Regina Célia de Matos Pires

The influence of water management and environmental conditions on the chemical composition and beverage quality of coffee beans

The influence of environmental conditions and irrigation on the chemical composition of green coffee beans and the relationship of these parameters to the quality of the beverage were investigated in coffee plantations in the regions of Adamantina, Mococa and Campinas, in the state of Sao Paulo, Brazil. The chemical composition and physical aspects of green coffee beans produced in the three regions were related through Principal Component Analyses (PCA) to the quality of beverage, as determined by sensorial and electronic analyses. The chemical composition was affected by the environmental conditions. Some differences in cup quality were detected by the electronic method but not by cup tasting. Irrigation was not a major factor affecting chemical composition, since there were few differences in relation to non-irrigated coffee plants. The production site appeared to be the main influencing factor on biochemical composition. A pronounced difference was observed in Adamantina, where annual average air temperature was 1.6-2.4oC warmer than in the other two areas and about 3.5oC above to the optimal limit for coffee cultivation.

Estimativa da área foliar de morangueiro

The leaf area index is one of the most utilized physiological parameters employed in plant growth analysis, giving support to interpretation of related yield factors. The aim of this work was to develop a mathematical model suited to estimate strawberry leaflet and leaf areas. The experiment was carried out in Atibaia, SP, during the 1995 season, with the cultivar Campinas (IAC-2712), under open and protected field conditions, in a commercial strawberry growing field. The sampling in each experiment was made up of 25 leaves, with 75 leaflets, including different ages and sizes, picked randomly from 25 plants. Areas were estimated through leaflet width and length measurements, taking in to account the leaflet position on the leaf. Results obtained were fitted to linear models. The leaflet width and length mean was concluded as the best way of predicting area compared to single measurements. The whole trifolioate showed a better leaf area predictive ability than did the central leaflet. Leaf area can therefore be estimated by means of its leaflet width and length measurements, representing a conservative sampling method.

Root-system depth of field beans and wheat under center pivot

O estudo foi realizado na Estacao Experimental de Votuporanga, do Instituto Agronomico, em solo podzolizado com as culturas de feijao e trigo irrigadas por pivo central no inverno de 1989. O objetivo for a determinacao da profundidade efetiva do sistema radicular, como um dos parâmetros fundamentais no manejo das irrigacoes. Estas eram realizadas quando a tensao da agua no solo atingia 0,05 a 0,06 MPa, controlada por tensiometro a 15cm de profundidade. Foram feitas tres medicoes quinzenais de raizes em cada cultura, utilizando-se trado tipo caneca de 7cm de diâmetro. As amostragens foram tomadas na linha de plantio, de 10 em 10cm ate a profundidade de 60cm. Os resultados indicam que, para o manejo adequado da irrigacao, a profundidade do sistema radicular a ser considerada deve ser de 30 e de 40cm, respectivamente, nas culturais de feijao e de trigo no solo em questao.

Cana-de-açúcar fertirrigada com vinhaça e adubos minerais via irrigação por gotejamento subsuperficial: ciclo da cana-planta

This study aimed to evaluate the effect of subsurface drip irrigation and the application of stillage and nutrients in some agronomic parameters, stem yield, technological characteristics of sugarcane and yield of theoretical recoverable sugar. The experiment was carried out in completely randomized block design with four treatments and five replications. The treatments were: mineral fertilizers without irrigation; irrigation and fertigation with NPK using mineral fertilizers; irrigation and fertigation with stillage supplying the K and complementation of N and P with mineral fertilizers; and irrigation and fertigation with stillage supplying the NK and complementation of P with mineral fertilizer. The system of irrigation adopted was the subsurface drip irrigation. The irrigated treatments showed higher number of tillers and leaf area index, when compared to rainfed cultivation. The fertigation with stillage supplying the K promoted higher Brix and stem yield when compared to non-irrigated cultivation. The irrigation and fertigation with stillage supplying the NK promoted higher yield of theoretical recoverable sugar, when compared the cultivation without irrigation.

Irrigation frequency and substrate volume effects in the growth and yield of tomato plants under greenhouse conditions

Tomato cropping (Solanum lycopersicum L.) under protected cultivation using substrates and drip fertigation has improved sustainable production systems especially fruit quality and plant health. However, little is known for tomato plants when considering the interaction between substrate volume and irrigation frequency. The aim of this study was to evaluate the effects of coconut (Cocos nucifera L.) fiber substrate volumes and drip irrigation frequencies on the vegetative growth and fruit yield of tomato plants under greenhouse conditions. The experimental design consisted of randomized blocks arranged in a 3 × 2 factorial with four replicates. Treatments consisted of three substrate volumes (5.0; 7.5 and 10.0 L per plant) and two irrigation frequencies (once and five times per day). Leaf area index tended to increase in plants grown with the largest substrate volume (10 L). Although substrate volumes affected shoot dry matter, no effects on tomato yield and its components were observed. However, plants grown with 5 L of substrate and irrigated once a day produced a greater number of non-marketable fruit due to the higher incidence of calcium deficiency symptoms (blossom end rot). When plants were grown in 5 L or 7.5 L of substrate volume, high irrigation frequency favored the vegetative growth, stomatal conductance, CO2 assimilation and transpiration and fruit yield. Fruit yield and healthy fruits were favored by high irrigation frequency and did not depend on the substrate volume.

