Perforated Polyethylene Bags Research Articles

Modified atmosphere packaging and ethanol vapor to control decay of ‘Red Globe’ table grapes during storage

The aim of this study was to determine the efficacy of several alternative postharvest treatments to sulfur dioxide (SO 2) in maintaining quality and reducing fungal decay during cold storage of ‘Red Globe’ table grapes. Grapes were packaged in perforated polyethylene (PPE) or modified atmosphere packaging (MAP) bags (ZOEpac or Antimicrobial) with or without different grades of ethanol vapor-generating sachets (Antimold ®30, Antimold ®60 or Antimold ®80) or a SO 2-generating pad, and the grapes were kept at 0 °C and 90–95% relative humidity for 4 months. Packaging of grapes with a SO 2 pad in PPE or ZOEpac bags provided better control of fungal decay and stem browning than PPE or ZOEpac bags alone, PPE or ZOEpac bags with Antimold sachets or Antimicrobial bags alone. The PPE bag containing the Antimold ®80 sachet was as effective as the SO 2 treatments in reducing the incidence of fungal decay in naturally infected and artificially inoculated grapes for 1 month. Ethanol vapor released by the Antimold sachets enhanced berry color, but caused stem browning depending on ethanol vapor concentrations in the headspace of the bags. The ZOEpac-210 bags alone resulted in significantly lower weight loss and incidence of stem browning, compared to other treatments; however, they did not reduce fungal decay or develop an appreciable level of modified atmosphere.

Occurrence of a Fruit Spot Disease of Pomegranates Caused by Colletotrichum gloeosporiodes in the Prefecture of Komotini, Greece.

Pomegranate (Punica granatum L.) is an important crop in Greece. In 2010, fruits of the pomegranate cv. Wonderful, in commercial fields located in the Prefecture of Komotini in eastern Greece, were observed to have symptoms of distinct dark brown spots. The waxy acervuli observed in infected tissue were subepidermal, typically with setae and simple, short, erect conidiophores. Conidia were hyaline, one celled, ovoid to oblong, slightly curved or dumbbell shaped, and 10 to 15 μm long and 5 to 7 μm wide. The pathogen was isolated on acidified potato dextrose agar (PDA) (2.5 ml of 85% lactic acid per liter of nutrient medium) and incubated at 23°C for 7 days. The pathogen was identified as Colletotrichum gloeosporiodes (Penz) Sacc. on the basis of morphological characteristics and internal transcribed spacer (ITS) sequence (100% identity to AJ301912, C. gloeosporioides species complex) (3) by CBS Fungal Biodiversity Centre, Identification Service, Utrecht, the Netherlands, (CG-1 isolate deposited in CBS Collection; Accession No. CBS 129372). Koch's postulates were completed in the laboratory by placing a 40-μl drop of suspension (4 × 105 conidia ml-1 of water) on a wounded area of healthy fruits of cv. Wonderful. Fruits were surface sterilized by dipping in 0.1% chlorine solution and allowed to dry in a laminar flow hood. There were 15 inoculated and 15 control fruits (similarly sprayed with sterile distilled water) in a randomized design. Fruits were covered with perforated polythene bags to maintain a high humidity necessary for infection that were removed 48 h after inoculation and the fruits were maintained at room temperature (23 ± 2°C). Lesion development was recorded daily for each fruit. Koch's postulates were satisfied after reisolating the fungus from inoculated fruit that developed symptoms similar to those observed on fruits collected from fields. To our knowledge, this is the first report of the occurrence of C. gloeosporioides as a causal agent of fruit spot of pomegranates in Greece. Fruit spots caused by C. gloeosporioides have been reported in pomegranate fields of other countries around the world (1,2).

