Environmental and Experimental Botany最新文献

{"title":"A novel NAC transcription factor from Haloxylon ammodendron promotes reproductive growth in Arabidopsis thaliana under drought stress","authors":"Jianshun Liang ,&nbsp;Xiashun Liu ,&nbsp;Lei Xu ,&nbsp;Rongbo Mu ,&nbsp;Nengshuang Shen ,&nbsp;ShanShan Li ,&nbsp;Cong Cheng ,&nbsp;Yanping Ren ,&nbsp;Li Ma ,&nbsp;Bo Wang ,&nbsp;Zhengpei Yao ,&nbsp;Hua Zhang","doi":"10.1016/j.envexpbot.2024.106043","DOIUrl":"10.1016/j.envexpbot.2024.106043","url":null,"abstract":"<div><div>Maintaining the growth of reproductive branches during the summer is crucial for the seed setting of the perennial xerophytic plant <em>H. ammodendron</em> (<em>Haloxylon ammodendron</em>). In this study, we screened and cloned the NAC transcription factor <em>HaNAC12</em> from the transcriptomes of different tissue of the desert plant <em>H. ammodendron</em> and from the transcriptome of seedlings under drought stress. Real-time quantitative fluorescence analysis showed that the expression level of <em>HaNAC12</em> in reproductive branches was higher than that in vegetative branches. It was able to respond to treatments of drought, high salinity and low-temperature stress, as well as to the external induction of plant hormones such as IAA, ABA, SA and MeJA. The GFP- <em>HaNAC12</em> fusion protein localized to the nucleus of tobacco epidermal cells. Heterologous expression of <em>HaNAC12</em> revealed that the transgenic <em>Arabidopsis</em> exhibited enhanced drought resistance and showed early flowering after natural drought stress, promoting reproductive growth. Transcriptomic analysis indicated that fatty acid metabolic pathways were upregulated in transgenic <em>Arabidopsis thaliana</em>. DNA affinity purification analysis showed that HANAC12 binds to elements in the downstream target genes primarily associated with the linoleic acid metabolic pathway. The total fatty acid content in the reproductive branches of transgenic <em>Arabidopsis</em> and <em>H. ammodendron</em> is greater than that in the wild-type <em>Arabidopsis</em> and the vegetative branches of <em>H. ammodendron</em>. Under drought stress, plants can adapt to arid conditions by increasing the proportion of unsaturated fatty acids, thereby enhancing membrane fluidity, reducing membrane damage, and maintaining the requirements for cell division and growth. Therefore, <em>HaNAC12</em> may improve the drought resistance of <em>Arabidopsis</em> and promote reproductive growth under drought stress by regulating fatty acid metabolism.</div></div>","PeriodicalId":11758,"journal":{"name":"Environmental and Experimental Botany","volume":"228 ","pages":"Article 106043"},"PeriodicalIF":4.5,"publicationDate":"2024-11-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142700709","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Grafting semi-wild tomato GZ-05 rootstocks improved cold tolerance via the signalling of melatonin and jasmonic acid","authors":"Jianming Wei ,&nbsp;Yunzhou Li ,&nbsp;Ping Tan ,&nbsp;Dalong Zhang ,&nbsp;Yan Liang","doi":"10.1016/j.envexpbot.2024.106042","DOIUrl":"10.1016/j.envexpbot.2024.106042","url":null,"abstract":"<div><div>Tomato (<em>Solanum lycopersicum</em>) cultivation in the off-season is significantly hindered by cold stress; hence, utilising stress-resistant rootstocks in grafting is a critical solution. This study used 30 semi-wild tomato GZ-05 plants as rootstocks and Ailsa Craig (AC) tomatoes as scions. After cold stress, the scion tolerance index, leaf ion permeability, and other physiological and biological indicators were used to determine the most tolerant plants. To understand the molecular basis of GZ-05 rootstock cold stress resistance, RNA sequencing and reverse transcription polymerase chain reaction techniques were used to compare the varying genes expressed in the grafted AC/GZ-05 and self-grafted AC/AC plant scion leaves. The results indicated that genes associated with melatonin (MT) and jasmonic acid (JA) production and their signalling pathways were considerably altered. The initial MT and JA levels in the GZ-05-grafted plant scions were high, and when they were exposed to cold stress, the amount of active MT and JA in AC/GZ-05 heterologous grafts were great. Using clustered regularly interspaced short palindromic repeats (CRISPR)/CRISPR-associated protein 