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<jats:p>There is a large demand to reduce inputs for current crop production, particularly phosphate and nitrogen inputs which are the two most frequently added supplements to agricultural production. Gene characterization is often limited to the native species from which it was identified, but may offer benefits to other species. To understand if the rice gene Phosphate Starvation Tolerance 1 (PSTOL) <jats:italic>OsPSTOL</jats:italic>, a gene identified from rice which improves tolerance to low P growth conditions, might improve performance and provide the same benefit in wheat, <jats:italic>OsPSTOL</jats:italic> was transformed into wheat and expressed from a constitutive promoter. The ability of <jats:italic>OsPSTOL</jats:italic> to improve nutrient acquisition under low phosphate or low nitrogen was evaluated. Here we show that <jats:italic>OsPSTOL</jats:italic> works through a conserved pathway in wheat and rice to improve yields under both low phosphate and low nitrogen. This increase is yield is mainly driven by improved uptake from the soil driving increased biomass and ultimately increased seed number, but does not change the concentration of N in the straw or grain. Overexpression of <jats:italic>OsPSTOL</jats:italic> in wheat modifies N regulated genes to aid in this uptake whereas the putative homolog <jats:italic>TaPSTOL</jats:italic> does not suggesting that expression of <jats:italic>OsPSTOL</jats:italic> in wheat can help to improve yields under low input agriculture.</jats:p>

<jats:p>Tea is a vital beverage crop all over the world, including in China. Low temperatures restrict its growth, development, and terrestrial distribution, and cold event variability worsens cold damage. However, the physiological and molecular mechanisms of <jats:italic>Camellia sinensis</jats:italic> under shade in winter remain unclear. In our study, tea leaves were utilized for physiological attributes and transcriptome analysis in November and December in three shading groups and no-shade control plants. When compared to the no-shade control plants, the shading group protected tea leaves from cold damage, increased photochemical efficiency (Fv/Fm) and soil plant analysis development (SPAD), and sustained chlorophyll <jats:italic>a</jats:italic>, chlorophyll <jats:italic>b</jats:italic>, chlorophyll, and carotenoid contents by physiological mean. Then, transcriptome analysis revealed 20,807 differentially expressed genes (DEGs) and transcription factors (TFs) in November and December. A comparative study of transcriptome resulted in 3,523 DEGs and many TFs under SD0% <jats:italic>vs.</jats:italic> SD30%, SD0% <jats:italic>vs.</jats:italic> SD60%, and SD0% <jats:italic>vs.</jats:italic> SD75% of shading in November and December. Statistically, 114 DEGs were downregulated and 72 were upregulated under SD0% <jats:italic>vs.</jats:italic> SD30%. SD0% <jats:italic>vs.</jats:italic> SD60% resulted in 154 DEGs, with 60 downregulated and 94 upregulated. Similarly, there were 505 DEGs of which 244 were downregulated and 263 were upregulated under SD0% <jats:italic>vs.</jats:italic> SD75% of shading throughout November. However, 279 DEGs were downregulated and 105 were upregulated under SD0% <jats:italic>vs.</jats:italic> SD30%. SD0% <jats:italic>vs.</jats:italic> SD60% resulted in 296 DEGs, with 172 downregulated and 124 upregulated. Finally, 2,173 DEGs were regulated in December, with 1,428 downregulated and 745 upregulated under SD0% <jats:italic>vs.</jats:italic> SD75%. These indicate that the number of downregulated DEGs in December was higher than the number of upregulated DEGs in November during low temperatures. Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) analyses of differentially expressed genes were highly regulated in the photosynthesis, plant hormone signal transduction, and mitogen-activated protein kinase (MAPK) signaling pathways. However, qRT-PCR and RNA-seq relative expression of photosynthetic (DEGs) <jats:italic>Lhcb2</jats:italic> in both November and December, plant hormone (DEGs) <jats:italic>BRI1</jats:italic> and <jats:italic>JAZ</jats:italic> in November and <jats:italic>IAA</jats:italic> and <jats:italic>ERF1</jats:italic> in December, and key DEGs of MAPK signal transduction <jats:italic>FLS2</jats:italic>, <jats:italic>CHIB</jats:italic>, and <jats:italic>MPK4</jats:italic> in November and <jats:italic>RBOH</jats:italic>, <jats:italic>MKK4_5</jats:italic>, and <jats:italic>MEKK1</jats:italic> in December in three shading groups and no-shade control plants responded to tea cold tolerance. The enhanced expression of light-harvesting photosystem I gene <jats:italic>Lhca5</jats:italic>, light-harvesting photosystem II gene <jats:italic>Lhcb2</jats:italic>, and mitogen-activated protein kinases <jats:italic>MEKK1</jats:italic> and <jats:italic>MPK4/6</jats:italic> enhance the cold-tolerance mechanism of <jats:italic>C. sinensis</jats:italic>. These comprehensive transcriptomic findings are significant for furthering our understanding of the genes and underlying regulatory mechanisms of shade-mediated low-temperature stress tolerance in horticultural crops.</jats:p>