ABSCISSION OF SWEET BASIL LEAVES INDUCED BY ETHYLENE UNDER MODIFIED ATMOSPHERE PACKAGING

Sweet basil (Ocimum basilicum L.) is an aromatic culinary herb used for flavour addition and decoration in many foods and drinks. A crucial postharvest problem of sweet basil is short shelf life due to water loss and abscission of leaves. Sweet basil branches were packed in 60 μm polyethylene (PE) bags (20x45 cm dimension) and stored at 13°C and 95% RH. The number of abscised leaves was highest in sealed PE bags containing an initial concentration of 2500 ppm ethylene lowest in sealed PE bags containing an ethylene adsorbent. Ethylene accumulating in the bags also induced leaf abscission. Basil stored in PE bags lost less weight resulting in extended storage life compared to non-packed branches. Packing basil in non-perforated PE bags resulted in decay after 6 days. Perforated PE bags with 16 holes (12.56 cm 2 /bag) provided the best condition in maintaining the quality of basil for 9 days.

SEED GERMINATION, SEEDLING GROWTH AND VIGOUR OF PAPAYA UNDER NORTH EAST INDIAN CONDITION

Papaya (Carica papaya L.) is a popular fruit of tropics and subtropics of the world. India is in the forefront of papaya producing nations. Papaya nursery is normally raised through seeds. There are improved varieties of papaya which are being used for commercial cultivation through out the country. But none of the varieties are commercially grown in the north eastern India due to undulating topography, high rainfall, poor transport, marketing facility etc. Hence, the present study was pursued in papaya with the objective of identifying cultivars suitable to north eastern region of India with better germination percentage, seedling growth and vigour. The experiment was executed at the Horticulture division of ICAR Research Complex for NEH Region, Barapani, Meghalaya during 2001-2002 with fourteen papaya cultivars comprising varieties and hybrids of red and yellow flesh types gathered from across the world. The indigenous collections comprised cultivars from Tamil Nadu Agriculture University, Coimbatore (Co-1, Co-2, Co-3 Co-4, Co-5, Co-6, and Co-7), cultivars from G.B. Pant University of Agriculture and Technology, Pant Nagar (Pant Papaya), Indian Agriculture Research Institute, New Delhi (Pusa Dwarf) and Indian Institute of Horticultural Research, Bangalore (Coorg Honey Dew and Pink Flesh Sweet) whereas Sunrise Solo, Thailand and Washington were the other varieties from foreign sources. The seeds were soaked overnight in different concentrations of gibberellic acid (0, 50, 100, and 150 ppm) and sown in perforated polythene bags containing potting mixture. The cultivars differed significantly with respect to their 1000 seed weight, seed germination, time taken for seed germination, seedling length including seedling vigour. Soaking the seeds with GA 3 had a significant effect in improving the germination percentage of papaya cultivars. Increasing the GA 3 concentration from 0 to 100 ppm significantly improved the germination (66.17%) over the control (42.40%) and above 100 ppm the seed germination decreased. GA 3 treatment had a favorable effect in hastening the germination of papaya and the time taken for germination was maximum in untreated control (31.86 days) whereas GA 3 at 100 ppm recorded the minimum period for germination (29.73 days). GA 3 treatment had a significant effect in enhancing the seedling length and it was maximum with GA 3 100 ppm (17.38 cm) as against control recording only 10.98 cm. It is concluded that the papaya varieties viz., Coorg Honey Dew, Pant Papaya, Co-2 and Co-7 possess better seed germination, seedling growth and vigour are highly suitable for commercial cultivation in north eastern region of India and their germination and seedling health can be improved by treating with GA 3 100 ppm.

Effects of postharvest ethanol vapor treatment on activities and gene expression of chlorophyll catabolic enzymes in broccoli florets

Postharvest yellowing of broccoli ( Brassica oleracea L. Italica Group) is an important indicator of quality deterioration and occurs with chlorophyll (Chl) degradation. Postharvest ethanol vapor treatment could delay the yellowing of broccoli florets, through the suppression of Chl degradation. As the first step in identifying the mechanism of this delay, the effects of postharvest ethanol vapor treatment on activities and gene expression of the Chl catabolic enzymes in broccoli were determined. Broccoli branchlets were placed in a perforated polyethylene bag with or without (control) an ethanol pad and stored at 20 °C in darkness. The Chl contents of the control broccoli florets decreased remarkably after three days in storage, whereas the contents of the ethanol-treated broccoli showed no significant changes except at day one. Changes in chlorophyllase activity in the ethanol-treated broccoli were similar to those of the control until three days in storage, but then the activity tended to decease. Mg-dechelatase and Chl-degrading peroxidase activities, which increased greatly with senescence in the controls, remained unchanged in the ethanol-treated broccoli. BoCLH1 expression showed changes almost similar to those of chlorophyllase activity. BoPAO expression in the control broccoli increased greatly at day one in storage and was maintained at a high level until three days. In contrast, this expression in ethanol-treated broccoli was suppressed until two days. BoRCCR expression in the control broccoli increased until two days in storage, while the expression in the ethanol-treated broccoli showed no change during storage. These results show that postharvest ethanol vapor treatment suppressed the activities and gene expression of Chl catabolic enzymes, resulting in delayed yellowing of broccoli florets.

