Silicon Application Induced Alleviation of Aluminum Toxicity in Xaraés Palisadegrass

Aluminum (Al) toxicity is a major abiotic constraint for agricultural production in acidic soils that needs a sustainable solution to deal with plant tolerance. Silicon (Si) plays important roles in alleviating the harmful effects of Al in plants. The genus Urochloa includes most important grasses and hybrids, and it is currently used as pastures in the tropical regions. Xaraés palisadegrass (Urochloa brizantha cv. Xaraés) is a forage that is relatively tolerant to Al toxicity under field-grown conditions, which might be explained by the great uptake and accumulation of Si. However, studies are needed to access the benefits of Si application to alleviate Al toxicity on Xaraés palisadegrass nutritional status, production, and chemical–bromatological composition. The study was conducted under greenhouse conditions with the effect of five Si concentrations evaluated (0, 0.3, 0.6, 1.2, and 2.4 mM) as well as with nutrient solutions containing 1 mM Al in two sampling dates (two forage cuts). The following evaluations were performed: number of tillers and leaves, shoot biomass, N, P, K, Ca, Mg, S, B, Cu, Fe, Mn, Zn, Al, and Si concentration in leaf tissue, Al and Si concentration in root tissue, neutral detergent fiber (NDF), and acid detergent fiber (ADF) content in Xaraés palisadegrass shoot. Silicon supply affected the relation between Si and Al uptake by increasing root Al concentration in detriment to Al transport to the leaves, thereby alleviating Al toxicity in Xaraés palisadegrass. The concentrations between 1.4 and 1.6 mM Si in solution decreased roots to shoots Al translocation by 259% (from 3.26 to 1.26%), which contributed to a higher number of leaves per plot and led to a greater shoot dry mass without affecting tillering. Xaraés palisadegrass could be considered one of the greatest Si accumulator plants with Si content in leaves above 4.7% of dry mass. In addition, Si supply may benefit nutrient-use efficiency with enhanced plant growth and without compromising the chemical–bromatological content of Xaraés palisadegrass.

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Nutritional and Structural Role of Silicon in Attenuating Aluminum Toxicity in Sugarcane Plants

10.21203/rs.3.rs-614532/v1 ◽

2021 ◽

Author(s):

Gilmar da Silveira Sousa Junior ◽

Alexander Calero Hurtado ◽

Jonas Pereira de Souza Junior ◽

Renato de Mello Prado ◽

Durvalina Maria Mathias Dos Santos

Keyword(s):

Adverse Effect ◽

Growth Medium ◽

Aluminum Sulfate ◽

Aluminum Toxicity ◽

Al Toxicity ◽

Shoot Biomass ◽

Use Efficiency ◽

Hydroponic Conditions ◽

Si Addition

Abstract Purpose: We investigated the interactive role of Si-mediated attenuation to aluminum (Al) toxicity in two sugarcane cultivars (‘CTC9002’ and ‘CTC9003’) grown in hydroponic conditions. Methods: Two pot experiments were distributed in randomized blocks in a factorial design (4 × 2) with four replications. The treatments consisted of 0, 10, 15, and 20 mg L−1 Al (as aluminum sulfate [Al2 (SO4)3·18H2O)], which were combined with the absence and presence of Si [(2.0 mmol L−1 as potassium silicate (K2SiO3)]. Results: Both sugarcane cultivars (‘CTC9002’ and ‘CTC9003’) were affected by Al toxicity (above 10 mg L−1), resulting in nutritional disorders and decreasing plant growth, which were drastically reversed by Si addition in the growth medium. Si supplementation decrease Al concentration and translocation to the shoots of both cultivars when Al and Si were simultaneously supplied in the growth medium. We demonstrated that in shoots of both sugarcane seedlings, Si concentration are positively related to the lignin concentrations (ranging from 12.0% to 41% in cv. ‘CTC9002’ and 12% to 47% in cv. ‘CTC9003’). In addition, Si fertilization enhanced mineral nutrition and use efficiency of macros- and micronutrients, irrespective of the cultivar. Therefore, the use of cultivar ‘CTC9003’ under Si fertilization is more recommended to cope with the adverse effect caused by Al stress. Conclusions: The findings of this study suggest that Si fertilization in sugarcane seedlings is an economic and viable strategy strongly recommended to cope with the adverse effect caused by Al toxicity at concentrations less than 20 mg L−1, which lead to increase the shoot biomass production.