<jats:p>The rapid increase in population growth under changing climatic conditions causes drought stress, threatening world food security. The identification of physiological and biochemical traits acting as yield-limiting factors in diverse germplasm is pre-requisite for genetic improvement under water-deficit conditions. The major aim of the present study was the identification of drought-tolerant wheat cultivars with a novel source of drought tolerance from local wheat germplasm. The study was conducted to screen 40 local wheat cultivars against drought stress at different growth stages. Barani-83, Blue Silver, Pak-81, and Pasban-90 containing shoot and root fresh weight &amp;gt;60% of control and shoot and root dry weight &amp;gt;80% and 70% of control, respectively, P (% of control &amp;gt;80 in shoot and &amp;gt;88 in root), K<jats:sup>+</jats:sup> (&amp;gt;85% of control), and quantum yield of PSII &amp;gt; 90% of control under polyethylene glycol (PEG)-induced drought stress at seedling stage can be considered as tolerant, while more reduction in these parameters make FSD-08, Lasani-08, Punjab-96, and Sahar-06 as drought-sensitive cultivars. FSD-08 and Lasani-08 could not maintain growth and yield due to protoplasmic dehydration, decreased turgidity, cell enlargement, and cell division due to drought treatment at adult growth stage. Stability of leaf chlorophyll content (&amp;lt;20% decrease) reflects photosynthetic efficiency of tolerant cultivars, while ~30 µmol/g fwt concentration of proline, 100%–200% increase in free amino acids, and ~50% increase in accumulation of soluble sugars were associated with maintaining leaf water status by osmotic adjustment. Raw OJIP chlorophyll fluorescence curves revealed a decrease in fluorescence at O, J, I, and P steps in sensitive genotypes FSD-08 and Lasani-08, showing greater damage to photosynthetic machinery and greater decrease in JIP test parameters, performance index (PI<jats:sub>ABS</jats:sub>), maximum quantum yield (Fv/Fm) associated with increase in Vj, absorption (ABS/RC), and dissipation per reaction center (DIo/RC) while a decrease in electron transport per reaction center (ETo/RC). During the present study, differential modifications in morpho-physiological, biochemical, and photosynthetic attributes that alleviate the damaging effects of drought stress in locally grown wheat cultivars were analyzed. Selected tolerant cultivars could be explored in various breeding programs to produce new wheat genotypes with adaptive traits to withstand water stress.</jats:p>

