boron and Dehydration

Therefore, the objective of the current research was to investigate the effects of foliar B nutrition on seed protein, oil, fatty acids, and sugars under water stress conditions. A repeated greenhouse experiment was conducted using different maturity group (MG) cultivars. Plants were well-watered with no foliar B (W - B), well-watered with foliar B (W + B), water-stressed with no foliar B (WS - B), and water-stressed with foliar B (WS + B). Foliar B was applied at rate of 0.45 kg · ha(-1) and was applied twice at flowering and at seed-fill stages. The results showed that seed protein, sucrose, fructose, and glucose were higher in W + B treatment than in W - B, WS + B, and WS - B. The increase in protein in W + B resulted in lower seed oil, and the increase of oleic in WS - B or WS + B resulted in lower linolenic acid. Foliar B resulted in higher nitrogen fixation and water stress resulted in seed δ (15)N and δ (13)C alteration. Increased stachyose indicated possible physiological and metabolic changes in carbon and nitrogen pathways and their sources under water stress. This research is beneficial to growers for fertilizer management and seed quality and to breeders to use (15)N/(14)N and (13)C/(12)C ratios and stachyose to select for drought tolerance soybean.

Topics: alpha-Linolenic Acid; Boron; Carbon Isotopes; Dehydration; Fructose; Glucose; Glycine max; Nitrogen Fixation; Nitrogen Isotopes; Plant Leaves; Plant Proteins; Seeds; Sucrose

Our previous research, conducted under well-watered conditions without fertilizer application, showed that fuzziness cottonseed trait resulted in cottonseed nutrition differences between fuzzy (F) and fuzzless (N) cottonseed. Under water stress conditions, B mobility is further limited, inhibiting B movement within the plant, affecting seed nutrition (quality). Therefore, we hypothesized that both foliar B and water stress can affect B mobility, altering cottonseed protein, oil, and mineral nutrition. The objective of the current research was to evaluate the effects of the fuzziness seed trait on boron (B) and seed nutrition under water stress and foliar B application using near-isogenic cotton lines (NILs) grown in a repeated greenhouse experiment. Plants were grown under-well watered conditions (The soil water potential was kept between -15 to -20 kPa, considered field capacity) and water stress conditions (soil water potential between -100 and -150 kPa, stressed conditions). Foliar B was applied at a rate of 1.8 kg B ha(-1) as H3BO3. Under well-watered conditions without B the concentrations of seed oil in N lines were higher than in F lines, and seed K and N levels were lower in N lines than in F lines. Concentrations of K, N, and B in leaves were higher in N lines than in F lines, opposing the trend in seeds. Water-stress resulted in higher seed protein concentrations, and the contribution of cell wall (structural) B to the total B exceeded 90%, supporting the structural role of B in plants. Foliar B application under well-watered conditions resulted in higher seed protein, oil, C, N, and B in only some lines. This research showed that cottonseed nutrition differences can occur due to seed fuzziness trait, and water stress and foliar B application can alter cottonseed nutrition.

Topics: Boron; Carbon; Cell Wall; Dehydration; Gossypium; Likelihood Functions; Nitrogen; Nutritional Physiological Phenomena; Phenotype; Plant Leaves; Plant Oils; Seeds; Soil; Species Specificity

Boron is an essential micronutrient for plants and is taken up in the form of boric acid (BA). Despite this, a high BA concentration is toxic for the plants, inhibiting root growth and is thus a significant problem in semi-arid areas in the world. In this work, we report the molecular basis for the inhibition of root growth caused by boron. We show that application of BA reduces the size of root meristems, correlating with the inhibition of root growth. The decrease in meristem size is caused by a reduction of cell division. Mitotic cell number significantly decreases and the expression level of key core cell cycle regulators is modulated. The modulation of the cell cycle does not appear to act through cytokinin and auxin signalling. A global expression analysis reveals that boron toxicity induces the expression of genes related with abscisic acid (ABA) signalling, ABA response and cell wall modifications, and represses genes that code for water transporters. These results suggest that boron toxicity produces a reduction of water and BA uptake, triggering a hydric stress response that produces root growth inhibition.

