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1.
Sci Rep ; 14(1): 2051, 2024 01 24.
Artigo em Inglês | MEDLINE | ID: mdl-38267535

RESUMO

Frequent droughts have led to an expansion of irrigated common bean (Phaseolus vulgaris L.) cultivation areas. An effective strategy to enhance water use efficiency and optimize crop growth is the application of silicon (Si) and potassium (K). However, the interaction between Si dosage, water regimes, and plant potassium status, as well as the underlying physiological mechanisms, remains unknown. This study aimed to assess the effects of Si doses applied via fertigation under various water regimes, in the presence and absence of potassium fertilization, on gas exchange, water use efficiency, and growth of Common beans in field conditions. Two experiments were conducted, one with and one without K supply, considering that the potassium content in the soil was 6.4 mmolc dm-3 in both experiments and a replacement dose of 50 kg ha was applied in the with K treatment, with the same treatments evaluated in both potassium conditions. The treatments comprised a 3 × 4 factorial design, encompassing three water regimes: 80% (no deficit), 60% (moderate water deficit), and 40% (severe water deficit) of soil water retention capacity, and four doses of Si supplied via fertigation: 0, 4, 8, and 12 kg ha-1. Where it was evaluated, content of photosynthetic pigments, fluorescence of photosynthesis, relative water content, leaf water potential and electrolyte extravasation, dry mass of leaves, stems and total. The optimal doses of Si for fertigation application, leading to increased Si absorption in plants, varied with decreasing soil water content. The respective values were 6.6, 7.0, and 7.1 kg ha-1 for the water regimes without deficit, with moderate water deficit, and with severe water deficit. Fertigation application of Si improved plant performance, particularly under severe water deficit, regardless of potassium status. This improvement was evident in relative water content, leaf water potential, and membrane resistance, directly impacting pigment content and gas exchange rates. The physiological effects resulted in enhanced photosynthesis in water-deficient plants, mitigating dry mass production losses. This research demonstrates, for the first time in common bean, the potential of Si to enhance irrigation efficiency in areas limited by low precipitation and water scarcity.


Assuntos
Phaseolus , Potássio , Silício , Secas , Solo
2.
Front Plant Sci ; 14: 1204836, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37324691

RESUMO

Introduction: Alkaline soils with iron (Fe) deficiency are found in many regions of the world, and the use of silicon (Si) can mitigate the damages caused by such deficiency. The aim of this study was to evaluate the effect of Si in mitigating a moderate deficiency of Fe in two energy cane cultivars. Methods: Two experiments were performed, one with the VX2 cultivar and the other with the VX3 cultivar of energy cane, which were cultivated in pots with sand and a nutrient solution. In both experiments, treatments followed a factorial scheme 2x2, designed based on the sufficiency and deficiency of Fe, being combined with the absence or presence of Si (2.5 mmol L-1), disposed in a randomized blocks design with six replicates. In the condition of Fe sufficiency, plants were cultivated in a solution containing 368 µmol L-1 of Fe, while plants cultivated under deficiency were initially submitted to cultivation with a 54 µmol L-1 concentration of Fe for 30 days, and later, with Fe complete omission for 60 days. The supply of Si was carried out by applying 15 fertirrigations with Si (via root and leaf) during the initial stage of seedling development, and after transplanting, the nutrient solution was added daily (via root). Results and discussion: Both cultivars of energy cane were sensitive to Fe deficiency in the absence of Si, impairing its growth by causing stress and pigment degradation, thus reducing the photosynthesis efficiency. The supply of Si mitigated the damages caused by Fe deficiency in both cultivars, by increasing Fe accumulation in new and intermediate leaves, stem, and roots in the VX2 cultivar, and in new, intermediate, and old leaves and stem in the VX3 cultivar, which in turn reduced stress and favored both the nutritional and photosynthesis efficiency, while increasing the dry matter production. Si by modulating physiological and nutritional mechanisms, mitigates Fe deficiency in two energy cane cultivars. It was concluded that Si can be used as a strategy to improve growth and nutrition of energy cane in environments that are susceptible to Fe deficiency.

