Grape Crops Research Articles

Simulation of grape culture irrigation with photovoltaic V-trough pumping systems

In large areas of the Northeast of Brazil, the population is faced with the severe problem of water shortage aggravated with the lack of electric power. However, some places, like the area next to the river São Francisco, near the city of Petrolina, in the state of Pernambuco, have become quite prosperous with the cultivation of grape crops, either for wine production or to be consumed as fruits. Wine exports have grown as an important economic activity in the region. On the other hand, in areas far from the electric network, photovoltaic pumping systems have contributed to the supply of water for local rural communities. Production of fruits, with water supplied by photovoltaic systems, might, then, become a good alternative in terms of local economic activities. The viability of this proposal depends strongly on the market value of the crop. Taking advantage of some significant technical benefits provided by low concentration tracking devices we propose to use those systems to drive local irrigated crops. Among the large family of concentrators available, V-troughs are particularly adequate for photovoltaic applications since, for certain combinations of the concentration ratio (C) and vertex angle (Ψ), they provide a perfectly uniform illumination in the region where the modules are located (absorber region). A drip irrigation system, located in the city of Petrolina, has been simulated and the maximum surface that can be irrigated by a V-trough photovoltaic pumping equipment was estimated by performing a water balance on a monthly basis. With an array of 1.3 kWp it was found that the system is able to irrigate, without deficit, 2.11 ha. A fixed photovoltaic pumping equipment, with the same photovoltaic array, is able to irrigate an area of 1.20 ha. In both cases, the water stored in the soil contributes with an increase of 33% to the irrigated area, as compared to the case where that contribution is not considered.

The trophic diversity of nematode communities in soils treated with vermicompost: The 7th international symposium on earthworm ecology · Cardiff · Wales · 2002

The effects of vermicomposts on plant parasitic, fungivorous and baterivorous nematode populations were investigated in grape (Vitis vinifera) and strawberry (Fragaria ananasa) field crops. Commercially-produced vermicomposts derived from recycled paper, and supermarket food waste were applied to replicated plots at the rates of 2.5 t ha - 1 or 5.0 t ha - 1 for the grape crop and 5.0 t ha - 1 or 10 t ha - 1 for the strawberry crops. All vermicompost treatments were supplemented with inorganic fertilizer to balance the initial availability of macronutrients especially N, to the crop in all plots. After extraction from soil samples in Baermann funnels, nematodes were identified to trophic levels under a stereomicroscope. Soils from all of the vermicompost-treated plots contained smaller populations of plant parasitic nematodes than soil from inorganic fertilizer-treated plots. Conversely, populations of fungivorous nematodes and to lesser extent bacterivorous nematodes increased in the vermicompost-treated plots in comparison with those in plots treated with inorganic fertilizers.

The trophic diversity of nematode communities in soils treated with vermicompostThe 7th international symposium on earthworm ecology · Cardiff · Wales · 2002

Summary The effects of vermicomposts on plant parasitic, fungivorous and baterivorous nematode populations were investigated in grape (Vitis vinifera) and strawberry (Fragaria ananasa) field crops. Commercially-produced vermicomposts derived from recycled paper, and supermarket food waste were applied to replicated plots at the rates of 2.5 t ha–1 or 5.0 t ha–1 for the grape crop and 5.0 t ha–1 or10 t ha–1 for the strawberry crops. All vermicompost treatments were supplemented with inorganic fertilizer to balance the initial availability of macronutrients especially N, to the crop in all plots. After extraction from soil samples in Baermann funnels, nematodes were identified to trophic levels under a stereomicroscope. Soils from all of the vermicompost-treated plots contained smaller populations of plant parasitic nematodes than soil from inorganic fertilizer-treated plots. Conversely, populations of fungivorous nematodes and to lesser extent bacterivorous nematodes increased in the vermicompost-treated plots in comparison with those in plots treated with inorganic fertilizers.