<jats:p>Drought is a major constraint in wheat (<jats:italic>Triticum aestivum L.</jats:italic>) grain yield. The present work aimed to identify quantitative trait nucleotides (QTNs)/ candidate genes influencing drought tolerance-related traits at the seedling stage in 261 accessions of a diverse winter wheat panel. Seeds from three consecutive years were exposed to polyethylene glycol 12% (PEG-6000) and a control treatment (distilled water). The Farm-CPU method was used for the association analysis with 17,093 polymorphic SNPs. PEG treatment reduced shoot length (SL) (-36.3%) and root length (RL) (-11.3%) compared with control treatments, while the coleoptile length (CL) was increased by 11% under drought conditions, suggesting that it might be considered as an indicator of stress-tolerance. Interestingly, we revealed 70 stable QTN across 17 chromosomes. Eight QTNs related to more than one trait were detected on chromosomes 1B, 2A (2), 2B, 2D, 4B, 7A, and 7B and located nearby or inside candidate genes within the linkage disequilibrium (LD) interval. For instance, the QTN on chromosome 2D is located inside the gene TraesCS2D02G133900 that controls the variation of CL_S and SL_C. The allelic variation at the candidate genes showed significant influence on the associated traits, demonstrating their role in controlling the natural variation of multi-traits of drought stress tolerance. The gene expression of these candidate genes under different stress conditions validates their biological role in stress tolerance. Our findings offer insight into understanding the genetic factors and diverse mechanisms in response to water shortage conditions that are important for wheat improvement and adaptation at early developmental stages.</jats:p>

<jats:sec><jats:title>Introduction</jats:title><jats:p>The establishment of invasive alien plants (IAPs) is primarily driven by climate warming and human activities, and their populations have a negative impact on agricultural economics, ecological systems, and human health. <jats:italic>Lolium temulentum</jats:italic> and <jats:italic>Aegilops tauschii</jats:italic> are critical IAPs in China because they reduce the quality of cereal grains and decrease wheat yields. <jats:italic>Lolium temulentum</jats:italic> is a winter-temperate weed that spreads easily and is poisonous to humans and animals. <jats:italic>Aegilops tauschii</jats:italic> is resistant to herbicides, has a high reproductive rate, and frequently grows in wheat. Both species have been listed in the Ministry of Agriculture and Rural Affairs of the People’s Republic of China’s management catalog since 2006.</jats:p></jats:sec><jats:sec><jats:title>Methods</jats:title><jats:p>In the present study, the historical occurrence and invasion of each species were collected and reconstructed, which showed that the population outbreak of <jats:italic>L. temulentum</jats:italic> began in 2010, whereas that of <jats:italic>A. tauschii</jats:italic> began in 2000. Using the optimal MaxEnt model, the geographical distributions of <jats:italic>L. temulentum</jats:italic> and <jats:italic>A. tauschii</jats:italic> were predicted based on screened species occurrences and environmental variables under the current and three future scenarios in the 2030s and 2050s (i.e., SSP1-2.6, SSP2-4.5, and SSP5-8.5).</jats:p></jats:sec><jats:sec><jats:title>Results</jats:title><jats:p>The mean AUC values were 0.867 and 0.931 for <jats:italic>L. temulentum</jats:italic> and <jats:italic>A. tauschii</jats:italic>, respectively. Human influence index (HII), mean temperature of coldest quarter (bio11), and precipitation of coldest quarter (bio19) were the most significant variables for <jats:italic>L. temulentum</jats:italic>, whereas human influence index, temperature seasonality (standard deviation×100) (bio4), and annual mean temperature (bio1) were the critical environmental variables for <jats:italic>A. tauschi.</jats:italic> Suitable habitat areas in China for <jats:italic>L. temulentum</jats:italic> and <jats:italic>A. tauschii</jats:italic> currently covered total areas of 125 × 10<jats:sup>4</jats:sup> and 235 × 10<jats:sup>4</jats:sup> km<jats:sup>2</jats:sup>, respectively. Future suitable areas of <jats:italic>L. temulentum</jats:italic> reached the maximum under SSP2-4.5, from 2021 to 2060, whereas for <jats:italic>A. tauschii</jats:italic> they reached the maximum under SSP5-8.5, from 2021 to 2060. Furthermore, the overlap area under the current climate conditions for <jats:italic>L. temulentum</jats:italic> and <jats:italic>A. tauschii</jats:italic> was approximately 90 × 10<jats:sup>4</jats:sup> km<jats:sup>2</jats:sup>, mainly located in Hubei, Anhui, Jiangsu, Shandong, Henan, Shaanxi, Shanxi, and Hebei. The overlap areas decreased in the 2030s, increased in the 2050s, and reached a maximum under SSP1-2.6 (or SSP2-4.5) with an approximate area of 104 × 10<jats:sup>4</jats:sup> km<jats:sup>2</jats:sup>. The centroid of <jats:italic>L. temulentum</jats:italic> in Henan was transferred to the southwest, whereas for <jats:italic>A. tauschii</jats:italic> it transferred to higher latitudes in the northeast.</jats:p></jats:sec><jats:sec><jats:title>Discussion</jats:title><jats:p>Our findings provide a practical reference for the early warning, control, and management of these two destructive IAP populations in China.</jats:p></jats:sec>

