The effects of arsenic on the growth and nutritional status of Anadenanthera peregrina,a Brazilian savanna tree

Anadenanthera peregrina is a Brazilian savanna tree species that occurs naturally in arsenic (As)‐contaminated areas, and its As resistance has been associated with arbuscular mycorrhizal–fungi (AMF) symbiosis. A plant's ability to survive in stressful environments is correlated with its nutrition status, which can be affected by As uptake. The present study evaluated the influence of As on the concentrations and distribution of nutrients in the roots and shoots of A. peregrina grown in the absence of AMF. These plants were grown in substrates spiked with 0, 10, 50, and 100 mg As kg^–1 for 25 d under greenhouse conditions, and the concentrations of essential macro‐ (P, K, Ca, Mg, N, and S) and micro‐ (Fe, Mn, Cu, Zn, B, and Mo) nutrients in the roots and shoots were then determined. Enhanced As levels increased the concentrations of P, S, and N and decreased Ca, Mg, and Fe. Although the deleterious effects of As on the plants were striking, the internal As levels were high, which indicated some tissue tolerance of A. peregrina.     

Improvement of degraded physical attributes of a saline-sodic soil as influenced by phytoremediation and soil conditioners

This study aimed to evaluate the use of phytoremediation and soil conditioners in the recovery of physical attributes of a saline-sodic Fluvic Neossol in Brazil Northeast. The applied treatments were: Atriplex nummularia L., as phytoremediation plant, due to its ability to extract salts from the soil; organic conditioners, such as bovine and sheep manure; gypsum and polymer, as chemical conditioners. Samples with preserved structure were collected at the time of the experiment installation and 18 months after in the layers 0–10 cm and 10–30 cm. The analyzed attributes were: water dispersed clay, dispersion index, bulk density, penetration resistance, soil porosity, and saturated hydraulic conductivity. The use of sheep manure, gypsum and polymer promoted an increase in saturated hydraulic conductivity in the 0–10 cm layer from 4.51 to 16.37 cm day^?1, 11.26 to 23.95 cm day^?1 and 7.24 to 22.77 cm day^?1, respectively. Gypsum increased the macroporosity in the superficial layer by 42.6%. Atriplex and polymer were more efficient at reducing soil penetration resistance. The polymer was more efficient at improving the physical properties. However, it is necessary to consider phytoremediation with Atriplex as a more sustainable alternative that can still be used as complementary fodder in animal feed.     

Biofortification of soybean grains with foliar application of Li sources

Abstract

Biofortification of soybean grains with lithium (Li) is a strategy to improve a food with high social acceptance, in order to promote health benefits. The aim of this work was to evaluate the development of plants and the production of biofortified soybeans with two Li sources. The experiment was conducted in a completely randomized design with five replicates. Ten treatments were obtained in a 2x5 factorial scheme, comprising two sources of Li (LiOH - Li hydroxide and Li₂SO₄ - Li sulfate) and five doses (0, 30, 60, 90 and 120?mg kg^?1) in stages V4 and R1. The supply of Li promoted significant effects (p?≤?0.05) on the morphology, yield components and nutritional status of soybean plants. The highest grain yield was obtained with the use of Li₂SO₄ at the estimated dose of 45.7?mg kg^?1. The plants accumulated Li between 8.00 and 11.20?mg kg ^?1, respectively, with the use of Li₂SO₄ and LiOH. In the grains, the highest concentrations of Li were obtained with the application of 120?mg kg^?1. Li₂SO₄ and LiOH are good sources for biofortification of soybean grains.     

YELLOW PASSION FRUIT PLANT NUTRITIONAL DIAGNOSIS AT DIFFERENT PHENOLOGICAL STAGES BY THE DIAGNOSIS AND RECOMMENDATION INTEGRATED SYSTEM METHOD

This work was performed in the Rio de Janeiro State, Brazil, with the objective to evaluate the nutritional status of yellow passion fruit plants along different phenological stages, using the DRIS method. Fifty-four passion fruit cultivated areas with an annual yield productivity ranging from 6.95 to 33.8 t ha^?1 year^?1 and average productivity of 16.9 t ha^?1 year^?1 were selected in the region. The contents of nitrogen (N), phosphorus (P), potassium (K), calcium (Ca), magnesium (Mg), sulfur (S), chlorine (Cl), iron (Fe), zinc (Zn), manganese (Mn), and boron (B) were evaluated. The reference standards were established (mean and variation coefficient) for the values of the nutrient concentration ratios, two by two, on samples from high yield productivity plantations and analyzed by the DRIS index of nutrients for the medium and low yield productivity areas. The established standards differed according with the phenological stage of the culture. In a general way, the mean content of the evaluated nutrients did not differed between the two productivity levels into each phonological stage. There was a difference for the Nutritional Limitation Order between different phenological stages of yellow passion fruit plants. The most negative DRIS indexes and the highest absolute values for the Average Nutritional Balance on yellow passion fruit plants in the region, were found for potassium in May, phosphorus in October and iron in January.     