9, we knocked out the MT synthesis gene (<em>SlCOMT14</em>) and JA synthesis gene (<em>SlLoxD</em>) and found that GZ-05 plant cold stress tolerance decreased. External tests were conducted to evaluate the GZ-05 <em>SlCOMT14</em> and <em>SlLoxD</em> knockout lines. Source spraying with MT and methyl jasmonate showed that knockout strain cold stress tolerance could be recovered. SlICE1, a tomato cold stress tolerance transcription factor, was silenced, resulting in decreased tolerance to MT- and JA-induced cold stress. The MT/JA-inducer of C-repeat binding factor (CBF) expression 1-CBF pathway may be the mechanism by which the semi-wild tomato GZ-05 rootstock confers cold tolerance to plants. This study has uncovered the molecular mechanism by which grafting semi-wild tomato GZ-05 rootstocks increases plant cold tolerance, thereby laying the groundwork for the utilisation of Guizhou's native semi-wild tomato germplasm resources.</div></div>","PeriodicalId":11758,"journal":{"name":"Environmental and Experimental Botany","volume":"228 ","pages":"Article 106042"},"PeriodicalIF":4.5,"publicationDate":"2024-11-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142700708","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Nutrient mediation of sink strength in the Orobanche minor – Red clover association","authors":"Mao Hattori,&nbsp;Clarissa Frances Frederica ,&nbsp;Louis John Irving","doi":"10.1016/j.envexpbot.2024.106041","DOIUrl":"10.1016/j.envexpbot.2024.106041","url":null,"abstract":"<div><div>Holoparasites are non-photosynthetic plants which derive all their growth requirements from their host plant and are thought to act as a very strong sink for host resources. Here, we grew red clover plants in split-root boxes to explore the effect of nutrient supply to <em>Orobanche minor</em> parasitized or unparasitized host roots. Where nutrients were supplied to parasitized roots, parasite growth was strongly promoted at the expense of the host. Conversely, host growth did not differ significantly from unparasitized controls where nutrients were supplied to unparasitized roots. While ¹⁵N labelling suggested both strong parasitic ammonium abstraction and reduced nitrate uptake in parasitized roots, the total N content of systems where nutrients were fed to parasitized roots was approximately 26 % higher than control plants, suggesting that changes in host and parasite growth rates were due to changes in sink strength, rather than nutrient uptake. Parasitism and nutrient supply had strong effects on leaf carbohydrate metabolism but did not affect photosynthetic rates or leaf N concentration. In the second experiment, we investigated the importance of light level on the host – parasite relationship, concluding that parasitism had a diminished effect on host growth under low light conditions. Total system mass was unaffected by the apparent sink strength of the parasite. Our results suggest a dynamic relationship between host shoot and parasite sink strengths, mediated by changes in nutrient status.</div></div>","PeriodicalId":11758,"journal":{"name":"Environmental and Experimental Botany","volume":"228 ","pages":"Article 106041"},"PeriodicalIF":4.5,"publicationDate":"2024-11-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142654395","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Fast chlorophyll fluorescence rise kinetics as a high-throughput diagnostic tool for evaluating the capacity of 2-amino-3-methylhexanoic acid at inducing plant resistance against high temperature","authors":"Jingjing Li ,&nbsp;Haiou Liu ,&nbsp;Yanjing Guo ,&nbsp;Yuan Chang ,&nbsp;Jing Zhang ,&nbsp;He Wang ,&nbsp;Qing Liu ,&nbsp;Yu Ji ,&nbsp;Zheng Zhang ,&nbsp;Yujing Liu ,&nbsp;Bernal E. Valverde ,&nbsp;Shiguo Chen","doi":"10.1016/j.envexpbot.2024.106040","DOIUrl":"10.1016/j.envexpbot.2024.106040","url":null,"abstract":"<div><div>Plant resistant induction is considered as a promising strategy for protecting crops against extreme high temperature (HT). However, a high-throughput method to accurately estimate the capacity of plant resistance inducers (PRIs) for HT resistance has not been developed. Here, we present a simple approach using fast chlorophyll fluorescence kinetics in <em>Arabidopsis</em> leaf discs to assess PRI efficacy in inducing HT resistance. Both 2-amino-3-methylhexanoic acid (AMHA) and salicylic