Effects of postharvest ethanol vapor treatment on ethylene responsiveness in broccoli

Broccoli ( Brassica oleracea L. Italica Group) senesces very rapidly at room temperature after harvest. Ethanol vapor treatment with ethanol pads inhibits ethylene production and prolongs the shelf-life of harvested broccoli. The effects of postharvest ethanol vapor treatment on ethylene responsiveness in broccoli were investigated to clarify the mechanism of the inhibition of senescence with ethanol treatment and develop applications for ethanol pads. Broccoli branchlets were packed in a perforated polyethylene bag with or without ethanol pads and were continuously exposed to ethylene or not at 20 °C in darkness. Exogenous ethylene accelerated the yellowing of florets and stimulated ethylene and respiration climacteric patterns. These ethylene responses were inhibited by ethanol vapor treatment. Stimulation of the activities of 1-aminocyclopropane-1-carboxylic acid (ACC) synthase and ACC oxidase and induction of the expression of BO-ACO1, BO-ACO2, and BO-ACS1 by exogenous ethylene were suppressed by ethanol vapor treatment. These results show that postharvest ethanol vapor treatment inhibits the senescence of harvested broccoli through the suppression of ethylene responsiveness as well as ethylene biosynthesis.

Effects of postharvest ethanol vapor treatment on the ascorbate–glutathione cycle in broccoli florets

Broccoli ( Brassica oleracea L. Italica Group) senesces very rapidly at room temperature after harvest. Ethanol vapor treatment suppresses the senescence. Reactive oxygen species (ROS) are closely related with postharvest quality of horticultural crops, and the ascorbate–glutathione cycle plays a crucial role in controlling the level of ROS. The effects of postharvest ethanol vapor treatment on the cycle in broccoli florets were investigated to clarify the inhibition of senescence with ethanol. Broccoli branchlets were packed in a perforated polyethylene bag with or without a 3 g ethanol pad and stored at 20 °C in darkness. The ethanol concentrations in the atmosphere of the bag containing the ethanol pad were about 40 pmol mL −1. In control and ethanol-treated broccoli, the contents of l-ascorbic acid and reduced glutathione decreased during storage, but the decrease in control broccoli was more marked than that in ethanol-treated broccoli. The ascorbate peroxidase activities in ethanol-treated broccoli were constant during storage, whereas the activities in the control broccoli decreased almost linearly. The glutathione reductase activities in ethanol-treated broccoli were higher than those in the control at 5 d in storage (DIS). The dehydroascorbate reductase activities in ethanol-treated broccoli decreased gradually. On the other hand, the activities in the control broccoli decreased gradually until 3 DIS and then considerably. These results suggest that ethanol vapor treatment might suppress the decrease in reducing substances and enzyme activities associated with the ascorbate–glutathione cycle to reduce oxidative stress through effective removal of hydrogen peroxide, and the suppression might partly contribute to the suppression of senescence in ethanol vapor-treated broccoli.

PHYSIOLOGICAL STUDY OF THE STRATIFICATION EFFECT ON THE DYNAMIC CHANGES IN ENDOGENOUS ABSCISIC ACID IN BITTER ALMOND SEEDS (Prunus amygdalus L.) AND ITS RELATION TO SEEDS GERMINATION.

