Biodegradable Polymer Packaging System for 'Benitaka' Table Grapes during Cold Storage.

A biodegradable polymer packaging system for 'Benitaka' table grapes (Vitis vinifera L.) was developed to inhibit the development of gray mold during refrigerated storage. The system consisted of packages and sachets containing Na2S2O5 to release sulfur dioxide (SO2), both produced with biodegradable films of starch, glycerol, and poly (adipate co-butylene terephthalate) (PBAT) produced via blown extrusion. The films were characterized in terms of thickness, density, mass loss in water, water vapor permeability, sorption isotherms, and mechanical properties. The table grapes were packed with biodegradable plastic bags containing SO2-releasing sachets inside. The experimental design was completely randomized, with four repetitions and five treatments: (a) control, without sachet containing Na2S2O5 and SiO2; (b) 2 g of Na2S2O5 + 2 g of SiO2; (c) 4 g of Na2S2O5 + 1 g of SiO2; (d) 4 g of Na2S2O5 + 2 g of SiO2; and (e) 4 g of Na2S2O5 + 4 g of SiO2. The bunches were stored in a refrigerated chamber at 1 ± 1 °C and relative humidity above 90%. The treatments were evaluated 30 and 45 days after the beginning of refrigerated storage and 3 days at room temperature. The grapes were evaluated based on the incidence of gray mold, mass loss, stem browning, shattered berries, and berry bleaching. The data were subjected to the analysis of variance, and the means were compared using Tukey's test at 5%. The biodegradable films had good processability during the production via blown extrusion, with good physical properties to be used in the packaging of grapes and the production of SO2-releasing sachets. The biodegradable polymer packaging system (biodegradable plastic bags + SO2-releasing sachets) inhibited the development of gray mold on 'Benitaka' table grapes for 45 days at 1 °C, preserving their quality, with low mass loss, few shattered berries, and rachis freshness.

Performance of Hop Cultivars Grown with Artificial Lighting under Subtropical Conditions.

The objective of this study was to determine the duration of the main phenological stages, plant growth development, yield, and cone quality of hop cultivars grown under artificial light (17 h per day) during vegetative development (early season) in a subtropical climate region. The study was conducted in Palotina, Paraná, Brazil (24° S), during the 2021 and 2022 growing seasons. The plants were cultivated in a 5.5 m high trellis system with artificial light supplementation during vegetative development. The hop cultivars Hallertau Mittelfrüher, Mapuche, Northern Brewer, Spalter, and Yakima Gold were used in the treatments. The duration of the phenological stages, vegetative growth (plant height, fresh mass of the plants, number of lateral branches per plant), components of productive yield (number of cones per side branch, number of cones per plant, fresh mass, length, and width of the cone, production of fresh cones per plant, and yield), and chemical components of the cones (alpha- and beta-acid contents, and essential oil concentrations) were recorded. The duration of the phenological stages was visually evaluated, and plant growth was analyzed using non-linear log-logistic regression. The remaining data were subjected to analysis of variance and the means were compared using Tukey's test. The data were also subjected to multivariate analysis using the principal components test, correlation analysis, and hierarchical grouping. The cultivar Mapuche was considered an early hop in both seasons, and the cultivars Spalter and Yakima Gold were considered early cultivars in the second season. In both seasons, the productive yield components were positively correlated with the precocity of the cultivars, in which Mapuche in the 2021 season and Mapuche, Spalter, and Yakima Gold in the 2022 season had the highest mean of the number of cones per side branch and per plant, production per plant, and productivity. The cultivar Yakima Gold had a positive correlation with the chemical quality of cones, alpha and beta acid contents, and essential oil concentrations, for both seasons.

Chitosan/silica nanocomposite-based formulation alleviated gray mold through stimulation of the antioxidant system in table grapes.

