9 research outputs found
Foliar silicate fertilization assessment on bean development and its water deficit stress tolerance
Bean’s productivity is below its productive potential, and among the related factors is the sensitivity to water deficiency. Silicate fertilization may aid to better tolerate this abiotic stress. Therefore, this work aims to evaluate the effects of foliar silicon (Si) doses in the development and tolerance of water deficiency for the bean’s cultivation. The experiment was conducted in a greenhouse, with a completely randomized block design in a 6x2 factorial scheme with four repetitions. Six doses of silicon (0; 0.5; 1.0; 1.5; 2.0; 2.5 kg Si ha-1) with and without water deficiency in flowering were used. The pots with a capacity of 2 L were filled with dystrophic Red Argisol, and they were maintained with automatic irrigation. The leaf temperature (TF) was analyzed daily, and at the end of the cycle, the plants’ height, aerial and root fresh and dry matter, the number of grains per plant, the number of grains per pod, the number of pods per plant, pod length, and grain fresh and dry matter were determined. After water deficit stress, the percentage of absolute integrity and relative water capacity were determined. The water condition reflected differences in plant height, grain dry matter, number of grains per plant, pods per plant, and the foliar temperature. The silicon doses did not influence the development and tolerance to water deficit for the bean culture
Climate and phenology of peach (Prunus persica) in the region of the high and middle valley of Uruguai
O consumo de pêssego se expandiu no Brasil durante a última década. A Região do Alto e Médio Vale do Uruguai, RS, apresenta características potencialmente favoráveis ao cultivo do pessegueiro. Ao avaliar a adaptação de uma cultivar de pessegueiro a uma região, é necessário conhecer o clima e a fenologia das plantas, relacionando-a com horas de frio (HF) para saída da endodormência e com graus-dia (GD) para o seu desenvolvimento. O entendimento das relações entre fenologia e meteorologia contribui para melhorar o manejo da cultura. O objetivo deste trabalho foi caracterizar o clima regional e determinar o comportamento do pessegueiro nas condições meteorológicas locais. Para a caracterização climática, sistematizaram-se dados de Iraí, RS e, a partir de uma imagem de altitudes e equações derivadas, produziram-se imagens usando o programa IDRISI. Foram observadas fenologia, fenometria e qualidade de fruto nos anos de 2000 a 2003 e 2005 a 2007, de 18 cultivares. Determinaram-se início e fim de brotação, floração, crescimento e maturação; diâmetro de fruto, firmeza de polpa, sólidos solúveis e acidez titulável. Os dados meteorológicos de precipitação pluvial (PP) foram medidos no local do experimento e os de temperatura do ar, HF (<7, 10, 12 e 15ºC) e GD foram estimados de Iraí e Santo Augusto, RS. Climaticamente a precipitação pluvial mensal variou de 132 a 195mm, com média anual de 1850mm e nas imagens, as HF (<7ºC) variaram entre 94 a 426, com média de 277; o risco de geada foi de 20 a 37%. Para floração, as cultivares Precocinho e Fla foram precoces e as Pilz e Coral e Eldorado, tardias. Nos anos de fenologia, as HF anuais variaram de 156 a 389 (<7ºC) e de 1293 a 1727 (<15ºC). Pela fenologia, determinaram-se às HF e os GD necessários das cultivares. Houve relação positiva entre HF e tempo para brotar e florescer, demonstrando que após sair da endodormência a planta necessita GD para entrar na fase vegetativa. A relação entre nº de dias com PP e duração da floração foi positiva, sugerindo que dias nublados alongam e dias com brilho solar encurtam o período.The consumption of peach increased in Brazil during the last decade. The region of the Region of the High and Middle Valley of Uruguai, in Rio Grande do Sul State (RS), provides favorable characteristics for growing peach. The adaptation of peach cultivar in a certain region has the necessity of knowing the climate conditions and evaluating the plants phenology, in terms of chilling hours (CH) for endormency and degree-days (DD) for the plant development. Understanding the relationship between phenology and weather contributes for facilitating the crop management. This study aimed to characterize the regional climate and to determine the behavior of peach in the local weather conditions. Climatological data from Iraí, RS were systematized for characterizing the regional climate, and with a image of altitudes and derived equations, images were elaborated by using the IDRISI software. Cultivars were described in terms of phenology, fenometry and fruit quality, from 2000 to 2003 and, 2005 to 2007 of 18 cultivars. The beginning and the end of budding, flowering, growth and maturation of fruit, fruit diameter, flesh firmness, soluble solids and titratble acidity were determined. Data of rainfall were measured at the experimental site while the air temperature, CH (below 7, 10, 12 and 15ºC) and DD were estimated from Iraí and Santo Augusto, RS. Climatically the monthly rainfall ranged from 132 to 195mm, with annual average of 1,850mm. In the images generated, the CH (below 7ºC) ranged from 94 to 426, with an average of 277. The risk of frost ranged from 20 to 37%. For flowering, the Precocinho and Fla cultivars were earlier, while cv. Pilz and Coral were later. During the period of phenological observations, the annual CH ranged from 156 to 389 (below 7ºC) and from 1,239 to 1,727 (below 15ºC). The phenology of the studied cultivars, were characterized in terms of CH and DD necessary for each one. A positive relationship between CH and time in days for starting the budding and flowering was observed. This relationship shows that plants has entered into ecodormancy but didn’t have accumulated sufficient DD. A positive relationship between number of rainy days and duration of flowering was detected, suggesting that cloudy days prolong this period, while sunny days reduce the same period
