Search for Articles:
Title / Keyword
Author / Affiliation / Email
Journal
Article Type
 
 
Advanced Search
 
Section
Special Issue
Volume
Issue
Number
Page
 
5.2
3.7
Journals
Agronomy
Special Issues
Resilience to Biotic and Environmental Stresses in Horticultural Crops
share announcement

Resilience to Biotic and Environmental Stresses in Horticultural Crops

A special issue of Agronomy (ISSN 2073-4395). This special issue belongs to the section "Horticultural and Floricultural Crops".

Deadline for manuscript submissions: closed (31 January 2023) | Viewed by 26238

Special Issue Editors

Dr. Muhammad Shahid

E-Mail Website
Guest Editor
Department of Agriculture, Nutrition and Food Systems, University of New Hampshire, Durham, NH 03824, USA
Interests: abiotic stresses (salinity; drought; heat; heavy metal toxicity); biochar as soilless media amendment; stress physiology; ecophysiology plant nutrients
Special Issues, Collections and Topics in MDPI journals
Dr. Ali Sarkhosh

E-Mail Website
Guest Editor
Horticultural Sciences Department, University of Florida, Gainesville, FL 32611, USA
Interests: tree fruit production; nutrient management in tree fruit and grapes; rootstock and scion evaluation; cultural practices to optimize fruit size

Special Issue Information

Dear Colleagues，

Environmental stresses limit crop productivity and are a major constraint on global food security for the ever-growing population. As a consequence of global climate change, abiotic stresses (such as salinity, drought, heat, cold, heavy metal toxicity, ozone, and UV radiation), and botic agents (weeds, diseases, and insect-pests) will be more prevalent in the coming years. Abiotic and biotic stresses cause various kinds of morphological, physiological, biochemical, and genomic modulations, resulting in a reduction in plant growth, productivity, and produce quality in horticultural crops (fruits, vegetables, hers, and ornamentals).

Therefore, plant physiologists, horticulturists, entomologist, plant pathalogist, agronomists, plant breeders, food technologists, and economists are working together to tackel the deleterious effects of abiotic stresses in horticultural crops. Scientist throughout the world are working on different aspects and strategies, such as nutrient management, soil amendments, breeding for tolerant varieties, stress inducers, crop modelling and remote sensing, biostimulants and biopesticides, nano fertilizers, unmaned aerial vehicles (UAV), high throughput phenotyping, and many more, in order to understand stress tolerance mechanisms and their alleviation.

Thus, in this Special Issue, we aim to publish research articles and reviews on various strategies effective in improving horticultural crops resilience to biotic and environmental stresses. This Special Issue will serve as a foundation for the sustainable production of horticultural crops in a climate change scenario.

Dr. Muhammad Adnan Shahid
Dr. Ali Sarkhosh
Guest Editors

Manuscript Submission Information

Manuscripts should be submitted online at www.mdpi.com by registering and logging in to this website. Once you are registered, click here to go to the submission form. Manuscripts can be submitted until the deadline. All submissions that pass pre-check are peer-reviewed. Accepted papers will be published continuously in the journal (as soon as accepted) and will be listed together on the special issue website. Research articles, review articles as well as short communications are invited. For planned papers, a title and short abstract (about 100 words) can be sent to the Editorial Office for announcement on this website.

Submitted manuscripts should not have been published previously, nor be under consideration for publication elsewhere (except conference proceedings papers). All manuscripts are thoroughly refereed through a single-blind peer-review process. A guide for authors and other relevant information for submission of manuscripts is available on the Instructions for Authors page. Agronomy is an international peer-reviewed open access monthly journal published by MDPI.

Please visit the Instructions for Authors page before submitting a manuscript. The Article Processing Charge (APC) for publication in this open access journal is 2600 CHF (Swiss Francs). Submitted papers should be well formatted and use good English. Authors may use MDPI's English editing service prior to publication or during author revisions.