The main purpose of this study was to explore the ability of a novel silica/polysaccharide polymer-based formulation, namely, chitosan/silica nanocomposites (CSNs), to directly affect Botrytis cinerea in vitro and in inoculated berries, and indirectly to induce natural host resistance via enzymatic and nonenzymatic antioxidants against gray mold of table grapes. The results indicated a positive correlation in in vitro tests in terms of radial growth, spore germination and germ tube elongation, where those parameters were completely inhibited by CSN at 1%. SEM and TEM investigations showed that morphological and internal structural damage was observed in B. cinerea-hyphae/spores treated with CSN. Additionally, most of the treated spores were affected, and cellular vacuolization and cytoplasmic disorganization were observed. The results revealed that CSN reduced gray mold incidence and severity on inoculated berries directly and indirectly. In direct activity, CSN (1%) reduced mold incidence and severity by 100% compared to the control. In indirect activity, mold incidence and severity was reduced by 51% and 64%, respectively. CSN significantly increased superoxide dismutase, ascorbate peroxidase, peroxidase, total phenol and flavonoid at 48 h post-treatment by 1.2-, 1.6-, 1.3-, 1.3- and 1.6-fold, respectively, in grape-treated tissues. It could be concluded that CSN, as a promising alternative control method against gray mold of table grapes, can directly affect the pathogen and indirectly enhance the natural host resistance of the antioxidant system.

Salt Solution Treatments Trigger Antioxidant Defense Response against Gray Mold Disease in Table Grapes.

To obtain a clear understanding of the mode of action of potassium bicarbonate (PB), sodium silicate (SSi) and calcium chelate (CCh) solutions (1%) in inducing resistance to gray mold disease in table grapes, enzymatic and nonenzymatic investigations were carried out. In particular, changes in the activity of the enzymes superoxide dismutase (SOD), ascorbate peroxidase (APX) and peroxidase (POD), total phenolic content and total flavonoid content were studied. As indirect action, PB, SSi and CCh reduced the incidence of gray mold by 43%, 50% and 41%, respectively. The highest activity of SOD was detected at 48 h in SSi-treated tissue, PB-treated tissue and CCh-treated tissue, and it was 1.7-, 1.4- and 1.2-fold higher, respectively, compared to the control. The APX activity was significantly higher in SSi-treated tissue than in the control at 24, 48 and 72 h and showed an increase in activity 2-fold for all times. Additionally, PB, SSi and CCh increased the activity of POD by 1.4-, 1.2- and 2.7-fold at 48 h posttreatment, respectively. The results showed that CCh was the most pronounced salt to increase both total phenol and flavonoid contents by 1.3 and 2.1, respectively. Additionally, the three tested salts induced an increase in total phenols and total flavonoids at 48 h posttreatment. The obtained result is one more movement towards an overall understanding of the mechanism by which salt solutions act as antimicrobial agents against gray mold of table grapes.

Analysis of the phenolic composition and yield of 'BRS Vitoria' seedless table grape under different bunch densities using HPLC-DAD-ESI-MS/MS.

Grapes are considered to be a major source of phenolic compounds as compared with other fruits. To improve the quality of table grapes, some techniques like thinning can be used. In addition, grape cultivars with distinct characteristics are directly linked to its phenolic profile. This study aimed to identify and quantify the phenolic compound profile and yield of the hybrid 'BRS Vitoria' seedless table grape under different bunch densities, using a combination of solid-phase extraction (SPE) methodologies and analytical high-performance liquid chromatography-diode array detector with tandem mass spectrometry (HPLC-DAD-ESI-MS/MS). A trial was carried out in 2016, in a commercial vineyard at Marialva, state of Parana (South Brazil). Three weeks after anthesis, the following bunch densities were evaluated: 4.0, 4.5, 5.0, 5.5, and 6 bunches per m2 (corresponding to an estimation of 16, 18, 20, 22, and 24 tons ha-1). The randomized block design was used as a statistical model with each treatment was replicated four times, with one vine per plot. Different characteristics were evaluated at harvest, e.g., soluble solids content (SS), total acidity (TA), maturation index (MI = SS/TA), bunch and berry masses, yield, as well hydroxycinnamic acid derivative (HCAD), anthocyanin, flavonol, and flavan-3-ol contents by HPLC-DAD-ESI-MS/MS analysis. The evaluated bunch densities did not interfere with the physicochemical characteristics of the berries, such as SS and MI. Under the density of 6.0 bunches per m2, the highest yield of 25 tons ha-1 was reached. Under all bunch densities, the phenolic profile presented the same compounds, but at different concentrations. Under a density of 5.0 bunches per m2, the compounds belonging to the anthocyanin and flavonol families were present in high concentrations. In contrast, at the densities of 4.0 and 4.5 bunches per m2, there was a reduction in the flavan-3-ol content. With respect to stilbenes, only the trans-piceid and its cis- isomer were detected. However, their concentrations had no significant influence on the evaluated bunch densities.

Control of Gray Mold on Clamshell-Packaged 'Benitaka' Table Grapes Using Sulphur Dioxide Pads and Perforated Liners.