Endogenous concentrations of free and bound abscisic acid (ABA) in bitter almond seeds Badam variety (local variety) from Sulaimania orchards Prunus amygdalus L. were determined by TLC and HPLC during various periods of cold stratification (0,15,30,45, and 60 days) and the germination was investigated at the Plant Hormones Laboratory in the Department of Plant Production, Faculty of Agriculture, University of Jordan, Amman, Jordan, during the period 2004 to 2005. The results indicated that cold stratification (at 5 oC using perforated polyethylene bags filled with moistened perlite) significantly reduced abscisic acid (ABA) contents of the seeds and their endocarps. A sharp significantly decline in ABA was observed during the first 15 days, especially in 45 days, after that the decline was completely decreased. The reduction in the level of ABA during stratification was associated with significantly increased germination percentage especially for 45 days (85.133 %).

Conservação de tangerina cv. <em>Clemenules</em> utilizando diferentes recobrimentos

The aim of this work was to evaluate the effects of different cuticles and storage periods on the conservation of mandarins cv. Clemenules . After harvest the fruits were kept at 5oC during 12 hours. Then, they were submitted to the following treatments: T1) control; T2) micro perforated polyethylene bag; T3) non-perforated polyethylene bag; T4) carnauba wax at 50% in water; T5) carnauba wax at 100% (without dilution). The mandarins were stored for 20, 40 and 60 days at 5oC and 90-95% RH. After that, they were kept at 15±1oC and 75-80% RH, during four days of market simulation. At harvest and after the storage periods, followed by the market simulation, the following variables were evaluated: weight loss; color; soluble solids (SS); titratable acidity (TA); SS/TA ratio; rottenness; physiological disorders and sensorial characteristics. The atmosphere modification reduced weight loss, physiological disorders and fruit rottenness of mandarins ‘Clemenules’ during storage. The fruits conditioned either in non-perforated polyethylene film or with not diluted wax showed strange flavor and lower general quality. Results showed that mandarins ‘Clemenules’, conditioned in both micro perforated polyethylene bag and carnauba wax at 50% in water, can be stored without compromising the sensorial quality, during 60 days at 5oC and kept during four days at 15±1oC to commercialization.

Effect of packaging materials on weight loss and nutrient quality changes of rechanded sweet potatoes (<i>Ipomoea batatas</i> Poir) during short-term storage

The effects of packaging materials on weight loss and nutrient quality changes of recharged submerged in clean tap water) sweet potatoes ( Ipomoea batatas Poir) roots during storage were determined. Sweet potatoes from two genotypes, ‘KEMB 10\' and ‘Yanshu\' were recharged for 14 hours and packaged in perforated polyethylene bags (0.02 mm), Kraft paper bags (0.025 mm) and nylon gunnysacks, with roots placed on open plate as control. The packages were then stored at prevailing ambient conditions (23 &#177 2 oC, 77.5 &#177 5.5 % relative humidity (RH)) for 21 days. During storage the sweet potatoes\' change in weight was determined every 3 days. Change in reduced ascorbic acid, &#223-carotene, total sugars and total soluble solids contents were determined every 7 days. There was a significant (p &#8804 0.05) weight loss as well as reduced ascorbic acid loss, but total sugars and &#223-carotene contents increased during storage. Although total sugars showed an apparent gradual increase in all packages and genotypes during storage, the increase was not significant (p &#8804 0.05). Perforated polyethylene bags significantly (p &#8804 0.05) prevented weight loss (up to 1.8 %) as well as allowed for the most retention in reduced ascorbic acid (13.45 g/100 g fresh weight), and increase in &#223-carotene (4.9 mg/100 g fresh weight) and total sugar (6.4 g/100 g dry weight) contents than Kraft paper bags and nylon gunnysacks. Roots packaged in Kraft paper bags were not different in weight and nutrient quality changes from those packaged in nylon gunnysacks. The control sweet potatoes always showed the highest losses in weight (up to 27.8 %) and nutrient quality. Packaging materials did not affect total soluble solids content during storage. The results show that packaging in perforated polyethylene bags can improve shelf life of recharged sweet potatoes by 14 days. Keywords: Ipomoea batatas ; packaging; weight loss JAGST Vol 6(1) 2004: 29-47

INFLUENCE OF REFRIGERATED STORAGE ON THE QUALITY AND SHELF LIFE OF ´HABANERO´ CHILI PEPPERS (CAPSICUM CHINENSE JACQ.)