3.
Sci Rep ; 12(1): 17487, 2022 10 19.
Artigo em Inglês | MEDLINE | ID: mdl-36261673

RESUMO

Production of sugarcane and more recently of energy cane strengthen renewable bioenergy production capacity. However, droughts resulting from climate change have limited the production of these crops. One of the strategies to attenuate water deficit damage in these crops is the use of silicate, which contributes to plant physiology. This strategy is likely to increase water use efficiency, thus promoting crop sustainability. Notwithstanding, studies on this issue are still incipient. This study assesses whether Si applied via fertigation and foliar spraying in the seedling production phase and as a complement after seedling transplanting to the soil is efficient in attenuating water deficit in sugarcane and energy cane. The study further elucidates physiological and biochemical mechanisms involved in this process. For this, the authors conducted two experiments: one with sugarcane and the other with energy cane. Treatments were arranged in randomized blocks with 5 replications, in a 2 × 2 factorial scheme. Factors consisted of the absence (-Si) and presence of Si (+ Si) applied via fertigation and foliar spraying; and two water regimes: 70% (without water deficit) and 30% (severe water deficit) of the soil water retention capacity. Silicon was supplied during the formation phase of presprouted seedlings and during the transplanting of seedlings to pots filled with samples of Entisol (Quartzipsamment). In these pots, water regimes were induced from 7 to 160 days after transplanting. Severe water deficit reduced the water content and water potential of plants. This situation induced oxidative stress and impaired gas exchange and photosynthetic water use efficiency, reducing plant growth. Silicon supply via fertigation in association with foliar spraying in the seedling formation phase with complementation after transplanting was efficient in increasing Si accumulation in the plants. Silicon was effective in attenuating severe water deficit damage up to initial culm formation through mechanisms that maintain water and physiological balance by favoring the antioxidant defense system in sugarcane and energy cane plants.


Assuntos
Saccharum , Antioxidantes/farmacologia , Água/farmacologia , Silício/farmacologia , Bengala , Plântula , Grão Comestível , Solo/química , Silicatos/farmacologia
4.
Front Plant Sci ; 13: 826512, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35498639

RESUMO

Climate change has prolonged periods of water deficit in sugarcane and energy cane crops. This condition induces an imbalance of the carbon (C): nitrogen (N): phosphorus (P) stoichiometric homeostasis, impairing accumulated nutrients from being converted into biomass. Silicon (Si) supplementation can mitigate the damage caused by water deficit in plants by improving the C:N:P balance, increasing C, N, and P use efficiencies and the biomass conversion, and reducing climate change effects on crops. This study assesses the beneficial effects of Si applied through fertigation associated with foliar spraying on the alleviation of damage caused by severe water deficit in sugarcane and energy cane for intermediate and long periods. In addition, the effects in maintenance of nutritional homeostasis we assessed and C, N, and P use efficiencies on sugarcane and energy cane under those conditions were increased. Four experiments were conducted during the first growth cycle of each species. The effect of fertigation associated with Si foliar spraying was evaluated by applying Si only during the seedling formation phase in sugarcane and energy cane grown under severe water deficit for 60 days after transplanting (intermediate period). Then, the effect of Si applied during seedling formation and supplemented after transplanting was evaluated in sugarcane and energy cane grown under severe water deficit for 160 days after transplanting (long period). The Si supply decreased C contents, modified the C:N:P ratio, and increased C, N, and P use efficiencies in plants of both species under water deficit at the intermediate and long periods after transplanting. The effects of applying Si through fertigation associated with foliar spraying during seedling formation mitigated the damage caused by severe water deficit in the intermediate period, which was mainly observed in sugarcane. When supplemented with Si after transplanting, the mitigating effects occurred in both species under severe long period water deficit. Therefore, the Si supply through fertigation associated with foliar spraying is a viable alternative to provide Si to the plant. It also comes with beneficial effects that partially reverse the damage to nutritional homeostasis and increase nutritional efficiency in plants under severe water deficit.

5.
Sci Rep ; 12(1): 6611, 2022 04 22.
Artigo em Inglês | MEDLINE | ID: mdl-35459764

RESUMO

Forages are one of the most cultivated crops in the world. However, nutritional deficiency is common, specifically in N, P, and Ca in many forage-growing regions. Silicon (Si) can attenuate the stress caused by nutritional deficiency, but studies on Si supply's effects on forage plants are still scarce. This research was carried out to evaluate whether the Si supply can mitigate the effects of N, P, and Ca deficiencies of two forages and the physiological and nutritional mechanisms involved. Two experiments were carried out with two forage species (Urochloa brizantha cv. Marandu and Megathyrsus maximum cv. Massai). We used nutrient solution under balanced nutrition conditions and nutritional stress due to the lack of N, P, and Ca combined with the -Si and +Si. The deficiencies of N, P, and Ca in both forages' cultivation caused damage to physiological and nutritional variables, decreasing the plant dry matter. However, in both forage species, the Si addition to the nutrient solution decreased the extravasation of cellular electrolytes and increased the content of phenolic compounds, the green colour index, the quantum efficiency of photosystem II, the efficiencies of use of N, P and Ca and the production of shoot dry matter. The beneficial effects of Si were evidenced in stressed and non-stressed plants. The research emphasised the advantage of using Si to grow U. brizantha and M. maximum under N, P, and Ca deficiency, contributing to their sustainable cultivation.