The use of vented clamshells has become popular in the packaging of grapes for local and international markets. The aim of this study is to evaluate the postharvest preservation of 'Benitaka' table grapes individually packaged in vented clamshells using different types of SO2-generating pads and perforated plastic liners during cold storage. A completely randomized design with four replications in a two-factor arrangement with an additional treatment [(4 × 3) + 1] was used. The trials were carried out under two situations: Artificial or natural infections with Botrytis cinerea, which is the causal agent of gray mold on table grapes. The incidence of gray mold, shattered berries, and stem browning were evaluated at 30 and 45 days of cold storage at 1 ± 1 °C and 3 days of shelf-life at 22 ± 1 °C after the period of cold storage. Mass loss and berry firmness were also examined at the end of the cold storage period. The use of dual-release SO2-generating pads containing 5 or 8 g of a.i. and slow-release pads with 7 g of a.i. was effective in controlling the incidence of gray mold in grapes packaged in vented clamshells and kept under cold storage for up to 45 days. Under these storage conditions, perforated plastic liners with 0.3% ventilation area or micro-perforated liners with 1.0% ventilation area reduced the percentage of mass loss and shattered berries.

Ultra-Structural Alterations in Botrytis cinerea-The Causal Agent of Gray Mold-Treated with Salt Solutions.

Potassium bicarbonate (PB), calcium chelate (CCh), and sodium silicate (SSi) have been extensively used as antifungal generally recognized as safe (GRAS) compounds against plant pathogenic fungi. In this research, in in vitro tests, the radial growth, conidial germination, and germ tube elongation of Botrytis cinerea was completely inhibited at 0.3% of PB, SSi, and CCh. In in vivo tests, application of PB, SSi, and CCh completely inhibited the occurrence of gray mold incidence of inoculated 'Italia' grape berries at concentrations of 1.0, 0.8, and 0.8%, respectively. In order to investigate the detailed mechanisms by which salts exhibited antifungal activity, we analyzed their influence on morphological changes by scanning electron microscopy (SEM) and transmission electron microscopy (TEM) and also on reactive species of oxygen (ROS), mitochondrial membrane potential (MMP), and adenosine triphosphate (ATP) content. Defects such as malformation and excessive septation were detected on salt-treated hyphae morphology observed by SEM. The internal structure of conidia treated or not with salt solutions was examined by TEM. In treated conidia, most of the conidia were affected and cellular vacuolization and cytoplasmic disorganization was observed. For ROS accumulation, a higher increase was observed in fluorescent conidia in presence of PB, SSi, and CCh by 75, 68, and 70% as compared to control, respectively. MMP was significantly decreased after salt application indicating a loss of mitochondria function. Also, luminescence showed that B. cinerea-conidia treated with salts contained less ATP than the untreated conidia. The results obtained herein are a step towards a comprehensive understanding of the mode of action by which salts act as antifungal agents against B. cinerea.

Synergistic effect of a novel chitosan/silica nanocomposites-based formulation against gray mold of table grapes and its possible mode of action.

Ecofriendly nanostructured materials have been proposed as promising alternative control means to prevent plant diseases. Chitosan nanoparticles (CN), silica nanoparticles (SN) and chitosan-silica nanocomposites (CSN) were synthesized and their morphology and structure was characterized by transmission electron microscope (TEM), scanning electron microscopy (SEM), infrared spectra (FT-IR) and Raman spectroscopy. Their antifungal efficiency against Botrytis cinerea, the causal fungus of gray mold disease of table grapes, was tested in vitro and in vivo (under artificial and natural infections). In vitro tests showed that CN, SN and CSN reduced fungal growth by 72, 76 and 100%, respectively at 1% as compared to control. Under natural infection, at the end of cold storage, CSN was the most effective treatment, and reduced the development of gray mold by 59 and 83%, for 'Italia' and 'Benitaka' grapes, respectively as compared to the water control. Results indicate that a synergistic effect of CSN against gray mold was observed. The impact of tested nanocomposites on soluble solids - TSS, titratable acidity - TA, TSS/TA, berry color, mass loss, stem browning and shattered berries was investigated. No negative effect of tested nanomaterials in term of grape quality was observed. For 'Italia' table grape, CN and CSN can preserve bunches from mass loss as compared to control. Also, the effect of CSN on reactive species of oxygen (ROS), ATP content and mitochondrial membrane potential (MMP) of B. cinerea spores was determined to verify its mode of action. The obtained results suggested CSN, as alternative control means, to reduce/substitute the use of fungicides to control gray mold of table grapes while maintaining grape quality.

