No abstract

Use of trifoliate orange [Poncirus trifoliata (L.) Raf.] as a rootstock has intensified in recent years in Brazil. Objectives of this study were to evaluate the effects of lime and agricultural gypsum on concentration of nutrients in trifoliate orange. Seedlings of trifoliate orange were grown in PVC pipe columns, presenting 15 cm in diameter and 35 cm in length. The columns were sectioned in two rings: the upper ring, 15 cm high, and the lower ring, 20 cm high. The factorial scheme (2×4)+1 was used, being two liming treatments and four agricultural gypsum doses (carried out only in the soil of the upper ring), and an additional treatment (with liming carried out in the soil of both upper and lower ring). Liming increased Mg and S concentrations in roots of the superficial soil layer (0-15 cm). Ca concentration was higher in roots of both superficial (0-15 cm) and subsuperficial (15-35 cm) layers. Gypsum without liming resulted in higher N, K, and Mn concentrations and lower Mg concentration in roots of the soil subsurface layer. Ca and S concentrations in root of the soil superficial layer were higher with gypsum. In plant shoot, the concentrations of K, Ca, S and Cu were higher with liming, and concentrations of Ca and P were higher and lower, respectively, with gypsum application.

Yerba mate (Ilex paraguariensis A. St.-Hil.) is an importance species of the Southern Brazilian silviculture. Besides the traditional ‘terere’ and 'chimarrão' beverage, also called 'mate', its raw material is used in the production of food, beverages, cosmetics, hygiene products and important medicines. Its raw material has been applied in the production of food, beverages, cosmetics, cleaning products and important medicines. Recently there has been an increase in demand for products derived from yerba mate in several countries, such as Italy, Spain and the United States. However, yerba mate crop still suffers some problems, mainly regarding the production of yerba mate seedlings. These, in most cases, are obtained via sexual propagation, which may result in low yield and final product quality, which may lead to decreased profitability for field producers. All of this due to the lack of efficient protocols for clonal propagation of yerba mate, as well as, the knowledge about the factors that interfere in the rooting process, hormonal balance, use of rooting inducers, collection time of propagules, progenitor age, rooting environment, substrates and nutrient solutions. As for the method used to carry out the research, a bibliographic review was used as a tool to investigate the factors influencing the rooting of cuttings and mini-cuttings in yerba mate, addressing scientific data published from 2009 with vegetative propagation by cuttings and mini-cuttings of Ilex paraguariensis. The purpose of this review is to verify the state of the art and the viability of vegetative propagation by cuttings and mini-cuttings of yerba mate.

A qualidade da formação dos pomares de citros está diretamente relacionada ao porta-enxerto utilizado. A espécie Poncirus trifoliata (L.) Raf., conhecida como trifoliata, tem-se mostrado como boa opção de porta-enxerto, sendo usada na região Sul do Brasil. O calcário e o gesso agrícola são os principais insumos usados para manejar a acidez do solo em superfície e subsuperfície, respectivamente, podendo melhorar o desenvolvimento de raízes e parte aérea das plantas. Objetivou-se avaliar o crescimento e produção de matéria seca de raízes e parte aérea em mudas de trifoliata cultivadas sob efeitos da gessagem e calagem. As mudas foram cultivadas em colunas de tubo de PVC (vasos), com 15 cm de diâmetro e 35 cm de altura, seccionadas em dois anéis: o anel superior, 0-15 cm de profundidade, e o anel inferior, 15-35 cm de profundidade. O experimento foi realizado em esquema fatorial (2×4)+1, sendo dois tratamentos de calagem e quatro tratamentos de doses de gesso agrícola, que foram aplicados apenas no solo do anel superior, e um tratamento adicional que recebeu calagem no solo de ambos os anéis, superior e inferior. O delineamento experimental foi em blocos ao acaso com quatros repetições. A calagem e as doses de gesso não afetaram o desenvolvimento da parte aérea das mudas de trifoliata, porém houve maior teor de clorofila aos 55 dias após transplantio com a gessagem sem a calagem. A calagem aumentou a produção de matéria seca de raiz na camada superficial do solo (0-15 cm de profundidade), mostrando a importância da correção da acidez do solo para o desenvolvimento do sistema radicular em mudas de trifoliata.

Gypsum (CaSO4.2H2O) decreases the harmful effect of soil acidity on plants and provides calcium (Ca) and sulfur (S) for plant nutrition. Setaria grass (Setaria anceps Stapf) and black oat (Avena strigosa Schreb.) are forage grasses that are tolerant of low soil fertility and may be suitable as inter-row crops for Satsuma mandarin (Citrus unshiu Marc.) grown organically on Oxisol soils, which may suffer low native fertility and high acidity. We evaluated the effect of gypsum application to a low fertility soil from subtropical Brazil on soil chemical fertility, growth and plant nutrition of Satsuma mandarin, and plant biomass yield and soil nutrient extraction of setaria grass and black oat cultivated between the orchard rows, in the absence of soluble industrial (NPK) fertilisers. The entire experimental field was limed, and ground natural phosphate rock was applied. During planting of the Satsuma mandarin, organic manure and ground natural phosphate rock were mixed with soil and placed in each planting hole. Two agricultural gypsum treatments were applied: one without gypsum (control), and the other with gypsum at 6 tha−1. After 12months, gypsum reduced the level of aluminium (Al3+) and increased Ca2+ at soil depth 0–40cm, and increased S-SO42− at soil depth 0–60cm. Other soil chemical components (pH, phosphorus, potassium, magnesium and micronutrients) were not affected by gypsum application. Gypsum did not affect growth of Satsuma mandarin, but increased leaf S concentration. Between the rows, gypsum decreased nitrogen extraction by setaria grass and increased Ca and S extractions by black oat. Biomass yield and nutrient extraction by the studied forage grasses were satisfactory, considering the poor soil fertility conditions. Setaria grass exhibited higher efficiency in recycling nutrients from the chemically poor soils than black oat. In general, setaria grass and black oat can be used as inter-row forage grasses for organic orchards of Satsuma mandarin, where there are restrictions on use of soluble industrial fertilisers.