heavy metal ions. • Providing an idea for construction of new hydrogel materials. To combat the contaminating effects of heavy-metal ions on water resources, we prepared blue photonitrogen-doped carbon quantum dots (NCDs) from Salix psammophila (SP) as a raw material, doped them into a microcrystalline cellulose hydrogel, and successfully created a composite hydrogel (NCDs-SP-MCC-gels) for concurrent fluorescence detection and Fe3+ adsorption. The NCDs-SP-MCC-gels was examined for their shape, chemical composition, fluorescence characteristics, and adsorption behaviors. Results demonstrated that the NCDs-SP-MCC-gels displayed a broad linear range of Fe3+ fluorescence response (200–1000 mg/L; detection limit = 3.90583 mg/L) and a high adsorption capacity for Fe3+ (610 mg/g). The adsorption data fitted the Langmuir and pseudo-second-order models well. Further research was conducted on Fe3+ detection and adsorption onto the NCDs-SP-MCC-gels. This study proposes a green and sustainable way to create a material for the detection and absorption of heavy-metal ions. [ABSTRACT FROM AUTHOR]

Gibberellin oxidases (GAoxs) identified from many species play indispensable roles in GA biosynthesis and GA signal transduction. However, there has been limited research conducted on the GAox family of Salix matsudana , a tetraploid ornamental tree species. Here, 54 GAox genes were identified from S. matsudana and renamed as SmGA20ox1–22 , SmGA2ox1–24 , SmGA3ox1–6 , and SmGAox-like1/2. Gene structure and conserved motif analysis showed that SmGA3ox members possess the 1 intron and other SmGAoxs contain 2–3 introns, and motif 1/2/7 universally present in all SmGAoxs. A total of 69 gene pairs were identified from SmGAox family members, and the Ka/Ks values indicated the SmGAoxs experience the purifying selection. The intra species collinearity analysis implied S. matsudana , S. purpurea , and Populus trichocarpa have the close genetic relationship. The GO analysis suggested SmGAoxs are dominantly involved in GA metabolic process, ion binding, and oxidoreductase activity. RNA-sequencing demonstrated that some SmGAox s may play an essential role in salt and submergence stresses. In addition, the SmGA20ox13/21 displayed the dominant vitality of GA20 oxidase, but the SmGA20ox13/21 still possessed low activities of GA2 and GA3 oxidases. This study can contribute to reveal the regulatory mechanism of salt and submergence tolerance in willow. • A total of 54 SmGAoxs were identified from the Salix matsudana genome. • SmGAoxs were involved in GA metabolic process, ion binding, and oxidoreductase activity. • The SmGA20ox13/21 displayed the dominant vitality of GA20 oxidase, but they still possessed low activities of GA2 and GA3 oxidases. [ABSTRACT FROM AUTHOR]

Vegetation in front of levees, dikes and seawalls can decrease wave energy and therefore contribute to the safety against flooding. However, wave damping predictions by vegetation are still inaccurate due to measurement and modelling uncertainties. Many studies focused on finding reliable predictive tools using scaled flume tests with vegetation mimics. Scaling down vegetation can however lead to discrepancies with realistic scales, known as scale errors. In this work scaled tests were conducted on 3D-printed elastic replicas of willow trees and compared with real-scale experiments. We identified differences in measured wave dissipation between the scaled hydraulic model (1:10) and its real-scale prototype with 5 m high live willow trees under storm conditions (1:1). The maximum measured wave damping (30%) was roughly 1.5 times higher than the real-scale experiments (20%). Following the same trend of the real-scale experiments, this amount of wave height damping declined for larger water levels. Largest effects are argued to be due to increased viscous damping (smaller branch Reynolds numbers) and non-exact flexibility scaling. These significant deviations illustrate that full-scale experiments, although expensive, are still needed to validate the results of scaled experiments for woody vegetation. Alternatively, accounting for these discrepancies can make scaled experiments more reliable and expensive real-scale experiments less needed for wave damping studies on woody vegetation. • A forest with Froude and Cauchy scaled mimics of real pollard willow trees with detailed multi-scale branch structure was 3D printed. • Wave damping for the specific tested scaled pollard willow forest increased by a factor 1.5 compared to a real-scale 40-m long forest: 30% instead of 20% wave height reduction. • The major scale and model effects are inferred to be viscous effects, and imperfect elasticity scaling, respectively, both having the same order of magnitude. • Branch deflection was observed for the real-scale and scaled tests with the scaled forest appearing too stiff. • For realistic multi-scale trees, turbulence processes are different for the different elements, and dimensionless numbers have a range of values for different parts. In this paper the main dimensionless numbers, Reynolds and Cauchy, were calculated for different parts of the trees. [ABSTRACT FROM AUTHOR]