Berry-cluster thinning to reduce compactness of ‘Black Star’ table grapes / Despenca como método de raleio para reduzir a compacidade de cachos da uva de mesa ‘Black Star’

ABSTRACT: The berry-cluster thinning technique was evaluated at different phenological times to prevent bunch compactness of ‘Black Star’ table grape, a new somatic mutation of ‘Brasil’ grape. The trial was carried out during 2012 and 2013 seaons in a vineyard situated in Marialva, PR, Brazil. Vines were trained in an overhead trellis system and spaced at 3x4m. The randomized block design was used as a statistical model with five replications and five treatments. The following treatments were evaluated: control; brushing prior to anthesis; and berry-cluster thinning at different times, when berries were 3-6, 7-10, or 11-15mm in diameter. The prevalence of bunch compactness was evaluated considering the levels: loose, medium loose, and dense bunches. The main physico-chemical characteristics of grapes and yield were also appraised. The data obtained were submitted to ANOVA, and toTukey’s test at 5% was applied. So, thinning is a mandatory practice to avoid bunch compactness of ‘Black Star’ grapes. The technique has to be performed, preferably, by means of brushing prior to anthesis, and the failure to accomplish this practice at this time, berry-cluster thinning when berries are 11-15mm in diameter can be used.

RESUMO: O método de raleio de bagas em diferentes fases fenológicas reduz a compactação de cachos da uva fina de mesa ‘Black Star’, uma nova mutação da uva ‘Brasil’. As videiras foram conduzidas em latada em espaçamento 3x4m, e o experimento foi realizado nas safras 2012 e 2013. O delineamento experimental consistiu em blocos casualizados, com cinco repetições e cinco tratamentos: controle sem raleio; raleio com escova plástica realizado no pré-florescimento e; despenca quando as bagas apresentavam 3-6, 7-10 ou 11-15mm de diâmetro. A compacidade predominante dos cachos foi avaliada de acordo com a seguinte classificação: cachos soltos, medianamente soltos e compactos. As características físico-químicas dos cachos e a produtividade também foram avaliadas. Os dados foram submetidos à análise de variância e as médias comparadas pelo teste de Tukey a 5%. Verificou-se que o raleio de bagas é uma prática obrigatória na uva ‘Black Star’ para diminuir a compacidade dos cachos. A operação deve ser realizada, preferencialmente, com a escova plástica no pré-florescimento, e na impossibilidade de executar ou finalizar essa prática nesta fase, pode-se empregar a despenca quando as bagas apresentarem 11-15mm de diâmetro.

Indole butyric acid and substrates influence on multiplication of blackberry 'Xavante' / Influência do ácido indol butírico e substratos na propagação de amoreira-preta 'Xavante'

Blackberry is a shrubby plant specie which has a high economic importance among agriculture crops. Brazil is the major country of Latin America with the highest future scope for blackberries. For availability of good quality and maximum quantity of seedlings, the present study was carried out at the Universidade Estadual de Londrina,PR from January to March in 2013. The aim of the study was to evaluate the multiplication of blackberry 'Xavante' cuttings under different type of substrates treated with different levels of indole butyric acid (IBA). The experiment was laid out in randomized complete block design with 2 factors, i.e., substrate (rice husk, vermiculite and coconut fiber) and IBA (0; 1,000; 2,000 and 3,000mg L-1), with 5 replications. Each replicate consisted of 10 cuttings. The variables studied were: cutting rooting, cutting survival, leaf retention, cuttings with new leaves, number of major roots, length of major roots and roots dry weight. Most of the variables were significantly affected by both substrate and IBA. Rice husk and vermiculite performed better than coconut fiber and provided the same results for most of the variables, while coconut fiber showed lower performance for all of the variables studied. IBA significantly affected the rooting and the number of major roots. It is concluded that for multiplication of blackberry 'Xavante', both rice husk and vermiculite can be used along 2,000mg L-1 of IBA.