acid (SA) significantly alleviated the temperature-dependent increase in the K-peak of the OJIP curve and variations in amplitude of heat-responsive JIP-test parameters within the elevated-temperature range of 25–42℃. The PI_ABS (performance index on absorption basis) and W_K (relative variable fluorescence at the K-step to the amplitude F_J - F_O) as two classical heat-responsive characteristic parameters were used to produce a novel hypersensitive parameter HT sensitivity indicator, PI_ABS/W_K (named <em>H</em>_s). Based on the correlation of log<em>H</em>_s with elevated temperatures, a model for quantifying the capacity of HT-resistance induction (called <em>C</em>_<em>i</em>) by AMHA or SA was established. A three-grade classification according to the <em>C</em>_<em>i</em> value was proposed as low (0&lt; <em>C</em>_<em>i</em> ≤ 1℃), moderate (1℃ &lt; <em>C</em>_<em>i</em> ≤ 2℃), and high res_<em>i</em>stance (<em>C</em>_<em>i</em> &gt; 2℃). AMHA at 1 µM and SA at 100 µM had <em>C</em>_<em>i</em> values of 2.49℃ and 4.09℃ in <em>Arabidopsis</em> plants, respectively, associated with their high level of HT resistance induction. Additionally, the EC₅₀ derived from the relative stimulation ratio (<em>K</em>_c) was also introduced as a quantitative index for measuring the ability of AMHA and SA to induce HT resistance. The EC₅₀ value of AMHA is about 0.1 µM in <em>Arabidopsis</em> and 0.35 µM in tomato, being much lower than that of SA (approximately 63 µM in <em>Arabidopsis</em>). Thus, AMHA is a more potent plant inducer than SA. The model was validated through additional experimental evidence, demonstrating its reliability and applicability. This study provides an expeditious high-throughput method for screening promising PRI candidates.</div></div>","PeriodicalId":11758,"journal":{"name":"Environmental and Experimental Botany","volume":"229 ","pages":"Article 106040"},"PeriodicalIF":4.5,"publicationDate":"2024-11-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142745069","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Deciphering genetic mechanisms of Al toxicity tolerance through meta-QTL analysis in rice (Oryza sativa L.)","authors":"Sandeep Jaiswal ,&nbsp;Anita Kumari ,&nbsp;Kuldeep Kumar ,&nbsp;Vijaya Laxmi ,&nbsp;Simardeep Kaur ,&nbsp;Amit Kumar ,&nbsp;Harendra Verma ,&nbsp;Philanim Shimray ,&nbsp;Letngam Touthang ,&nbsp;Manjeet Talukdar ,&nbsp;Vinay Kumar Mishra ,&nbsp;Binay K. Singh","doi":"10.1016/j.envexpbot.2024.106030","DOIUrl":"10.1016/j.envexpbot.2024.106030","url":null,"abstract":"<div><div>Rice is known for its tolerance to high aluminum (Al) concentrations in soil. However, the precise genetic and physiological mechanisms are yet to be fully understood. Recent research has identified several candidate genes (CGs) and quantitative trait loci (QTLs) associated with Al toxicity tolerance in rice. Nevertheless, many more QTLs/genes are yet to be precisely mapped. We employed meta-QTL (M-QTL) analysis, integrating 12 independent mapping studies and 5 Genome-Wide Association Studies (GWAS). The meta-analysis identified 53 M-QTLs from 157 projected QTLs, which were further narrowed down to 28 M-QTLs based on the number of overlapping QTLs on a consensus map. Gene identification through batch retrieval from the RAP database yielded 2765 non-redundant genes within the 28 M-QTL regions. Comparison of M-QTL CGs with six expression datasets associated with Al toxicity tolerance in rice resulted in the identification of 219 CGs with significant differential expression. Notably, 34 CGs were identified to be common across at least 2 studies. Further downstream analyses of CGs revealed the presence of <em>cis</em>-regulatory elements, transcription factors, and transporter proteins related to the Al toxicity tolerance response. Additionally, we analyzed the expression patterns of the four CGs, namely <em>NRT2.3</em>, <em>ALMT4</em>, <em>MT1</em>, and <em>MTP11</em>, which showed significant upregulation in the Al toxicity-tolerant rice genotype, Anjali. Conversely, in the sensitive genotype Swarna, only <em>NRT2.3</em> exhibited upregulation, while <em>ALMT4</em>, <em>MT1</em>, and <em>MTP11</em> were downregulated. Our study highlights significant meta-regions that hold the potential for improving rice genotypes for enhanced tolerance to Al toxicity in acidic soils.