Renato Vasconcelos Botelho

Phenology of "Niagara Rosada" grapevines grafted on different rootstocks grown on Cerrado (Brazilian savanna) of Goiás State, Brazil

The purpose of this experiment was to study the phenological stages from pruning to harvest of the ‘Niagara Rosada’ grapevine grafted on different rootstocks grown on Cerrado conditions (Brazilian savanna) at the Goias State, in the middle west of Brazil. The trial was carried out in Mineiros County, to evaluate phenological stages of ‘Niagara Rosada’ grapevines grafted on three rootstocks (‘Riparia do Traviu, ‘IAC-766 - Campinas’ and ‘IAC-572 - Jales’ and cultivated on climate and soil conditions of Cerrado (Brazilian savanna). The results showed that the cycle (from pruning to harvest) of ‘Niagara Rosada’ had differences on number of days according to the rootstock: 109 days on ‘Riparia do Traviu’, 112 days on ‘IAC-766’, and 113 on ‘IAC-572’, and the thermal summation requirements to complete the phenological cycle of ‘Niagara Rosada’ were 1,167.4, 1,197.9 and 1,207.4 degree-days, respectively. It can be concluded that climate and soil of Cerrado provided cycle reduction of ‘Niagara Rosada’. Key words : Vitis vinifera, rootstock, phenologycal characterization, Brazilian savanna.

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

The Northwest region of Sao Paulo State presents winter with mild temperatures, that allows grape crops between June and October, outside of harvest time from traditional grape-growing areas. In these conditions vine sprouting is irregular and low, requiring budbreak with chemical compounds. In this context, a trial was conducted in a commercial Centennial Seedless (Vitis vinifera L.) vineyard, where it was studied the effects of hydrogen cyanamide applied at different epochs. Vinegrapes were pruned at three different times (03-23, 04-05 and 04-20-2002) and the following doses of hydrogen cyanamide were used: 0, 0.75, 1.50, 2.25, 3.00 and 3.75%. The following variables were evaluated: percentage of sprouting, percentage of growing shoots, number of clusters, cluster weight and total yield. Independently of the hydrogen cyanamide dose, vines pruned earlier showed a lower percentage of sprouting. Hydrogen cyanamide applications presented a quadratic effect for percentage of sprouting, and number of clusters. Additionally, it was verified quadratic effects of hydrogen cyanamide applications for the variables percentage of growing shoots, cluster weight and total yield; in the prune carried out on April 20th . In the prune done on April 5th, it was observed linear increase for these variables. The estimated dose of hydrogen cyanamide for the highest sprouting was 2,89%.

Efeito do extrato de alho na quebra de dormência de gemas de videiras e no controle in vitro do agente causal da antracnose (Elsinoe ampelina Shear)

Considering the reduction or elimination of synthetic compounds used in sustainable fruit production systems, this work aimed to search for new alternatives for bud break dormancy and diseases control in grapevines. Single-bud cuttings of grapevines were sprayed with the following treatments: 1) control, 2) 1% SO (soybean oil), 3) 3% GE (garlic extract), 4) 3% GE + 1% SO. After that, the cuttings were kept in a growth chamber (25±2.5oC) for 56 days. The unique treatment that stimulated sprouting of grapevines cv. Isabel Precoce was 3% GE + 1% S), that reached 35% sprouting, differing statistically from the control (12.5%), 1% SO (17.5%) and 3% GE (15.0%). Probably, the stage of deep endodormancy of buds, after only 90 chilling hours (< 7.0oC), avoided better results of bud breaks treatments. Three experiments were carried out in vitro, with different garlic extract doses aiming to evaluate the control of the fungus Elsinoe ampelina. In all trials, there were quadratic effects on mycelial growth, without differences between garlic extract treatments, evidencing its fungicide effect, even for the lowest dose of 0.0615% GE.