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Recent Advances in Understanding Mechanisms of Plant Tolerance and Response to Aluminum Toxicity

Sustainability ◽

10.3390/su13041782 ◽

2021 ◽

Vol 13 (4) ◽

pp. 1782

Author(s):

Yunmin Wei ◽

Rongrong Han ◽

Yonghong Xie ◽

Caode Jiang ◽

Yongxiong Yu

Keyword(s):

Plant Growth ◽

Aluminum Toxicity ◽

Plant Growth Promoting Rhizobacteria ◽

Al Toxicity ◽

Plant Production ◽

Plant Tolerance ◽

Al Stress ◽

Transgenic Breeding ◽

Plant Growth Promoting ◽

Growth Promoting

Aluminum (Al) toxicity is a major environmental stress that inhibits plant growth and development. There has been impressive progress in recent years that has greatly increased our understanding of the nature of Al toxicity and its mechanisms of tolerance. This review describes the transcription factors (TFs) and plant hormones involved in the adaptation to Al stress. In particular, it discusses strategies to confer plant resistance to Al stress, such as transgenic breeding, as well as small molecules and plant growth-promoting rhizobacteria (PGPRs) to alleviate Al toxicity. This paper provides a theoretical basis for the enhancement of plant production in acidic soils.

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Plant Biostimulants from Cyanobacteria: An Emerging Strategy to Improve Yields and Sustainability in Agriculture

Plants ◽

10.3390/plants10040643 ◽

2021 ◽

Vol 10 (4) ◽

pp. 643

Author(s):

Gaia Santini ◽

Natascia Biondi ◽

Liliana Rodolfi ◽

Mario R. Tredici

Keyword(s):

Nutrient Use Efficiency ◽

Biologically Active ◽

Future Research ◽

Plant Tolerance ◽

Metabolic Plasticity ◽

Nutrient Use ◽

Cyanobacterial Species ◽

Use Efficiency ◽

Promising Source ◽

Plant Treatment

Cyanobacteria can be considered a promising source for the development of new biostimulants as they are known to produce a variety of biologically active molecules that can positively affect plant growth, nutrient use efficiency, qualitative traits of the final product, and increase plant tolerance to abiotic stresses. Moreover, the cultivation of cyanobacteria in controlled and confined systems, along with their metabolic plasticity, provides the possibility to improve and standardize composition and effects on plants of derived biostimulant extracts or hydrolysates, which is one of the most critical aspects in the production of commercial biostimulants. Faced with these opportunities, research on biostimulant properties of cyanobacteria has undergone a significant growth in recent years. However, research in this field is still scarce, especially as regards the number of investigated cyanobacterial species. Future research should focus on reducing the costs of cyanobacterial biomass production and plant treatment and on identifying the molecules that mediate the biostimulant effects in order to optimize their content and stability in the final product. Furthermore, the extension of agronomic trials to a wider number of plant species, different application doses, and environmental conditions would allow the development of tailored microbial biostimulants, thus facilitating the diffusion of these products among farmers.

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Effects of 1-aminocyclopropane-1-carboxylate-deaminase–Producing Bacteria on Perennial Ryegrass Growth and Physiological Responses to Salinity Stress

Journal of the American Society for Horticultural Science ◽

10.21273/jashs.141.3.233 ◽

2016 ◽

Vol 141 (3) ◽

pp. 233-241 ◽

Cited By ~ 3

Author(s):

Liang Cheng ◽

Ning Zhang ◽

Bingru Huang

Keyword(s):