Brotação e produtividade de videiras da cultivar Centennial Seedless (Vitis vinifera L.) tratadas com cianamida hidrogenada na região noroeste do estado de São Paulo

A região Noroeste do Estado de São Paulo apresenta inverno com temperaturas amenas que permite a produção de uvas entre junho e outubro, fora do período de colheita das regiões vitícolas tradicionais. Nestas condições, a brotação da videira é deficiente e desuniforme, o que exige a quebra de dormência com compostos químicos. Neste contexto, um experimento foi conduzido em vinhedo comercial da cultivar Centennial Seedless (Vitis vinifera L.) em que foi estudado o efeito da cianamida hidrogenada em diferentes épocas de aplicação. As videiras foram podadas em 3 datas diferentes (23-03, 05-04 e 20-04-2002), e as seguintes doses de cianamida hidrogenada (H2CN2) foram utilizadas: 0; 0,75; 1,5; 2,25; 3,0 e 3,75%. As variáveis avaliadas foram as seguintes: porcentagem de brotação, porcentagem de ramos após desbrota, número de cachos, massa dos cachos e produção total. Independentemente da dose de cianamida hidrogenada, as videiras podadas mais cedo apresentaram menor porcentagem de brotação. Aplicações de cinamida hidrogenada apresentaram efeito quadrático sobre a porcentagem de brotação e o número de cachos. Além disso, verificou-se efeito quadrádico das aplicações de cianamida hidrogenada para porcentagem de ramos desenvolvidos, massa dos cachos e produção total, na poda realizada em 20 de abril. Para a poda realizada em 05 de abril, observou-se aumento linear para estas variáveis. A dose de cianamida hidrogenada estimada para a maior porcentagem de brotação foi de 2,89%.

Aptidão agroclimática da cultura da videira no Estado da Bahia, Brasil

Para delimitação das áreas com diferentes aptidões agroclimáticas para o cultivo da videira (Vitis vinifera L.) no Estado da Bahia, Brasil, foram utilizados índices baseados no balanço hídrico climático e nas temperaturas médias do ar. Inicialmente calcularam-se os balanços hídricos pelo método de "Thornthwaite & Mather-1955", utilizando-se 120 mm de retenção de água no solo, com dados climatológicos das regiões de dispersão natural e de cultivo comercial da espécie. Com os dados desses balanços, determinou-se o índice hídrico anual de Thornthwaite (Ih), caracterizando-se o grau de umidade ideal do clima para a cultura. Posteriormente, utilizando-se os valores de temperatura do ar e de precipitação pluvial mensais de 408 localidades do Estado, calcularam-se os balanços hídricos para a mesma capacidade de armazenamento de água no solo e se constatou que não há limitação térmica para o cultivo da espécie na Bahia, sendo os maiores teores de açúcar obtidos nos locais com temperaturas mais elevadas. Portanto, as zonas com aptidão plena foram subdivididas de acordo com os valores de temperatura média do mês mais quente (Tq) de cada local considerado. A sobreposição das isolinhas de Tq e Ih, no Estado resultou em quatro classes de aptidão agroclimática.

Occurence of thrips on Niagara table grape and its control with the insecticides thiacloprid and methiocarb associated with Metarhizium anisopliae

Thrips are reported as important pests on table grapes in United States and several countries of Europe. Damage caused by thrips, particulary Frankliniella occidentalis, was observed on niagara table grape crop in Limeira-SP, Brazil. During the blooming period, high thrips densities were observed feeding on pollen and small berries. The symptoms left were more visible after the development of the berries and were characterized by dark scars and suberized surface on berries, sometimes causing the berry to crack, and the seed to prolapse. The effect of insecticides thiacloprid or methiocarb, associated or not with the entomopathogenic fungus Metarhizium anisopliae were evaluated during the blooming period. For evaluation of thrips damage on fruits, the treatments were applied three additional times, 7, 14 and 21 days after the first application. The treatments were: a) M. anisopliae (strain 1037) 1x10(7) conidia/mL; b) thiacloprid 20mL/100L; c-d) methiocarb 100 and 150mL/100L; e) methiocarb 100mL/100L + M. anisopliae 1x10(7) conidia/mL. Only methiocarb, associated or not with the fungus, was effective in reducing thrips infestation, and no phytotoxic damage was observed. The efficiency of methiocarb 150mL/100L and the insecticide associated with the fungus for the control of the thrips population was 84.2 and 95.5%, respectively. In both cases, there was a reduction of approximately 70% in the number of berries with scars symptoms. For control of thrips on table grapes, chemical insecticides associated or not with M. anisopliae should be applied during the blooming period of the crop.