Hot chili peppers are used in a number of commercial food and industrial applications. 'Habanero' chili pepper (Capsicum chinense Jacq.) from the Yucatan Peninsula is known for its distinctive, very hot flavor; a result of the region's climate and soil conditions. A study was done of the effect of ripeness stage at harvest and refrigerated storage on 'Habanero' chili shelf life and quality characteristics. Pepper fruit were harvested at three ripeness stages: green; green ripe; and beginning changing to orange. Samples of all three stages were stored at room temperature (22°C) and evaluations made of quality changes to the fruit during a 15-day period. Ripe green peppers were stored at 7°C over a 35-day period in perforated polyethylene bags. Samples were taken periodically, left to ripen at 22°C and evaluations made of general appearance, weight loss, acidity, vitamin C content, skin color, firmness and total capsaicinoid content. Results indicate that optimum ripeness stage for harvest is green ripe as the peppers develop enhanced quality characteristics and have a longer, 10-day, shelf life at 22°C. Peak 'Habanero' chili quality under storage conditions was attained using refrigeration of green ripe fruits for 20 days followed by ripening for 5 days at 22°C.

Effect of Pretreatment of Intact `Gala' Apple with Ethanol Vapor, Heat, or 1-Methylcyclopropene on Quality and Shelf Life of Fresh-cut Slices

`Gala' apples [Malus silvestris (L.) var. domestica (Borkh.) Mansf.] were treated with ethanol vapor (5 mL·kg-1 fruit for 24 hours at 25 °C), heat (4 days at 38 °C and >98% RH), or 1-methylcyclopropene (1-MCP; 1 or 0.625 μL·L-1 for 18 hours at 20 °C) before processing into slices, then dipped in anti-browning solutions or coatings, drained, and packaged in perforated polyethylene bags. Residual effects of pretreatments on fresh-cut slice physiological and quality attributes were investigated during storage for up to 19 days at 5.5 °C. Ethylene production was reduced by ethanol, heat, and 1-MCP pretreatments, while ethanol and heat also reduced slice respiration. Heat and 1-MCP pretreatments inhibited slice texture changes, while ethanol had no effect on instrumental texture measurements but reduced sensory firmness. Ethanol pretreatment increased the contents of ethanol and ethyl esters in slices but reduced acidity, while heat reduced both acidity and aroma volatile levels. Both ethanol and heat pretreatments led to lower sensory scores for apple flavor and ethanol-pretreated slices also received higher scores for altered flavor, although all scores were in the acceptable range. Slice acidity was best maintained by 1-MCP pretreatment. Shelf life based on appearance was 15 to 16 days for ethanol-pretreated slices and 12 days for heat-pretreated slices compared to that of control, which was 8 to 9 days, while 1-MCP pretreatment promoted decay development on the cut surface, which reduced the shelf life to 7 to 8 days. Obvious separations were determined between ethanol- and heat-pretreated slices and untreated control by canonical discriminant analysis of headspace volatile levels determined by GC and electronic nose. Therefore, pretreatments with ethanol and heat are very effective for prolonging visual shelf life at the expense of aroma quality.

FRUIT SET SUCCESS OF THREE MANGO (MANGIFERA INDICA L.) CULTIVARS USING RECIPROCAL CROSSES

'Tommy Atkins' has general characteristics of tall trees, fruit with red blush skin and fair taste. It has reasonable anthracnose resistance, but is highly susceptible to mango malformation. Indian cultivars Amrapali and Mallika are small trees with sweet fruits, but their yellow skin color has low market acceptance. Due to their good characteristics for mango breeding, these cultivars have been used in hybridization studies, but their general combining ability - GCA for fruit set is still unknown. To support future crosses, an experiment was carried out at Embrapa Cerrados, in Brasilia, to study fruit set success or compatibility among these three cultivars. A completely randomized design with six treatments or crosses ('Mallika' x 'Tommy Atkins'; 'Tommy Atkins' 'Mallika'; 'Mallika' x 'Amrapali'; 'Amrapali' x 'Mallika'; 'Tommy Atkins' x 'Amrapali'; 'Amrapali' x 'Tommy Atkins') and five replications (panicles) were used. Opened flowers were discarded from healthy panicles, which were protected by perforated polyethylene bags. In the morning, young and still closed buds were removed, opened flowers were selected, emasculated and hand pollinated using anther of male progenitor. The panicles were bagged and tagged. Fruit set was studied weekly for six weeks. 'Mallika' had the lowest compatibility rate and 'Amrapali' x 'Tommy Atkins' had the best fruit set with 16.1% success.