Cana-de-açúcar fertirrigada com vinhaça via irrigação por gotejamento subsuperficial em três ciclos de cana-soca

The objective of this study was evaluate the effect of irrigation and fertigation with mineral fertilizer and vinasse applied by subsurface drip irrigation, in the number of tiller, stem yield, technological quality of sugarcane and yield of recoverable sugar in first three cycles of ratoon cane. The treatments were: T1NI - cultivation without irrigation with mineral fertilization; T2I - cultivation fertigated with mineral fertilizers; T3Iv - cultivation fertigated with the vinasse supplying K and complementation of NP with mineral fertilizer; T4IV - cultivation fertigated with the vinasse supplying NPK. In the cycle of the first ratoon cane, there was no effect of treatments on the variables, already in the subsequent cycles, the T2I and T3Iv showed higher numbers of tillers, 17.4 and 17.2 tiller m-1, in the second ratoon cane and 16.6 and 16.0 tiller m-1 in the third ratoon cane, respectively. The stem yield was amended with the T4IV obtaining the higher yield, 179.6 Mg ha-1, in the second ratoon cane, and the T2I and T3Iv in the third ratoon cane, 151.5 and 151.0 Mg ha-1, respectively. There was no treatment effect on the technological quality and in the second ratoon cane the T3Iv and T4IV showed higher yield of sugar, 25 and 25.9 Mg ha-1, respectively.

Distribuição espacial do sistema radicular do cafeeiro fertirrigado por gotejamento em Campinas

Este estudo teve como objetivo avaliar o efeito da fertirrigacao por gotejamento, utilizando-se emissores com diferentes espacamentos (0,50 ou 0,80 m) e profundidades de instalacao (superficial, 0,10 e 0,20 m), na distribuicao espacial do sistema radicular do cafeeiro. Observaram-se no cafeeiro irrigado e adubado de forma convencional diferentes condicoes de desenvolvimento radicular, variando conforme os tratamentos impostos. Para as plantas irrigadas por tubogotejadores com emissores espacados a cada 0,50 m, a profundidade radicular efetiva foi menor (media de 0,63 m) do que a observada para as plantas irrigadas por emissores posicionados a cada 0,80 m (media de 0,70 m). No manejo nutricional por fertirrigacao observou-se menor desigualdade na profundidade radicular efetiva entre os tratamentos, bem como, em um aumento medio de 51,1% de densidade de raizes. Houve tendencia de manutencao do volume radicular na regiao proxima aos emissores, enquanto nos pontos mais distantes do desenvolvimento do bulbo umido, o crescimento radicular foi de 77%. A irrigacao das plantas por tubogotejadores enterrados a 0,10 m de profundidade proporcionou maior desenvolvimento radicular em resposta a fertirrigacao.

Root system distribution of sugarcane irrigated with domestic sewage effluent aplication by subsurface drip system

Irrigation with domestic sewage effluent (DSE) has been recommended by subsurface dripping, as it can obtain a high rate of irrigation efficiency and faster use of salts in comparison with other irrigation methods. The study aimed at evaluating the area, the length and the effective depth of the root system of sugarcane irrigated with DSE by subsurface drip system and with different irrigation rates at depths of 0.00-0.20, 0.20-0.40, 0.40-0.60 and 0.60-0.80m. The experiment was carried out in the municipality of Piracicaba, in the state of Sao Paulo (SP), Brazil, in a sugarcane area irrigated with DSE in a completely randomized blocks set up in furrows, with three replications and four treatments, which are: one area without irrigation (AWI) and three irrigated areas meeting 50% (T50%), 100% (T100%) and 200% (T200%) of the crops water need between each round of irrigation. T100% and T200% provided smaller areas and lengths of roots in the two deepest layers, as compared to AWI and T50%, which stimulated the development of deeper roots due to the water stress. TWI, T100% and T200% presented 80% of the roots up to a depth of 0.40m and T50% treatment presented 76.43% of roots total.

Effect of the water table management in the morpho-physiological adaptation of two wheat species to waterlogging

The effect of three different water table managements in the morpho-physiological adaptation to waterlogging of Triticum aestivum, L. and Triticum durum, L., and the relative influence of the main physical and biological interferance factors were studied. The trial was conducted at ESALQ/USP, Piracicaba, SP, under simulated conditions of a natural low land. After introduction of stress adaptation during the vegetative growth stage, while applying progressive times of hipoxics periods, there were observed different requirements and/or extraction capacities of nutrients between the two species; the fertilization on leaves was not enough to avoid nutritional deficiencies in wheat under hipoxia. The water table management used resulted in morpho-physiological adaptations, but not enough to reach adequate biometric parameters of productivity. The water table at a 15 cm depth throughout the crop cycle resulted in better performance.

Root growth and distribution in sugarcane cultivars fertigated by a subsurface drip system

Despite of the agronomic importance for water management, few studies of sugarcane roots have been performed under field conditions during the crop cycle. The aim of this study was to determine the cumulative root density (LA), root distribution on soil profile and the effective rooting depth (ERD) for three sugarcane cultivars using the minirhizotron method. A field experiment was done with sugarcane cultivars IACSP94-2094, IACSP94-2101 and SP79-1011 grown under subsurface drip fertigation. Soil chemical and physical characteristics were also evaluated. Root evaluations were taken at 38, 58, 123, 185 and 205 days during the second ratoon, considering the soil profile until 0.8 m depth. The highest LA and root growth rates were found up to 0.4 m soil layer for all cultivars. Root growth rate varied during the crop cycle, with the highest values being found between 38 and 58 days after ratoon (DAR). There was a genotypic variation in root growth, with IACSP94-2101 showing the highest LA of 12.9 mm cm–2. The total root length observed around the tube (0.16892 m2) was 10.8, 5.9 and 2.5 m up to 0.8 m depth for IACSP94-2101, SP79-1011 and IACSP94-2094, respectively at 205 DAR. The effective rooting depth varied during the cycle for IACSP94-2094, but all cultivars presented an effective depth of 0.4 m at 205 DAR.