</div></div>","PeriodicalId":11758,"journal":{"name":"Environmental and Experimental Botany","volume":"228 ","pages":"Article 106030"},"PeriodicalIF":4.5,"publicationDate":"2024-11-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142654303","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Higher endogenous abscisic acid confers greater tolerance to saline-alkaline stress in Petunia hybrida","authors":"Xueqi Liu ,&nbsp;Hongzhuang Niu ,&nbsp;Jiazhe Li,&nbsp;Decheng Jiang,&nbsp;Ruihong Chen,&nbsp;Rui Zhang,&nbsp;Qian Li","doi":"10.1016/j.envexpbot.2024.106035","DOIUrl":"10.1016/j.envexpbot.2024.106035","url":null,"abstract":"<div><div>Saline-alkaline stress not only leads to reduced crop yields but also diminishes the ornamental value of flowers. While petunia exhibits tolerance to saline-alkaline stress, research on the mechanisms underlying this tolerance remains unreported. We investigated the physiological and molecular mechanisms underlying saline-alkaline stress tolerance using two petunia genotypes (Haishishenlou and Mitchell Diploid) with differing tolerance levels. Haishishenlou exhibited less inhibition of growth under saline-alkaline stress compared to Mitchell Diploid, as indicated by higher biomass. Higher endogenous concentration of abscisic acid (ABA) and greater expression levels of ABA biosynthetic genes and lower expression levels of ABA catabolic genes in Haishishenlou than in Mitchell Diploid were observed when challenged by saline-alkaline stress, suggesting that a higher concentration of ABA may underpin the greater tolerance of Haishishenlou to saline-alkaline stress than that of Mitchell Diploid. Under saline-alkaline conditions, Haishishenlou displayed higher chlorophyll content, photosynthetic rates, Pro and soluble sugars content, as well as higher activities of catalase (CAT), superoxide dismutase (SOD) and peroxidase (POD), and a lower Na⁺/K⁺ ratio. Exogenous application of ABA alleviated the growth inhibition induced by saline-alkaline stress, promoted the accumulation of proline and soluble sugar, reduced reactive oxygen species (ROS) content and Na⁺/K⁺ ratio, and improved antioxidative capacity. These results indicated that a higher endogenous concentration of ABA may underpin the greater tolerance of petunia seedlings to saline-alkaline stress, and exogenous ABA improves the saline-alkaline tolerance of petunia seedlings.</div></div>","PeriodicalId":11758,"journal":{"name":"Environmental and Experimental Botany","volume":"228 ","pages":"Article 106035"},"PeriodicalIF":4.5,"publicationDate":"2024-11-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142657189","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Characterization of two lycopene beta-cyclases reveal their essential roles in photoprotection in Nicotiana tabacum","authors":"Kun Li ,&nbsp;Mengxin Shen ,&nbsp;Ran Wang ,&nbsp;Wenqi Yang ,&nbsp;Lingmin Zou ,&nbsp;Kun-Peng Jia ,&nbsp;Haipeng Li ,&nbsp;Rui Xu ,&nbsp;Qianyun Jia ,&nbsp;Cheng Zhang ,&nbsp;Yujie Wang ,&nbsp;Zhikun Duan ,&nbsp;Xuwu Sun ,&nbsp;Jose R. Botella ,&nbsp;Yuchen Miao ,&nbsp;Jinggong Guo","doi":"10.1016/j.envexpbot.2024.106039","DOIUrl":"10.1016/j.envexpbot.2024.106039","url":null,"abstract":"<div><div>Carotenoids are essential isoprenoids with vital roles in photoprotection and antioxidative processes in photosynthetic organisms. Lycopene Beta-cyclase (<em>β</em>-LCY) is a key enzyme in carotenoid biosynthesis; however, the role of <em>β</em>-LCY in photoprotection is still unclear. In this study, we characterized two <em>β</em>-<em>LCY</em> genes in an allotetraploid tobacco cultivar K326, that are primarily expressed in leaves. Reduction of <em>β-LCY</em> expression by RNA interfercnce (RNAi) resulted in decreased carotenoid content, leaf variegation, impaired photosynthetic efficiency, and abnormal chloroplast morphology. <em>β-LCY</em> RNAi plants exhibited hypersensitivity to high light and lower non-photochemical quenching (NPQ) values under both normal and high light conditions. The stability of D1, a core subunit of photosystem II reaction center, was dramatically impaired <em>β-LCY</em> RNAi plants upon exposure to high light, suggesting severe photodamage of photosystem. Furthermore, reactive oxygen species (ROS) content was increased in <em>β-LCY</em> RNAi plants compared to WT plants under both normal and high light conditions. These results indicate that <em>β</em>-LCY is crucial for NPQ, D1 stability and ROS homeostasis, thus protecting photosystem from photooxidative damage. These findings contribute to our understanding on the function of plant <em>β</em>-LCY and its potential implications for plant growth, development, and photoprotection.