A amoreira-preta é uma espécie vegetal arbustiva que apresenta relevante importância econômica entre as culturas frutíferas. O Brasil é o maior produtor da América Latina. Para disponibilidade de boa qualidade e alta quantidade de mudas, o presente estudo foi realizado na Universidade Estadual de Londrina, PR, de janeiro a março, em 2013.O objetivo foi avaliar a mulitiplicação de amoreira-preta 'Xavante' em vários tipos de substratos sob diferentes níveis de ácido indol butírico (AIB). O delineamento experimental foi em blocos casualizados com dois fatores: substrato (casca de arroz carbonizada, vermiculita e fibra de coco) e AIB (0, 1.000, 2.000 e 3.000mg L-1), com cinco repetições, sendo cada repetição constituída por 10 estacas. As variáveis ​​avaliadas foram: estacas enraizadas, sobrevivência das estacas, retenção de folhas, estacas com folhas novas, número de raízes, comprimento de raízes e massa seca dos raízes. A maioria das variáveis foi significativamente afetada pelos substratos e AIB. A casca de arroz e vermiculita apresentaram melhor desempenho quanto à maioria das variáveis, enquanto a fibra de coco apresentou dempenho inferior. O AIB afetou significativamente a porcentagem de enraizamento e o número de principais raízes. Conclui-se que, para a otimizar a multiplicação de mudas de amoreira-preta 'Xavante' , tanto a casca de arroz carbonizada como a vermiculita podem ser usadas, associadas a 2.000mg L-1 de AIB.

Substratos no enraizamento de estacas herbáceas de amora-preta Xavante / Substrates on rooting of blackberry Xavante herbaceous cuttings

A amora-preta (Rubus spp.) destaca-se entre as espécies que apresentam boas perspectivas de cultivo em áreas de agricultura familiar. Visando a otimizar a multiplicação de mudas dessa espécie, o objetivo deste trabalho foi avaliar o uso de substratos e concentrações do ácido indolbutírico (AIB) no enraizamento de estacas de amora-preta Xavante. O delineamento experimental foi o inteiramente casualizado em arranjo fatorial 3x2 (três tipos de substratos e duas concentrações de AIB), com cinco repetições de sete estacas, sendo adotados os fatores: tipos de substratos (casca de arroz carbonizada, vermiculita grânulos médios e fibra de coco) e tratadas ou não com AIB (0 e 1000mg L-1). Após 80 dias, foram avaliadas as variáveis: sobrevivência das estacas; retenção foliar; estacas enraizadas; número de raízes por estaca; comprimento da maior raiz; massa seca das raízes por estaca; e pH; condutividade elétrica; densidade e capacidade de retenção de água dos substratos. Não houve influência dos substratos e da aplicação de AIB sobre a porcentagem de estacas enraizadas, verificando-se alta eficiência no enraizamento das estacas de amora-preta Xavante (86,2%). Para a porcentagem de sobrevivência das estacas, o melhor resultado foi obtido sem a aplicação de AIB. Conclui-se que a amora-preta Xavante pode ser propagada por estaquia herbácea com eficiência, sem o uso de AIB, utilizando-se preferencialmente o substrato casca de arroz carbonizada como opção de baixo custo.

The blackberry (Rubus spp.) stands out among the species that have good prospects for cultivation in areas of family farm agriculture. In order to optimize the multiplication of seedlings of this species, the aim of this research was to evaluate the use of different substrates and concentrations of indolebutyric acid (IBA) on the rooting of cuttings of blackberry Xavante. The experiment was performed using the completely randomized design in a 3x2 factorial arrangement (three substrates and two concentrations of IBA), with five replications of seven cuttings, and the following factors were adopted: types of substrates (vermiculite medium granules, carbonized rice husk and coconut fiber) and treated or not treated with IBA (0 and 1000mg L-1). After 80 days, the following variables were evaluated: cuttings survival; leaf retention; rooted cuttings; root number per cutting; length of the longest root; dry weight of roots per cutting; and pH; electrical conductivity; bulk density and water retention capacity of the substrates. There was no influence of the substrates and the IBA on the percentage of rooted cuttings, verifying the high efficiency on rooting of the blackberry Xavante cuttings (86.2%). For the percentage of cuttings survival the best result was obtained without the IBA application. It was concluded that the blackberry Xavante can be propagated by herbaceous cuttings efficiently, using the carbonized rice husk as low-cost option.

