Ivar Antonio Sartori

Anelamento e incisão anelar em fruteiras de caroço

Growing peaches is of high economic importance in South of Brazil and the State of Rio Grande do Sul is the biggest brazilian producer. Largest part of the orchards are located in the Southern half. One of the main problems of peach production for fresh consumption in this area is the reduced size of the fruits. Another problem is the short harvesting window, which brings difficulties to commercialization. Girdling and/or ringing of branches might be used to increase fruti size and eventually extend the harvesting period. The present review intends to gather data regarding the most adequate period to apply treatments, to understand the physiological aspects and problems associated with these practices on stone fruit trees. Girdling and ringing of stone fruit trees might be useful to improve quality and anticipate harvest period of early ripening cultivars. It is necessary to conduct local studies for different species and cultivars. Recomendations should be specific for each situation and girdling and ringing together with other pratices to induce early ripening might help to anticipate harvest and ameliorate organoleptic of the fruit.

Efeito da aplicação de cianamida hidrogenada e óleo mineral na quebra de dormência e producão do pessegueiro-'Flamecrest'

With the objective of increasing yields and fruit quality of cv. Flamecrest peaches, a cultivar with high chilling units demand, the present experiment was conducted in an orchard near to the Farroupilha city, in the year 2000. The hidrogen cyanamid and mineral oil were applied in two different times: middle of July and begining of August. The Dormancy breaking, flowering, fruit set, yield, and antecipation of harvest were evaluated from plants of the folllowing treatments: 1,22; 2,45; 3,675 or 4,90 g of i.a.L -1 hydrogen cyanamid together with 10 g i.a L -1 of mineral oil or a single application of 10 g i.a L -1 mineral oil. The Control plants were not sprayed with the dormancy breaking treatment. None of the treatments resulted in sprouting antecipation of flowering buds however, plants treated with 1,22 or 4,90 g i.a L -1 hydrogen cyanamid mixed with 10 g i.a L -1 mineral oil, had a higher number of sprouted vegetative buds. There was no significant effect of the period of application on flowering and fruit set. The number of fruits thinned out from each plant was higher for the treatments with 2,45 or 4,90 g i.a L -1 of hydrogen cyanamid mixed with 10 g i.a L -1 of mineral oil. When applied to peaches trees in july, the treatments with 1,22 and 3,675 g i.a. L -1 of hydragen cyanamid and 10 g i.a. L -1 of mineral oil resulted in a higher number of fruits and total yield per plant. All the treatments, in the second apllication period, produced higher yields. The Average fruit weight, total soluble solids and pulp firmness were not influenced by the treatments.

Produção de frutos e incidência de cancro cítrico em laranjeiras "Monte Parnaso" enxertadas sobre sete porta-enxertos

Citrus rootstocks can exert some influences on fruit production and susceptibility of the plants to citrus canker (CC). This research was performed aiming to select rootstocks which induce higher productivity index and lower susceptibility of ‘Monte Parnaso’ navel orange (Citrus sinensis) trees to the bacteria Xanthomonas axonopodis pv. citri. The research was carried out in an experimental orchard, with ten-years-old trees, planted at spacement of 2.5m between trees and 6.0m between rows, located in Butia city, in the Central Depression of Rio Grande do Sul state. It was used an randomized blocks experimental design, with 7 treatments and 4 replications. The treatments consisted of the following rootstoks: Rangpur lime (C. limonia.), ‘Volkameriana’ lemon (C. volkameriana.), ‘Flying Dragon’ trifoliata orange (Poncirus trifoliata), ‘Caipira’ orange (C. sinensis), ‘troyer’ citrange (C. sinensis x P. trifoliata), ‘Sunki’ tangerine (C. sunki.) and ‘Swingle’ citrumelo (C. paradisi x P. trifoliata). The parameters evaluated were: number of fruits and leaves with citrus canker lesions per plant and at two previously selected and marked branches per plant, at different times . The results revealed that the ‘Swingle’ citrumelo and ‘Flying dragon’ rootstocks induced the highest productivity index and, the lowest incidence of citrus canker disease on leaves and fruits. ‘Rangpur’ lime and ‘Volkameriana’ lime rootstocks, promoted a heavy crop load, however, showed higher susceptibility to citrus canker disease.

Controle químico do cancro cítrico em plantas jovens sob manejo convencional e orgânico

The objective of the present work was to evaluate the development of the citrus rootstock Poncirus trifoliata, severity of citrus canker, caused by Xanthomonas citri pv. citri and the control of this disease with copper sprays, in conventional and organic management systems, at the Centro de Formacao da EMATER, located in Montenegro, Rio Grande do Sul. Plants were artificially inoculated with the bacteria. To control citrus canker, different sources of copper as well as concentrations and number of sprays were tested. In the organic system the bordeaux mixture was applied while in the conventional system copper oxichloride was sprayed. Plants trunk diameter, dry matter of the rootstocks and number of canker lesions on leaves and branches were evaluated in both systems. Citrus canker incidence on the rootstocks was equally intense, and the seedlings development was similar in both systems, but the budded plants grew better at the conventional system. Copper treatments were not effective in controlling citrus canker at the rootstocks due the high inoculum concentration. On the budded plants, with low inoculum concentration, both the Bordeaux mixture and the copper oxichloride controlled the disease, and the better treatments were when 0.3% metallic copper was applied with interval of 14 days. To improve citrus canker control by Bordeaux mixture on organic systems, there is a need of efficient control strategies of the citrus leaf miner.