<jats:p><jats:italic>Hibiscus syriacus</jats:italic>, a member of the tribe Hibisceae, is considered an important ornamental and medicinal plant in east Asian countries. Here, we sequenced and assembled the complete chloroplast genome of <jats:italic>H. syriacus</jats:italic> var. <jats:italic>Baekdansim</jats:italic> using the PacBio long-read sequencing platform. A quadripartite structure with 161,026 base pairs was obtained, consisting of a pair of inverted repeats (IRA and IRB) with 25,745 base pairs, separated by a large single-copy region of 89,705 base pairs and a short single-copy region of 19,831 base pairs. This chloroplast genome had 79 protein-coding genes, 30 transfer RNA genes, 4 ribosomal RNA genes, and 109 simple sequence repeat regions. Among them, <jats:italic>ndhD</jats:italic> and <jats:italic>rpoC1</jats:italic>, containing traces of RNA-editing events associated with adaptive evolution, were identified by analysis of putative RNA-editing sites. Codon usage analysis revealed a preference for A/U-terminated codons. Furthermore, the codon usage pattern had a clustering tendency similar to that of the phylogenetic analysis of the tribe Hibisceae. This study provides clues for understanding the relationships and refining the taxonomy of the tribe Hibisceae.</jats:p>

<jats:p>Heat stress is poised to become a major factor negatively affecting plant performance worldwide. In terms of world food security, increased ambient temperatures are poised to reduce yields in cereals and other economically important crops. Grain amaranths are known to be productive under poor and/or unfavorable growing conditions that significantly affect cereals and other crops. Several physiological and biochemical attributes have been recognized to contribute to this favorable property, including a high water-use efficiency and the activation of a carbon starvation response. This study reports the behavior of the three grain amaranth species to two different stress conditions: short-term exposure to heat shock (HS) conditions using young plants kept in a conditioned growth chamber or long-term cultivation under severe heat stress in greenhouse conditions. The latter involved exposing grain amaranth plants to daylight temperatures that hovered around 50°C, or above, for at least 4 h during the day and to higher than normal nocturnal temperatures for a complete growth cycle in the summer of 2022 in central Mexico. All grain amaranth species showed a high tolerance to HS, demonstrated by a high percentage of recovery after their return to optimal growing conditions. The tolerance observed coincided with increased expression levels of unknown function genes previously shown to be induced by other (a)biotic stress conditions. Included among them were genes coding for RNA-binding and RNA-editing proteins, respectively. HS tolerance was also in accordance with favorable changes in several biochemical parameters usually induced in plants in response to abiotic stresses. Conversely, exposure to a prolonged severe heat stress seriously affected the vegetative and reproductive development of all three grain amaranth species, which yielded little or no seed. The latter data suggested that the usually stress-tolerant grain amaranths are unable to overcome severe heat stress-related damage leading to reproductive failure.</jats:p>