Fenologia e produção das videiras 'Alicante' e 'Syrah' em safra fora de época / Phenology and production of 'Alicante' and 'Syrah' grapevines grown out of season

O objetivo do trabalho foi caracterizar a fenologia e a produção das videiras 'Alicante' e 'Syrah' (Vitis vinifera L.) cultivadas fora de época. A área experimental foi instalada em uma propriedade da Vinícola Intervin®, localizada em Maringá, PR. Os vinhedos foram estabelecidos em julho de 2001 e as plantas conduzidas no sistema latada (4,0x1,5m), enxertadas sobre o porta-enxerto IAC 766 'Campinas'. As podas longas de produção (oito gemas) foram realizadas no fim de fevereiro de 2008 e 2009. As avaliações tiveram início a partir da poda de frutificação durante duas safras consecutivas fora de época. Foram utilizadas 20 plantas representativas de cada variedade, sendo a colheita de ambas as safras realizadas em meados de julho. Avaliou-se a duração em dias das principais fases fenológicas, as características físico-químicas das bagas e as características produtivas de cada variedade. Verificou-se que a 'Alicante' apresenta ciclo médio de 138,0 dias, mosto com 15,4°Brix, 1,9 por cento de ácido tartárico e produtividade de 14,5t ha-1, enquanto a 'Syrah' apresenta ciclo médio de 132,5 dias, 14,5°Brix, 2,9 por cento de ácido tartárico e produtividade de 11,4t ha-1.

This study aimed to characterize the phenology and the production of 'Alicante' and 'Syrah' grapes (Vitis vinifera L.) produced out of season. The experimental area was located in a property belonging to the Intervin® Winery, at Maringá, PR. The vineyards were established in July, 2001 and the vines were trained in an overhead trellising system (4.0x1.5m), grafted on IAC 766 'Campinas' rootstock. The long pruning of production (eight buds) was held in late February of 2008 and 2009. The evaluations started from the pruning of production, in two years, using 20 representative vines of each variety, and the harvesting of both crops were performed on early July. The phenology of the trees was evaluated as the duration in days of the most important phases, as well it was analyzed the berries physico-chemical characteristics. The production characteristics of each variety were also estimated. It was verified that 'Alicante' showed a mean cycle of 138.0 days, must with 15.4°Brix, 1.9 percent of tartaric acid and productivity of 14.5t ha-1, while 'Syrah' showed a mean cycle of 132.5 days, 14.5°Brix, 2.9 percent of tartaric acid and productivity of 11.4t ha-1.

Produção fora de época da videira 'BRS Clara' sob cultivo protegido / Out of season production of 'BRS Clara' seedless grape under protected cultivation

No norte do Paraná, a viticultura diferencia-se de outras regiões produtoras, pois são obtidas, nessa região, duas safras em um ano, uma regular e outra fora de época. Entretanto, o clima quente e úmido da região favorece a ocorrência do míldio (Plasmopara viticola) e uma alternativa para minimizar esse problema é o emprego do sistema de produção de uvas sob cultivo protegido. O trabalho teve como objetivo avaliar a produção fora de época da videira 'BRS Clara' sobre os porta-enxertos 'IAC 572 Jales' e 'IAC 766 Campinas', submetida à diferentes tipos de cultivo protegido. O delineamento experimental empregado foi o de blocos ao acaso com quatro repetições, em arranjo fatorial 7x2 (sete tipos de cultivo protegido e dois porta-enxertos). Os tratamentos foram: a. sombrite sem fungicidas para míldio; b. sombrite com fungicidas para míldio (padrão de controle da região); c. cobertura plástica sem fungicidas para míldio; d. cobertura plástica e 50 por cento de redução do padrão de fungicidas para míldio; e. cobertura plástica e 75 por cento de redução do padrão de fungicidas para míldio; f. cobertura plástica com fosfito e cobre; e g. cobertura plástica sem fungicidas. Os porta-enxertos 'IAC 766' e 'IAC 572' são indicados para a produção da uva sem semente 'BRS Clara' na região norte do Paraná; o emprego da cobertura plástica permite a redução de até 75 por cento do número de aplicações de fungicidas no cultivo da uva 'BRS Clara', mas essa cobertura, por si só, não é suficiente para prevenir a ocorrência de míldio nos cachos, em condições de umidade elevada.

