ABSTRACT In Brazilian regions affected by the citrus sudden death disease, sweet orange cultivation depends on the use of resistant rootstocks. Rangpur lime was mainly replaced by Swingle citrumelo and Sunki mandarin rootstocks, more drought-sensitive ones. The diversification of scion selections is also desirable aiming at the increasing demand for not from concentrate orange juice (NFC) that requires high-quality fruits. In this work, we evaluated the performance of 6 selections of Valencia (IAC, Dom João, Late Burjasot IVIA 35-2, Rhode Red SRA 360, Temprana IVIA 25 and Campbell) and Natal IAC sweet oranges grafted onto Swingle citrumelo and Sunki mandarin. The planting occurred in 2001 under rain-fed cultivation in Bebedouro, northern São Paulo state, Brazil. The outline was made through randomized blocks in a 7 × 2 factorial design (selections × rootstock), with 4 replications and 2 trees in unit. Both rootstocks performed well in the region. Sunki mandarin rootstock induced greater tree size and production per plant to the scion selections, 38 and 21%, respectively, plus higher precocity of production compared to Swingle citrumelo. The later determined a greater productive efficiency, as well as a greater percentage of juice in general, albeit with lower concentrations of soluble solids and acidity. Natal IAC, Valencia IAC and Rhode Red Valencia selections presented a higher accumulated production, on average, 218.6 kg∙plant−1 (2004 – 2008), and a higher productive efficiency (kg fruit∙m−3 of canopy) due to their smaller tree size. All assessed selections produced fruits with high soluble solids content that were suitable for juice processing.

Este trabalho teve como objetivo determinar o efeito de recobrimentos proteicos e de quitosana na conservação de goiabas 'Kumagai'. Utilizaram-se recobrimentos de quitosana com e sem glicerol (1:1) nas concentrações de 2%, 4% e 6%, concentrado proteico de soro de leite (CPSL) com glicerol (1:1) nas concentrações de 6% e 8% e glúten com glicerol (1:1) a 10% e 12%. Os recobrimentos foram aplicados por imersão das goiabas nas soluções por 10 segundos e posterior à secagem em temperatura ambiente com ventilação forçada. Em seguida as frutas foram armazenadas em condição ambiente (22±2 ºC e 70±5% UR) durante oito dias. O tratamento com quitosana 6% sem glicerol impediu o amadurecimento das frutas, odor alcoólico no oitavo dia. Com exceção do tratamento com quitosana a 6%, nos tratamentos os efeitos foram semelhantes e não alteraram o tempo de conservação das goiabas.

The objective of this study was to evaluate the effects of chitosan and protein coatings on the conservation of 'Kumagai' guavas. Chitosan coatings with and without glycerol (1:1) at 2; 4 and 6% concentrations, whey protein concentrate (WPC) coatings with glycerol (1:1) at 6 and 8% concentrations and gluten with glycerol coatings (1:1) at 10 and 12% concentrations were used. Coatings were applied by dipping guavas in the solutions for 10 seconds and dried at room temperature in a forced air circulation chamber. Subsequently, fruit were stored at room temperature (22±2 ºC and 70±5%RH) for 8 days. Chitosan coating at 6% without glycerol prevented fruit ripening and fruit gave off an alcoholic smell on the 8th day. Apart from the chitosan coating at 6%, the other treatments caused similar responses when compared to control group within the fruit conservation period considered.

