Vegetative Performance of Two Cultivars and Four Hybrids of Pineapple in Côte d’Ivoire

Since the early 2000s, pineapple from Côte d’Ivoire has suffered a discount in its marketing due to the heterogeneity of the quality of its fruit and the arrival of MD2 on the international market. In order to help pineapple from Côte d'Ivoire once again win back the international market, Ananas comosus hybrids with an early natural coloring have been developed at the CNRA. The agronomic performances of these hybrids were tested at the research station of Anguédédou. Vegetative characteristics such as plant fresh mass, stem fresh and dry mass, number of leaves generated and leaf D fresh mass of these hybrids H1, H2, H3 and H4 were compared to those of cultivars Smooth Cayenne and MD2 at 2, 4 and 6 months. The results obtained showed no statistically significant difference in plant mass between hybrid H4 (2675 g) and cultivars MD2 (2645 g) and Smooth Cayenne (2763 g) after 6 months of planting. The fresh and dry mass of the stems of these three varieties were also statistically identical. Hybrid H4 leaf D fresh mass was very low (55 g) at six months of planting compared to the two cultivars (73 g each). Hybrids H2 and H3 at this same period gave leaf masses of over 80 g. Regarding the characteristics assessed, hybrids H4 and H3 had much more conformity with cultivars Smooth Cayenne and MD2.

Development and production of iceberg lettuce irrigated with magnetically treated water

Irrigated agriculture has become a concern, given the scarcity of freshwater. To reduce its water consumption, new techniques and technologies have been proposed. Based on this, the objective of this work was to evaluate the influence of different soil water tensions at initiation of irrigation with magnetically treated water, on ‘iceberg’ lettuce Lucy Brown (Lactuca Sativa L.) development and production. The experiment was conducted in a greenhouse, using a completely randomized factorial design, to evaluate two water types (magnetically treated water – MW and ordinary water – OW) and four soil water tensions at initiation of irrigation (T1 – 15 kPa, T2 – 25 kPa, T3 – 40 kPa and T4 – 70 kPa), with three replicates. Tensiometers were used to estimate soil water tension. The evaluated parameters were: aerial part fresh and dry total mass; commercial head fresh and dry mass, root fresh and dry mass; stem fresh and dry mass; stem length and diameter; percentage of leaves with tip burn, total and commercial yield; water use efficiency related to total and commercial yield; plant exposed area; and dry matter content. Despite achieving greater water use efficiency, the magnetic treatment may have hindered the removal of water from the soil by the crop, especially at increased soil water tension at initiation of irrigation.

Development of the cultivar xaraés under different concentrations of teak sawdust

Tectona grandis L.f. (Teak) is a highly cultivated forest species in Brazil. When industrially processed, it generates a large amount of sawdust, a waste that has limited reuse and accumulates in the industrial yards. The aim of this study was to evaluate the effect of fresh teakwood sawdust on the development of Urochloa brizantha (Hochst. ex A.Rich.) R.D.Webster cv. Xaraés in a nursery. The treatments consisted of concentrations of 0, 5, 10, 20, 33 and 50% of sawdust, arranged in four randomized blocks in split-plots. At 45, 75 and 120 days, plant heigh (h), average tillers diameter (d), number of live (nll) and dead leaves per plant, fresh and dry mass of shoots and roots, and Dickson's quality index (dqi) were measured. There was a decrease in h growth, d, nll, fresh and dry mass of shoots and roots and in the dqi of the cv. Xaraés as it increased to concentration of wood sawdust in the substrate. This negative effect can be attributed to the high C/N ratio of sawdust (196/1), which influences the decomposition of organic matter. In addition, the possible Teak allelopathic effects, which are the subject of other studies, should be considered. Unlike the other variables, number of live leaves was not influenced by the treatment with 5% sawdust. Teakwood sawdust has negative effects on the U. brizantha cv. Xaraés development.

Emergence and development of Dianthus chinensis and Limonium sinuatum seedlings on commercial substrate

Limonium sinuatum and Dianthus chinensis are plant species of great importance in Brazilian floriculture, being propagated by seed, therefore, the characteristics of the substrates used are respectable in seedlings emergence and development process. Thus, the objective of this research was to evaluate the influence of two commercial substrates on emergence and development of Limonium sinuatum and Dianthus chinensis seedlings. The experiment was conducted in a greenhouse (Pad & Fan type) at São Paulo State University. The treatments were: T1 – Basaplant® and T2 – Tropstrato®, for both species, whose seeds were germinated in expanded polystyrene trays of 128 cells, being eight replicates, containing 8 seeds/replicate. The evaluated traits were: percentage of emergence, emergence speed index, mean emergence time, shoot height, root length and seedlings fresh and dry mass. The substrate characteristics evaluated were: pH, electrical conductivity, macroporosity, microporosity, total porosity, density and water retention capacity. The experimental design was completely randomized, and data were submitted to analysis of variance to Tukey test at 5% to compare the means. The emergence of Limonium sinuatum and Dianthus chinensis were impaired, possibly due to low electrical conductivity provided by substrates. However, Basaplant® substrate favoured the development of evaluated species in relation to aerial part length, root length and total fresh and dry mass, which is recommended for using as substrate for both species.

