Transpiration and growth of young African mahogany plants subject to different water regimes.

Timber production has been prominent in the Brazil scenario to minimize deforestation. Thus, technical information is necessary to define the productive process of the African mahogany in the Midwest region of Brazil, especially with regard to its hydric parameters. Recent studies, reported in the literature, have shown that irrigation improves the performance of young African mahogany plants in the field. Sap flow measurement can be used to estimate transpiration of perennial plants and to determine their water demand. This study evaluated the influence of two water regimes on the transpiration and growth of an African mahogany forest after irrigation has ceased. Moreover, this study also characterizes the seasonal patterns of transpiration and growth of African mahogany under these conditions. African mahogany plants with 2.5 years of age were cultivated in Bonfinopolis-GO and evaluated for 2 years. Treatments were IT-irrigated until 2 years of age-and NIT-non-irrigated. Plant height (PH), breast height diameter (DBH), trunk volume (TRV), leaf area (LA), leaf dry matter (LDM), and transpiration (T) were monitored by heat dissipation probe (HDP) between Oct/2014 and Oct/2015. Higher growth in LA, DBH, and LDM were observed in IT. However, increase in PH and TRV was similar in both treatments. The mean annual T was similar between treatments (15.0 L m-2 month-1). The highest T was recorded in October/2014 (IT = 33.0 L m-2 month-1) and July/2015 (NIT = 20.5 L m-2 month-1). The greater LA and water deficit blades DEF > 30 mm promoted lower transpiration in the irrigated plants. Irrigation maintained plant growth in PH, DBH, and LA in the third year, even after irrigation has ceased. However, non-irrigated plants were similar in TRV (0.065 m3) and transpiration rates (≈ 15 L m-2 month-1). Winter transpiration (11.3 L m-2 month-1) was lower than in summer (18.8 L m-2 month-1) for irrigated plants and similar for non-irrigated plants (≈ 14 L m-2 month-1). Based on that, in order to maintain the homogeneity of the plants, the irrigation in the first 2 years of cultivation is recommended, and also, the sap flow measures presented satisfactory results regarding the determinations of the water needs of African mahogany.

Correction to: Transpiration and growth of young African mahogany plants subject to different water regimes.

This original article was erroneously published with the contributor name Ana Cláudia Sérvulo. The publisher and author group of the article would like all to know that the contributor name should instead be presented and be recognized as Ana Cláudia Oliveira Sérvulo and not the former.

Seedling production of Jatropha curcas in substrates fertilized with lithothamnium / Produção de mudas de pinhão manso em substratos adubados com lithothamnium

Seedlings of high quality are essential for the deployment of homogeneous plants. Thus, was evaluated the formation of seedlings of Jatropha (Jatropha curcas L.) in different substrates fertilized with fertilizer-based lithothamnium. It was used substrates I) mixed of: never cultivated soil, cattle manure and sand in proportions: 3:1:1 volume/volume (v/v); II) commercial substrate Tropstrato®; III) cattle manure and carbonized rice straw in proportions: 1:1 (v/v); IV) birds manure, carbonized rice straw and never cultivated soil in proportions: 1:1:4, and V) fine vermiculite. Lithothamnium fertilizer levels used were 0%, 5% and 10% (v/v), respectively. The experimental design used was randomize blocks with factorial of 5x3 (five different substrates and three different lithothamnium doses) and four replication. Lithothamnium doses and substrates influenced the seedling growth of Jatropha. Seedlings fertilized with the substrates soil with mineral fertilizers (substrates 1); compost with manure and carbonized rice hulls (Substrate 3); soil with hatchery compost (Substrate 4) fertilized with a dose of 6.8% (v/v) lithothamnium showed the best result.

A qualidade da muda é fundamental para implantação de lavouras homogêneas. Desta forma, avaliou-se o crescimento de mudas de pinhão manso (Jatropha curcas L.,), em diferentes substratos adubados com fertilizante à base de lithothamnium. Foram utilizados os substratos: I) terra de barranco, esterco bovino curtido e areia nas proporções 3:1:1 volume/volume (v/v), respectivamente; II) substrato comercial denominado Tropstrato®; III) esterco de curral e palha de arroz carbonizada na proporção de 1:1 (v/v); IV) compostagem de incubatório de aves, palha de arroz carbonizada e terra de barranco na proporção 1:1:4; e V) vermiculita pura de granulação fina. As doses do fertilizante à base de lithothamnium utilizadas foram: 0%, 5% e 10% (v/v), respectivamente. O desenho experimental foi o delineamento em blocos casualisados, em esquema bifatorial 5x3 (cinco substratos e três doses de fertilizante) e quatro repetições. Cada unidade experimental (parcela) foi composta por doze mudas. As doses de lithothamnium e os substratos influenciaram o crescimento de mudas de pinhão manso. As mudas produzidas com os substratos composto por terra de barranco, esterco bovino curtido e areia; esterco de curral e palha de arroz carbonizada e Compostagem de incubatório de aves, palha de arroz carbonizada e terra de barranco adubadas com a dose média de 6,8% (v/v) de lithothamnium, apresentaram o melhor resultado.