Keywords

  • environmental stresses
  • high-throughput phenotyping
  • plant resilience
  • diseases and pathogens
  • weed management
  • nutrient and water mangement
  • soil amendments
  • soilless and hydroponics
  • remote sensing
  • breeding

Published Papers (11 papers)

Download All Papers
Order results
Result details
Show export options expand_more Show export options expand_less
Select all
Export citation of selected articles as:

Research

19 pages, 1113 KiB  
Article
The Effect of Water Stress on the Glucosinolate Content and Profile: A Comparative Study on Roots and Leaves of Brassica oleracea L. Crops
by Hajer Ben Ammar, Donata Arena, Simone Treccarichi, Maria Concetta Di Bella, Sonia Marghali, Nadia Ficcadenti, Roberto Lo Scalzo and Ferdinando Branca
Agronomy 2023, 13(2), 579; https://doi.org/10.3390/agronomy13020579 - 17 Feb 2023
Cited by 14 | Viewed by 2030
Abstract
Drought is one of the major challenges of global crop production, and its severity is increasing because of climate change. This abiotic stress is an important target for Brassica species, which are generally grown in arid and semi-arid climates. This study was conducted [...] Read more.
Drought is one of the major challenges of global crop production, and its severity is increasing because of climate change. This abiotic stress is an important target for Brassica species, which are generally grown in arid and semi-arid climates. This study was conducted to investigate the effects of water deficit on a set of accessions belonging to the Brassica core collection of the EU H2020 BRESOV project, represented by Brassica oleracea L. crops and Brassica oleracea complex species (n = 9). In particular, the variation in the amount and profile of the glucosinolates (GLSs) compounds was analyzed on the root and the leaf tissues. The plant morphometric traits and GLSs amount and profile were detected for the plants grown in cold greenhouse in Catania (Sicily) during the autumn–winter season for ten weeks. The results showed a wide qualitative and quantitative variation among the Brassica accessions. The GLSs profile varied qualitatively and quantitively among both genotypes and portions of the plants (hypogenous-root and epigeous-leaf). Plants grown under drought stress, for the last two weeks of the growing cycle under consideration, showed a higher amount of GLS in their leaves (190.1 ± 8.9 µmol. g−1 d.w.) compared to their roots (17.3 ± 1.9 µmol. g−1 d.w.). Under water stress conditions, the highest increase in the glucosinolate amount was detected in broccoli (the accession BR1) with 85.4% and in cauliflower (the accession CV1) with 72.8% in the roots and leaves, respectively. Positive correlations were found between the major leaf and root GLSs identified. The selection of chemotypes allows for an important time reduction during the breeding programs after crossing accessions with the specific profiles of glucosinolates. Full article
(This article belongs to the Special Issue Resilience to Biotic and Environmental Stresses in Horticultural Crops)
►▼ Show Figures

Figure 1

16 pages, 4012 KiB  
Article
Foliar Applications of ZnO and SiO2 Nanoparticles Mitigate Water Deficit and Enhance Potato Yield and Quality Traits
by Mahmoud F. Seleiman, Wadei A. Al-Selwey, Abdullah A. Ibrahim, Mohamed Shady and Abdullah A. Alsadon
Agronomy 2023, 13(2), 466; https://doi.org/10.3390/agronomy13020466 - 04 Feb 2023
Cited by 26 | Viewed by 2258
Abstract
The yield and quality of field crops are affected by abiotic stresses such as water deficit, which can negatively impact crop growth, productivity, and quality. However, nanotechnology holds great promise for increasing crop yield, maintaining quality, and thus mitigating abiotic stresses. Therefore, the [...] Read more.
The yield and quality of field crops are affected by abiotic stresses such as water deficit, which can negatively impact crop growth, productivity, and quality. However, nanotechnology holds great promise for increasing crop yield, maintaining quality, and thus mitigating abiotic stresses. Therefore, the current study was conducted to examine the influences of 0, 50, and 100 mg L−1 zinc oxide (ZnO) nanoparticles and 0, 25, and 50 mg L−1 silicon dioxide (SiO2) nanoparticles on the yield and quality traits of potato plants grown under water deficit conditions (100%, 75%, and 50% ETc). Water deficit significantly reduced yield traits (average tuber weight, number of plant tubers, and tuber yield) and quality traits (tuber diameter, crude protein, and mineral content). However, it enhanced tuber dry weight, specific gravity, ascorbic acid, starch, and total soluble solids. Foliar applications of ZnO and SiO2 nanoparticles under water deficit treatments significantly enhanced yield and improved quality traits of potato plants. Moreover, significant and positive correlations were found among yield traits. Thus, it can be concluded that using ZnO NPs at 100 mg L−1 significantly improves potato productivity and quality traits by mitigating the negative effects of water deficit in arid regions. Full article
(This article belongs to the Special Issue Resilience to Biotic and Environmental Stresses in Horticultural Crops)
►▼ Show Figures