Short rotation woody crops (SRWCs) have potential to provide sustainable aviation fuels and exceptional carbon fiber for numerous products. However, many SRWCs are riparian species and measuring water use will ensure that large-scale plantations do not negatively impact surrounding hydrology. Traditionally, willows (Salix spp.) have been important SRWCs in cooler regions like northern Europe and the northeastern US. However, black willow (Salix nigra Marshall) is native to the southeastern US and could be grown in sites that are marginal for poplar (Populus) including heavy clay soils that tend to remain flooded into the growing season. Our research goals were to measure diurnal water use and its correlation with environmental drivers as well as compare physiological parameters including whole-stem water use efficiency (WUE) and productivity across black willow genotypes planted in the Lower Mississippi Alluvial Valley. Across genotypes, yearly aboveground productivity, and whole-stem WUE were positively correlated with each other and were both positively correlated with stomatal sensitivity to vapor pressure deficit. Likewise, whole-stem WUE and leaf carbon isotope ratios were positively correlated suggesting that the latter can estimate whole-stem water use efficiencies for black willow. Atmospheric parameters and shallow groundwater levels were more important in explaining variation in daily water use than soil moisture implying that trees were tapping groundwater resources. In total, this research suggests that black willow is a water use efficient and promising bioenergy crop for the southeastern US, and more work currently underway will continue to develop genotypes and growing practices that maximize biomass production. • Whole-stem water use efficiency was 5 g kg−1, similar to other studies and species. • Water use efficiency and productivity were positively correlated in black willow. • Leaf carbon isotope ratios were correlated with whole-stem water use efficiency. • Sapflow was driven by the atmosphere and groundwater as opposed soil moisture. • Nitrogen isotope ratios were very positive suggesting high denitification [ABSTRACT FROM AUTHOR]

Shrub willow (Salix spp.) is increasingly grown as a biomass crop and for a range of environmental applications. Merging the economic and environmental objectives of willow production may facilitate more widespread adoption by reducing production costs and justifying willow cultivation in traditional agricultural settings. Incorporating willow in agricultural-riparian transition areas, particularly in intensive or high-input agricultural systems, can enhance watercourse protection from diffuse pollutants, mitigate indirect agricultural N 2 O emissions, and sequester carbon. However, biomass accrual and economic feasibility needs quantification on localized scales. This study investigated the biomass accrual of 9 agricultural-riparian willow buffers in Prince Edward Island, Canada, receiving no direct fertilization. Carbon, nitrogen, and phosphorus assimilation was measured in stem and root biomass, limitations on growth assessed, and benefit-cost analysis was conducted to determine opportunities for bioenergy use and deployment. First rotation agricultural-riparian Salix viminalis displayed considerable site-to-site variation in biomass production, with water availability being the primary limiting factor on growth. Mean total plant biomass and annual yield ranged from 0.54 to 7.9 kg dry matter plant−1 and 0.25–16.59 Mg ha−1 yr−1 (mean 3.9), respectively. CO 2 fixation was 0.67–46.64 Mg CO 2 ha−1 yr−1, of which 0.23–15.7 Mg CO 2 ha−1 yr−1 was root biomass, indicative of long-term sequestration. Nitrogen and phosphorus removal was 6.05–39.1 (mean 23.3) and 1.1–4.8 (mean 2.8) kg ha−1 yr−1. Benefit-cost analysis revealed that shrub willow production can be economically viable for on-farm heating when yields exceeding 5.6 Mg dry matter ha−1yr−1 are achieved, but off-farm sale is not currently economically justified. • Agricultural-riparian Salix viminalis biomass production was 0.25–16.59 Mg dry matter ha−1 yr−1. • Root biomass, indicative of long-term CO 2 sequestration, was 0.23–15.7 Mg CO 2 ha−1 yr−1. • Water availability was the main factor that limited biomass growth. • Salix viminalis with yields exceeding 5.6 Mg dry matter ha−1 yr−1 are economically viable as fuel for on-farm heating. [ABSTRACT FROM AUTHOR]