The viticulture of the north of Parana state differs from other regions, because in this area two crops are obtained a year, a regular and an out of season ones. However, the hot and humid climate of the region favors the occurrence of downy mildew (Plasmopara viticola), an alternative to minimize this problem is the use of grape production under protected cultivation. The study aimed to evaluate the out of season production of grapevine 'BRS Clara' on 'IAC 572 Jales' and 'IAC 766 Campinas' rootstocks, submitted to different types of protected cultivation. The randomized block design was used as a statistical model with four replications arranged in a factorial 7x2 (seven kinds of protected cultivation and two rootstocks). The treatments were: a. plastic screen without fungicides for downy mildew; b. plastic screen with fungicides for downy mildew (standard control of the region); c. plastic cover without fungicides for downy mildew; d. plastic cover and 50 percent of reduction of the standard fungicides for downy mildew; e. plastic cover and 75 percent of reduction for the standard fungicide mildew; f. plastic cover with phosphite and copper and; g. plastic cover without fungicides. The rootstocks 'IAC 766' and 'IAC 572' are suitable for the production of 'BRS Clara' in north of Parana state; the use of plastic cover allows a reduction up to 75 percent of the number of applications of fungicides in 'BRS Clara'; the plastic cover itself is not sufficient to prevent the occurrence of downy mildew in bunches under conditions of high humidity.

Enraizamento de estacas de azaleia (Rhododendron simsii Planch.) no outono em AIB e diferentes substratos / Rooting of azalea cuttings (Rhododendron simsii Planch.) in the fall of AIB and different substrates

A azaleia é uma planta ornamental propagada comercialmente por meio de estacas, sendo difícil o seu o enraizamento em muitos casos, o que resulta em baixa produção de mudas. O objetivo do trabalho foi avaliar o uso do AIB e o efeito de diferentes substratos sobre o enraizamento de estacas herbáceas de azaleia no outono. O delineamento experimental foi o inteiramente casualizado, com cinco repetições, em um fatorial 2x3, sendo adotados os fatores: aplicação ou não de ácido indol butírico - AIB (0mg L-1 e 1.000mg L-1) e tipos de substratos (vermiculita - grânulos médios, casca de arroz carbonizada e fibra de coco). Após 76 dias, foram avaliadas as seguintes variáveis: retenção foliar ( por cento), estacas enraizadas ( por cento), sobrevivência das estacas ( por cento), comprimento da maior raiz, número de folhas, massa de matéria fresca das raízes por estaca, pH e condutividade elétrica dos substratos. Os resultados mostraram não haver diferenças para o enraizamento pela aplicação ou não de AIB. As estacas enraizadas em casca de arroz carbonizada e vermiculita apresentaram número superior de folhas em relação às estacas do substrato fibra de coco. No entanto, a fibra de coco e a casca de arroz carbonizada proporcionaram um maior comprimento de raiz. Para massa de matéria fresca por estaca, a fibra de coco também apresentou o melhor resultado. Não houve contribuição do AIB no enraizamento de estacas de azaleia, e o substrato fibra de coco foi o que apresentou melhor desempenho para o enraizamento das estacas.

Azalea is an ornamental plant commercially propagated by cuttings, and their rooting process in many cases, is difficult, which results in decreased production of seedlings. The objective of this study was to evaluate the use of IBA and the effect of different substrates on the rooting of cuttings of azalea in the fall. A randomized design with five replications in a factorial array was used as a statistical model, and it was adopted the following factors: types of substrates (vermiculite - medium granules, hull rice coal and coconut fiber), and indole butyric acid - IBA (0mg L-1 and 1,000mg L-1). After 76 days, the following variables were evaluated: leaf retention ( percent), rooted cuttings ( percent), cuttings survival ( percent), length of the longest root, number of leaves, fresh weight of roots per cutting, pH and electrical conductivity of the substrates. There was no difference of using IBA to improve rooting. The hull rice coal and vermiculite substrates resulted in a higher number of leaves on cuttings than coconut fiber. However, the coconut fiber and hull rice coal provided a greater root length. For fresh weight of roots per cutting, the coconut fiber also provided the best results. It was concluded that there was no contribution of IBA on the rooting of azalea, and coconut fiber substrate was more suitable for its rooting.

Enraizamento de estacas de Psidium guajava L. Século XXI tratadas com ácido indolbutírico veiculado em talco e álcool / Cutting rooting of Psidium guajava L. Século XXI guava treated with indolebutyric acid with talc and alcohol as a vehicle