Figure 1

14 pages, 2186 KiB  
Article
Application of Biocat G, Selenium, and Chitosan to Counteract the Negative Effects of Cd in Broccoli Plants Grown in Soilless Culture
by Rafael Pérez-Millán, Jose Maria Cámara-Zapata, Juan Carlos Fernández-Zapata, Silvia Simón-Grao, Marina Alfosea-Simón, Ernesto Alejandro Zavala-González, Muhammad Adnan Shahid and Francisco García-Sánchez
Agronomy 2022, 12(6), 1327; https://doi.org/10.3390/agronomy12061327 - 30 May 2022
Cited by 2 | Viewed by 1466
Abstract
The accumulation of cadmium in plants produces phytotoxic damage and a decrease in crop yield. To avoid this effect, it is necessary to prevent its absorption by roots and reduce its toxicity in plant tissues. The current study was aimed to evaluate the [...] Read more.
The accumulation of cadmium in plants produces phytotoxic damage and a decrease in crop yield. To avoid this effect, it is necessary to prevent its absorption by roots and reduce its toxicity in plant tissues. The current study was aimed to evaluate the effect of the exogenous applications of Biocat G (fulvic/humic acids), selenium (Se), and chitosan to roots and leaves of broccoli plants exposed to Cd stress. The applied treatments were: (i) T1: Hoagland nutrient solution (NS), (ii) T2: NS + Cd at 3 mg L-1 (NS + Cd), (iii) T3: NS + Cd + root application of Biocat G (NS + Cd + BioG), (iv) T4: NS + Cd + foliar application of Se (NS + Cd + Se1), (v) T5: NS + Cd + root application of Se (NS + Cd + Se2), (vi) T6: NS + Cd + foliar application of chitosan (NS + Cd + chitosan1), and (vii) T7: NS + Cd + root application of chitosan (NS + Cd + chitosan2). The results showed that the exogenous application of Biocat G and Se (T3 and T5) ameliorated the adverse effects caused by Cd toxicity and significantly improved plant growth rate by decreasing Cd toxicity; besides, Biocat G was able to limit the transport of Cd from the leaves to the inflorescences, reducing the content of Cd in the edible part. These treatments (T3 and T5) yielded the best results, act on the plants by deactivating Cd toxicity, but they did not affect its accumulation in the plant tissue. In addition, Biocat G limits the transport of Cd from the non-edible to the edible part. Full article
(This article belongs to the Special Issue Resilience to Biotic and Environmental Stresses in Horticultural Crops)
►▼ Show Figures

