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2 pages, 185 KiB

Open AccessEditorial

Crop Adaptation to Elevated CO₂ and Temperature

by James Bunce

Plants 2022, 11(3), 453; https://doi.org/10.3390/plants11030453 - 7 Feb 2022

Cited by 1 | Viewed by 1693

Abstract

There is no ambiguity about the fact that both atmospheric CO₂ levels and air temperatures are continuing to increase [...] Full article

(This article belongs to the Special Issue Crop Adaptation to Elevated CO₂ and Temperature)

Research

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12 pages, 12585 KiB

Open AccessEditor’s ChoiceArticle

Effects of Elevated Temperature on Root System Development of Two Lupine Species

by Virgilija Gavelienė, Sigita Jurkonienė, Elžbieta Jankovska-Bortkevič and Danguolė Švegždienė

Plants 2022, 11(2), 192; https://doi.org/10.3390/plants11020192 - 12 Jan 2022

Cited by 13 | Viewed by 2529

Abstract

The aim of this study was to assess the effect of elevated temperature on the growth, morphology and spatial orientation of lupine roots at the initial stages of development and on the formation of lupine root architecture at later stages. Two lupine species [...] Read more.

The aim of this study was to assess the effect of elevated temperature on the growth, morphology and spatial orientation of lupine roots at the initial stages of development and on the formation of lupine root architecture at later stages. Two lupine species were studied—the invasive Lupinus polyphyllus Lindl. and the non-invasive L. luteus L. The plants were grown in climate chambers under 25 °C and simulated warming at 30 °C conditions. The angle of root curvature towards the vector of gravity was measured at the 48th hour of growth, and during a 4-h period after 90° reorientation. Root biometrical, histological measurements were carried out on 7-day-old and 30-day-old plants. The elevation of 5 °C affected root formation of the two lupine species differently. The initial roots of L. polyphyllus were characterized by worse spatial orientation, reduced growth and reduced mitotic index of root apical meristem at 30 °C compared with 25 °C. The length of primary roots of 30-day-old lupines and the number of lateral roots decreased by 14% and 16%, respectively. More intense root development and formation were observed in non-invasive L. luteus at 30 °C. Our results provide important information on the effect of elevated temperature on the formation of root architecture in two lupine species and suggest that global warming may impact the invasiveness of these species. Full article

(This article belongs to the Special Issue Crop Adaptation to Elevated CO₂ and Temperature)

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14 pages, 2572 KiB

Open AccessArticle

Impacts of Carbon Dioxide Enrichment on Landrace and Released Ethiopian Barley (Hordeum vulgare L.) Cultivars

by Mekides Woldegiorgis Gardi, Waqas Ahmed Malik and Bettina I. G. Haussmann

Plants 2021, 10(12), 2691; https://doi.org/10.3390/plants10122691 - 7 Dec 2021

Cited by 3 | Viewed by 2458

Abstract

Barley (Hordeum vulgare L.) is an important food security crop due to its high-stress tolerance. This study explored the effects of CO₂ enrichment (eCO₂) on the growth, yield, and water-use efficiency of Ethiopian barley cultivars (15 landraces, 15 released). [...] Read more.

Barley (Hordeum vulgare L.) is an important food security crop due to its high-stress tolerance. This study explored the effects of CO₂ enrichment (eCO₂) on the growth, yield, and water-use efficiency of Ethiopian barley cultivars (15 landraces, 15 released). Cultivars were grown under two levels of CO₂ concentration (400 and 550 ppm) in climate chambers, and each level was replicated three times. A significant positive effect of eCO₂ enrichment was observed on plant height by 9.5 and 6.7%, vegetative biomass by 7.6 and 9.4%, and grain yield by 34.1 and 40.6% in landraces and released cultivars, respectively. The observed increment of grain yield mainly resulted from the significant positive effect of eCO₂ on grain number per plant. The water-use efficiency of vegetative biomass and grain yield significantly increased by 7.9 and 33.3% in landraces, with 9.5 and 42.9% improvement in released cultivars, respectively. Pearson’s correlation analysis revealed positive relationships between grain yield and grain number (r = 0.95), harvest index (r = 0.86), and ear biomass (r = 0.85). The response of barley to eCO₂ was cultivar dependent, i.e., the highest grain yield response to eCO₂ was observed for Lan_15 (122.3%) and Rel_10 (140.2%). However, Lan_13, Land_14, and Rel_3 showed reduced grain yield by 16, 25, and 42%, respectively, in response to eCO₂ enrichment. While the released cultivars benefited more from higher levels of CO₂ in relative terms, some landraces displayed better actual values. Under future climate conditions, i.e., future CO₂ concentrations, grain yield production could benefit from the promotion of landrace and released cultivars with higher grain numbers and higher levels of water-use efficiency of the grain. The superior cultivars that were identified in the present study represent valuable genetic resources for future barley breeding. Full article