Topics: Abscisic Acid; Arabidopsis; Arabidopsis Proteins; Biological Transport; Boric Acids; Boron; Cell Wall; Dehydration; Gene Expression Profiling; Gene Expression Regulation, Plant; Meristem; Mitosis; Mutation; Oligonucleotide Array Sequence Analysis; Plant Growth Regulators; Plant Roots; Seedlings; Signal Transduction; Stress, Physiological; Water

This study investigated oxidative stress and the antioxidant response to boron (B) of chickpea cultivars differing in their tolerance to drought. Three-week-old chickpea seedlings were subjected to 0.05 (control), 1.6 or 6.4 mm B in the form of boric acid (H(3)BO(3)) for 7 days. At the end of the treatment period, shoot length, dry weight, chlorophyll fluorescence, B concentration, malondialdehyte content and the antioxidant enzymes superoxide dismutase (SOD), peroxidase (POX), catalase (CAT), ascorbate peroxidase (APX) and glutathione reductase (GR) were measured. The 1.6 mm B treatment did not cause significant changes in shoot length of cultivars, although shoot length increased in the drought-tolerant Gökce and decreased in the drought-sensitive Küsmen after 6.4 mm B treatment. Dry weights of both cultivars decreased with 6.4 mm B treatment. Chlorophyll fluorescence (Fv/Fm) did not change in Gökce at either B level. Nor did it change in Küsmen with 1.6 mm B but Fv/Fm decreased with 6.4 mm B. Boron concentration in the shoots of both cultivars increased significantly with increasing levels of applied B. Significant increases in total SOD activity were observed in shoots of both cultivars given 1.6 and 6.4 mm B. Shoot extracts exhibited five activity bands, two of which were identified as MnSOD and Cu/ZnSOD. In comparison to the control group, all enzyme activities (except APX and SOD) decreased with 1.6 mm B stress. GR activity decreased, while activities of CAT, POX and APX did not change with 6.4 mm B in Küsmen. On the other hand, activities of CAT, APX and SOD increased in Gökce at both B levels. In addition, lipid peroxidation was higher in Küsmen than in Gökce, indicating more damage by B to membrane lipids in the former cultivar. These results suggest that (i) Gökce is tolerant and Küsmen is sensitive to B, and (ii) B tolerance of Gökce might be closely related to increased capacity of the antioxidative system (total SOD, CAT and APX) to scavenge reactive oxygen species and thus suppress lipid peroxidation under B stress. To the best of our knowledge, this is the first report on the antioxidant response of chickpea seedlings to B toxicity.

Topics: Antioxidants; Ascorbate Peroxidases; Biological Transport; Boric Acids; Boron; Catalase; Chlorophyll; Cicer; Dehydration; Glutathione Reductase; Lipid Peroxidation; Oxidative Stress; Peroxidase; Peroxidases; Photosynthesis; Plant Proteins; Plant Shoots; Superoxide Dismutase

A 45-year-old white man ingested approximately two cups of boric acid crystals dissolved in water in a suicide attempt. Nausea, vomiting, greenish diarrhea, and dehydration occurred shortly thereafter. Two days later, he presented to the hospital with hypotension, metabolic acidosis, oliguric renal failure, a generalized erythematous rash, and several superficial skin abrasions. His condition failed to improve despite intravenous fluids and vasopressors. He later developed atrial fibrillation with a rapid ventricular response and could not be converted to a sinus rhythm. This rhythm deteriorated to electromechanical dissociation, and the patient died 17 hours after admission. The urine and whole blood boric acid concentrations approximately 52 hours after ingestion were 160 and 42 mg/dL, respectively. These results are equivalent to urine and blood boron concentrations of 28 and 7 mg/dL, respectively. A postmortem urine boron concentration was 29.4 mg/dL. The autopsy report listed boron toxicity as the cause of death. This is the only adult reported to die from acute boric acid ingestion in recent years and may be atypical since the patient was untreated for 3 days and presented with dehydration and renal function impairment. This case suggests that lack of adequate urine flow and dehydration increases the risk of boron toxicity.

Topics: Boric Acids; Boron; Dehydration; Hospitalization; Humans; Male; Middle Aged; Poisoning; Renal Insufficiency; Suicide, Attempted; Time Factors