Aggravated metal pollution in wetland and riparian zones has become a global environmental issue, necessitating the identification of sustainable remediation approaches. Salix exhibits great potential as a viable candidate for metal(loid) remediation. However, the underlying mechanisms for its effectiveness in different flooding regimes with Pb pollution have not been extensively studied. In this study, fast-growing Salix×jiangsuensis 'J172' was selected and planted in different Pb polluted soils (control, 400 and 800 mg ∙ kg−1) under non-flooded and flooded (CF: continuous flooding and IF: intermittent flooding) conditions for 60 days. This study aimed to explore the effects of flooding on Salix growth performance, physiological traits, and the relationship between Pb uptake/translocation and root Fe plaques. Salix×jiangsuensis 'J172' exhibited excellent tolerance and adaptation to Pb pollution with a tolerance index (TI) exceeding 0.6, even at the highest Pb levels. Moreover, the TIs under flooded conditions were higher than that under non-flooded conditions, suggesting that flooding could alleviate Pb toxicity under co-exposure to Pb and flooding. Leaf malondialdehyde (MDA) exhibited a dose-dependent response to Pb exposure; however, CF or IF mitigated the oxidative damage induced by Pb toxicity with decreased MDA content (2.2–11.9%). The superoxide dismutase and peroxidase activities were generally enhanced by flooding, but combined stress (flooding and Pb) significantly decreased catalase activity. Pb was predominantly accumulated in Salix roots, and flooding markedly increased root Pb accumulation by 19.2–173.0% compared to non-flooded condition. Additionally, a significant positive correlation was observed between the iron (Fe) content of the root plaque and root Pb accumulation, indicating that the formation of Fe plaque on the root surface could enhance the phytostabilization of Pb in Salix. The current findings highlight that fast-growing woody plants are suitable for phyto-management of metal-polluted wetlands and can potentially minimize the risk of metal mobility in soils. [Display omitted] • Pb preferentially accumulated in Salix root and was markedly increased by flooding. • Continuous/intermittent flooding enhanced tolerance index and alleviated Pb toxicity to Salix. • Flooding mitigated the lipid peroxidation and activated antioxidant enzyme system in Salix. • Flooding and Pb stimulated the formation of Fe plaque on root surface. [ABSTRACT FROM AUTHOR]

This work investigates the proanthocyanidin profile of willow bark crude extracts and these materials were cationized and preliminarily tested as biocoagulants for water treatment. The characteristics of crude extracts proanthocyanidin were investigated using size exclusion chromatography (SEC), nuclear magnetic resonance (NMR) and X-ray photoelectron spectroscopy (XPS). XPS analysis indicates that the crude extracts contain significant amounts of sugars. Furthermore, SEC and liquid-state NMR spectroscopy showed that crude extract contains roughly 3–4 flavan-3-ol units with procyanidin (PC)/ prodelphinidin (PD) ratio of roughly 3–5. Thus, the modified form of tannin (proanthocyanidin-enriched) coagulants obtained the higher cationic charge density. The coagulation experiments with kaolin-river water mixture suggested that all the selected willow hybrids' tannin coagulants were effective in settling the particles down. This study indicates that the value of willow bark can be significantly improved by the usage of crude extracts for water treatment. [Display omitted] • Crude extracts from eight willow hybrids are characterized and Mannich modified. • The extract contains roughly 3-4 flavan-3-ol units with PC/PD ratio of roughly 3-5. • Modified proanthocyanidin-enriched extracts have medium cationic charge densities. • The biocoagulants were effective in settling the particles down from river water. [ABSTRACT FROM AUTHOR]