(This article belongs to the Special Issue Crop Adaptation to Elevated CO₂ and Temperature)

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19 pages, 8621 KiB

Open AccessArticle

Screening for Higher Grain Yield and Biomass among Sixty Bread Wheat Genotypes Grown under Elevated CO₂ and High-Temperature Conditions

by Emilio L. Marcos-Barbero, Pilar Pérez, Rafael Martínez-Carrasco, Juan B. Arellano and Rosa Morcuende

Plants 2021, 10(8), 1596; https://doi.org/10.3390/plants10081596 - 3 Aug 2021

Cited by 14 | Viewed by 4176

Abstract

Global warming will inevitably affect crop development and productivity, increasing uncertainty regarding food production. The exploitation of genotypic variability can be a promising approach for selecting improved crop varieties that can counteract the adverse effects of future climate change. We investigated the natural [...] Read more.

Global warming will inevitably affect crop development and productivity, increasing uncertainty regarding food production. The exploitation of genotypic variability can be a promising approach for selecting improved crop varieties that can counteract the adverse effects of future climate change. We investigated the natural variation in yield performance under combined elevated CO₂ and high-temperature conditions in a set of 60 bread wheat genotypes (59 of the 8TH HTWSN CIMMYT collection and Gazul). Plant height, biomass production, yield components and phenological traits were assessed. Large variations in the selected traits were observed across genotypes. The CIMMYT genotypes showed higher biomass and grain yield when compared to Gazul, indicating that the former performed better than the latter under the studied environmental conditions. Principal component and hierarchical clustering analyses revealed that the 60 wheat genotypes employed different strategies to achieve final grain yield, highlighting that the genotypes that can preferentially increase grain and ear numbers per plant will display better yield responses under combined elevated levels of CO₂ and temperature. This study demonstrates the success of the breeding programs under warmer temperatures and the plants’ capacity to respond to the concurrence of certain environmental factors, opening new opportunities for the selection of widely adapted climate-resilient wheat genotypes. Full article

(This article belongs to the Special Issue Crop Adaptation to Elevated CO₂ and Temperature)

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13 pages, 1727 KiB

Open AccessFeature PaperArticle

Elevated Temperature Induced Adaptive Responses of Two Lupine Species at Early Seedling Phase

by Sigita Jurkonienė, Jurga Jankauskienė, Rima Mockevičiūtė, Virgilija Gavelienė, Elžbieta Jankovska-Bortkevič, Iskren Sergiev, Dessislava Todorova and Nijolė Anisimovienė

Plants 2021, 10(6), 1091; https://doi.org/10.3390/plants10061091 - 29 May 2021

Cited by 3 | Viewed by 2552

Abstract

This study aimed to investigate the impact of climate warming on hormonal traits of invasive and non-invasive plants at the early developmental stage. Two different lupine species—invasive Lupinus polyphyllus Lindl. and non-invasive Lupinus luteus L.—were used in this study. Plants were grown in [...] Read more.