Salinity Stress ◽

Perennial Ryegrass ◽

Photochemical Efficiency ◽

Acc Deaminase ◽

Nutrition Status ◽

Shoot Biomass ◽

Leaf Water Content ◽

Salinity Treatment ◽

Plant Tolerance ◽

Water Control

The accumulation of 1-aminocyclopropane-1-carboxylate (ACC), which is a precursor for ethylene production, in plant roots exposed to salinity stress can be detrimental to plant growth. The objectives of this study were to determine whether inoculating roots with bacteria containing deaminase enzymes that break down ACC (ACC-deaminase) could improve plant tolerance to salinity in perennial ryegrass (Lolium perenne) and to examine growth and physiological factors, as well as nutrition status of plants affected by the ACC-deaminase bacteria inoculation under salinity stress. Plants of perennial ryegrass (cv. Pangea) were inoculated with either Burkholderia phytofirmans PsJN or Burkholderia gladioli RU1 and irrigated with either fresh water (control) or a 250 mm NaCl solution to induce salinity stress. The bacterium-inoculated plants had less ACC content in shoots and roots under both nonstressed and salinity conditions. Salinity stress inhibited root and shoot growth, but the bacterium-inoculated plants exhibited higher visual turf quality (TQ), tiller number, root biomass, shoot biomass, leaf water content, and photochemical efficiency, as well as lower cellular electrolyte leakage (EL) under salinity stress. Plants inoculated with bacteria had lower sodium content and higher potassium to sodium ratios in shoots under salinity stress. Shoot and root nitrogen content and shoot potassium content increased, whereas shoot and root calcium, magnesium, iron, and aluminum content all decreased due to bacterial inoculation under salinity treatment. ACC-deaminase bacteria inoculation of roots was effective in improving salinity tolerance of perennial ryegrass and could be incorporated into turfgrass maintenance programs in salt-affected soils.

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Investigating the Type of Gene Action Conditioning Tolerance to Aluminum (Al) Toxicity in Tropical Maize

Asian Plant Research Journal ◽

10.9734/aprj/2019/v2i430051 ◽

2019 ◽

pp. 1-8

Author(s):

Victoria Ndeke ◽

Langa Tembo

Keyword(s):

Root Length ◽

Aluminum Toxicity ◽

Gene Action ◽

Abiotic Factors ◽

Al Toxicity ◽

High Yield ◽

Small Scale ◽

Tropical Maize ◽

Maize Varieties ◽

Small Scale Farmers

Maize is a third important cereal crop in the world after wheat and rice. In Zambia, it is an important staple crop. Its production is however hampered by both biotic and abiotic factors. Among the abiotic factors, Aluminum (Al) toxicity causes high yield losses and is directly linked to acidic soils. Application of lime can ameliorate this problem, but it is expensive for small scale farmers. Developing maize varieties that are tolerant to Al toxicity is cheaper and feasible for small scale farmers. The purpose of this research was to investigate the type of gene action conditioning tolerance to aluminum toxicity in tropical maize. Eleven inbred lines were mated in an 8 male (4 moderately tolerant and 4 susceptible) x 3 female (resistant) North Carolina Design II. Results revealed that general combining ability (GCA) effects due to both males and females were highly significant (P≤ 0.001) for root biomass. The shoot length GCA effects due to both male and female respectively were significant (P≤ 0.01). Similarly, the GCA effects due to females and males for root length were significant, P≤ 0.01 and P≤ 0.05 respectively. The genotype CML 511 had the most desirable significant GCA effect value (1.40) for root length among the male lines while CML 538 had the most desirable significant GCA effect value (0.92) among the female lines. The baker’s ratio for root length was found to be 0.49 implying that both additive and non-additive gene action were important in conditioning aluminum toxicity tolerance in tropical maize.

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Pseudopestalotiopsis gilvanii sp. nov. and Neopestalotiopsis formicarum leaves spot pathogens from guarana plant: a new threat to global tropical hosts

Phytotaxa ◽

10.11646/phytotaxa.489.2.2 ◽

2021 ◽

Vol 489 (2) ◽

pp. 121-139

Author(s):

GILVANA F. GUALBERTO ◽

ARICLÉIA DE M. CATARINO ◽

THIAGO F. SOUSA ◽

JEFERSON C. CRUZ ◽

ROGÉRIO E. HANADA ◽

...

Keyword(s):