Figure 1

16 pages, 1784 KiB  
Article
Physiological Responses and Phytoremediation Abilities of Cucumber (Cucumis sativus L.) under Cesium and Strontium Contaminated Soils
by Shahzaib Ali, Dan Wang, Abdul Rasheed Kaleri, Sadia Babar Baloch, Martin Brtnicky, Jiri Kucerik and Adnan Mustafa
Agronomy 2022, 12(6), 1311; https://doi.org/10.3390/agronomy12061311 - 30 May 2022
Cited by 1 | Viewed by 1984
Abstract
Soils contaminated with radionuclides pose a long-term radiation hazard to human health through food chain exposure and other pathways. The uptake, accumulation, and distribution of 133Cs, individual 88Sr, and combined 88Sr + 133Cs, with their physiological and biochemical responses [...] Read more.
Soils contaminated with radionuclides pose a long-term radiation hazard to human health through food chain exposure and other pathways. The uptake, accumulation, and distribution of 133Cs, individual 88Sr, and combined 88Sr + 133Cs, with their physiological and biochemical responses in greenhouse-potted soil-based cucumber (Cucumis sativus L.), were studied. The results from the present study revealed that the uptake, accumulation, TF, and BCF ability of cucumber for 88Sr + 133Cs were greater than for 133Cs and 88Sr while the concentration was the same in the soil (10, 20, 40, 80, and 160 mg kg−1). The highest 88Sr + 133Cs accumulation was 2128.5 µg g−1dw, and the highest accumulation values of 133Cs and 88Sr were 1738.4 µg g−1dw and 1818.2 µg g−1dw (in 160 mg kg−1), respectively. The lowest 88Sr + 133Cs, 133Cs, and 88Sr accumulation values were 416.37 µg g−1dw, 268.90 µg g−1dw, and 354.28 µg g−1dw (10 mg kg−1), respectively. MDA content was higher under 88Sr and 133Cs stress than under 88Sr + 133Cs stress. Chlorophyll content increased at 10 and 20 mg kg−1; however, it decreased with increasing concentrations (40, 80, and 160 mg kg−1). Proline content and the activities of CAT, POD, and SOD were lower under 133Cs and 88Sr than 88Sr + 133Cs stress. The 88Sr, 133Cs, and 88Sr + 133Cs treatment concentrations sequentially induced some enzymes over 60 days of exposure, suggesting that this complex of antioxidant enzymes—CAT, POD, and SOD—works in combination to reduce the impact of toxicity of 88Sr, 133Cs, and 88Sr + 133Cs, especially in young leaves. It is concluded that cucumber reveals considerable phytoremediation capabilities due to unique growth potential in contaminated substrate and is suitable for the bioreclamation of degraded soils. The plant is especially applicable for efficient phytoextraction of 88Sr + 133Cs contamination. Full article
(This article belongs to the Special Issue Resilience to Biotic and Environmental Stresses in Horticultural Crops)
►▼ Show Figures

Figure 1

12 pages, 1399 KiB  
Article
The Physiological Role of Inulin in Wild Cardoon (Cynara cardunculus L. var. sylvestris Lam.)
by Ferdinando Branca, Sergio Argento, Anna Maria Paoletti and Maria Grazia Melilli
Agronomy 2022, 12(2), 290; https://doi.org/10.3390/agronomy12020290 - 24 Jan 2022
Cited by 4 | Viewed by 2182
Abstract
Wild cardoon (Cynara cardunculus L.) is a widespread Mediterranean plant that accumulates inulin in its roots. This study aimed to analyze the enzyme systems involved in inulin metabolism in the roots of one Sicilian wild cardoon population in relation to the plant’s [...] Read more.
Wild cardoon (Cynara cardunculus L.) is a widespread Mediterranean plant that accumulates inulin in its roots. This study aimed to analyze the enzyme systems involved in inulin metabolism in the roots of one Sicilian wild cardoon population in relation to the plant’s growth and development stages. During the winter season, the plant showed slow growth; its biomass was represented mainly by leaves and saccharides were mobilized into its roots. During the spring season, the plant doubled its growth rate and differentiated its reproduction organs as a consequence of the cold conditions. The maximum activities of the 1-SST were recorded in line with the high sucrose and inulin levels in roots, which increased quickly. The increase in the 1-FEH activity suggests that fructan-hydrolyzing activity is associated with the sprouting and elongation of plant stalks. The peak of the invertase activity occurred before the 1-FEH peak. The inulin accumulation in the wild cardoon roots was associated with the plant’s reproduction. Sequential 1-SST and 1-FEH activities and the involvement of invertase and 1-FFT in carbohydrate mobilization, in response to the additional energy demand of the plant for stalk elongation before and for capitula development were observed, along with subsequent grain ripening. Full article
(This article belongs to the Special Issue Resilience to Biotic and Environmental Stresses in Horticultural Crops)
►▼ Show Figures