ASSESSMENT OF SIX STORAGE METHODS FOR SEED POTATO STORAGE IN NIGERIA

Studies were carried out in 1997 and 1998 at Kuru, Jos Plateau, Nigeria to assess six storage methods for the storage of seed potato. The methods were: Storage in jute bags, perforated polythene bags, baskets, racks, crates and floor. Potato varieties used were Nicola (medium to long dormancy) and B7716-2 (short dormancy). The seed tubers were stored for six months during which daily maximum and minimum temperatures of the storage environment, and the relative humidity were recorded. Tuber weight loss, loss due to rots, sprout number and length per tuber at the end of the storage were also recorded. Results showed that only polythene bag reduced tuber weight loss, but resulted in highest tuber rots due to soft rot disease of potato. Poor light condition in jute bags encouraged the development of long and etiolated sprouts of seed potato. Sprout number per tuber was not affected by the storage methods. Varietal differences in tuber weight loss, sprout number and tuber rots were significant (P≤ 0.05). Due to dehydration, tuber weight loss increased by 37 percent during the six months storage. Based on the results obtained, storage is recommended in crates, racks and on floor of well-ventilated stores for short-term (4 months) storage, since these methods provided good ventilation of stored seed and tuber rots are low. [Niger Agric. J. 34 (2003): 91-96]

Shelf-life and quality of ber (Ziziphus mauritiana Lamk) fruits after postharvest water dipping treatments and storage

SummaryAn experiment was conducted to study the effect of postharvest water dipping treatments and storage conditions on shelf life and quality of ber (Ziziphus mauritianaLamk). Fresh fruits of ber ‘Umran ’ were dipped in either cold (128C) or hot (50˚C) water for 5 min and packed under different storage containers i.e. corrugated fibre board boxes, sealed polythene bags and perforated polythene bags. Control fruits were packed without dipping treatment. Result showed that postharvest water dipping at 508C for 5 min significantly increased the shelf life and maintained the quality of ber fruits, particularly late in the storage period. Fruits packed in sealed polythene bags significantly lowered the loss in fruit weight, spoilage and ripening with consequent increase in acidity and organoleptic score. Interactive results showed that hot-water treated fruits stored in modified atmospheric bags (sealed polythene bags) were qualitatively better than control fruits in terms of colour, taste and appearance. The organoleptic score reveals the acceptability of these fruits even after day 8 of storage. The control fruits were not found acceptable after day 4 of storage. It is suggested that postharvest fruit dipping in hot water (508C) forfive minutes followed by packaging in sealed polythene bags can enhance the shelf life and quality of ber fruits.

Delay of Fruit Softening in Forcing-cultured 'Tonewase' Japanese Persimmon by Packaging in Perforated Polyethylene Bags

'Tonewase' is an early maturity strain selected from 'Hiratanenashi', an astringent Japanese persimmon cultivar. In some districts of Japan, 'Tonewase' has been grown under forcing-culture conditions, which often results in rapid softening during postharvest distribution. In this study, we elucidated that this softening is caused by water-stress-induced ethylene that can be suppressed by reducing water loss by using perforated polyethylene bags (PPB). With or without removal of astringency by treatment with elevated carbon dioxide (CTSD method), forcing-cultured 'Tonewase' fruit produced significant amounts of ethylene two days after harvest ; thereafter, most fruit softened rapidly. This softening was markedly suppressed by treating the fruit with 1-methylcyclopropene (MCP), an inhibitor of ethylene action, which suggests the involvement of ethylene in fruit softening. Packaging 'Tonewase' fruit in PPB ranging from 0.03% to 0.3% of the total film surface area reduced water loss, retarded the commencement of ethylene production and delayed fruit softening. Immature field-grown 'Hiratanenashi' fruit behaved similarly to the forcing-cultured 'Tonewase' fruit with respect to ethylene production, softening and response to MCP treatment and PPB, whereas mature fruit under the same storage conditions produced no ethylene and remained firm during postharvest.

