Symptoms and interrelationships of macro and micronutrients available for soybean

Nutrients have differences in their functions as metabolic and structural constituents in plant organs. The specific identification of the symptoms of excess or deficiency of nutrients is essential for the correct management to be carried out in order to avoid production losses. In this context, this research aimed to evaluate the symptoms of deficiency and excess of nutrients in soybean. The experiment was carried out on a bench, with 3-liter containers, in which uniformly germinated seedlings were selected for implantation. Initially, the seedlings were subjected to a complete nutrient solution to allow for a uniform and unrestricted initial development over a period of one week. Then, the plants were subjected to solutions with twice as much nutrient, absence of nutrients, complete solution and nutrient restriction, individual omissions resulted in morphological changes, which translated into visual symptoms characteristic of the nutritional deficiency of the respective nutrient. The solution with twice the nutrient concentration of the complete solution showed an increase in the absorption of N, Mg, K and Fe, for Cu it was twice the absorption and for Zn five times more. There was a decrease in the absorption of Ca and Mn and, with that, it is concluded that the availability of twice as many nutrients did not result in double their absorption.

Nutritional and Visual Diagnosis in Broccoli (Brassica oleracea var. italica L.) Plants: Disorders in Physiological Activity, Nutritional Efficiency and Metabolism of Carbohydrates

Information on the nutritional status of plants enables adequate fertilisation management. Thus, the aim of this study was to evaluate how nutritional disorders alter the biological, nutritional and biochemical mechanisms of broccoli (Brassica oleracea var. italica L.) plants grown under greenhouse conditions. A complete nutrient solution and omissions of macronutrients were tested in a completely randomised design with four replicates. Broccoli plants grown with the omission of N and Ca were the first of show deficiency symptoms and the greatest reduction in the net photosynthetic rate and stomatal conductance, with evidently impaired plant growth and biomass. Omissions of macronutrients affected carbohydrate partitioning, and the content of soluble sugars significantly decreased by more 60% in response to Mg omission. With K omission, the contents of soluble sugars and starch increased in broccoli leaves by 40% and 60%, respectively. K transport increased in plants grown without Ca. S translocation decreased with the absence of any macronutrient in the nutrient solution. Deficiencies in the nutrients N, K, and Ca cause the most critical early damage in the photosynthetic apparatus and in the nutritional balance of broccoli plants, so attention should be given to replenishing these nutrients in plantations.

Efecto de enmiendas minerales sobre el contenido mineral y antioxidantes en frutos de frambuesa//Effect of mineral amendments on raspberry fruits mineral content and antioxidants

Con el propósito de que plantas de frambuesa cultivadas en sustrato de peat moss y perlita, adquirieran una mayor cantidad de nutrientes minerales de los que comúnmente obtienen de una solución nutritiva completa en cultivo sin suelo, aquí se reporta el efecto de enriquecer el medio de crecimiento (sustrato) con diferentes moliendas de rocas minerales ricas en nutrientes (roca fosfórica, riolita, diatomita, dolomita, zeolita y harina de basalto) de las cuales se aplicaron 15 g por tratamiento a cada planta de frambuesa (Rubus ideaus L.) variedad fx1522. Con las aplicaciones de las diferentes rocas molidas se incrementó en frutos el contenido mineral de K, P, Ca, Mg, S, y Cu en 27, 27, 42, 33 y 44 %, respectivamente. Con respecto a la actividad enzimática de la catalasa se encontró que con riolita, diatomita y zeolita aumentaron en 54, 45 y 34 % respectivamente comparados con el testigo. La actividad de superóxido dismutasa y el contenido de vitamina C no se vieron afectadas por los tratamientos. El tratamiento con zeolita incrementó los compuestos fenólicos en un 23 %.ABSTRACTIn order for raspberry plants cultivated in an inert growing medium of peat moss and perlite acquire a greater amount of mineral nutrients than they commonly obtain from a complete nutrient solution in soilless culture, here we report the effect of amending the soilless growing medium with different ground mineral rocks (mills) rich in nutrients (phosphate rock, rhyolite, diatomite, dolomite, zeolite and basalt flour) of which 15 g were applied per treatment to each raspberry plant (Rubus ideaus L.) variety fx1522. The applications of different ground rocks increased the fruits K, P, Ca, Mg, S, and Cu mineral contents by 27, 27, 42, 33 and 44 %, respectively. Regarding the CAT enzymatic activity, it was found that the treatments with riolite, diatomite and zeolite increased 54, 45 and 34 % respectively when compared against the control plants. Superoxide dismutase activity and vitamin C content were not altered by the treatments. The treatment with zeolite increased the phenolic compounds by 23%.