This study aimed to investigate the impact of climate warming on hormonal traits of invasive and non-invasive plants at the early developmental stage. Two different lupine species—invasive Lupinus polyphyllus Lindl. and non-invasive Lupinus luteus L.—were used in this study. Plants were grown in climate chambers under optimal (25 °C) and simulated climate warming conditions (30 °C). The content of phytohormone indole-3-acetic acid (IAA), ethylene production and the adaptive growth of both species were studied in four-day-old seedlings. A higher content of total IAA, especially of IAA-amides and transportable IAA, as well as higher ethylene emission, was determined to be characteristic for invasive lupine both under optimal and simulated warming conditions. It should be noted that IAA-L-alanine was detected entirely in the invasive plants under both growth temperatures. Further, the ethylene emission values increased significantly in invasive lupine hypocotyls under 30 °C. Invasive plants showed plasticity in their response by reducing growth in a timely manner and adapting to the rise in temperature. Based on the data of the current study, it can be suggested that the invasiveness of both species may be altered under climate warming conditions. Full article

(This article belongs to the Special Issue Crop Adaptation to Elevated CO₂ and Temperature)

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16 pages, 1340 KiB

Open AccessEditor’s ChoiceArticle

Yield, Physiological Performance, and Phytochemistry of Basil (Ocimum basilicum L.) under Temperature Stress and Elevated CO₂ Concentrations

by T. Casey Barickman, Omolayo J. Olorunwa, Akanksha Sehgal, C. Hunt Walne, K. Raja Reddy and Wei Gao

Plants 2021, 10(6), 1072; https://doi.org/10.3390/plants10061072 - 27 May 2021

Cited by 20 | Viewed by 6237

Abstract

Early season sowing is one of the methods for avoiding yield loss for basil due to high temperatures. However, basil could be exposed to sub-optimal temperatures by planting it earlier in the season. Thus, an experiment was conducted that examines how temperature changes [...] Read more.

Early season sowing is one of the methods for avoiding yield loss for basil due to high temperatures. However, basil could be exposed to sub-optimal temperatures by planting it earlier in the season. Thus, an experiment was conducted that examines how temperature changes and carbon dioxide (CO₂) levels affect basil growth, development, and phytonutrient concentrations in a controlled environment. The experiment simulated temperature stress, low (20/12 °C), and high (38/30 °C), under ambient (420 ppm) and elevated (720 ppm) CO₂ concentrations. Low-temperature stress prompted the rapid closure of stomata resulting in a 21% decline in net photosynthesis. Chlorophylls and carotenoids decreased when elevated CO₂ interacted with low-temperature stress. Basil exhibited an increase in stomatal conductance, intercellular CO₂ concentration, apparent quantum yield, maximum photosystem II efficiency, and maximum net photosynthesis rate when subjected to high-temperature stress. Under elevated CO₂, increasing the growth temperature from 30/22 °C to 38/30 °C markedly increased the antioxidants content of basil. Taken together, the evidence from this research recommends that varying the growth temperature of basil plants can significantly affect the growth and development rates compared to increasing the CO₂ concentrations, which mitigates the adverse effects of temperature stress. Full article

(This article belongs to the Special Issue Crop Adaptation to Elevated CO₂ and Temperature)

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19 pages, 1722 KiB

Open AccessArticle

Climate Change, Crop Yields, and Grain Quality of C₃ Cereals: A Meta-Analysis of [CO₂], Temperature, and Drought Effects

by Sinda Ben Mariem, David Soba, Bangwei Zhou, Irakli Loladze, Fermín Morales and Iker Aranjuelo

Plants 2021, 10(6), 1052; https://doi.org/10.3390/plants10061052 - 24 May 2021

Cited by 60 | Viewed by 8764

Abstract

Cereal yield and grain quality may be impaired by environmental factors associated with climate change. Major factors, including elevated CO₂ concentration ([CO₂]), elevated temperature, and drought stress, have been identified as affecting C₃ crop production and quality. A meta-analysis [...] Read more.