The Usefulness of Mixtures with Festulolium braunii for the Regeneration of Grassland under Progressive Climate Change

The climate warming and changes in weather patterns in Europe are negatively affecting the structure of grassland swards. The disappearance of valuable forage grasses can be observed. Therefore, in order to keep grassland productivity high, high-yielding grasses of good quality that are resistant to changes in the weather are being sought. At the moment there are few publications which present the long-term influence of changing weather conditions on meadow sward structure and its fodder value. This study aimed to assess the suitability of grass mixtures with Festulolium braunii for grassland renewal by full tillage on organic soil, taking into account atmospheric conditions. The experiments were carried out in the years 2009–2018 on a meadow complex located on organic soil in the Randow river valley, near Ramin (Germany). Grassland restoration was carried out by the method of full cultivation in three experiments with different proportions of Festulolium braunii and Lolium perenne (the existing grassland was eliminated and seeds of a new grass mix were sown). The meadow experiments were established using the method of random blocks in four repetitions Detailed studies included: floristic composition of meadow sward, fresh and dry mass yields, and content of: crude protein, soluble sugars, raw fiber, and net energy NEL (net energy lactation) concentration. Festulolium braunii, Poa pratensis, Dactylis glomerata, and Phleum pratense proved to be more resistant to low temperatures in winter and excess water in spring than Lolium perenne. The largest production potential of fresh and dry mass was found in mixtures with a high content of Festulolium braunii Festulolium braunii tolerates varied and unfavorable weather conditions (frosts during snowless winters, spring frosts and waterlogging, and droughts) very well and provides a stable good quality sward yield (favourably affected the carbohydrate and protein content of the sward). Lolium perenne, on the other hand, decreases its share in the sward under unfavorable weather conditions.

Productive and physiological responses of jambu (Acmella oleracea) under nutrient concentrations in nutrient solution

ABSTRACT In the last years, jambu has become popular and greatly appreciated, due to its remarkable taste. Thus, hydroponically cultivated jambu is promising, since it achieves better yield and production quality. The aim of this study was to evaluate the effect of ionic concentration in nutrient solution on growth, productivity and gas exchange of jambu. The experimental design was completely randomized, with five treatments and four replicates. The treatments consisted of variations of ionic concentration using the nutrient solution proposed by Hoagland & Arnon (25, 50, 75, 100 and 125%). The length of the main stem, stem diameter, number of inflorescence, leaf area, fresh and dry biomass (shoot, root and inflorescence), photosynthesis, stomatal conductance, transpiration, internal CO2 concentration, Ci/Ca ratio and instant carboxylation efficiency were evaluated. Ionic concentrations significantly affected the studied variables, except the stem diameter, the internal CO2 concentration and the Ci/Ca ratio. The number of inflorescences and the leaf area grew linearly with maximum values (37.8 units plant-1 and 1650.8 cm2 plant-1, respectively) obtained in ionic concentration of 125%. Maximum responses were observed for shoot fresh and dry mass (63.9 and 6.9 g plant-1), root fresh and dry mass (16.7 and 2.0 g plant-1) inflorescence fresh and dry mass (11.0 and 1.8 g plant-1), respectively, at ionic concentration of 125%. Liquid photosynthesis, stomatal conductance, transpiration and instant carboxylation efficiency achieved maximum responses of 17.9 µmol CO2 m-2 s-1, 0.3 mol H2O m-2 s-1, 6.3 mmol m-2 s-1 and 0.06 with estimated concentrations of 84, 70, 80 and 83% of ionic strength, respectively. Thus, we concluded that the ionic concentration of 125% is indicated to obtain a greater biomass accumulation.

Iron Toxicity on Germination and Early Growth of Cecropia hololeuca Miq.

