Paulo Sérgio de Souza

Épocas de florescimento e colheita da nogueira-macadâmia para áreas cafeícolasda regiäo sudeste

O cultivo da nogueira-macadâmia e rentavel economicamente e consiste em uma opcao para a arborizacao do cafeeiro em diversas regioes; entretanto, a unica restricao de manejo e que as datas de colheita do cafe nao coincidam com as da macadâmia. O objetivo do trabalho e estimar as provaveis datas de florescimento e da queda natural dos frutos (colheita) para varias localidades que apresentam o cultivo do cafe nas regioes da Zona da Mata e sul de Minas Gerais, leste de Sao Paulo e sul do Espirito Santo. Foram utilizadas series historicas de dados de temperatura maxima e minima do ar (oC) e a precipitacao (mm) de estacoes meteorologicas da regiao Sudeste que apresentam o cultivo cafeeiro e que sao aptas climaticamente para a nogueira-macadâmia. Utilizando dados medios mensais de temperatura do ar e total pluviometrico, foram calculados a evapotranspiracao potencial e os balancos hidricos sequenciais, alem do somatorio dos graus-dia para todas as localidades. As melhores datas de colheita da nogueira-macadâmia foram determinadas em funcao dos periodos que evitam as datas de colheita dos cafeeiros e tambem as epocas em que ha ocorrencia de precipitacoes (> 10 mm). As localidades com maior precocidade foram Sao Mateus - ES, e Vitoria - ES, e as tardias foram Barbacena - MG, Caldas -MG, e Campos do Jordao - SP. Para todas as localidades analisadas, nao houve problema na utilizacao da nogueira-macadâmia como arborizacao, visto que a colheita nao ocorre ao mesmo tempo do cafe, exceto em Campos do Jordao. Eventuais precipitacoes podem ocorrer durante a colheita e atrapalhar o processo.

Temperatura do ar em sistemas de produção de café arábica em monocultivo e arborizados com seringueira e coqueiro-anão na região de Mococa, SP

The technique of arborized coffee crops attemp to minimize the extreme meteorological conditions improving the crop development and yield. This work aimed to characterize the air temperature in arborized systems compared to unshaded cultivation. Evaluations were accomplished in a field experiment, implanted in 1999 at Mococa, one of the most important coffee producing areas at State of Sao Paulo, Brazil. The experimental plot had 1600 m 2 , where the coffee plants, cv. Icatu Vermelho IAC 4045, were cultivated in unshaded and arborized systems with rubber tree (16x16m) and dwarf coconut palm (8X8m). The air temperature measurements were made during 2006/07 and 2007/08 crop production years. The treatment with rubber tree reduced the daily maximum air temperature up to 3 °C, especially during summer and spring seasons. In cloudy days there were no differences among treatments with rubber tree and dwarf coconut palm tree and unshaded system. Higher values of daily air temperature amplitude were observed in unshaded coffee treatment. The arborized systems minimize the extreme low temperature effect as they raise the minimum air temperature up to 2 o C.

Variação sazonal do potencial da água nas folhas de cafeeiro em Mococa, SP

In order to assess the xylem water potential in Coffea arabica L. plants, a field experiment was carried out in Mococa, Sao Paulo State, Brazil, from August 2005 to July 2006 with the following cultivars: Mundo Novo (MN), Obata (OB) and Ouro-Verde (OV). The OB and OV cultivars were eight years old, and MN plants had been topped five years ago. Spacing among the plants were 3.6 x 1.0 m, 2.5 x 1.0 m and 3.5 x 0.75 m, respectively. Predawn leaf water potential (ψam) was measured each 15 days. Xylem water potential along the day (ψa) was measured at the end of April. Data concerning leaf ψam varied according to the soil water profile as affect by seasonal rainfall. ψam values were -1.29, -1.60 and -1.68 MPa during dry months and -0.06, -0.07 and -0.07 MPa during months of greater precipitations for MN, OB and OV, respectively. These values were important and relevant to Arabic coffee cultivars in order to characterize plant water status along the year, because the period of water stress was coincident with the phase of induction (February at June) and maturation of flowering buds; and the period of greater rainfall with the phase of grain filling and fruit maturation.