Figure 1

14 pages, 1004 KiB  
Article
Heat Stress Leads to Poor Fruiting Mainly Due to Inferior Pollen Viability and Reduces Shoot Photosystem II Efficiency in “Da Hong” Pitaya
by Yu-Chun Chu and Jer-Chia Chang
Agronomy 2022, 12(1), 225; https://doi.org/10.3390/agronomy12010225 - 17 Jan 2022
Cited by 5 | Viewed by 2433
Abstract
High summer temperatures (day/night: 40 °C/30 °C) are known to cause poor fruiting, reduced fruit/seed weight, and delayed fruit development in the “Da Hong” red-fleshed pitaya (Hylocereus polyrhizus); however, the mechanisms of these effects are unknown. This study examined how high [...] Read more.
High summer temperatures (day/night: 40 °C/30 °C) are known to cause poor fruiting, reduced fruit/seed weight, and delayed fruit development in the “Da Hong” red-fleshed pitaya (Hylocereus polyrhizus); however, the mechanisms of these effects are unknown. This study examined how high temperature (HT, 40 °C/30 °C) affects stamen and pistil fertility through pollination combinations and fruit set in “Da Hong” pitaya and evaluated photosystem II (PSII) efficiency in yellowed shoots (cladodes). The in-vitro pollen germination rate was significantly higher at optimal temperature (OT, 30 °C/20 °C) than at HT, which was also associated with a reduced flower length, poor fruit set, small fruit size, and low number of seeds after self-pollination. Meanwhile, fruit set and fruit development were remarkably improved by using the pollens taken from plants grown at OT and moderate temperature (MH, 35 °C/25 °C) after mutual cross pollination, indicating that the reduction in seed number caused by incomplete fertilization due to inferior pollen viability was the main cause of poor fruiting under HT rather than pistil or photoinhibition, although HT treatment was linked to reductions of PSII efficiency at both the adaxial and abaxial ends of shoots. The results suggested that pollen viability was most affected under HT stress; thus, yielding remarkably reduced fruiting. Full article
(This article belongs to the Special Issue Resilience to Biotic and Environmental Stresses in Horticultural Crops)
►▼ Show Figures