Macronutrient Omission Affects the Seedling Performance of Eugenia dysenterica DC., an Important Fruiting Species of the Cerrado Biome

Cagaita (Eugenia dysenterica DC.) seedling production is currently important for the restoration of degraded areas of the Cerrado biome and to supply the demand for its fruits for regional food production. The plants of Cagaita have been described in the literature as resistant to nutrient-poor soils, but the studies remain inconclusive. Therefore, we tested the hypothesis that initial E. dysenterica seedling development could be affected by the lack of specific nutrients. We planted seedlings of this species in complete hydroponic solution and under individual macronutrient omission of N, P, K, Ca, Mg and S. The development of macronutrient deficiency symptoms was visually monitored for 120 days after transplantation in response to the treatment solution, and growth characteristics and tissue contents of different macronutrients were determined. The omissions of Mg and P were the treatments with the strongest effects on seedling growth. The most commonly observed deficiency symptoms were chlorosis and necrosis, in addition to leaf purpling (P deprivation), impaired root hair development (Ca and S deprivation) and a reduced number of leaves (Mg and P deprivation). The macronutrients Ca and N were most accumulated in the shoots and roots of plants subjected to complete nutrient solution, showing the importance of the availability of these nutrients in the initial stages of seedling development for the production of healthy Cagaita plants, with greater viability in the field.

Influence of Arbuscular Mycorrhizal Fungus in the Development of Salicornia in Saline Water

The objective of this work was to evaluate the effect of the inoculation of the arbuscular mycorrhizal fungus (AMF) Claroideoglomus etunicatum on the development of Salicornia ramosissima subjected to five treatments: water, desalinator reject, reject plus one dose (7 g) of NaCl, reject plus two doses of NaCl and reject plus three doses of NaCl. The experiment was conducted under greenhouse conditions at the Agronomic Institute of Pernambuco - IPA, in a completely randomized design, with autoclaved and non-autoclaved soil, with three replications. A dose corresponding to 1.0 mL ̸ kg of Hoagland & Arnon complete nutrient solution soil was added to each well and watered daily with the corresponding treatments. In the conduction of the experiment, polyethylene vessels with 8 kg of saline soil were used. The results showed that the reject with the intermediate doses (Reject + 1NaCl and Reject + 2NaCl) was more significant for the growth (17.16 cm and 17.37 cm respectively) of Salicornia ramosissima.

Analysis of the Atriplex Subjected to Claroideoglomus etunicatum and to the Desalinator Reject

The objective of this work was to analyze the minerals extracted from the soil and absorbed by Atriplex nummularia Lind. submitted to Claroideoglomus etunicatum and to the desalinator reject. The experiment was conducted in a greenhouse at the Agronomic Institute of Pernambuco - IPA, Recife, Pernambuco, Brazil. The experimental design was of randomized blocks with the treatments constituted in a factorial scheme, in five levels of salinity: AC: 2.87 mS / cm; T1: 11.54 mS / cm; T2: 12.04 mS / cm; T3: 13,13 and T4: 14,16 mS / cm, associated with the presence and absence of AMF, presence and absence of nutrient solution and autoclaved and non-autoclaved soil. 8.0 ml of Hoagland & Arnon complete nutrient solution was added every fortnight. After five months, the contents of the elements absorbed by the plant and present in the soil were evaluated. It was observed that in non-autoclaved soil Atriplex absorbed higher nutrient content. Furthermore, the best treatment was the T4 of EC of 14.16 mS/cm + AMF + Hoagland & Arnon solution. Therefore, the high sodium content absorbed (22%) by Atriplex evidences the potential of its use in phytoextraction programs in soils affected by salts.

Mycorrhizal Colonization in Atriplex nummularia Lind. Subjected to Desalinizador Reject

This work has the objective of evaluating the mycorrhizal colonization of Arbuscular Mycorrhizal Fungus - AMF Claroideoglomus etunicatum in Atriplex nummularia Lind. subjected to desalinator reject. The experiment was conducted in a greenhouse at the headquarters of Agronomic Institute of Pernambuco - IPA, Recife, Pernambuco, Brazil. The experimental design was randomized blocks with the treatments constituted in a factorial scheme of five levels of salinity in AC= 2.86 mS/cm; T1= 11.54 mS/cm; T2= 12.04 mS/cm; T3= 13.13 mS/cm and T4= 14.16 mS/cm, associated with the presence and absence of fungus, presence and absence of nutrient solution, and autoclaved and non-autoclaved soil. 8.0 g of Hoagland & Arnon complete nutrient solution was added every fortnight. After five months, the roots of the treatments were collected and the root colonization was evaluated. It was found that in all treatments the association between Claroiodeoglomus etunicatum and Atriplex nummularia was beneficial. The correlation was positive for the treatment T4 (Reject + 14 gNaCl) + AMF. Thus, it was observed that salinity had no negative effect on the association as well as on the growth of the vegetable.