Na produção comercial de Psidium guajava L. (goiabeira), a qualidade das mudas é de fundamental importância, a fim de garantir a homogeneidade, a rápida formação, a alta produtividade e o início precoce da produção, tornando-se imprescindível a utilização da propagação assexuada. O objetivo deste trabalho foi avaliar o enraizamento de estacas de Psidium guajava L. 'Século XXI' tratadas com diferentes concentrações de ácido indolbutírico (AIB) veiculados em talco e álcool. Foram utilizadas estacas herbáceas de 10 - 12cm, submetidas a duas formas de aplicação (solução hidroalcóolica e talco) e três concentrações (0; 1000 e 2000mg L-1) de AIB. As estacas foram enraizadas em caixas plásticas contendo casca de arroz carbonizada. O delineamento experimental foi o inteiramente casualizado, com cinco repetições, em um fatorial 2x3, sendo cinco repetições de 10 estacas. Após 95 dias, foram avaliadas as variáveis: sobrevivência das estacas ( por cento); retenção foliar ( por cento); estacas enraizadas ( por cento); número de raízes por estaca; comprimento de raízes por estaca (cm) e massa seca das raízes por estaca (g). Os melhores resultados para a porcentagem de estacas enraizadas (28,5 por cento); número de raízes por estaca (12,10) e comprimento da raiz (6,79cm) foram obtidos com a maior concentração de AIB. A partir dos resultados obtidos, conclui-se que a aplicação de 2000mg L-1 de AIB proporcionou as melhores características de enraizamento em estacas herbáceas da goiabeira 'Século XXI' e a sua veiculação em talco se mostrou mais eficiente que em álcool.

In commercial production of Psidium guajava L. (guava) seedlings quality is of paramount importance in order to ensure uniformity, rapid formation, high productivity and early production, making it essential to vegetative propagation. The aim of this research was to evaluate the cutting rooting of Psidium guajava L. 'Século XXI' treated with different concentrations of indolebutyric acid (IBA) with talc and alcohol as a vehicle. Herbaceous cuttings with 10-12cm were submitted to two forms of applications (alcoholic talc and alcoholic solution) and three doses (0; 1000 and 2000mg L-1) of IBA. The cuttings were placed in plastic boxes containing carbonized rice husk. The experimental design was complete randomized, two-way ANOVA (2x3) with five replicates of ten cuttings. After 95 days, the following variables were evaluated: cutting survival rate ( percent); foliar retention ( percent); rooted cuttings ( percent); root number per cutting; root length per cutting and dry root matter per cutting (g). The best results for the percentage of rooting (28.5 percent), number of roots per cutting (12.10) and root length (6.79cm) were obtained with the highest concentration of IBA. The results showed that the application of 2000mg L-1 of AIB is the most appropriate to provide the best rooting characteristics of 'Século XXI' guava and the use of talc as an vehicle is more efficient than alcohol.

Enraizamento de estacas semilenhosas de pessegueiro "Okinawa" sob efeito de lesão e ácido indolbutírico / Semi-hardwood cuttings rooting of peach tree 'Okinawa' under effect of lesion and indolebutyric acid

Buscando técnicas mais eficientes na propagação de mudas de pessegueiro, desenvolveu-se este trabalho com o objetivo de verificar o efeito da lesão e de diferentes concentrações de ácido indolbutírico (AIB) no enraizamento de estacas semilenhosas do pessegueiro "Okinawa". Foram utilizados dois tipos de estacas (com e sem lesão na base), tratadas por imersão da base por cinco segundos em cinco concentrações de AIB (0, 500, 1.000, 1.500 e 2.000mg L-1). Após o tratamento, as estacas foram colocadas para enraizamento em caixas plásticas, contendo casca de arroz carbonizada, em câmara de nebulização. Após 60 dias do início do experimento, verificou-se que a lesão na base proporcionou aumento da porcentagem de estacas enraizadas e do número de raízes por estaca. Na propagação por estaquia semilenhosa de pessegueiro "Okinawa", os melhores resultados foram observados para estacas que sofreram lesão e que foram tratadas com AIB em concentrações de 1.500 e 2.000mg L-1.

In search of more efficacious techniques in peach plant propagation, this research was aimed at verifing the effect of the lesion and different concentrations of indolbutiric acid (IBA) on rooting of semi-hardwood cuttings rooting of the 'Okinawa' peach. A randomized design was used arranged on a 2 x 5 factor with 4 repetitions and 8 cuttings for plot. Two types of cuttings were used (with and without lesion in the base) and five concentrations of IBA (0; 500; 1000; 1500 and 2000mg L-1). After 60 days from the beginning of the experiment, it was verified that the base injury leads to an increase in the percentage of root cuttings and in the number of roots per cuttings. In the semi-hardwood propagation of 'Okinawa' peach, the best results were observed for cuttings with lesion that were treated with IBA in concentrations ranging from 1500 to 2000mg L-1.