Efeitos do ácido giberélico e do thidiazuron sobre as características dos frutos e do mosto da uva 'Niagara Rosada'

With the objective of evaluating the effects of the gibberellic acid and thidiazuron on clusters characteristics of the grapevine Niagara Rosada, two trials were carried out. In the first trial, it was used gibberellic acid (AG3) 0, 15, 30, 45, 60, 75 and 90 mg.l-1, applied in the bloom and repeated 14 days later (E1E2) and in the other treatment, the same compound and doses applied only once, 14 days after the bloom (E2); in the second experiment, thidiazuron (TDZ) 0, 5, 10, 15, 20, 25 and 30 mg.l-1, applied four days before antesis and repeated six days after the bloom (E1E2); and in the other treatment, the same compound and doses applied only once six days after the bloom (E2). From the obtained results, it has been verified that the treatments with thidiazuron, increased the setting of the berries, resulting in the increment of the clusters mass and the significant thickening of rachis. The fruits treated with thidiazuron presented desuniform maturation, berries with reduced mass and size, compact clusters, with low commercial value. Increases in the number of berries with increments in the mass of the clusters, had been also observed with applications of gibberellic acid. For the variable mass of the clusters, the best results obtained from estimate of the regression equation have been verified with applications 54mg.L-1 gibberellic acid, with values of 198,8g.

Extrato de alho e óleo vegetal no controle do míldio da videira

O objetivo deste trabalho foi verificar o efeito do extrato de alho e do oleo vegetal no controle do mildio da videira cv. Isabel (Vitis labrusca). A severidade da doenca, expressa pela area abaixo da curva de progresso da doenca (AACPD), e a germinacao de esporângios de seu agente causal Plasmopara viticola foram as variaveis avaliadas. Os tratamentos consistiram em 0; 5; 10; 15; 20; 25 ou 30 mL L-1 de extrato de alho adicionados de 2,5 mL L-1 oleo vegetal, calda bordalesa (1:1:100) e testemunha (sem tratamento). No teste de germinacao, utilizou-se mancozebe (2 g L-1) como tratamento-padrao. Em condicoes de campo, observou-se reducao da severidade do mildio com o oleo vegetal, sendo que o extrato de alho, a partir de 20 mL L-1, potencializou tal acao biocida. A germinacao dos esporângios de P. viticola variou em funcao do tempo de exposicao ao extrato de alho, nao apresentando boa eficiencia quando comparada ao tratamento com calda bordalesa e mancozebe. O oleo vegetal nao influenciou na germinacao dos esporângios desse patogeno.

Efeitos do thidiazuron e do ácido giberélico nas características dos cachos de uva de mesa cultivar Rubi, na região da Nova Alta Paulista

ABSTRACT – With the objective of evaluating the effects of thidiazuron and gibberellic acid on the cluster characteristics of ‘Rubi’grapes, a trial was conducted where was used thidiazuron at 5 and 10mg.L -1 and gibberellic acid at 20mg.L , associated or not . Theproducts were applied in three epochs: 14, 21 or 28 days after full bloom, by dipping the clusters. All treatments with growth regulatorsincreased the cluster weight. The berries and rachis weight were identically influenced, but it was less evident when the appl icationswere done 28 days after full bloom. Applications of thidiazuron at 5mg.L -1 , 14 or 21 days after full bloom, didn´t differ to the gibberellicacid applications for the variables in studying. There weren´t differences in the variables contents of soluble solutes, titrab le acidity,although the treatments with thidiazuron delayed cluster ripening until 7 days. Index terms: vine, Vitis vinifera , , cytokinin, gibberellin, growth regulator.O thidiazuron (TDZ: N-fenil-N-1,2,3-tidiazol-5-tiureia) euma citocinina sintetica que, no Brasil, e largamente utilizada nacultura do algodoeiro para provocar desfolhamento. Emfruticultura, ha trabalhos que comprovaram a eficiencia dothidiazuron na quebra de dormencia da macieira e pereira (Araujoet al., 1991; Francisconi et al., 1982), e no aumento do tamanho epegamento dos frutos de macas, kiwis e uvas (Petri et al., 1992;Reynolds et al., 1992).O acido giberelico (AG

Chitosan action on Plasmopara viticola and Elsinoe ampelina development in vitro and in grapevines cv. Isabel

This work aimed to evaluate the effect of chitosan on the control of fungi Elsinoe ampelina and Plasmopara viticola, the causal agents of downy mildew and anthracnose in grapevines, respectively. The concentrations of 0, 20, 40, 80 and 160 mg L-1 chitosan were used in the following trials: mycelial growth, spore germination, and experiment in field conditions. For the last two trials standard treatments with mancozeb and bordeax mixture were added. There was a reduction in E. ampelina mycelial growth and the highest chitosan concentration (160 mg L-1) decreased by 57% the fungus development at 192 hours after incubation. In the germination tests, the concentration of 160 mg L-1 chitosan reduced spore germination in E. ampelina by approximately 98% and P. viticola by 60%, not differing from the treatments with bordeaux mixture and mancozeb. In the field trial the highest chitosan concentrations (80 and 160 mg L-1) decreased anthracnose severity between 93 and 81%. For downy mildew, the concentration of 160 mg L-1 decreased the disease by approximately 81%. Based on these results, chitosan has a great potential for the control of downy mildew and anthracnose in grapevines.

