Carlos Reisser Júnior

Crescimento de cultivares de alface conduzidas em estufa e a campo

The growth of lettuce cvs. Veronica, Marisa and Regina was analised through an experiment carried out under plastic greenhouse and under field conditions, from April 15th to June 03rd 1999, in Eldorado do Sul, Rio Grande do Sul State, Brazil. Sampling of plants started one week after transplanting and proceeded until the end of the plant cycle on a weekly basis. The lettuce cultivated under greenhouse presented more fresh and dry mass, leaf area, specific leaf area and greater number of leaves. In addition, plants cultivated under greenhouse presented a shorter cycle when compared to the plants cultivated in field conditions. The cvs. did not show any difference when cultivated under greenhouse environment, but, in field conditions, the cv. Regina presented a larger number of leaves and a larger leaf area index than the cultivars Marisa and Veronica.

Desempenho de quatro cultivares de morangueiro em duas regiões ecoclimáticas do Rio Grande do Sul

The choice of cultivars has important significance in achieving success in strawberries cultivation. However, the experiments with cultivars are usually carried out in conventional systems of production and not in soilless growing systems. Due to this, the present research intended to assess the performance of some strawberry cultivars in soilless growing system, inside the greenhouse, in two regions with different ecoclimatic conditions, in Eldorado do Sul (Depressao Central) and Caxias do Sul (Serra do Nordeste), in Rio Grande do Sul State. Four strawberry cultivars were tested: Aromas, Camarosa, Oso Grande and Tudla. The planting was in May 2005, and the seedlings were placed in bags containing substrate composed of 50% of peat and 50% charred rice hulls. The fertilizer was supplied by fertirrigation. Fruits were harvested when 70% of them presented red color up to fully mature. The results showed that the cultivation of strawberries in this system led to lower yield per plant than in a traditional system, but provides better use of internal greenhouse, with positive consequences in yield per area, due to the high density of plants and the facility to manage the crop. The highest productivity was obtained in Caxias do Sul (235.8 g plant-1) compared to Eldorado do Sul (196.4 g plant-1) without interaction between locations and cultivars. In Caxias do Sul, the cultivars Aromas, Oso Grande and Camarosa presented highest yield when compared to Tudla, but there was no difference in Eldorado do Sul.

CARBOHYDRATE CONTENT AND DEVELOPMENT OF STRAWBERRY TRANSPLANTS FROM RIO GRANDE DO SUL AND IMPORTED

A obtencao de elevadas producoes na cultura do morangueiro e dependente da utilizacao de mudas com elevada qualidade sanitaria e fisiologica. Assim, o presente estudo teve como objetivo avaliar a influencia do local de origem das mudas de morangueiro, na qualidade, conteudo de carboidratos e posterior desenvolvimento e producao a campo. Os tratamentos abrangeram quatro origens das mudas: Argentina, Chile, Chui (Rio Grande do Sul, Brasil) e Sao Francisco de Paula (Rio Grande do Sul, Brasil) e duas cultivares (Camarosa e Camino Real), em delineamento experimental de blocos ao acaso, com quatro repeticoes, conduzido no periodo entre abril e dezembro de 2010. Avaliaram-se o conteudo de carboidratos na coroa e nas raizes, o crescimento e o desenvolvimento das mudas e a producao das plantas. Independentemente da cultivar e da origem da muda, os valores de diâmetro da coroa foram superiores a 8 mm, considerado o padrao minimo estabelecido internacionalmente. Mudas propagadas no Chui apresentaram 100% de mortalidade aos 20 dias apos o plantio, enquanto nao foram registradas perdas nas argentinas e chilenas. Mudas de ‘Camarosa’, provenientes do Chile, apresentaram maior conteudo de acucares soluveis totais nos orgaos de reserva, enquanto maior teor de amido foi obtido em mudas argentinas. O maior conteudo de carboidratos nos orgaos de reserva, em mudas argentinas e chilenas, reverteu em maior producao de frutas.