Rendimento de óleo de sementes de pinhão manso em plantas irrigadas e adubadas / Yield oil of jatropha curcas seeds of trees irrigated and fertilizated

O trabalho teve por objetivo avaliar os efeitos da irrigação e aplicação do fertilizante Organomineral-Marinho + Biotech® (OMM-Tech) sobre o rendimento de óleo de sementes de pinhão manso em Lavras- MG. Utilizou-se delineamento estatístico em blocos casualizados, com parcelas subdivididas contendo três repetições. As parcelas receberam os tratamentos de manejo de água (com e sem irrigação) e as subparcelas foram constituídas por três formas de aplicação do fertilizante OMM-Tech: T1 = Testemunha (S/ OMM-Tech); T2 = via solo (120 kg ha-1 de OMMTech na forma pó); T3 = via foliar (OMM-Tech na forma líquida e na concentração de 5%); T4 = via solo + foliar (60 kg ha-1 de OMM-Tech na forma pó + OMM-Tech na forma líquida na c de 2,5%). O sistema de irrigação utilizado foi o gotejamento, com emissores espaçados a cada 0,50 m. Para avaliar a resposta da cultura utilizaram-se dados referentes ao segundo ano de produção. O tratamento de irrigação produziu efeitos significativos sobre a produtividade de óleo de sementes de pinhão manso, enquanto as diferentes formas de aplicação de OMM-Tech não influenciaram os resultados. O rendimento de óleo de sementes das plantas irrigadas e de sequeiro foram, respectivamente, 34 e 27%.

The purpose of this study was to evaluate the effects of irrigation and application of Organomineral-Marine + Biotech (OMM-Tech) in yield oil of Jatropha curcas seeds. The experiment was conducted in an experimental area located in Federal University of Lavras, Brazil. A randomized block experimental design with subdivided parcels and three replications was used. The parcels received two different water management treatments: irrigated and no irrigated. The sub-plots were submitted to different OMM-Tech fertilizer application methods: T1= control (no OMM-Tech); T2 = soil application (120 kg ha-1 of OMM-Tech in a powder form); T3 = leaf application (OMM-Tech in a liquid form with a 5% concentration); T4 = soil + leaf application (60 kg ha-1 of OMM-Tech in powder form + OMM-Tech in liquid form with a 2.5% concentration). A drip irrigation system with drippers spaced by 0.50 m was used. We evaluated yield oil of seeds in first production year. Jatropha trees irrigated showed a higher seeds oil yield than no irrigated trees. However, fertilization with OMM-Tech no influenced seed oil yield. Seeds oil yield of jatropha trees irrigated was 34%, and no irrigated 27%.

Análise espaço-temporal da evapotranspiração de referência para Minas Gerais / Spatial-time analysis of evapotranspiration reference in the Minas Gerais State, Brazil

Objetivou-se com esta pesquisa, analisar a demanda hídrica em Minas Gerais, representada pela evapotranspiração de referência (ET0), durante o ano. Os valores de ET0 foram estimados pelo método de Penman-Monteith-FAO a partir de dados diários originados de registros de 42 estações climatológicas do Instituto Nacional de Meteorologia (INMET) referentes a um período de 17 anos (1961 a 1978). No geral, os resultados mostraram que a ET0 é bastante variável em Minas Gerais, chegando a apresentar valores médios de 914 até valores de 1.677 mm ano-1. As maiores variações, tanto espaciais como temporais, são registradas no norte do Estado, onde também ocorrem os maiores valores de ET0. O Estado de Minas Gerais apresenta um déficit hídrico anual em aproximadamente 50 por cento de sua área total. Os meses que apresentaram as maiores e menores demandas hídricas no Estado foram janeiro e junho, respectivamente. Em função da nítida distinção que apresentaram os dados de ET0 geoespacializados nas regiões do Estado de Minas Gerais, o conhecimento do correto valor da ET0 em cada localidade trará benefícios aos produtores no manejo da irrigação.

The knowledge of information that expresses the water requirement of the plants is a fundamental issue for the irrigation process. The objective of this research was to analyze the water requirement in Minas Gerais State, Brazil, represented by the evapotranspiration reference (ET0), during the year. The ET0 values were estimated through the Penman-Monteith-FAO method starting from daily data originated by the registration of 42 climatological stations of the Instituto Nacional de Meteorologia (INMET) referring to a period of 17 years (1961 to 1978). In general, the results showed that the evapotranspiration reference is plenty variable in Minas Gerais, reaching medium values from 914 to 1.677 mm year-1. The largest variations, such as spatial and temporal, are registered in the north part of the State, where happen the greatest values of ET0. The Minas Gerais State presents a annual water deficit in approximately 50 percent of its total area. The months that presented the greatest and smallest water requirements in the State were January and June, respectively. According to the clear distinction that presented the data of mapping ET0 in the different regions in the Minas Gerais State, it becames obsvouly that the knowledge of the correct ET0 values in each locality will bring much benefit to farm-producers in the irrigation scheduling.