Effects of late defoliations on chemical and sensory characteristics of cv. uva longanesi wines

In this study we investigated the effects of late leaf removal on the berry and wine composition and on wine sensory characteristics of Uva Longanesi, a late maturing red Italian grape variety, which wines are characterized by high levels of alcohol and excessive astringency, the latter apparently intensified by late defoliation practices. During 2008 season, spur-pruned trained vines were submitted to manual defoliation (4 basal leaves) at the onset (DEF I, 210 DOY) or at the end (DEF II, 231 DOY) of veraison and compared with non-defoliated plants (CON). On every DEF II vine, since defoliation until harvest, a cluster was shaded (DEF II + shading). A decrease of the berry soluble solids and skin anthocyanins was found in DEF I vines. Defoliation modified composition and sensory characteristics of wine with DEF II having higher alcohol strength and astringency compared to DEF I, whereas CON wines displayed intermediate values. The practice and timing of partial late defoliation greatly affected the chemical and sensory attributes of wine.

Desenvolvimento e fitossanidade de ameixeiras tratadas com silício em sistema orgânico

The objective of this study was to evaluate the effect of silicon (Si) applied via foliar in plum trees cv. Pluma 7 for the control of bacterial blight (Xanthomonas arboreal pv. pruni), oriental fruit moth (Grapholita molesta) and green aphid (Myzus persicae), as well as in plant development, in organic management. For this trial it was used the commercial product AgriSil ® (98% SiO2). The experiment was carried out in Guarapuava-PR, Brazil, by two consecutive cycles (2010/2011 and 2011/2012). The doses used were 0, 1, 2, 4 and 8 g L-1 of the commercial product, each two weeks. In both cycles, for the plum bacterial blight, it was verified until 85% incidence reduction, with quadratic effect of silicon doses. For the damage of oriental fruit moth, number of aphids, diameter and length of shoots no significant difference between the doses of SiO2 were found. For Si leaf content, a positive linear effect was verified in function of Si doses.

In vitro and foliar spray evaluation of Verbena officinalis (L.), Erythrina mulungu (Mart. ex Benth.), Quassia amara (L.), Bidens pilosa (L.) and Plantago lanceolata (L.), extracts on Meloidogyne incognita (Kofoid & White, 1919) Chitwood, 1949

El objetivo del estudio fue evaluar la eficacia de los extractos acuosos de cinco especies de plantas medicinales, Verbena officinalis (L.), Erythrina mulungu (Mart. ex Benth.), Quassia amara (L.), Bidens pilosa (L.) y Plantago lanceolata (L.) in vitro, y se pulverizaron en las plantas de tomates para el control de Meloidogyne incognita. Los experimentos in vitro fueron realizados en camaras de crecimiento en placas de ELISA de tipo acrilico. Los tratamientos fueron dosis de 0,10, 20, 30, 40 y 50 g • L-1 de diferentes extractos acuosos. En el dia dieciseis se evaluo el numero de juveniles segunda etapa (J2)nacidos por tratamiento. Los resultados mostraron que los extractos acuosos de V. officinalis, E. mulungu, Q. amara, B. pilosa y P. lanceolata reducen la eclosion de los juveniles de M. incognita, y el extracto acuoso de P. lanceolata mostro hasta 100% de reduccion de la tasa de eclosion. El ensayo in vivo se realizo en un invernadero, y para ello, habia cuatro pulverizaciones de diferentes extractos en los brotes de tomate. Segun los resultados de esta prueba, ninguno de los extractos por pulverizacion foliar era eficaz en el control de M. incognita. Sin embargo, no se debe descartar la eficiencia de estos extractos en el control de nematodos parasitos de plantas, pero mas estudios se llevan a cabo utilizando diferentes metodos de aplicacion, las dosis o metodos de extraccion de los principios activos de los extractos.