Assuntos
Desnutrição , Fósforo , Cálcio , Humanos , Nitrogênio , Silício/farmacologia
6.
Food Chem ; 370: 131017, 2022 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-34507213

RESUMO

The decrease in the use of K fertilizers may be relevant for developing countries that depend on imports, as well as for specific groups such as patients with chronic kidney disease, who have restricted K in their diets. However, the decrease in the use of K affects plant yield, requiring the study of alternatives to mitigate nutritional stress. Sodium is a beneficial element that can mitigate K deficiency, but studies on kale plants are lacking. We investigated the role of Na in kale grown with and without K in nutrient feed solution. Four treatments were used: abundant K, abundant K plus Na, deficient K, and deficient K plus Na. Low Na (2 mmol L-1) attenuated the symptoms of K deficiency in kale by minimizing leaf water loss and increasing pigment content, leaf area, and plant dry mass. The synergism between K and Na negatively affected the growth of kale plants.


Assuntos
Brassica , Fertilizantes , Humanos , Folhas de Planta , Sódio , Água
7.
Sci Rep ; 11(1): 20916, 2021 10 22.
Artigo em Inglês | MEDLINE | ID: mdl-34686731

RESUMO

Climate change has increased the occurrence of water deficit in regions where sugarcane and energy cane are cultivated, jeopardizing dry matter production of stems. It was hypothesized that the reasons behind this fact relate to C:N:P stoichiometric modifications in these species that impair the conversion rates of accumulated nutrients in the stems, which could be attenuated by supplying silicon (Si) to the crops. Thus, the aims of this study were to evaluate the effects of water deficit in sugarcane and energy cane ratoons in the presence and absence of Si, in the C:N:P stoichiometry of stems, in the use efficiency of these nutrients and in the accumulation of dry matter in stems. Two experiments were carried out, using sugarcane (Saccharum officinarum) and energy cane (S. spontaneum), cultivated in pots filled with a Typic Quartzipisamment. The treatments for both experiments were arranged in a factorial scheme 2 × 2, without (70% of the soil's water retention capacity) and with (30% of the capacity) water deficit, without and with the application of Si via fertirrigation, associated with foliar pulverization, both at a concentration of 2.5 mmol L-1, arranged in randomized blocks. The reduction in dry matter production of stems in both species caused by water deficit was due to modifications of the C, N and P stoichiometric homeostasis, but the benefit of Si in these plants when increasing dry matter production was not a reflection of the change in homeostasis, thus it may be involved in other mechanisms that remain unknown and should be further studied.

8.
Sci Rep ; 11(1): 19690, 2021 10 04.
Artigo em Inglês | MEDLINE | ID: mdl-34608202

RESUMO

Potassium (K) deficiency affects physiological performance and decreases vegetative growth in common bean plants. Although silicon (Si) supplied via nutrient solution or foliar application may alleviate nutritional stress, research on the bean crop is incipient. Thus, two experiments were carried out: initially, a test was performed to determine the best source and foliar concentration of silicon. Subsequently, the chosen Si source was supplied in nutrient solution via roots or foliar application to verify whether Si supply forms are efficient in alleviating the effects of K deficiency. For these purposes, a completely randomized 2 × 3 factorial design was used, with two levels of K: deficient (0.2 mmol L-1 of K) and sufficient (6 mmol L-1 of K); and Si: in nutrient solution via roots (2 mmol L-1 of Si) or foliar application (5.4 mmol L-1 of Si) and control (0 mmol L-1 of Si). Our findings revealed that Si supplied via foliar spraying using the source of sodium silicate and stabilized potassium at a concentration of 5.4 mmol L-1 was agronomically viable for the cultivation of bean plant. K deficiency, when not supplied with silicon, compromised plant growth. Moreover, root-and-foliar-applied Si attenuated the effects of K deficiency as it increased chlorophylls and carotenoids content, photosynthetic activity, water use efficiency and vegetative growth. For the first time, the role of Si to mitigate K deficiency in the bean crop was evidenced, with a view to further research on plants that do not accumulate this beneficial element.