Figure 1

18 pages, 3524 KiB  
Article
Silicon Nanoparticles Mitigate Hypoxia-Induced Oxidative Damage by Improving Antioxidants Activities and Concentration of Osmolytes in Southern Highbush Blueberry Plants
by Zafar Iqbal, Ali Sarkhosh, Rashad Mukhtar Balal, Saeed Rauf, Naeem Khan, Muhammad Ahsan Altaf, Jose M. Camara-Zapata, Francisco Garcia-Sanchez and Muhammad Adnan Shahid
Agronomy 2021, 11(11), 2143; https://doi.org/10.3390/agronomy11112143 - 26 Oct 2021
Cited by 10 | Viewed by 2137
Abstract
Climate change exacerbates flooding problems due to hurricanes followed by heavy rains, particularly in sub-tropical regions. Consequently, submerged plants experience hypoxia stress which limits agronomic and horticultural crop growth and production. Hypoxia causes oxidative damage by accelerating the lipid peroxidation associated with O [...] Read more.
Climate change exacerbates flooding problems due to hurricanes followed by heavy rains, particularly in sub-tropical regions. Consequently, submerged plants experience hypoxia stress which limits agronomic and horticultural crop growth and production. Hypoxia causes oxidative damage by accelerating the lipid peroxidation associated with O2- and H2O2 levels. Additionally, hypoxia increases the accumulation of organic osmoprotectants and antioxidant activity, whereas it decreases the macronutrient (N, P, K, and Zn) uptake. This study aimed at investigating the effects of flooding-induced hypoxia stress on the growth and the physiological, biochemical, and nutritional characteristics of the hydroponically grown southern highbush blueberry (cv. Jewel) plants. In addition, the hypoxia-mitigating effects of conventional silicon (Si-C) and silicon nanoparticles (SiNPs) and their application methods (foliar vs. foliar and rootzone application) were also appraised. Both the Si-C and the SiNPs efficiently alleviated hypoxia-induced oxidative and osmotic damage to cells by enhancing the activities of the enzymatic antioxidants (ascorbate peroxidase, catalase, dehydroascorbate reductase, superoxide dismutase, peroxidase, guaiacol peroxidase, monodehydroascorbate, reductase); the non-enzymatic antioxidants (ascorbic acid and glutathione contents); and the accumulation of compatible solutes (proline and glycinebetaine) in leaves and roots. However, the SiNPs were more effective than Si-C at improving antioxidant activities and osmolytes formation. A strong negative correlation between the antioxidant activities and the lipid peroxidation rate was observed in the SiNP-treated plants under hypoxia stress. The SiNPs also regulated nutrient uptake by increasing the K, N, P, and Zn concentrations while decreasing Fe and Mn concentrations to a less toxic level. Blueberry plants treated with SiNPs responded more effectively to hypoxia stress by maintaining higher antioxidant and osmoprotectant concentrations than blueberry plants treated with Si-C. Additionally, the foliar and rootzone applications yielded better results than the foliar applications only. Full article
(This article belongs to the Special Issue Resilience to Biotic and Environmental Stresses in Horticultural Crops)
►▼ Show Figures

Graphical abstract

16 pages, 6976 KiB  
Article
Identification and Genomic Characterization of Pathogenic Bacillus altitudinis from Common Pear Trees in Morocco
by Naima Lemjiber, Khalid Naamani, Annabelle Merieau, Abdelhi Dihazi, Nawal Zhar, Hicham Jediyi and Amine M. Boukerb
Agronomy 2021, 11(7), 1344; https://doi.org/10.3390/agronomy11071344 - 30 Jun 2021
Cited by 3 | Viewed by 2624
Abstract
Bacterial burn is one of the major diseases affecting pear trees worldwide, with serious impacts on producers and economy. In Morocco, several pear trees (Pyrus communis) have shown leaf burns since 2015. To characterize the causal agent of this disease, we [...] Read more.
Bacterial burn is one of the major diseases affecting pear trees worldwide, with serious impacts on producers and economy. In Morocco, several pear trees (Pyrus communis) have shown leaf burns since 2015. To characterize the causal agent of this disease, we isolated fourteen bacterial strains from different parts of symptomatic pear trees (leaves, shoots, fruits and flowers) that were tested in planta for their pathogenicity on Louise bonne and Williams cultivars. The results showed necrotic lesions with a significant severity range from 47.63 to 57.77% on leaves of the Louise bonne cultivar inoculated with isolate B10, while the other bacterial isolates did not induce any disease symptom. 16S rRNA gene sequencing did not allow robust taxonomic discrimination of the incriminated isolate. Thus, we conducted whole-genome sequencing (WGS) and phylogenetic analyzes based on gyrA, gyrB and cdaA gene sequences, indicating that this isolate belongs to the Bacillus altitudinis species. This taxonomic classification was further confirmed by the Average Nucleotide Identity (ANI) and the in silico DNA-DNA hybridization (isDDH) analyzes compared to sixty-five Bacillus spp. type strains. The genome was mined for genes encoding carbohydrate-active enzymes (CAZymes) known to play a role in the vegetal tissue degradation. 177 candidates with functions that may support the in planta phytopathogenicity results were identified. To the best of our knowledge, this is the first data reporting B. altitudinis as agent of leaf burn in P. communis in Morocco. Our dataset will improve our knowledge on spread and pathogenicity of B. altitudinis genotypes that appears as emergent phytopathogenic agent, unveiling virulence factors and their genomic location (i.e., within genomic islands or the accessory genome) to induce trees disease. Full article
(This article belongs to the Special Issue Resilience to Biotic and Environmental Stresses in Horticultural Crops)
►▼ Show Figures