</div></div>","PeriodicalId":11758,"journal":{"name":"Environmental and Experimental Botany","volume":"228 ","pages":"Article 106039"},"PeriodicalIF":4.5,"publicationDate":"2024-11-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142700705","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Absorption and partitioning mechanism of nitrogen oxides by typical greening species of tree in Beijing","authors":"Shaowei Lu ,&nbsp;Mengxue Wang ,&nbsp;Jiaxing Fang ,&nbsp;Junjie Zhang ,&nbsp;Xiaotian Xu ,&nbsp;Bin Li ,&nbsp;Qin Zhang ,&nbsp;Chen Liu ,&nbsp;Na Zhao ,&nbsp;Shaoning Li","doi":"10.1016/j.envexpbot.2024.106028","DOIUrl":"10.1016/j.envexpbot.2024.106028","url":null,"abstract":"<div><div>In this study, we analyzed the uptake of nitrogen dioxide (NO₂) and its processes of distribution in various organs of different typical greening species of trees and the differences in its uptake by these different species using the ¹⁵N stable isotope tracer method under the gradient of three NO₂ concentration treatments, namely, low, medium and high. These experiments were conducted using one-time artificial fumigation to provide necessary data and theoretical support for the selection and application of species of greening trees in urban gardens. The treatments of fumigation with different concentrations of NO₂ showed that the leaves of the six species of trees had the highest content of ¹⁵N. The organs that were the most effective at taking up ¹⁵N were the leaves in broadleaf trees and the branches in conifers. The content of ¹⁵N per unit of the leaves (0.0058–2.0486 μg/g) increased in parallel with the concentration of fumigant and then was rapidly transported to various organs in the tree. This caused different degrees of changes in other organs. The total content of ¹⁵N per unit was higher in the broadleaf species (0.0129–2.3171 μg/g) than in the conifers (0.0296–0.1260 μg/g). The leaves of broadleaf trees were the most effective at taking up ¹⁵N (0.0054–1.3228 %) under medium and high concentrations of fumigant with the exception of ginkgo. The ability of each organ of the other broadleaf species was leaves&gt;branches&gt;trunks&gt;roots, and the branches of conifers were the most effective parts of the trees at taking up NO₂ under three concentrations of fumigants (0.0789–0.4005 %). The highest rate of distribution of ¹⁵N was found in the leaves (48.14–99.53 %) in all six species under different concentrations of fumigant, and the distribution in the other organs varied to different degrees.</div></div>","PeriodicalId":11758,"journal":{"name":"Environmental and Experimental Botany","volume":"228 ","pages":"Article 106028"},"PeriodicalIF":4.5,"publicationDate":"2024-11-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142654335","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Nitrogen regulated reactive oxygen species metabolism of leaf and grain under elevated temperature during the grain-filling stage to stabilize rice substance accumulation","authors":"Yufei Zhao ,&nbsp;Yigong Zhao ,&nbsp;Yuxuan Peng ,&nbsp;Yiqian Sun ,&nbsp;Dengying Zhang ,&nbsp;Chen Zhang ,&nbsp;Xuan Ran ,&nbsp;Yingying Shen ,&nbsp;Wenzhe Liu ,&nbsp;Yanfeng Ding ,&nbsp;She Tang","doi":"10.1016/j.envexpbot.2024.106037","DOIUrl":"10.1016/j.envexpbot.2024.106037","url":null,"abstract":"<div><div>Rational additional nitrogen is an important agronomic measure to cope with the adverse effects of warming on rice production. However, the mechanism by which nitrogen mitigated the adverse impact of substance accumulation due to elevated temperature is poorly clarified. Therefore, in this study, a field warming experiment during grain filling and 60 kg·ha⁻¹ of additional nitrogen was established. Under elevated temperature, panicle temperature was higher and increased more substantially than leaf temperature. However, nitrogen application did not significantly reduce the leaf, panicle, and canopy temperatures. Additional nitrogen under elevated temperature delayed the decline of chlorophyll, maintained