Propagação vegetativa de Platanus acerifolia Ait: (II) efeito da aplicação de zinco, boro e ácido indolbutírico no enraizamento de estacas Vegetative propagation of Platanus acerifolia Ait: (II) effect of zinc,boron, and indolbutiric acid on rooting of cuttings
O objetivo desse trabalho foi avaliar os efeitos da aplicação do zinco (Zn), boro (B) e ácido indolbutírico (AIB) no enraizamento de estacas de Platanus acerifolia Ait. Os tratamentos consistiram do condicionamento das estacas, coletadas em quatro épocas ao longo do ano e representando diferentes tipos fisiológicos, com: sulfato e cloreto de zinco (0, 2,5, 5, 10, 20 e 40mg l-1 Zn), ácido bórico (0, 50, 100, 150, 200 e 250mg l-1 H3BO3) e ácido indolbutírico (0, 20 e 40mg l-1 AIB), através de solução aquosa, pela imersão de 3cm da base da estaca, com duas lesões laterais de 2cm, por 24 horas. A estaquia foi feita em vasos contendo como substrato uma mistura de areia média e casca de arroz carbonizada (1:1, v/v), ambas lavadas. O experimento foi conduzido por 110 dias em casa de vegetação com aspersão intermitente. No encerramento do experimento, avaliaram-se os seguintes parâmetros: comprimento e número de raízes primárias por estaca, máteria seca de raízes por estaca e percentagem de enraizamento. A aplicação isolada de Zn e B não influencia o enraizamento das estacas. O condicionamento de estacas de ramos "do ano" basais finas com AIB afeta, negativamente, o percentual de enraizamento e, positivamente, o número de raízes por estaca.<br>The aim of this work was to evaluate the effects of zinc (Zn), boron (B), and indolbutiric acid (IBA) on rooting of Platanus acerifolia Ait. cuttings. The treatments of the cuttings, which were collected at four different times during the year and representing four physiological types of cuttings, were: zinc sulphate and chloride (0, 2,5, 5, 10, 20, and 40mg l-1 Zn), boric acid (0, 50, 100, 150, 200, and 250mg l-1 H3BO3), and indolbutiric acid (0, 20, and 40mg l-1 IBA). The treatments with B, Zn and IBA were done through submersion of 3cm of the cutting basis, during 24 hours, in an aqueous solution. The cuttings were rooted in pots containing as substrate a mixture of medium sand + carbonised rice husk, 1:1 v/v, both washed. The experiment was conducted during 110 days under intermittent artificial mist conditions. The evaluated parameters were: length and number of primary adventitious roots, dry weight of adventitious roots, and percentage of rooting. The results show that Zn and B have no influence on the rooting, and the addition of IBA on thin basal semi-herbaceous cuttings reduces the percentage of rooting and increase the number of roots
Propagação vegetativa de Platanus AcerIfolia Ait.: (I) efeito de tipos fisiológicos das estacas e épocas de coleta no enraizamento de estacas Vegetative propagation of Platanus AcerIfolia Ait.: (I) effect of physiological types of cuttings and times of the cuttings collection on rooting
O objetivo desse trabalho foi avaliar os efeitos do tipo fisiológico da estaca e da época de coleta no enraizamento de estacas de Platanus acerifolia Ait. Os tratamentos consistiram de uma combinação bifatorial (4 x 4), representados por quatro tipos fisiológicos de estacas de ramos ("de ano", "do ano" basal, "do ano" mediana e "do ano" basal fina) e quatro épocas de coleta (setembro/95, janeiro/96, março/96 e julho/96). A estaquia foi realizada em vasos contendo como substrato uma mistura de areia média e casca de arroz carbonizada (1:1, v/v), ambas lavadas. O experimento foi conduzido por 110 dias em casa de vegetação com sistema de microaspersão intermitente. A melhor época de coleta das estacas para o enraizamento é em julho e as estacas de ramos "do ano" basais apresentam o maior potencial de enraizamento.<br>The aim of this work was to evaluate the effect of the physiological type of the cutting on rooting of Platanus acerifolia Ait. cuttings collected at different times. The treatments followed a 4 x 4 factorial scheme, involving four physiological types of the cuttings (hardwood, basal semi-herbaceous, middle semi-herbaceous, and thin basal semi-herbaceous), and four different times of the cuttings collection (September/95, January/96, March/96, and July/96). The cuttings were rooted in pots containing as substrate a mixture of medium sand + carbonised rice husk, 1:1 v/v, both washed. The experiment was conducted during 110 days under intermittent artificial mist conditions. The results indicate that the best time to collect cuttings to get rooting is in July, and basal semi-herbaceous cutting shows the best percentage on rooting