The different response of sugarcane genotypes in multiple stress

ABSTRACT Research focused on identify abiotic stress-tolerant genotypes is highly desirable since their use may reduce costs of soil and crop management and productivity losses. The aim of this study was to determine the behavior of 24 sugarcane genotypes under high levels of Al3+ and Mn2+ associated with low availability of mineral nutrients. The experiment was carried out under greenhouse condition in a 24 × 2 factorial scheme (24 genotypes × 2 treatments: with and without stress), and four replications in completely randomized design. In the treatment without stress plants were grown in a complete nutrient solution whereas in the treatment with stress a nutrient solution with a high acidity (4.0 ± 0.1) and 5% of its original concentration, as well as a high concentration of aluminum (60 mg L-1) and manganese (700 mg L-1) was used. The genotypes RB966928, RB855443, IACSP96-3060, SP81-3250, RB867515, CTC 21, RB965902, and IAC91-1099 had their biometric characteristics less affected by the stress, possibly due to the ability to continue the process of cell division and elongation and to maintain meristematic viable regions, hence they were considered as the most tolerant. On the other hand, the genotypes RB965917, CTC 15, CTC17, RB855536, CTC 2, CTC 20, and CTC99-1906 were the most sensitive to stress. Root system was the most affected by stress, with most genotypes showing more than 70% reduction in root biomass. No relationship was observed between tolerance level of genotypes and the maturation cycles.

Luehea divaricata Martius et Zuccarini Is a Sensitive Species to Aluminum, Not Presenting Phytoremediation Potential

The aim of this work was to evaluate the effect of different concentrations of aluminum (Al) on physiological and biochemical parameters of Luehea divaricata seedlings grown in a hydroponic system under greenhouse conditions to verify the possible tolerance to Al or phytoremediation potential of this species. Seeds of Luehea divaricata were placed to germinate in commercial substrate and after 30 days the seedlings were transferred to a hydroponic system with a complete nutrient solution, pH at 4.5±0.1, with daily adjustment. After 20 days of acclimatization, homogenous plants were selected and transferred to a new nutrient solution (without phosphorus (P) and pH at 4.5±0.1) with different concentrations of Al: 0, 25, 50, 75 and 100 mg L-1, each treatment being composed of 10 replicates of one plant each. The experiment was conducted in a completely randomized design. After seven days of exposure to the treatments, plants were collected for physiological and biochemical analyzes. Aluminum promoted a significant reduction in fresh and dry weight of roots, stems and leaves; in plant height; leaf number; leaf area; and pigment content. On the other hand, Al promoted an increase in lipid peroxidation and guaiacol peroxidase enzyme activity. Therefore, the presence of Al in the growth medium, for the studied conditions, altered significantly both physiological and biochemical parameters in Luehea divaricata seedlings, presenting a sensitive behavior to this element. Due to these characteristics, the studied species does not show phytoremediation potential.

ACCUMULATION AND PARTITION OF Fe, Zn, Cu, Mn AND Na IN MACRO AND MICRONUTRIENT-DEFICIENT COWPEA PLANTS

Cowpea (Vigna unguiculata) is an important crop for people living in the semi-arid tropics where it is used as food, animal feed and forage. Researches related to nutritional status of plants are important, principally in crops commonly grown in nutrient-poor soils. This study aimed to analyze the growth and accumulation/distribution of some micronutrients in cowpea plants submitted to macro and micronutrient deficiency. Cowpea seeds were germinated in grit and after five days, ten uniform seedlings were transferred to complete nutrient solution for an acclimatization period. After three days, the plants were grown in nutrient solution containing all macro and micronutrients or in nutrient solution without N, Ca, K, Mg, P, S, Fe, B or aeration. In all case, omission of mineral nutrients and the aeration caused reductions in the dry mass of cowpea plants, except for B; however, the absence of Ca was the most limiting for plant growth. Interestingly, the root Fe content significantly increased in Mg-, P- and S-deficient plants. Yet, Fe-deficient plants displayed a significant increase in Cu and Mn content, regardless of plant organ. Our data clearly demonstrate that the Ca is the most important nutrient for V. unguiculata growth, followed by N and Fe. The accumulation and partition of Fe, Zn, Cu and Mn in cowpea vary differentially in root, stem and leaf as affected by nutritional deficiency.