Quebra de dormência e cultivo protegidona produção de plantas de mirtileiro

O objetivo deste trabalho foi avaliar o efeito da epoca de aplicacao da cianamida hidrogenada (CH) em tunel baixo e campo aberto, na producao e no desenvolvimento de plantas de mirtileiro. O experimento consistiu na aplicacao de cianamida hidrogenada em quatro epocas (29-06-12, 09-07-12, 19-07-12, 30-07-12) e dois sistemas de cultivo (tunel baixo e campo aberto), alem de um tratamento adicional ou testemunha (sem aplicacao de CH). O delineamento experimental foi em blocos ao acaso, com tres repeticoes, sendo a cultivar utilizada a Powderblue. As variaveis analisadas foram: inicio da floracao, porcentagem de brotacao, comprimento de ramo, massa seca das folhas, teor de clorofila, producao, massa media de frutos, diâmetro medio de frutos, solidos soluveis. A aplicacao de CH em 29-06 e 09-07 antecipou a floracao e a producao. Ja a brotacao foi antecipada quando a CH foi aplicada em 09-07 e 19-07. Em relacao aos sistemas de cultivo, observou-se que o tunel baixo antecipou a floracao e aumentou a producao. Conclui-se que a aplicacao de cianamida hidrogenada, no final de junho/inicio de julho, antecipa o inicio da floracao, da brotacao e da producao, bem como o uso do tunel baixo que antecipa a floracao e aumenta a producao.

Multivariate analysis applied to the study of the relationship between soil and plant properties in a peach orchard

In the State of Rio Grande do Sul, the municipality of Pelotas is responsible for 90 % of peach production due to its suitable climate and soil conditions. However, there is the need for new studies that aim at improved fruit quality and increased yield. The aim of this study was to evaluate the relationship that exists between soil physical properties and properties in the peach plant in the years 2010 and 2011 by the technique of multivariate canonical correlation. The experiment was conducted in a peach orchard located in the municipality of Morro Redondo, RS, Brazil, where an experimental grid of 101 plants was established. In a trench dug beside each one of the 101 plants, soil samples were collected to determine silt, clay, and sand contents, soil density, total porosity, macroporosity, microporosity, and volumetric water content in the 0.00-0.10 and 0.10-0.20 m layers, as well as the depth of the A horizon. In each plant and in each year, the following properties were assessed: trunk diameter, fruit size and number of fruits per plant, average weight of the fruit per plant, fruit pulp firmness, Brix content, and yield from the orchard. Exploratory analysis of the data was undertaken by descriptive statistics, and the relationships between the physical properties of the soil and of the plant were assessed by canonical correlation analysis. The results showed that the clay and microporosity variables were those that exhibited the highest coefficients of canonical cross-loading with the plant properties in the soil layers assessed, and that the variable of mean weight of the fruit per plant was that which had the highest coefficients of canonical loading within the plant group for the two years assessed.

Water potential in peach branches as a function of soil water storage and evaporative demand of the atmosphere

1Part of Master’s Dissertation of the first author. 2PhD student, no PPG-Management and Conservation of Soil and Water (MACSA), Universidade Federal de Pelotas, Pelotas RS, FAPEG Scholar. Email: alexbeckermonteiro@gmail.com 3Researcher at EMBRAPA Clima Temperado, Pelotas RS. Email: carlos.reisser@embrapa.br 4PhD student at PPG-Management and Conservation of Soil and Water (MACSA), Universidade Federal de Pelotas, Pelotas RS. Email: luciano.romano@cas. ifmt.edu.br 5Associate Professor III, Departamento de Engenharia Rural, Universidade Federal de Pelotas, Pelotas RS. Email: lctimm@ufpel.edu.br 6Professor, Universidade Federal do Pampa, Campus Itaqui RS. Email: m.toebe@gmail.com Abstract-The use of water potential indicators in the plant has been adopted in irrigation management, in recent years, since it is accepted that the plant is the best indicator of its own water status. The objective of this study was to verify the relationship between water potential in peach tree branches and the evaporative demand of the atmosphere and the water availability in two textural classes of an Aquertic Hapludalf soil, aiming to adopt irrigation management strategies based on the water potential in the plant. Research was carried out in a commercial peach orchard, cv. Esmeralda, in the municipality of Morro Redondo-Rio Grande do Sul state, Brazil. Four peach tree rows were evaluated, being two irrigated and two non irrigated. The irrigation management was based on the replacement of the potential crop evapotranspiration. It was concluded that the water potential in the peach tree branch is positively related with the evaporative demand of the atmosphere and negatively related with soil water storage. Future studies should adopt irrigation management strategies for peach trees based on the water potential mainly for the irrigation management of post-harvest peach trees.