Luiz Carlos Argenta

Delaying establishment of controlled atmosphere or CO2 exposure reduces 'Fuji' apple CO2 injury without excessive fruit quality loss

Abstract Storage of ‘Fuji’ apple fruit in a high CO 2 (3 kPa) and low O 2 (1.5 kPa) controlled atmosphere (CA) reduced firmness and titratable acidity (TA) loss during long term storage. This CA environment also induced development of internal CO 2 -injury (brown-heart) and slowed the disappearance of watercore. The symptoms of internal CO 2 -injury were first detected 15 days after CA establishment and the severity increased during the first 4 months of CA-storage. Delaying establishment of CA conditions for 2–12 weeks significantly reduced the severity of CO 2 -injury. Delaying CO 2 accumulation to 3 kPa for 1–4 months during CA (1.5 kPa O 2 +0.05 kPa CO 2 ) storage also reduced development of CO 2 -injury symptoms. Delaying CA or CO 2 accumulation resulted in lower firmness and TA compared to establishment of CA within 72 h of harvest. However, the delay treatments did result in firmness and TA that were significantly higher compared to values for fruit stored in air. The incidence and severity of senescent injuries (flesh browning and core flush) detected during the late period of storage were greater in air- than CA-stored fruit. The results indicate the susceptibility of ‘Fuji’ apples to CO 2 -injury is highest during the first weeks of storage after harvest. Delaying establishment of CA or exposure to elevated CO 2 after harvest may be a practical strategy to reduce CO 2 -injury while maintaining other important quality attributes at acceptable levels.

Ripening and quality of 'Laetitia' plums following harvest and cold storage as affected by inhibition of ethylene action

Abstract – The inhibition of ethylene action by 1-methylcyclopropene (1-MCP) extends shelf and storagelife of many climacteric fruits. However, 1-MCP appears to have limited effects on stone fruit dependingon specie and cultivar. The effects of 1-MCP on ripening and quality of ‘Laetitia’ plums were determinedduring ripening at 23 o C following harvest and cold storage. Japanese plums ( Prunus salicina , cv. Laetitia)were harvested at mature pre-climacteric stage, cooled to 2 o C within 36 hours of harvest and then treatedwith 0, 0.05, 0.10, 0.50 or 1.00 µL L -1 of 1-MCP at 1°C for 24 hours. Following treatment, fruits wereeither held at 23 o C for 16 days or stored at 1 o C for 50 days. Fruits were removed from cold storage at 10-day intervals and allowed to ripe at 23°C for five days. A delay of climacteric respiration and ethyleneproduction by 1-MCP treatment during ripening following harvest and cold storage was associated to aslow rate of fruit softening. 1-MCP treatment also delayed the loss of titratable acidity and changes of fleshand skin color, whereas it had little or no effect on soluble solids content. 1-MCP effects were concentration-and storage duration-dependent and, generally, a saturation fruit response to 1-MCP occurred between 0.5and 1.0 µL L

Impact of watercore on gas permeance and incidence of internal disorders in ‘Fuji’ apples

The impacts of watercore on incidence of internal disorders and other physiological characteristics of ‘Fuji’ apples (Malus domestica Borkh) were determined following short-term exposure at 20 °C in 20 kPa CO2 (high pCO2 )o r long-term storage at 0.5 °C in 0.5 kPa O2+0.05 kPa CO2 (low pCO2) or 1.5 kPa O2 + 3 kPa CO2 (medium pCO2). CO2-injury (brown-heart) occurred in apples exposed to high pCO2 or medium pCO2, but no internal disorders were observed in fruit held at 20 °C in air or 4 months at 0.5 °C in low pCO2, regardless of watercore severity at harvest. Depending on harvest date and orchard, the severity of CO2-injury was significantly correlated with watercore severity. Watercored tissue has a lower intercellular air space volume, reduced permeance to gas diffusion and increased internal pCO2. Accumulation of ethanol and acetaldehyde occurred in watercored ‘Fuji’ apples even under ambient (21 kPa O2) conditions and this accumulation increased with watercore severity regardless of storage environment.

Influência da temperatura de armazenamento na qualidade pós-colheita de goiabas serranas

This study was carried out to evaluate the storage potential of feijoas at temperatures of 23 oC and 4 oC. Fruit were harvested in a commercial orchard in Sao Joaquim, SC, and stored at 23 ± 1 oC (75±5% RH, for 15 days) and 4 ± 1 oC (90±5% RH, for 4 weeks). Fruit were assessed during storage in terms of respiration and ethylene production rates, soluble solids content (SSC), titratable acidity (TA), skin color (hue angle; ho), and incidence of flesh and skin browning, and rots. Fruit stored at 23 oC exhibited a climacteric, reaching a peak of respiration rates between the 4th and 5th days. Fruits stored at 4 oC had lower respiration and ethylene production rates. Fruit stored at 23 oC had more substantial decreases of SSC, TA, and ho of the skin, and increases of skin browning and decay incidence, compared to fruit stored at 4 oC. The storage at 4 oC was more effective to reduce respiration and ethylene production, to preserve the quality attributes (SSC, TA, and ho of the skin), and to reduce the severity of skin browning and decay, without avoiding the development of flesh browning. The storage potential of feijoas at 23 oC is less than one week as a result of flesh browning and skin browning development and decay.