Cereal yield and grain quality may be impaired by environmental factors associated with climate change. Major factors, including elevated CO₂ concentration ([CO₂]), elevated temperature, and drought stress, have been identified as affecting C₃ crop production and quality. A meta-analysis of existing literature was performed to study the impact of these three environmental factors on the yield and nutritional traits of C₃ cereals. Elevated [CO₂] stimulates grain production (through larger grain numbers) and starch accumulation but negatively affects nutritional traits such as protein and mineral content. In contrast to [CO₂], increased temperature and drought cause significant grain yield loss, with stronger effects observed from the latter. Elevated temperature decreases grain yield by decreasing the thousand grain weight (TGW). Nutritional quality is also negatively influenced by the changing climate, which will impact human health. Similar to drought, heat stress decreases starch content but increases grain protein and mineral concentrations. Despite the positive effect of elevated [CO₂], increases to grain yield seem to be counterbalanced by heat and drought stress. Regarding grain nutritional value and within the three environmental factors, the increase in [CO₂] is possibly the more detrimental to face because it will affect cereal quality independently of the region. Full article

(This article belongs to the Special Issue Crop Adaptation to Elevated CO₂ and Temperature)

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15 pages, 3069 KiB

Open AccessArticle

Role of Tuber Developmental Processes in Response of Potato to High Temperature and Elevated CO₂

by Chien-Teh Chen and Tim L. Setter

Plants 2021, 10(5), 871; https://doi.org/10.3390/plants10050871 - 26 Apr 2021

Cited by 13 | Viewed by 3145

Abstract

Potato is adapted to cool environments, and there is concern that its performance may be diminished considerably due to global warming and more frequent episodes of heat stress. Our objectives were to determine the response of potato plants to elevated CO₂ (700 [...] Read more.

Potato is adapted to cool environments, and there is concern that its performance may be diminished considerably due to global warming and more frequent episodes of heat stress. Our objectives were to determine the response of potato plants to elevated CO₂ (700 μmol/mol) and high temperature (35/25 °C) at tuber initiation and tuber bulking, and to elucidate effects on sink developmental processes. Potato plants were grown in controlled environments with treatments at: Tuber initiation (TI), during the first two weeks after initiating short-day photoperiods, and Tuber bulking (TB). At TI, and 25 °C, elevated CO₂ increased tuber growth rate, while leaves and stems were not affected. Whole-plant dry matter accumulation rate, was inhibited by high temperature about twice as much at TI than at TB. Elevated CO₂ partially ameliorated high temperature inhibition of sink organs. At TI, with 25 °C, elevated CO₂ primarily affected tuber cell proliferation. In contrast, tuber cell volume and endoreduplication were unaffected. These findings indicate that the TI stage and cell division is particularly responsive to elevated CO₂ and high temperature stress, supporting the view that attention should be paid to the timing of high-temperature stress episodes with respect to this stage. Full article

(This article belongs to the Special Issue Crop Adaptation to Elevated CO₂ and Temperature)

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18 pages, 1905 KiB

Open AccessArticle

Elevated Carbon Dioxide and Chronic Warming Together Decrease Nitrogen Uptake Rate, Net Translocation, and Assimilation in Tomato

by Dileepa M. Jayawardena, Scott A. Heckathorn, Krishani K. Rajanayake, Jennifer K. Boldt and Dragan Isailovic

Plants 2021, 10(4), 722; https://doi.org/10.3390/plants10040722 - 8 Apr 2021

Cited by 4 | Viewed by 2723

Abstract

The response of plant N relations to the combination of elevated CO₂ (eCO₂) and warming are poorly understood. To study this, tomato (Solanum lycopersicum) plants were grown at 400 or 700 ppm CO₂ and 33/28 or 38/33 [...] Read more.

The response of plant N relations to the combination of elevated CO₂ (eCO₂) and warming are poorly understood. To study this, tomato (Solanum lycopersicum) plants were grown at 400 or 700 ppm CO₂ and 33/28 or 38/33 °C (day/night), and their soil was labeled with ¹⁵NO₃⁻ or ¹⁵NH₄⁺. Plant dry mass, root N-uptake rate, root-to-shoot net N translocation, whole-plant N assimilation, and root resource availability (%C, %N, total nonstructural carbohydrates) were measured. Relative to eCO₂ or warming alone, eCO₂ + warming decreased growth, NO₃⁻ and NH₄⁺-uptake rates, root-to-shoot net N translocation, and whole-plant N assimilation. Decreased N assimilation with eCO₂ + warming was driven mostly by inhibition of NO₃⁻ assimilation, and was not associated with root resource limitations or damage to N-assimilatory proteins. Previously, we showed in tomato that eCO₂ + warming decreases the concentration of N-uptake and -assimilatory proteins in roots, and dramatically increases leaf angle, which decreases whole-plant light capture and, hence, photosynthesis and growth. Thus, decreases in N uptake and assimilation with eCO₂ + warming in tomato are likely due to reduced plant N demand. Full article