The phospholipid fatty acid (PLFA) composition of soils was analysed at three poplar-based silvo-arable systems and at one willow-based silvo-grassland alley agroforestry system in Central Germany. The objective was to analyse tree row effects on the PLFA composition of main fungal and main bacterial groups. The fungal groups were BAM (Basidiomycota + Ascomycota + Mucoromycota) and AMF (Arbuscular Mycorrhizal Fungi). The bacterial groups were Gram-negative, Firmicutes, and Actinobacteria. The total PLFA content varied between 53 and 170 nmol g−1 soil. Total PLFA and microbial biomass carbon (MBC) showed a strong linear relationship, which resulted in a mean MBC/total PLFA ratio of 4.2 μg nmol−1. AMF contributed on average 4 mol% and the fungal BAM group 10 % to total PLFA. Gram-negative bacteria contributed on average 37 mol%, Firmicutes 23 mol%, and Actinobacteria 6 mol% to total PLFA. The presence of poplar or willow trees increased the mean total PLFA content in comparison with the alleyways by 30 %. Especially the mean contribution of fungal PLFA to total PLFA showed a significant +7.0 mol% increase in the tree row compared with the alleyways, exclusively caused by the BAM group (+7.6 mol%), whereas the contribution of the AMF PLFA linearly decreased from the middle of the alleyway to the tree row at all sites. Within the alleyways, the Gram-negative/Firmicutes PLFA ratio showed a significant decline from the 1 m up to the 24 m distance samples at sites Dornburg and Forst. Despite a decrease of AMF in tree rows, agroforestry tree rows led to a rapid increase in fungi, most likely due to the promotion of ecto-mycorrhizal fungi. • Tree rows shifted the PLFA composition to more fungal biomarkers. • Bacterial PLFA diversity was higher in the arable alleyways than in the tree rows. • PLFA composition contrasts bacterial gene abundance, especially for Actinobacteria. • Agroforestry generally supports the C sequestration potential of mycorrhizal fungi. [ABSTRACT FROM AUTHOR]

The investigation examined the use of willow leaf extract (WLE) on broiler chickens, examining carcass characteristics, cecal microbiota, antioxidants, and blood parameters. In 4 groups of 300 chicks, a basal diet was given for 5 wk, and the first treatment was basal diet (C). The diets for the remaining 3 treatments (WLE150, WLE300, and WLE450) contained 150, 300, and 450 mg of willow leaf extract /kg, respectively. The study found that birds fed willow leaf extract supplements had significantly greater body weight (BW), body weight gain (BWG), and enhanced feed conversion ratio (FCR) vs. the control group. Birds fed at 450 mg/kg food showed the greatest growth features, carcass weight, liver weight, lower abdominal fat, better low-density lipoprotein (LDL), and high-density lipoprotein (HDL) concentrations, and highest hematological characteristics. Chickens fed diets supplemented with varied doses of willow leaf extract showed significantly increased antioxidant enzyme activity, with higher amounts of glutathione peroxidase (GPx) activity, superoxide dismutase (SOD), total antioxidant capacity (TAC), and lower malondialdehyde (MDA). However, in the study, birds fed a diet supplemented with 450 mg of willow leaf extract per kg meal showed a significant drop of 13.02%, which found no significant variations in hazardous bacteria (Escherichia coli) across 2 treatments (WLE150 and WLE300). In addition, the study discovered that birds fed with varied doses of willow leaf extract had fewer cecum infections (Staphylococci aureus). We conclude that using willow at a level of 450 mg/kg diet can significantly enhance the BWG, FCR, antioxidant levels and beneficial bacteria activity besides the condition of broiler chicken's general health. [ABSTRACT FROM AUTHOR]

Development of low-temperature NO 2 sensors has recently gained extensive interests. However, how to realize their over-all sensing abilities of high response and rapid detection is still challenging. Herein, adhering to the concept of sustainable development, waste willow catkins have been selected as template and soaked in Zn/In nitrates solution with two types of molar ratios. Then, the obtained precursors were placed in a furnace to undergo calcination at 500 ℃, generating two biomorphic In 2 O 3 /ZnO heterogeneous microtubes. All the tubes were assembled by well-crystallized small-size nanoparticles. Thereinto, 16.4 wt% In 2 O 3 /ZnO sensor exhibits well comprehensive gas-sensing performances towards trace NO 2 at low 92 °C. That is, its response value (S = 883) and recovery time (10 s) to 10 ppm NO 2 are higher and faster than those of most one-dimensional ZnO-based NO 2 sensors reported so far. Meanwhile, it also has good selectivity and low detection limit (10 ppb), as well as satisfactory long-term stability and humidity resistance. Therefore, the mesoporous 16.4 wt% In 2 O 3 /ZnO heterogeneous microtubes rich in oxygen vacancy defects are available as a candidate for detecting trace NO 2 at low temperature. [Display omitted] • In 2 O 3 /ZnO hetero-tubes rich in oxygen vacancies were simply prepared using waste catkins as template. • The synergism of multiple favorable structure factors answers for well over-all gas-sensing performance. • At 92 °C, 16.4 wt% In 2 O 3 /ZnO shows the highest response to NO 2 among 1-D ZnO-based sensors. • The simple and sustainable biotemplate method offers a new way for preparing tubular metal oxides. [ABSTRACT FROM AUTHOR]