Figure 1

14 pages, 1152 KiB  
Article
Exogenous Salicylic Acid Improves Chilling Tolerance in Maize Seedlings by Improving Plant Growth and Physiological Characteristics
by Qian Zhang, Dongmei Li, Qi Wang, Xiangyu Song, Yingbo Wang, Xilang Yang, Dongling Qin, Tenglong Xie and Deguang Yang
Agronomy 2021, 11(7), 1341; https://doi.org/10.3390/agronomy11071341 - 30 Jun 2021
Cited by 10 | Viewed by 2310
Abstract
Maize (Zea mays L.) is a chilling-sensitive plant. Chilling stress in the early seedling stage seriously limits the growth, development, productivity and geographic distribution of maize. Salicylic acid (SA) is a plant growth regulator involved in the defenses against abiotic and biotic [...] Read more.
Maize (Zea mays L.) is a chilling-sensitive plant. Chilling stress in the early seedling stage seriously limits the growth, development, productivity and geographic distribution of maize. Salicylic acid (SA) is a plant growth regulator involved in the defenses against abiotic and biotic stresses as well as in plant development. However, the physiological mechanisms underlying the effects of foliar applied SA on different maize inbred lines under chilling stress are unclear. Two inbred lines, cold-sensitive cv. C546 and cold-tolerant cv. B125, were used to study the effects of SA on the growth and physiology of maize seedlings. The results showed that the application of SA at 50 mg/L on the leaves of maize seedlings under 4 °C decreased the relative electrolyte conductivity (REC) and the malondialdehyde (MDA) and reactive oxygen species (ROS) (H2O2 and O2−) content due to increased superoxide dismutase (SOD), peroxidase (POD), catalase (CAT) and ascorbate peroxidase (APX) activity; SA also improved photosynthesis in the seedlings through increased chlorophyll content, enhanced Pn and Gs, and decreased Ci. SA application also increased the proline content and the relative water content (RWC) in the maize seedlings, thereby improving their osmotic adjustment capacity. The increase rate caused by SA of plant height and dry weight in C546 were 10.5% and 5.4% higher than that in B125 under 4 °C. In conclusion, SA promotes maize seedling growth and physiological characteristics, thus enhancing chilling resistance and the effect of SA on the chilling resistance of cold-sensitive cv. was stronger than that on cold-tolerant cv. at the low temperature. Full article
(This article belongs to the Special Issue Resilience to Biotic and Environmental Stresses in Horticultural Crops)
►▼ Show Figures

Figure 1

15 pages, 1920 KiB  
Article
Bacillus Co-Inoculation Alleviated Salt Stress in Seedlings Cucumber
by Ruixue Qi, Wei Lin, Kaixuan Gong, Zeyu Han, Hui Ma, Miao Zhang, Qiannan Zhang, Yanming Gao, Jianshe Li and Xueyan Zhang
Agronomy 2021, 11(5), 966; https://doi.org/10.3390/agronomy11050966 - 13 May 2021
Cited by 12 | Viewed by 2831
Abstract
Soil salinity has become a serious threat to crop growth and productivity and has aggravated the gap between sustainable food supply and population growth. Application of plant growth-promoting rhizobacteria (PGPR) has emerged as a novel way of alleviating the harmful effects of salt [...] Read more.
Soil salinity has become a serious threat to crop growth and productivity and has aggravated the gap between sustainable food supply and population growth. Application of plant growth-promoting rhizobacteria (PGPR) has emerged as a novel way of alleviating the harmful effects of salt stress and improving soil nutrients. The aim of this study was to study the effects of exposure cucumber seedlings at one co-inoculation of Bacillus licheniformis and B. subtilis, a mitigation of salt stress in cucumber seedlings. In this study, we isolated salt tolerant (NX-3 and NX-4) and growth-promoting (NX-48, NX-59, and NX-62) bacteria from the rhizosphere of cucumber. NX-3 and NX-59 were identified as B. licheniformis, and NX-4, NX-48 and NX-62 were identified as B. subtilis. Under salt stress, relative to non-inoculation, co-inoculation with B. licheniformis and B. subtilis increased stem diameter and plant fresh weight. Moreover, the concentration of substrate available phosphorus increased (except for NX4-59). The catalase and sucrase activities of NX4-62 were the highest. Meanwhile, NX3-62 and NX3-59 had the highest phosphorus content and NX3-59 had the highest urease activities. Comprehensive analysis indicated that NX4-62 and NX3-59 showed the best effect on promoting cucumber seedlings growth, activating substrate nutrients, and alleviate salt stress in seedlings of cucumber. Full article
(This article belongs to the Special Issue Resilience to Biotic and Environmental Stresses in Horticultural Crops)
►▼ Show Figures