<jats:p>Freezing damage has been a common natural disaster for tea plantations. Quantitative detection of low temperature stress is significant for evaluating the degree of freezing injury to tea plants. Traditionally, the determination of physicochemical parameters of tea leaves and the investigation of freezing damage phenotype are the main approaches to detect the low temperature stress. However, these methods are time-consuming and laborious. In this study, different low temperature treatments were carried out on tea plants. The low temperature response index (LTRI) was established by measuring seven low temperature-induced components of tea leaves. The hyperspectral data of tea leaves was obtained by hyperspectral imaging and the feature bands were screened by successive projections algorithm (SPA), competitive adaptive reweighted sampling (CARS) and uninformative variable elimination (UVE). The LTRI and seven indexes of tea plant were modeled by partial least squares (PLS), support vector machine (SVM), random forests (RF), back propagation (BP) machine learning methods and convolutional neural networks (CNN), long short-term memory (LSTM) deep learning methods. The results indicated that: (1) the best prediction model for the seven indicators was LTRI-UVE-CNN (R<jats:sup>2 =</jats:sup> 0.890, RMSEP=0.325, RPD=2.904); (2) the feature bands screened by UVE algorithm were more abundant, and the later modeling effect was better than CARS and SPA algorithm; (3) comparing the effects of the six modeling algorithms, the overall modeling effect of the CNN model was better than other models. It can be concluded that out of all the combined models in this paper, the LTRI-UVE-CNN was a promising model for predicting the degree of low temperature stress in tea plants.</jats:p>

<jats:p>Spider mite infestations are a serious hazard for jujube trees in China. The use of remote sensing technology to evaluate the health of jujube trees in large-scale intensive agricultural production is an effective means of agricultural control. Hyperspectral remote sensing has a higher spectral resolution and richer spectral information than conventional multispectral remote sensing, which improves the detection of crop pests and diseases. We used hyperspectral remote sensing data from jujube fields infested with spider mite in Hotan Prefecture, Xinjiang to evaluate their use in monitoring this important pest. We fused spectral and spatial information from the hyperspectral images and propose a method of recognizing spider mite infestations of jujube trees. Our method is based on the construction of spectral features, the fusion of spatial information and clustering of these spectral–spatial features. We evaluated the effect of different spectral–spatial features and different clustering methods on the recognition of spider mite in jujube trees. The experimental results showed that the overall accuracy of the method for the recognition of spider mites was &amp;gt;93% and the overall accuracy of the band clustering–density peak clustering model for the recognition of spider mite reached 96.13%. This method can be applied to the control of jujube spider mites in agricultural production.</jats:p>

<jats:p>Pectin- and hemicellulose-associated structures of plant cell walls participate in defense responses against pathogens of different parasitic lifestyles. The resulting immune responses incorporate phytohormone signaling components associated with salicylic acid (SA) and jasmonic acid (JA). SA plays a pivotal role in systemic acquired resistance (SAR), a form of induced resistance that - after a local immune stimulus - confers long-lasting, systemic protection against a broad range of biotrophic invaders. β-D-XYLOSIDASE 4 (BXL4) protein accumulation is enhanced in the apoplast of plants undergoing SAR. Here, two independent <jats:italic>Arabidopsis thaliana</jats:italic> mutants of <jats:italic>BXL4</jats:italic> displayed compromised systemic defenses, while local resistance responses to <jats:italic>Pseudomonas syringae</jats:italic> remained largely intact. Because both phloem-mediated and airborne systemic signaling were abrogated in the mutants, the data suggest that BXL4 is a central component in SAR signaling mechanisms. Exogenous xylose, a possible product of BXL4 enzymatic activity in plant cell walls, enhanced systemic defenses. However, GC-MS analysis of SAR-activated plants revealed BXL4-associated changes in the accumulation of certain amino acids and soluble sugars, but not xylose. In contrast, the data suggest a possible role of pectin-associated fucose as well as of the polyamine putrescine as regulatory components of SAR. This is the first evidence of a central role of cell wall metabolic changes in systemic immunity. Additionally, the data reveal a so far unrecognized complexity in the regulation of SAR, which might allow the design of (crop) plant protection measures including SAR-associated cell wall components.</jats:p>