leaf photosynthesis, and prolonged grain-filling period to alleviate the decrease of starch due to warming. Hydrogen peroxide (H₂O₂) was sensitive to elevated temperature in leaves and grains. However, application of nitrogen under elevated temperature improved the activity of antioxidant enzymes to mitigate the increase of H₂O₂, resulting in a 30.31 % and 45.33 % decrease of H₂O₂ in leaves and grains compared to elevated temperature, respectively. Elevated temperature promoted the expression of heat-responsive genes, especially <em>HSP16.9</em> and <em>HSP26.7</em>, which were consistently increased in response to warming at 5–30d after flowering. In addition, the expression of <em>HSP16.9</em> at 5d and 10d after flowering and <em>HSP26.7</em> at 10d after flowering was further increased with nitrogen application under elevated temperature. Therefore, HSP may be the key regulator of grain response to warming with additional nitrogen under elevated temperature. In conclusion, the relevant results revealed the physiological mechanism of nitrogen to guarantee substance accumulation and provided new ideas for cultivation measures to protect against the likely scenario of global warming.</div></div>","PeriodicalId":11758,"journal":{"name":"Environmental and Experimental Botany","volume":"229 ","pages":"Article 106037"},"PeriodicalIF":4.5,"publicationDate":"2024-11-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142745068","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Foliar flavonoids across an elevation gradient: Plasticity in response to UV, and links with floral pigmentation patterning","authors":"Matthew H. Koski ,&nbsp;Elizabeth Leonard ,&nbsp;Nishanth Tharayil","doi":"10.1016/j.envexpbot.2024.106036","DOIUrl":"10.1016/j.envexpbot.2024.106036","url":null,"abstract":"<div><div>Metabolites produced in the flavonoid biosynthetic pathway (FBP) mitigate abiotic stress caused by factors such as ultraviolet (UV) light. Testing whether constitutive flavonoid production or flavonoid plasticity differ between populations spanning ecological gradients can reveal whether geographic patterns are consistent with local adaptation. Abiotic induction of flavonoids can occur in leaves as well as flowers where flavonoids influence UV color patterns perceived by pollinators. Assessing how foliar flavonoids are associated with floral color phenotypes can shed light on how pleiotropy affects biochemical phenotypes across tissues. We exposed <em>Argentina anserina</em> (Rosaceae) plants from alpine and lower elevation populations to low and high levels of UV and measured foliar and petal flavonoid production using UHPLC coupled mass spectrometry. We associated foliar flavonoid abundance with petal flavonoid abundance, and the size of the UV absorbing petal area (‘UV bullseye’). We found that total foliar flavonoids increased in response to UV due to flavonol upregulation, but only one class of flavonols, fisetin, exhibited stronger plasticity in alpine populations. Alpine populations tended to increase the quercetin-kaempferol ratio more than low elevation populations when exposed to higher UV, a signature of photoprotection and radical scavenging. Relationships between foliar flavonoids and the floral UV bullseye differed between alpine and low elevation populations. Previous work showed kaempferol glycosides contributed to variation in UV bullseye size at high elevation, while non-kaempferols spanning multiple FBP branches were associated with bullseye size at low elevation. Here, we found that alpine plants with less foliar kaempferol and greater kaempferol allocation to petals than leaves had larger floral UV-bullseyes, suggesting that floral UV patterning may be shaped by a biochemical tradeoff between tissues. Overall, nuanced elevational differences in flavonoid plasticity revealed by detailed metabolite classification provided support for local adaptation. Additionally, our study highlights that flavonoid production in leaves could influence the evolution of flavonoid-based floral phenotypes.</div></div>","PeriodicalId":11758,"journal":{"name":"Environmental and Experimental Botany","volume":"228 ","pages":"Article 106036"},"PeriodicalIF":4.5,"publicationDate":"2024-11-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142654299","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}