CONTROLE DA MATURAÇÃO PRÉ-COLHEITA DE MAÇÃS ‘ROYAL GALA’ PELA INIBIÇÃO DA AÇÃO OU SÍNTESE DO ETILENO

ABSTRACTThe objective of this research was to evaluate the effects of ethylene action inhibition (by sprayable formulation of 1-methylcyclopropene; 1-MCP) and ethylene synthesis inhibition (by aminoethoxyvinylglycine; AVG) on preharvest apple fruit maturation. ‘Royal Gala’ apple trees were sprayed with 1-MCP (at 50 or 100 mg L-1)) seven days before anticipated harvest (DBAH), or with AVG (124 mg L-1)) 28 DBAH. Apple trees not sprayed with 1-MCP and AVG were used as control. Fruit were harvested weekly,along five weeks from the 7th day after 1-MCP spraying, and then analyzed in terms of maturity and quality one day after harvest. Fruit maturity and quality attributes when fruit reached the flesh firmness of 71.1 N were estimated by analysis of regression, for each treatment. 1-MCP (50 and 100 mg L-1)) and AVG delayed fruit maturation, by reducing the ethylene production rates, starch degradation, loss of flesh firmness and acidity, skin yellowing, increase of soluble solids content and skin red color development. 1-MCP (100 mg L-1)) and AVG delayed in 6 and 12 days, respectively, the time required for fruit to reach the flesh firmness of 71.1 N on the tree, in comparison to the control. Fruit treated with 1-MCP or AVG had starch index, ethylene production and acidity values similar or smaller than the control, at the date when all treatments achieved the flesh firmness of 71.1 N. The magnitude of 1-MCP effect on flesh firmness was similar to the effect on ethylene production and skin color, and slightly slower on starch degradation. The effects of AVG on ethylene production, skin color and acidity were more substantial than on loss of flesh firmness. The results show that the treatment of ‘Royal Gala’ apple trees with the sprayable formulation of 1-MCP represents an additional method for management of fruit maturation and harvest.

POTENCIAIS BENEFÍCIOS DO AUMENTO DA TEMPERATURA DE ARMAZENAGEM EM ATMOSFERA CONTROLADA DE MAÇÃS ‘GALA’ TRATADAS COM 1-MCP

Cold storage can induce the development of chilling injury (characterized by internal browning) in some apple cultivars, even when fruit are kept in temperature above the freezing point. This research evaluated the increment of storage temperature for ‘Gala’ apples under controlled atmosphere (CA) and 1-methylcyclopropene (1-MCP) treatment, as a method to reduce the development of internal browning and energy consumption. Experiments were conducted in 2011, with apples produced in the regions of Fraiburgo (stored in experimental chambers at -0.3 and 1.2 °C, and in commercial chambers at 0.7 and 2 °C) and Sao Joaquim (stored in commercial chambers at 0.8, 1.4 and 1.9 °C). Fruits of all treatments were kept under CA (1.8±0.2 kPa O2 and 2.0±0.2 kPa CO2/RH of 91±4%), with half of the fruits of each storage temperature being treated with 1-MCP. The fruit were assessed in terms of flesh firmness, and incidence of internal browning, skin cracking and decay. In general, apples stored at higher temperatures had better preservation of flesh firmness, and lower incidence of internal browning, skin cracking and decay, in fruit not treated with 1-MCP. The treatment with 1-MCP delayed flesh firmness loss and reduced the occurrence of internal browning and skin cracking. In Fraiburgo, increasing the AC storage temperature from 0.7 °C to 2.0 °C resulted in energy saving of ~21% for air ventilation and of ~50 % for cooling.

DIAGNÓSTICO DA QUALIDADE DE MAÇÃS NO MERCADO VAREJISTA BRASILEIRO

The aim of this study was to evaluate the quality and price of apples in the Brazilian retailer market. Samples of Gala, Fuji and Red Delicious apples were collected monthly between March of 2010 and January of 2011 in 20 supermarkets in Curitiba, Sao Paulo, Belo Horizonte, Rio de Janeiro and Recife. Four supermarkets in each city were previously selected and defined as sources of apple samples for the 11 months of the study. The Category (scale 1 to 3) of the apples was defined by external fruit quality (color; severity of physiological, mechanical, fungus, insect and hail damage, etc) according to the legal standards of MAPA. Category 1 and 3 represent the highest and lowest fruit quality standards, respectively. The average Category of the apples in the supermarkets increased during the year from 1.6 to 2.0 for ‘Gala’, from 1.8 to 2.4 for ‘Fuji’ and from 1.4 to 1.8 for ‘Red Delicious’. The loss of quality in the period between the packing and the exposure of the fruits in the supermarket was evident in all 11 months and varieties. The decrease of the external quality in the apples at the supermarket was associated with high incidence of mechanical damages and decay that ranged between 13 to 50% and 1 to 20%, respectively, depending of the variety and the month of evaluation. The flesh firmness of the apples decreased between March and July for levels below 12 lb and tended to increase to levels close to 14 and 15 lb between November and January depending of the variety. The standards of price and quality fluctuation along the year indicate that the retail price of the apple is more influenced by the seasonality or the pressure of sales than by the quality of the fruit. The variation of apple prices among regions was similar for the three varieties. Data indicated that average period between packing and supermarket exposure is 17 and 28 days for ‘Gala’ and ‘Fuji’ apples, respectively.