(This article belongs to the Special Issue Crop Adaptation to Elevated CO₂ and Temperature)

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12 pages, 827 KiB

Open AccessArticle

Does Elevated [CO₂] Only Increase Root Growth in the Topsoil? A FACE Study with Lentil in a Semi-Arid Environment

by Maryse Bourgault, Sabine Tausz-Posch, Mark Greenwood, Markus Löw, Samuel Henty, Roger D. Armstrong, Garry L. O’Leary, Glenn J. Fitzgerald and Michael Tausz

Plants 2021, 10(4), 612; https://doi.org/10.3390/plants10040612 - 24 Mar 2021

Cited by 3 | Viewed by 2317

Abstract

Atmospheric carbon dioxide concentrations [CO₂] are increasing steadily. Some reports have shown that root growth in grain crops is mostly stimulated in the topsoil rather than evenly throughout the soil profile by e[CO₂], which is not optimal for crops [...] Read more.

Atmospheric carbon dioxide concentrations [CO₂] are increasing steadily. Some reports have shown that root growth in grain crops is mostly stimulated in the topsoil rather than evenly throughout the soil profile by e[CO₂], which is not optimal for crops grown in semi-arid environments with strong reliance on stored water. An experiment was conducted during the 2014 and 2015 growing seasons with two lentil (Lens culinaris) genotypes grown under Free Air CO₂ Enrichment (FACE) in which root growth was observed non-destructively with mini-rhizotrons approximately every 2–3 weeks. Root growth was not always statistically increased by e[CO₂] and not consistently between depths and genotypes. In 2014, root growth in the top 15 cm of the soil profile (topsoil) was indeed increased by e[CO₂], but increases at lower depths (30–45 cm) later in the season were greater than in the topsoil. In 2015, e[CO₂] only increased root length in the topsoil for one genotype, potentially reflecting the lack of plant available soil water between 30–60 cm until recharged by irrigation during grain filling. Our limited data to compare responses to e[CO₂] showed that root length increases in the topsoil were correlated with a lower yield response to e[CO₂]. The increase in yield response was rather correlated with increases in root growth below 30 cm depth. Full article

(This article belongs to the Special Issue Crop Adaptation to Elevated CO₂ and Temperature)

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15 pages, 3262 KiB

Open AccessFeature PaperArticle

Cloning and Characterization of Three Sugar Metabolism Genes (LBGAE, LBGALA, and LBMS) Regulated in Response to Elevated CO₂ in Goji Berry (Lycium barbarum L.)

by Yaping Ma, Mura Jyostna Devi, Vangimalla R. Reddy, Lihua Song, Handong Gao and Bing Cao

Plants 2021, 10(2), 321; https://doi.org/10.3390/plants10020321 - 7 Feb 2021

Cited by 9 | Viewed by 2772

Abstract

The composition and content of sugar play a pivotal role in goji berry (Lycium barbarum L.) fruits, determining fruit quality. Long-term exposure of goji berry to elevated CO₂ (eCO₂) was frequently demonstrated to reduce sugar content and secondary metabolites. [...] Read more.