Grape Growing and Winemaking in Tropical Brazil

Abstract Good quality wine grapes are grown in tropical Brazil. The area is situated around the 9th southern latitude between the cities of Casa Nova, State of Bahia and Santa Maria da Boa Vista, State of Pernambuco, in the Sao Francisco river valley at an altitude of 375 m. The climate is semi-arid, with precipitation of 300-600 mm, and average temperature is 26°C. Grapes are harvested in July and August after 120-130 days of vegetation and again in late December after 100 days vegetation. Grapevines receive one month rest after harvest and are induced to grow again so that the harvest is staggered. Each plant is irrigated with 40 to 80 L of water daily. The quality of wine produced from these grapes is good and is comparable to wines produced in temperate climates. This article details the wine quality parameters and chemical analyses of wines made from several cultivars of grapes in this area. Tropical climates offer possibility of more than one grape crop per year and are therefore attractive for wine...

Dried Grapes: A Case Study in EC Market Disruption

As a result of a badly conceived farm policy the bulk of the EC′s dried grape crop of 1981/82 was sold into intervention. Minimum import prices (MIPs) were introduced, throwing the import trade into confusion, and distorting the market for dried grapes. MIPs meant that the competitive advantage of low cost suppliers was lost, and the importer′s traditional skills of buying cheap were thwarted. Failure to distinguish between types of product, quality and presentation, led to further difficulties. Even marginal failure to respect the MIP led to the application of substantial countervailing charges. In February 1988 a ruling of the European Court gave some relief to the beleaguered trade.

Ocorrência de Eurhizococcus brasiliensis (Hempel) (homoptera: margarodidae) em videira no município de Louveira, Estado de São Paulo

Em 1986, em inspeção em vinhedos no município de Louveira, SP, foi observado definhamento acentuado de plantas em uma quadra de uma propriedade no Bairro de Abadia. Plantas do mesmo vinhedo, mas de outros talhões e de outras propriedades, não apresentava o problema. O exame do sistema radicular de plantas da quadra em questão revelou a presença de Eurhizococcus brasiliensis (Hempel) (Homoptera: Margarodidae) em alta infestação. Conhecida também como pérola-da-terra ou margarodes, é praga muito nociva à videira e de difícil controle. Sua ocorrência no Estado de São Paulo infestando raízes de videira restringia-se aos municípios de São Miguel Arcanjo e Guareí, acrescentando-se, agora, Louveira.

A possible method of protecting grape crops by using an acoustical device to interfere with communication calls of Silvereyes

A possible method of protecting grape crops by using an acoustical device to interfere with communication calls of Silvereyes

Predicting Harvest Date of the ‘Concord’ Grape Crop in Southwest Michigan1

Abstract Modified heat-unit methods, at base temperature 50°F (10°C), were developed that quite accurately forecast the Optimum maturity date for commercial crop harvest of the ‘Concord’ grape (Vitis labrusca L.) in southwest Michigan. Optimum maturity was reached 85 days (SD=4.33) after the date when 1000 units were accumulated for the season and 63 days (SD=4.18) after the date when 1500 units were accumulated. Counting of seasonal accumulation of heat units started April 1. These methods were found to be more accurate than counting days from full bloom to harvest It appears that maturation is determined to a large degree by temperatures during the first 100 days of the season.

Bionomics of a Grape Boring Plume Moth (Oxyptilus regulus, Meyr.) in South India

The grape vine (Vitis vinifera), which is a common fruit crop grown extensively in Mysore, has not been noticed till now to be subject to any very serious insect pests, though one occasionally comes across a Chrysomelid beetle (Scelodonta strigicoUis, Mot.), stray leaf-eating cockchafers (Adoretus spp.), twig-girdling Longicorn beetles (Sthenias grisator, F.), and stray scale-insects, which, however, have not done any very serious damage so far ; but recently substantial damage has been caused to the grape vine crop by an insect which appears to be quite a new record—at any rate for S. India. The insect concerned is a species of plume moth (Oxyptilus regulus, Meyr.), the larva of which bores into the ripening berries of the grape bunches and causes substantial injury. The grapes grown in the Mysore State belong to a local black variety, the fruits of which have a sub-acid taste and do not therefore fetch good prices at present because of the very large imports of sweet varieties from North India and elsewhere. The serious nature of the damage done by this new pest and the consequent menace to the grape crop, which is one of the oldest of the fruit plants to be raised in the State, and the likelihood of the insect extending its activities to the different varieties of this crop cultivated outside the State, prompted the author to attempt a fairly thorough study of the insect with a view to adopting control measures.