Figure 1

15 pages, 1584 KiB  
Article
Change of Physiological Properties and Ion Distribution by Synergistic Effect of Ca2+ and Grafting under Salt Stress on Cucumber Seedlings
by Xiaodong Wang, Zhiqian Lan, Lei Tian, Jianshe Li, Guankai Yang, Yanming Gao and Xueyan Zhang
Agronomy 2021, 11(5), 848; https://doi.org/10.3390/agronomy11050848 - 27 Apr 2021
Cited by 7 | Viewed by 2063
Abstract
Salinization is an important soil environmental problem, which severely restricts the sustainable production of cucumbers. Therefore, how to improve the salt tolerance of cucumbers is a global problem. Grafting improves the resistance of crops, and calcium ion (Ca2+) weakens the permeability [...] Read more.
Salinization is an important soil environmental problem, which severely restricts the sustainable production of cucumbers. Therefore, how to improve the salt tolerance of cucumbers is a global problem. Grafting improves the resistance of crops, and calcium ion (Ca2+) weakens the permeability of the plasma membrane. In this paper, grafting cucumber with NaCl-free treatment was the control treatment (CK). Under salt stress, grafting combined different concentrations of CaCl2 and non-grafted (NG) were considered as treatments. The synergistic effect of grafting and Ca2+ to relieve salt stress on cucumber seedlings was investigated. The results revealed that grafting (G), Ca2+, and their interaction significantly influenced plant growth, osmotic adjustment substances, enzyme activities, and iron distribution. Under salt stress, grafting increased the absorption of potassium ion (K+) and Ca2+ in cucumber stems and leaves, but compared with NG, it significantly reduced the accumulation of Na+ in those parts by 61.58–89.40%. Moreover, supplication suitable Ca2+ content had a similar effect. Supplemental Ca2+ promoted the shoot and root biomass. The 10 mM L−1 Ca2+ had the highest biomass, compared with CK and NG, an increase of 49.95% and 20.47%, respectively; the lowest sodium ion (Na+). The highest Ca2+ accumulation in cucumber stem and leaves was found in 10 mM L−1 Ca2+ treatment. Supplemental Ca2+ increased free proline (Pro) and decreased malondialdehyde (MDA) content during the entire salt stress period. At 11 days, compared with 0 mM L−1 Ca2+ treatment, pro content was increased by 4.70–25.31, and MDA content was decreased by 1.08–4.90 times, respectively. Superoxide dismutase (SOD) activity, relative growth rate of plant height (PH), and stem volume (SV), and K+/Na+ and K+/Ca2+ in cucumber leaves had significantly negative correlations with a salt damage score. The combination of grafting and supplemental 5–20 mM L−1 Ca2+ relieved salt damage to cucumber seedlings. The best synergistic effect was obtained with grafting and 10 mM L−1 Ca2+ treatment. Full article
(This article belongs to the Special Issue Resilience to Biotic and Environmental Stresses in Horticultural Crops)
►▼ Show Figures

Figure 1

Show export options expand_more Show export options expand_less
Select all
Export citation of selected articles as:
 
Displaying articles 1-11
Back to TopTop