Assuntos
Phaseolus/metabolismo , Raízes de Plantas/metabolismo , Deficiência de Potássio/metabolismo , Silício/administração & dosagem , Fenótipo , Desenvolvimento Vegetal , Folhas de Planta , Fenômenos Fisiológicos Vegetais , Estresse Fisiológico
9.
PLoS One ; 16(6): e0252866, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34086839

RESUMO

The intensity damages caused by nutritional deficiency in growing plants can vary with nutrients. The effects caused by nutrient omission in the plant nutritional efficiency in relation to the absorption and use of the missing nutrient, and the reasons why these damages reflect in other nutrients have not yet been reported in the culture of scarlet eggplant. A better understanding of the nutritional mechanisms involved may clarify why certain nutrients cause greater limitations than other during plants growth. Thus, this study was designed with the aim of evaluating the damages caused by macronutrients deficiency in the culture of scarlet eggplant in the accumulation of these nutrients, nutritional deficiency, plants growth and in visual symptoms. The experiment was carried out in a controlled environment where plants were cultivated in a hydroponic system. Treatments consisted of supplying a complete Hoagland and Arnon solution (CS), and other nutrient solutions with individual omissions of nitrogen (-N), phosphorus (-P), potassium (-K), calcium (-Ca), magnesium (-Mg) and sulphur (-S). When a nutrient deficiency arose, nutritional analyses, growth and visual symptoms were analyzed. The omissions of N, S and K in the nutrient solution resulted in lower accumulation of all macronutrients in both the above and below ground biomass. Individual omissions resulted in nutritional imbalances with reflexes in the absorption efficiencies and use of the missing nutrient, as well as of other nutrients, revealing that the metabolism involves multiple nutritional interactions. Losses of nutritional efficiencies of macronutrients caused detrimental effects on plants growth, with reduced height, stem diameter, number of leaves, leaf area, and biomass production in above ground and below ground. From the losses in production in above ground biomass, the order of macronutrients limitation was N, S, K, Ca, Mg, and P, with reductions of 99, 96, 94, 76, 51 and 46%, respectively, in comparison to plants cultivated in CS. The most limiting nutrients were N, S, and K, seen that its deficiencies affected the metabolism of all other nutrients. This study demonstrates the importance of an adequate nutritional management of N, S, and K in the cultivation of scarlet eggplant.


Assuntos
Desnutrição/patologia , Nutrientes/análise , Nutrientes/metabolismo , Folhas de Planta/crescimento & desenvolvimento , Solanum melongena/crescimento & desenvolvimento , Magnésio/análise , Nitrogênio/análise , Fósforo/análise , Folhas de Planta/metabolismo , Potássio/análise , Solanum melongena/metabolismo , Enxofre/análise
10.
PLoS One ; 15(10): e0240847, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33057406

RESUMO

Water deficit limits the establishment of sugarcane plants from pre-sprouted seedlings (PSS). Silicon (Si) can mitigate such stress, and your supply in plants with the active absorption mechanism is carried out through roots. However, foliar spraying has been practiced to supply Si in PSS production nurseries. Althought it is known that Si via roots can alter C: N: P ratios, nothing has been reported about its supply via foliar spraying, nor whether such changes interfere with structural nutrient use efficiency and with plant physiological responses. Thus, this study aimes to asses whether Si foliar spraying changes C: N: P ratios and increases the nutritional efficiency of PSS, as well as whether water deficiency interferes with such a relationships. For these purposes, three experiments were carried out. In experiment I, treatments consisted of two sugarcane cultivars (CTC 4 and RB 966928) and three Si supply forms (in nutrient solution via roots [SiR], via foliar spraying [SiL], and one control with the absence of Si [-Si]). The same Si supply forms were used in the other two experiments. In experiment II, a short-term water deficit was induced by polyethylene glycol addition to nutrient solution (-0.6 MPa) for three days. In experiment III, a long-term water deficit was imposed using levels of soil water retention capacity (70% [no water deficit], 50% [moderate water deficit], and 30% [severe water deficit] for 30 days. Our findings revealed that Si supply decreased C concentrations regardless of water conditions and that N and P concentrations varied with Si supply form and water deficit level. Moreover, root- and foliar-applied Si modified the C: N: P stoichiometry and increased C use efficiency in PSS, which thus increased N and P use efficiencies. Such an increased nutritional performance helped adjust physiological parameters and increase dry matter yield in PSS, both under water stress and non-stress conditions. Further, Si foliar spraying promoted structural effects on PSS regardless of water conditions, even if sugarcane has an active absorption via roots. In conclusion, foliar spraying can be used to supply Si in PSS production nurseries.


Assuntos
Saccharum , Plântula , Silício , Carbono/metabolismo , Desidratação , Nitrogênio/metabolismo , Fósforo/metabolismo , Folhas de Planta/efeitos dos fármacos , Folhas de Planta/metabolismo , Raízes de Plantas/efeitos dos fármacos , Raízes de Plantas/metabolismo , Saccharum/efeitos dos fármacos , Saccharum/crescimento & desenvolvimento , Saccharum/metabolismo , Plântula/efeitos dos fármacos , Plântula/metabolismo , Silício/administração & dosagem , Silício/farmacologia , Solo/química
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