O ferro (Fe) é um nutriente essencial para as plantas, sendo insubstituível ao metabolismo. Todavia, o aumento em sua concentração leva ao acúmulo de espécies reativas de oxigênio e estresse oxidativo que resultará em prejuízos aos vegetais. O objetivo deste trabalho foi verificar o efeito de elevadas concentrações de Fe na germinação e desenvolvimento de Cecropia hololeuca Miq. A espécie foi submetida às concentrações de 0,045, 4 e 8mM aplicados na forma de sulfato ferroso e Fe-EDTA. Foram analisadas a porcentagem de germinação, índice de velocidade de germinação, comprimento da parte aérea, radicular, massa fresca e seca. Para a análise de desenvolvimento foi analisado a área folhar o comprimento do caule, comprimento radicular, massa fresca e seca, os pigmentos cloroplastídeos, fluorescência da clorofila, e análise dos teores de elementos via EDS. Foi verificado a atividade enzimática (SOD, CAT, POX). Ambas as fontes de Fe resultaram em danos à germinação e desenvolvimento. O tratamento com Fe-EDTA mostrou efeitos mais significativos na germinação, crescimento aéreo e radicular e biomassa das sementes. O mesmo tratamento se mostrou mais prejudicial nas plântulas jovens com quedas na clorofila a, crescimento radicular, aéreo, área folhar e biomassa. As plântulas expostas ao Fe apresentaram queda no desempenho fotossintético e no teor de cálcio (Ca) folhar. Não foi observado aumento na atividade da CAT e SOD. A POX apresentou elevação quando submetida ao Fe-EDTA 8mM. Tais resultados evidenciam que a espécie C. hololeuca se mostra sensível a toxidez por ferro, acarretando danos ao metabolismo e crescimento inicial. Palavras-chave: Embaúba. Estresse. Metal Pesado. Toxidez. Abstract Iron (Fe) is as an essential nutrient for plants and is irreplaceable in many metabolic processes. However, the increase in its concentration leads to the accumulation of reactive oxygen species and oxidative stress that will result in damage to plant. The objective of this work was to verify the effect of high Fe concentrations on germination and initial development of Cecropia hololeuca Miq. They were submitted to concentrations of 0.045, 4 and 8mM applied as ferrous sulfate and Fe-EDTA. Germination percentage, germination speed index, shoot length and root, fresh and dry mass were analyzed. For the initial developmental the following variables were analyzed: Leaf area, stem length, root length, fresh and dry mass, chloroplast pigments, chlorophyll fluorescence analysis, analysis of element contents via EDS. The activity of enzymes (SOD, CAT, POX) was verified. Both sources of Fe resulted in damage to germination and development. Fe-EDTA treatment showed the most significant negative effects on germination, root and air growth and seed biomass accumulation. The same treatment was more detrimental in the establishment of young seedlings with decreases in chlorophyll a, root growth, aerial growth, leaf area and biomass accumulation. Seedlings exposed to Fe showed a decrease in photosynthetic performance and a decrease in leaf calcium (Ca) content. No increase in CAT and SOD enzymes activity was observed. POX increased its activity when submitted to 8mM Fe-EDTA. These results show that the species C. hololeuca is sensitive when exposed to toxic levels of Fe, causing damage to metabolism and initial growth. Keywords: Embauba. Stress. Heavy Metal. Toxicity.

INFLUÊNCIA DE ADUBOS LÍQUIDOS NA PRODUÇÃO DE ESPIGA DE MILHO VERDE IRRIGADO

Nos últimos anos, os fertilizantes líquidos começaram a ter uma demanda maior no mercado agrícola, contudo ainda se busca melhorar a metodologia de aplicação. Assim, neste trabalho, buscou-se avaliar a eficiência de produtos líquidos via fertirrigação sobre os aspectos de desenvolvimento e de produtividade da cultura do milho verde irrigada por gotejamento. O delineamento experimental foi constituído por 3 modalidades de adubação: Adubação Mineral (padrão da fazenda), adubação líquida com concentração de 50% e 100%, com 4 modelos de adubação em cobertura, a testemunha (padrão da fazenda) e líquido, nas proporções de 50%, 100% e 150%. Foram avaliados diâmetro basal do colmo, altura da planta e da inserção da espiga principal, comprimento da espiga, porcentagem e números de espigas comerciais, massa fresca e seca da planta, massa fresca e seca da espiga. A aplicação dos adubos líquidos por fertirrigação na cultura do milho influenciou positivamente nas características agronômicas e produtividade de massas. THE INFLUENCE OF LIQUID FERTILIZERS OVER IRRIGATED SWEET CORN EAR PRODUCTION ABSTRACT Over the last years, liquid fertilizers have been more demanded in the agricultural market, however, we are still in search of improvements for their applying methodology. Thus, this paper aims at evaluating the effectiveness of liquid products via fertirrigation over the development aspects and productivity when growing drip-irrigated sweet corn. The trial designer comprised 3 fertilization types: Mineral Fertilization (farm standard), 50% and 100% concentrated liquid fertilization, with 4 fertilization types for covering, testimonial (farm standard), and liquid in the proportions 50%, 100%, and 150%. The basal diameter of the reed, as well as the plant height and main ear insertion, percentage and number of commercial corn ears, fresh and dry mass of the plant, fresh and dry mass of the ear. The liquid fertilizer application via fertirrigation in sweet corn crops influenced positively in agronomic characteristics and mass productivity. Keywords: Sandy soil; Zeamays; Nutrients.

Chicken Manure and Phosphorus Influence on Biomass Production and Chemical Composition of the Essential Oil of Ocimum kilimandscharicum

The effects of soil incorporation of five rates of semi-decomposed chicken manure (0, 5, 10, 15 and 20 t ha-1), with and without the addition of phosphorus (200 kg P2O5 ha-1) on biomass production and chemical composition of the essential oil from leaves of African blue basil were evaluated. The experimental design was a randomized complete block design in a 5 × 2 factorial scheme, with four replicates. The first cut of plants was performed at 70 days after transplanting (DAT) and the second at 140 DAT. The addition of 20 t ha-1 of chicken manure to the soil induced increase in plants height, fresh and dry mass production and yield of essential oil. The use of chicken manure induced an increase in camphor content and decreased content of 1,8 cineole. After regrowth, biomass production of African blue basil was higher when compared to the first cut.