A alta perecibilidade da goiaba é o principal problema enfrentado pelos produtores na comercialização da fruta in natura, tanto no mercado nacional, como no internacional. O 1-metilciclopropeno (1-MCP) é um regulador vegetal conhecido como bloqueador da ação do etileno, empregado para retardar o amadurecimento de frutos e estender sua vida útil. Assim, o presente trabalho teve por objetivo determinar os efeitos da aplicação do regulador vegetal 1-MCP sobre a qualidade pós-colheita de goiabas 'Kumagai'. As goiabas foram colhidas quando a cor da casca começou a mudar de verde-escura para verde-clara, tendo como base os índices de firmeza (N) e cor da casca (ºh) de 85N e 117ºh, respectivamente, em lotes uniformes, sem defeitos. Os frutos foram expostos ao 1-MCP durante 3 horas, em câmara hermética, nas concentrações de 0; 100; 300 e 900 nL.L-1 e armazenadas a 22±2 ºC e 80-85 %UR durante 12 dias. O regulador vegetal retardou a perda da cor verde da casca e da firmeza da polpa, bem como o incremento dos teores de ácido ascórbico e de sólidos solúveis, entretanto não alterou a perda de massa, a acidez titulável e a incidência de podridões. A atividade respiratória e a produção de etileno também foram influenciadas pelo 1-MCP, tendo atingido os menores valores ao empregar a maior concentração deste regulador vegetal. A aplicação de 1-MCP, nas concentrações de 300 a 900 nL.L-1, durante 3 horas, retarda o amadurecimento de goiabas 'Kumagai', prolongando sua vida pós-colheita.

The short guava shelf life is the main problem that affects commercialization of fruits, either in national or international markets. The 1-MCP is known as an ethylene blocker. This work was carried out to determine the effects of 1-MCP over attributes of quality of 'Kumagai' guavas. The guavas were harvested with the skin color changing from dark-green to light-green stage, presenting: firmness (N) 85 and skin color (h°) 117, without injuries. Fruits were exposed to 0, 100, 300, 900 nL.L-1 of 1-MCP for 3 hours. Later the fruits were kept in room temperature of 22±2 °C and 80-90 % RH for 12 days. The treatments delayed the skin color and firmness changes, and also delayed the increase of ascorbic acid and sugar; the weight loss, titratable acidity and incidence of rots were not affected. The respiratory rate and ethylene production were suppressed reaching the lowest values with the highest concentration of the product. The application of 1-MCP from 300 to 900 nL.L-1, during 3 hours, extended the shelf life of guavas 'Kumagai'.

O presente trabalho teve por objetivo estudar o efeito da benzilaminopurina e do ácido giberélico, bem como a forma de aplicação destes, na produção de brotos laterais de mamoeiro. Foram utilizados mamoeiros 'Sunrise Solo' e os reguladores vegetais benzilaminopurina (BAP) e ácido giberélico (GA), na concentração de 500 mg.L-1. As formas de aplicação de BAP + GA estudadas foram: pulverização; pasta de lanolina; injeção; completo, que consistiu na utilização de todas as formas de aplicação, e o controle, constituído pela ausência de aplicação de reguladores. Foram realizadas três aplicações semanais dos reguladores em cada forma de aplicação, sendo eliminado o meristema apical de todas as plantas após a última aplicação. O comprimento e o diâmetro dos brotos laterais foram avaliados aos 30; 55 e 86 dias após a retirada da gema apical. O uso de reguladores favoreceu a produção de brotos laterais. A pulverização apresentou os melhores resultados tanto em relação ao número de brotos obtidos quanto à conformação das estacas, seguida pela injeção e pasta de lanolina.

The aim of the present work was to evaluate the effect of 6-benzylaminopurine (BAP) and gibberellic acid (GA), as well as the form of application of these growth regulators in the plant, for the production of lateral shoots on papaya trees. Twelve months old 'Sunrise Solo' papaya trees were treated with BAP and GA, in the concentration of 500 mg.L-1. BAP + GA were applied to the trees by means of spraying, lanolin paste, injection, and a combination of all three procedures (complete). Untreated plants were used as control. After three successive applications of the plant growth regulators in each form of application, at one week intervals, all plants were decapitated. The length and diameter of the lateral shoots were measured at 30, 55 and 86 days after decapitation. The use of plant growth regulators favored the production of lateral shoots. The highest proliferation of lateral shoots was obtained by spraying the canopy of the trees with BAP + GA, followed by injection and lanolin paste applications.