Influencia das condições climáticas na produtividade e qualidade do cafeeiro produzido na região do Sul de Minas Gerais

Coffee is one of the main Brazilian export products and few studies dealing the climate influence on the yield and quality of coffee are found. This study aimed this word evaluate the climatic influence on yield and quality of coffee produced in crops with and without irrigation at different ages in southern Minas Gerais. The treatments consisted of the combination of ages of crops (2, 3 and 8 years) and water irrigation (with and without irrigation), totaling 6 treatments. The experiment was conducted in randomized blocks in the agricultural year 2014 in Muzambinho, Minas Gerais, Brazil. We evaluated the components of yield and quality of the coffee. The weather conditions during the year 2014 were atypical for the region. The coffee crop under rainfed conditions with 2 years has shown greater number of defects and fruit floats and lower density and grain yield. The hydric deficit and the air temperature were the meteorological elements with the greatest influence on yield of coffee. The weather conditions atypical not affect the quality of beverage and granulometric characteristics of coffee crops.

NONLINEAR AGROMETEOROLOGICAL MODELS FOR ESTIMATING LYCHEE FRUIT GROWTH

AbSTRACT - The influence of climate on the development of lychee fruit is complex, but few studies have discussed the problem. We developed agrometeorological models for simulating the development of fruit fresh matter (FM), fruit dry matter (DM), fruit length (LE), fruit diameter (DI), fruit volume (VO), and fruit number per cluster (FN) of the “Bengal” lychee cultivar as functions of climatic conditions. We conducted three analyses: (a) the influence of mean meteorological elements on the rates of fruit growth, (b) estimation of fruit development by the agrometeorological models using sigmoidal adjustments, and (c) simulation of fruit development using multiple nonlinear regression of two meteorological elements to improve the accuracy. A rate of water deficit (WD) near 5 mm d -1 maximised FM, DM, LE, DI, and VO. Increases in potential evapotranspiration (PET), degree days (DD), and actual evapotranspiration (AET) were correlated with increases in VO and decreases in LE and NF. Models estimating fruit development indicated that the accumulation of WD, PET, AET, and DD had sigmoidal relationships with all variables of fruit growth except FN. FN decreased as WD, PET, AET, and DD increased. The adjusted multivariate models were accurate, with the largest error of 6.45 cm

Caracterização e avaliação de frutos de aceroleira

Este trabalho teve por objetivo avaliar caracteristicas fisicas e quimicas em aceroleiras provenientes de seis plantas encontradas no IFSULDEMINAS - Câmpus Muzambinho-MG, para identificar plantas com melhores qualidades geneticas. Foram selecionadas seis plantas de acerolas, e os frutos foram colhidos em quatro epocas. Em cada planta, foi feita uma amostragem com tres repeticoes, por epoca, sendo cada repeticao composta por 10 frutos. Foram realizadas as seguintes analises fisicas: massa fresca, coloracao, diâmetros longitudinal (DL) e transversal (DT), relacao DL/DT, e quimicas: teor de solidos soluveis (SS), acidez titulavel (AT), relacao SS/AT, pH e teor de acido ascorbico. As medias dos tratamentos, quando significativas, foram comparadas pelo teste de Tukey, a 5% de probabilidade. Os resultados medios de massa por fruto variam de 4,03 a 7,10 g, ja as medias do indice de formato do fruto variam de 0,84 a 0,92, constatando-se que o fruto e uma drupa subglobosa. Os diâmetros transversal e longitudinal oscilam, respectivamente, de 16,67 a 23,86 mm e 15,39 a 20,06 mm, e a coloracao da casca foi mais vermelha nas acerolas oriundas da planta 1. Os teores de solidos soluveis variam de 5,48 a 7,90oBrix e, na relacao SS/AT, houve variacao de 5,92 a 8,31. O pH variou de 3,54 a 3,76, a acidez total titulavel de 0,70 a 1,14 g.100 g-1 e os teores de acido ascorbico variaram de 1.114,07 a 1.456,22 mg.100 g-1. Observou-se que, de acordo com as caracteristicas fisicas, a planta 6 apresentou-se mais adequada para uma futura propagacao. Em relacao as variaveis quimicas avaliadas, as acerolas oriundas da planta 1 apresentaram bons teores de acido ascorbico e boa relacao SS/AT, atendendo ao indicado para o suco de acerola.