The composition and content of sugar play a pivotal role in goji berry (Lycium barbarum L.) fruits, determining fruit quality. Long-term exposure of goji berry to elevated CO₂ (eCO₂) was frequently demonstrated to reduce sugar content and secondary metabolites. In order to understand the regulatory mechanisms and improve the quality of fruit in the changing climate, it is essential to characterize sugar metabolism genes that respond to eCO₂. The objectives of this study were to clone full-length cDNA of three sugar metabolism genes—LBGAE (Lycium barbarum UDP-glucuronate 4-epimerase), LBGALA (Lycium barbarum alpha-galactosidase), and LBMS (Lycium barbarum malate synthase)—that were previously identified responding to eCO₂, and to analyze sequence characteristics and expression regulation patterns. Sugar metabolism enzymes regulated by these genes were also estimated along with various carbohydrates from goji berry fruits grown under ambient (400 μmol mol⁻¹) and elevated (700 μmol mol⁻¹) CO₂ for 90 and 120 days. Homology-based sequence analysis revealed that the protein-contained functional domains are similar to sugar transport regulation and had a high sequence homology with other Solanaceae species. The sucrose metabolism-related enzyme’s activity varied significantly from ambient to eCO₂ in 90-day and 120-day samples along with sugars. This study provides fundamental information on sugar metabolism genes to eCO₂ in goji berry to enhance fruit quality to climate change. Full article

(This article belongs to the Special Issue Crop Adaptation to Elevated CO₂ and Temperature)

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Review

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14 pages, 510 KiB

Open AccessFeature PaperEditor’s ChoiceReview

Effects of Elevated CO₂ and Heat on Wheat Grain Quality

by Xizi Wang and Fulai Liu

Plants 2021, 10(5), 1027; https://doi.org/10.3390/plants10051027 - 20 May 2021

Cited by 43 | Viewed by 7910

Abstract

Wheat is one of the most important staple foods in temperate regions and is in increasing demand in urbanizing and industrializing countries such as China. Enhancing yield potential to meet the population explosion around the world and maintaining grain quality in wheat plants [...] Read more.

Wheat is one of the most important staple foods in temperate regions and is in increasing demand in urbanizing and industrializing countries such as China. Enhancing yield potential to meet the population explosion around the world and maintaining grain quality in wheat plants under climate change are crucial for food security and human nutrition. Global warming resulting from greenhouse effect has led to more frequent occurrence of extreme climatic events. Elevated atmospheric CO₂ concentration (eCO₂) along with rising temperature has a huge impact on ecosystems, agriculture and human health. There are numerous studies investigating the eCO₂ and heatwaves effects on wheat growth and productivity, and the mechanisms behind. This review outlines the state-of-the-art knowledge regarding the effects of eCO₂ and heat stress, individually and combined, on grain yield and grain quality in wheat crop. Strategies to enhance the resilience of wheat to future warmer and CO₂-enriched environment are discussed. Full article

(This article belongs to the Special Issue Crop Adaptation to Elevated CO₂ and Temperature)

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9 pages, 514 KiB

Open AccessReview

Crop Adaptation: Weedy and Crop Wild Relatives as an Untapped Resource to Utilize Recent Increases in Atmospheric CO₂

by Lewis H. Ziska

Plants 2021, 10(1), 88; https://doi.org/10.3390/plants10010088 - 4 Jan 2021

Cited by 4 | Viewed by 2788

Abstract

Adaptation measures are necessary to ensure the stability and performance of the food supply relative to anthropogenic climate change. Although a wide range of measures have been proposed (e.g., planting dates, crop choices, drought resistance), there may be a ubiquitous means to increase [...] Read more.

Adaptation measures are necessary to ensure the stability and performance of the food supply relative to anthropogenic climate change. Although a wide range of measures have been proposed (e.g., planting dates, crop choices, drought resistance), there may be a ubiquitous means to increase productivity relatively quickly. Numerous studies have shown that the projected increase in atmospheric CO₂ can stimulate crop growth and seed yield with noted intra-specific differences within crop cultivars, suggesting potential differences to CO₂ that could be exploited to enhance seed yield in the future. However, it is worth emphasizing that atmospheric CO₂ has already risen substantially (≈27% since 1970) and that, at present, no active effort by breeders has been made to select for the CO₂ increase that has already occurred. In contrast, for weedy or crop wild relatives (CWR), there are indications of evolutionary adaptation to these recent increases. While additional steps are needed, the identification and introgression of these CO₂-sensitive traits into modern crop cultivars may be a simple and direct means to increase crop growth and seed yield. Full article

(This article belongs to the Special Issue Crop Adaptation to Elevated CO₂ and Temperature)

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