Influence of phosphorus fertilization on the response of pinus genotypes to glyphosate subdoses

New Forests - Previous studies have reported that phosphorus transporters are involved in glyphosate uptake by plants, so phosphorus fertilization might act as an attenuator of glyphosate effects...     

Constituents of Bowdichia virgilioides

The isolation and (13)C-NMR data of flavone derivatives from Bowdichia virgilioides roots are reported.     

Dynamics and efficacy of sulfentrazone,flumioxazin, and isoxaflutole herbicides applied on eucalyptus harvest residues

New Forests - Eucalyptus harvests generate residues that remain on the soil and affect the efficacy of preemergent herbicides in the following planting cycle. The objective of this work was to...     

Economic viability of Phaseolus vulgaris (BRS Estilo) production in irrigated system in a function of application of leaf boron

Foliar fertilization may be a viable strategy to boron supply in irrigated cropping systems with common beans (Phaseolus vulgaris), since it prevent B leaching. The aim of this work was to evaluate the economic viability and physiological parameters of the common beans production in irrigated cropping systems using sources and increasing foliar boron doses. A field experiment was carried out using an experimental block design in a factorial scheme 2?×?5?×?3, with two sources of B (boric acid and borax) and five doses: 0 (control), 2, 4, 6 e 8?kg?ha^?1, with three repetitions. Foliar B applications were performed at 40 days after seeds germination, in pre-flowering stage. Physiological process (transpiration, stomatal conductance, CO₂ internal concentration, net photosynthesis, and relative chlorophyll index), B level in leaves and grain yield were measured. These data were used to determine the economic viability of B fertilization in common beans. Both boric acid and borax increased B levels in common beans leaves. Borax affected some physiological process reducing stomatal conductance and increasing net photosynthesis. Using borax, the highest net photosynthesis was observed at a rate of 4?kg?ha^?1, while the boric acid increased net photosynthesis linearly after increasing B doses application. An enhance of 311?kg?ha^?1 in the grain yield was observed using borax related to the control (without B application); however, grain yield decreased linearly after application of increasing B doses, as boric acid. Comparing the economic viability of sources and doses of B, the highest profitability is obtained using borax at a rate of 4?kg?ha^?1, which promoting a differential profit of US$534.44 per hectare compared to common beans cropping without B.     

Estimation of natural outcrossing rate and genetic diversity in Lima bean (<Emphasis Type="Italic">Phaseolus lunatus</Emphasis> L. var. <Emphasis Type="Italic">lunatus</Emphasis>) from Brazil using SSR markers: implications for conservation and breeding

Lima bean (Phaseolus lunatus L.) is an important food source in Brazil, especially in the northeast region, where its production and consumption are high. The goals of the present study were to estimate natural outcrossing rates and genetic diversity levels of Lima bean from Brazil, using ten microsatellite loci to obtain information for their conservation and breeding. Fourteen accessions were selected from an experiment in field with open-pollinated and with the presence of pollinating insects. Twelve seeds of each of the 14 selected accessions were grown in screenhouse for tissue harvest and DNA extraction. The multilocus model was used to determine the reproductive system. The outcrossing rate was 38.1 % (t_m = 0.381; t_s = 0.078), and the results indicated a mixed mating system with a predominance of selfing (1 ? t_m = 61.9 %). The biparental inbreeding rate was high (t _m  ? t _s  = 0.303) and the multilocus correlated paternity was quite high (r _p(m) = 0.889), indicating that the progeny was mostly composed of full sibs. The average effective number of pollen donors per maternal plant (N _ep ) was low (1.12), and the fixation index for maternal genotypes (F _m ) was 0.945, indicating that most genitors resulted from inbreeding. The studied families presented considerable genetic variability: A = 6.10;  %P = 30; H _e  = 0.60 and H _o  = 0.077. Total diversity was high (H _T = 0.596), and a portion was distributed within families (H _S = 0.058). In addition, diversity was higher between families (D _ST = 0.538), and genetic differentiation was high (G _ST = 0.902). The results presented here can be used in the implementation of Lima bean conservation and breeding programs in Brazil.