Trace metals have relatively high density and high toxicity at low concentrations. Willow (Salix genus) is an excellent phytoremediation species for soil contaminated by trace metal ions. This study identified a cell number regulator (CNR) gene family member in Salix linearistipularis exhibiting strong metal ion resistance: SlCNR8. SlCNR8 expression was affected by various metal ions, including cadmium (Cd), zinc (Zn), copper (Cu), iron (Fe), and manganese (Mn). SlCNR8 overexpression enhanced Cd, Zn, Cu, and Fe resistance in transgenic poplar seedlings (84K) compared with the wild-type (WT). Moreover, transgenic poplar seedlings showed lower root Cd uptake and less Cd accumulation than WT under Cd stress. SlCNR8 was primarily localized to the nucleus and the plasma membrane-like cell periphery. Furthermore, SlCNR8 had transcriptional activation activity in yeast. The transcript levels of multiple metal ion transporters were altered in the roots of transgenic poplar seedlings compared to WT roots under Cd stress. These results suggest that SlCNR8 may enhance Cd resistance in transgenic poplar by reducing Cd uptake and accumulation. This may be related to altered transcription levels of other transporters or to itself. Our study suggests that SlCNR8 can be used as a candidate gene for genetic improvement of phytostabilisation of trace metals by genetic engineering. • SlCNR8 overexpression enhances Cd, Zn, Cu and Fe resistance in transgenic poplar. • SlCNR8 affects the Cd uptake and accumulation. • SlCNR8 was primarily localized to the nucleus and the plasma membrane-like cell periphery. [ABSTRACT FROM AUTHOR]

Nitrogen (N) partitioning between trees and crops in alley-cropping systems (AC) may increase the N fertilizer use, but more investigation is needed to elucidate it for young trees. The aim of this study was to explore the share of N between crops and three tree species after a few years of tree establishment in AC. Using 15N labeling (10 atm% as 15NH 4 ,15NO 3 form), we traced the fate of N fertilizer in wheat associated with four-year-old trees at Ramecourt alley-cropping experimental site. The 15N abundance of tree leaves and crop whole-plant was compared between samples collected in AC, in sole-crop control (CC) and in unlabeled and unfertilized pure-forest control plots (FC). The wheat δ15N increased from 0.7 ± 0.6‰ to 994 ± 474‰ before and 12 days after labeling and remained stable until harvest. For natural abundance, no significant difference in wheat δ15N was observed between AC and CC. The same result was observed for labeled treatment. The percentage of wheat N derived from fertilizer was on average 27 ± 17% and no effect of type of system or associated tree species was observed. Tree foliar δ15N was multiplied by 1.5, 1.8 and 4 for willow, hornbeam and wild cherry respectively compared to unlabeled trees in AC. The percentage of tree foliar N derived from fertilizer was on average 0.04 ± 0.04% and no significant difference was observed between tree species. The wheat associated with trees allocated significantly more tracer N to ears than wheat in monocrop. From this study, we succeeded in quantifying the beginning of tree/crop sharing of N fertilizer using labeling method and evidenced tree species effect. Young trees in AC contributed to valorize the N fertilizer without significant effect on global wheat uptake and favored its valorization in wheat grain. • 15N labeling was used to trace the share of N between crop and four-year-old trees. • The fraction of wheat N derived from fertilizer (27 ± 17%) was not affected by trees. • In AC, foliar δ15N was 4 times higher for labeled wild cherry than unlabeled trees. • The percentage of tree foliar N derived from fertilizer was on average 0.04 ± 0.04%. • Wheat in AC allocated significantly more tracer N to ears than wheat in monocrop. [ABSTRACT FROM AUTHOR]