EFEITO DO ENSACAMENTO NA QUALIDADE DE MAÇÃS EM DIFERENTES ESTÁDIOS DE DESENVOLVIMENTO

This study aimed to evaluate the influence of bagging on apple fruit quality on different development stages. The study was conducted in an organic orchard at the Experimental Station of Epagri in Cacador, SC, during the 2009/2010 and 2010/2011 crop seasons. The apple tree genotypes evaluated were ‘Royal Gala’, ‘Fuji Suprema’, ‘Catarina’ and the M-11/00 selection. The fruits were evaluated at the following stages: intermediate development (half-cycle), at harvest or commercial maturity and seven days after harvest. Fruits were submitted to two different conditions (treatments): bagged and no bagged. Fruits were bagged after thinning, at approximately 20 mm diameter, with white non-textured fabric packaging. The physico-chemical attributes evaluated were: background color, diameter, fresh weight, pulp firmness, starch-iodine index, titratable acidity and total soluble solids. Fruit bagging did not affect fruit background color or total soluble solids. However, fruit diameter, fresh weight, pulp firmness, starch-iodine index and tritratable acidity were altered depending on the apple tree genotype and developmental stage. Bagging can provide larger and heavier fruits, it may also anticipate maturity due to reduction on pulp firmness and increase of the starch-iodine index. In some genotypes and developmental stages the average tritratable acidity values were lower in bagged fruits.

Storage potential of ‘SCS426 Venice’ apples under different storage technologies

This study aimed to evaluate the storage potential of SCS426 Venice apples under different storage technologies. Fruits were harvested in an experimental orchard located in Fraiburgo, SC and stored for up to eight and ten months in 2013 and 2014, respectively. Apples were treated or not with methylcyclopropene (1-MCP) and stored under air atmosphere (AA, 0.5±0.5 °C/RH 85±5%) or controlled atmosphere (CA; 1.5 kPa of O2 and 1.5 kPa of CO2 at 0.7±0.5 °C/RH of 93±3%). Fruits were evaluated every two months of storage, after one and seven days of shelf life (23 ± 0.3 °C/RH 93±3%). The storage period of ‘SCS426 Venice’ apples under AA without 1-MCP application should not extend beyond six months. Under this storage condition, fruits had higher incidence of decay, ethylene production and respiratory rates, higher skin degreening, lower flesh firmness, titratable acidity and soluble solids content than fruits stored under CA or AA with 1-MCP. ‘SCS426 Venice’ apples develop flesh browning and superficial scald after longterm storage. ‘SCS426 Venice’ apples under AA treated with 1-MCP or under CA (regardless of 1-MCP application) can be stored for more than eight months, keeping flesh firmness above 14 lb and low incidence of physiological disorders even after ten months of storage.

EFFECT OF THIDIAZURON CONCENTRATION AND APPLICATION PERIOD ON ‘ROYAL GALA’ APPLE FRUITING AND PRODUCTION

ABSTRACT ? ?Gala? apple trees have low fruit set in restrictive pollination situations, being an obstacle to the achievement of high production rates in orchards in southern Brazil, which can be minimized by the use of growth regulators. The aim of this study was to evaluate the effect of thidiazuron concentrations in ?Royal Gala? apple fruiting and production, grown in mild winter conditions. The experiment was conducted during the 2011/2012, 2012/2013 and 2013/2014 crop years in Fraiburgo, SC, on ?Royal Gala? apple trees in Marubakaido rootstock M9 with filter. In all evaluation cycles, the experimental design was a randomized block with factorial arrangement (6x2) with six TDZ concentrations and two application forms, with six replicates, and the experimental unit consisting of one plant. The TDZ concentrations of each treatment were applied split into two seasons. The first application was performed on pink bud stage (E2) and the second application was in full bloom stage (F2). The variables evaluated were: fruit set (%), return bloom (%), number and weight of fruits per plant, mean fruit weight (g) and average number of seeds per fruit. Data were submitted to analysis of variance, in which for significant variables by the F test, analysis of contrast and polynomial regression were performed in order to evaluate the response of variables with increasing TDZ concentration. TDZ is effective even at low concentrations, increasing the production and fruit set of ?Gala? apples in the climatic conditions of southern Brazil. Index terms: Malus domestica Borkh., growth regulators, cytokinin, fruit set.