Plant Pathogen ◽

Elaeis Guineensis ◽

Elongation Factor ◽

Leaf Tissue ◽

Euterpe Oleracea ◽

Internal Transcribed Spacer Region ◽

Tropical Regions ◽

Tropical Plants ◽

Wide Range ◽

Genes Encoding

Pestalotioid species (Pestalotiopsis, Pseudopestalotiopsis and Neopestalotiopsis) cause extremely damaging diseases in a wide range of hosts across the word. Recently, pestalotioid strains isolated from damaged guarana leaf tissue were subject to morphological and molecular characterization. Six monosporic isolates were obtained and analysed based on the following conidial characters: length, width, septation, absence or presence of basal appendage, number and length of apical appendages. For phylogenetic inference, sequences of the Internal Transcribed Spacer region (ITS), partial sequences of the genes encoding the translation elongation factor 1-α (tef1-α) and β-tubulin (tub2) were used. Three out of six strains analysed were identified as Neopestalotiopsis formicarum, while the three other isolates are described here as a new species of Pseudopestalotiopsis, named Ps. gilvanii sp. nov.. The pathogenicity of N. formicarum and Ps. gilvanii were confirmed following Koch’s postulate. Besides guarana, the potential of N. formicaram and Ps. gilvanii to cause diseases in other economically important tropical plants were investigated. Ps. gilvanii was pathogenic to açaí palms (Euterpe oleracea, E. precatoria), and oil palm (Elaeis guineensis), but not to banana (Musa paradisiaca var. pacovan) and rubber trees (Hevea brasiliensis). N. formicarum was not pathogenic to rubber trees but was pathogenic to other species tested. To our knowledge this is the first report of N. formicarum as a plant pathogen in the guarana plant, and Ps. gilvanii as novel plant pathogen capable of causing disease in important plant crops from tropical regions.

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Importance of Mineral Nutrition for Mitigating Aluminum Toxicity in Plants on Acidic Soils: Current Status and Opportunities

International Journal of Molecular Sciences ◽

10.3390/ijms19103073 ◽

2018 ◽

Vol 19 (10) ◽

pp. 3073 ◽

Cited By ~ 23

Author(s):

Md. Rahman ◽

Sang-Hoon Lee ◽

Hee Ji ◽

Ahmad Kabir ◽

Chris Jones ◽

...

Keyword(s):

Plant Growth ◽

Mineral Nutrition ◽

Aluminum Toxicity ◽

Low Cost ◽

Acid Soils ◽

Cost Effective ◽

Al Toxicity ◽

Current Status ◽

Root Tips ◽

Acidic Soils

Aluminum (Al) toxicity is one of the major limitations that inhibit plant growth and development in acidic soils. In acidic soils (pH < 5.0), phototoxic-aluminum (Al3+) rapidly inhibits root growth, and subsequently affects water and nutrient uptake in plants. This review updates the existing knowledge concerning the role of mineral nutrition for alleviating Al toxicity in plants to acid soils. Here, we explored phosphorus (P) is more beneficial in plants under P-deficient, and Al toxic conditions. Exogenous P addition increased root respiration, plant growth, chlorophyll content, and dry matter yield. Calcium (Ca) amendment (liming) is effective for correcting soil acidity, and for alleviating Al toxicity. Magnesium (Mg) is able to prevent Al migration through the cytosolic plasma membrane in root tips. Sulfur (S) is recognized as a versatile element that alleviates several metals toxicity including Al. Moreover, silicon (Si), and other components such as industrial byproducts, hormones, organic acids, polyamines, biofertilizers, and biochars played promising roles for mitigating Al toxicity in plants. Furthermore, this review provides a comprehensive understanding of several new methods and low-cost effective strategies relevant to the exogenous application of mineral nutrition on Al toxicity mitigation. This information would be effective for further improvement of crop plants in acid soils.

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Productive and nutritional characteristics of Piatã-grass in integrated systems

Revista Brasileira de Saúde e Produção Animal ◽

10.1590/s1519-99402018000200001 ◽

2018 ◽

Vol 19 (2) ◽

pp. 144-156

Author(s):

Jeskarlândia Silva Barros ◽

Laura Cristina Souza Castro ◽

Fabiane de Lima Silva ◽

Fabiana Villa Alves ◽

Roberto Giolo de Almeida ◽

...

Keyword(s):

Leaf Blade ◽

Dry Mass ◽

Canopy Height ◽

Neutral Detergent Fiber ◽

Integrated Systems ◽

In Vitro Digestibility ◽

Significant Difference ◽

Nutritional Characteristics ◽

Sampling Points

SUMMARY This study aimed to evaluate the pasture productive and nutritional characteristics of Brachiaria brizantha cv. BRS Piatã in integrated systems with different densities of trees. Considering as plot the systems: integrated crop-livestock-forest with rows of trees (eucalyptus) spaced at 14 m and 357 trees ha-1 (ICLF-14m), ICLF with rows of trees spaced at 22 m and 227 trees ha-1 (ICLF-22m) and the integrated crop-livestock (ICL) with five remaining native trees ha-1; period of the year as subplots, and sampling points as subsubplots (A, B C, D, and E) arranged perpendicular to trees alleys. It was evaluated the production of forage and leaf blade dry mass, leaf:stem ratio, soil coverage, radiation photosynthetically active interception, canopy height, crude protein (CP), neutral detergent fiber (NDF), in vitro digestibility of organic matter (IVDOM) of the leaf blade, and stem associated with the leaf sheath. There was a significant difference (P<0.05) for all variables due to the month within the integrated systems. Mainly in January and March, showing the forage and leaf blade dry mass reduction due to a higher trees density. System with higher trees density showed the lowest soil coverage and canopy height sampling points A and E in ICLF-22m showed lower forage and leaf blade dry mass production and soil coverage. The system with higher trees density showed lower value of NDF of the leaf blade, and higher CP contents. The IVDOM of the leaf blade was higher in ICLF systems. For the evaluated parameters the best results were for the ICLF-22m.

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Germination and seedling characteristics of drought-stressed corn seed as influenced by seed priming with potassium nano-chelate and sulfate fertilizers

Acta agriculturae Slovenica ◽

10.14720/aas.2016.107.1.12 ◽

2016 ◽

Vol 107 (1) ◽

pp. 113 ◽

Cited By ~ 1

Author(s):

Maryam ZAHEDIFAR ◽

Sadegh ZOHRABI

Keyword(s):

Drought Stress ◽

Seed Priming ◽

Dry Mass ◽

Plant Tolerance ◽

Corn Seed ◽

Seedling Traits ◽

Corn Seedling ◽

Seminal Roots ◽

Mean Germination Time ◽

Seedling Characteristics

Effect of seed-priming with potassium (K) sources (K-nano-chelate, KNC, and sulfate (0, 2 and 4 %)) under drought stress (DS) conditions (0, -0.3, -0.6, -0.9, -1.2 and -1.5 MPa water potential) on the corn seedling traits was studied. Drought stress decreased the germination indices and seedling vigor. The highest germination, seminal root fresh and dry mass (RFM and RDM) was obtained in KNC primed seeds at -0.3 MPa DS. Mean germination time increased under DS conditions mainly in non-primed seeds. Increasing DS to -1.2 MPa led to decrease in RFM and RDM. Influence of DS on the fresh mass of shoots was more severe than on seminal roots. The highest shoots and seminal roots length was observed in 4 % KNC without any DS. Proper priming can be suggested to increase the plant tolerance under DS.

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Response of Common Bean Cultivars and Lines to Aluminum Toxicity

Agronomy ◽

10.3390/agronomy10020296 ◽

2020 ◽

Vol 10 (2) ◽

pp. 296

Author(s):

José dos Santos Neto ◽

Jessica Delfini ◽

Tiago Willian Silva ◽

Anderson Akihide Hirose ◽

João Marcos Novais ◽

...

Keyword(s):

Common Bean ◽

Early Identification ◽

Cell Expansion ◽

Aluminum Toxicity ◽

Al Toxicity ◽

Yield Losses ◽

Phaseolus Vulgaris L ◽

Second Stage ◽

Series Of Experiments ◽

The Common

The soils in the common bean-producing regions (Phaseolus vulgaris L.) of Brazil are usually acid and conta\y66\yin toxic levels of aluminum (Al) for plants. This ion causes yield losses by inhibiting root cell expansion, thus reducing water and nutrient uptake. This study investigates the optimal Al concentration for the screening of genotypes in hydroponics cultivation and tries to identify cultivars and lines for cultivation in Al-toxic soils. The study consisted of two series of experiments. In the first one, four cultivars were evaluated at five Al concentrations (0, 2.5, 5, 7.5 and 10 ppm) and in the second, four independent tests were carried out (1-carioca, 2-black, 3-red, and 4-white), each with seven genotypes and two Al concentrations (0 and 4 ppm). The optimized concentration of Al in the first stage was 4 ppm, which allowed the early identification of genotypes with less affected development under Al toxicity in the second stage. The common bean cultivars IPR Quero-Quero (carioca group), BRS Esplendor (black group), KID 44 (red group), and WLine 5 (white group) may be indicated for cultivation under Al toxicity.

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