Inhibition of Fruit Softening by Packaging in Perforated Polyethylene Bag at Various Storage Temperature in Forcing-cultured 'Tonewase' Japanese Persimmon Grown in Greenhouse

Inhibition of Fruit Softening by Packaging in Perforated Polyethylene Bag at Various Storage Temperature in Forcing-cultured 'Tonewase' Japanese Persimmon Grown in Greenhouse

QUALITY CHANGES OF 'LOBO' APPLES DURING COLD STORAGE

Apples of cultivar Lobo from two orchards (1 and 2) situated in the southwest of Finland were harvested either at the end of August (early harvest) or at the beginning of October predicted optimal or normal harvest), and stored at +3°C and 85% RH for three months. For reducing water evaporation from apples, they were kept in unsealed paper or unsealed, not perforated polyethylene bags. Macronutrients (N, P, K, Ca and Mg) and dry matter in fruit flesh, fruit diameter and firmness as well as soluble solids content (SSC) in juice were determined before and after the storage. The incidence of physiological storage disorders was recorded. Apples from orchard 2 were smaller in diameter and their firmness per diameter was higher, whereas dry matter and soluble solids content were lower than in apples from orchard 1. At normal harvest time, macronutrient concentrations were higher in apples from orchard 2, and at early harvest, nitrogen and potassium were higher in apples from orchard 1. Fruit firmness per diameter, dry matter and SSC (orchard 1) were higher at normal harvest. During storage of normally harvested apples fruit firmness per diameter decreased and SSC in juice increased due to the progressive ripening process. Low or even decreasing soluble solids concentration of early-harvest apples indicated improper ripening. The dry matter increased and fruit diameter decreased because of water loss and shrivelling of apples during the storage period. The nutrient concentrations of apples also increased along with increasing dry matter content. In the early harvested apples from orchard 1, physiological disorders increased significantly during storage. Normally harvested apples stored in polyethylene bags had higher diameter and firmness per diameter, lower dry matter, soluble solids and nutrient levels, and less physiological storage disorders than early harvested fruit.

輸入フィリピン産「Ｃａｒａｂａｏ」マンゴー果実の品質保持に関する研究

The effects of packaging 'Carabao' mangoes, imported from the Philippines in polyethylene (PE) bags, with and without perforations, and kept at 20°C, were investigated. Their appearance, using a 6-point numerical peel color index (PCI), sugar and organic acid contents, and their tendency to shrivel were assesed. 1. Portions of the peel still remained greenish after day 7 in PE20 bag although fruit maturities, which were ranked as PCI-2 and PCI-3 initially, advanced to PCI-4 and PCI-5, respectively. The Hunter, a value which increased in both the peel and flesh with time, was smaller in the fruit packaged in PE20 bag than it was in unpackaged fruits (control) of those packaged in the perforated PE bag. 2. Starch content in PCI-2 fruit was higher level than that in PCI3 but it rapidly decreased in the first day of storage. Sucrose was a predominant sugar in 'Carabao' mangoes. The total sugar, sucrose, and fructose contents increased during storage. The tendency for sugar to increase was slower in the fruit in PE20 bag than in the others. Sugar content in PCI-2 fruit in perforated or PE20 bags were lower than that in PCI-3 fruits. Glucose content decreased in the control or perforated PE bag faster than it did in fruits in the PE20 bag. 3. Citric acid which is the predominant organic acid in 'Carabao' mangoes was initially higher in fruits at stage PCI-2 than in those of PCI-3 ; it decreased during storage. The tendency for citric acid to decrease in fruit in the PE20 bag was slower, but its level was similar to fruits of the control and perforated PE20 bags. Malic and succinic acids were also found in 'Carabao' mangoes but remained at a low level during storage. 4. Shrivelling, which occurred in the peel of PCI-2 and -3 fruits, began on day 5 in control fruits and on day 7 in perforated PE bags, at which time the water loss was about 7%. Shrivelling did not occur in fruits in PE20 bags at both stages PCI-2 or -3. 5. Packaging PCI-3 fruits in perforated PE bags did not prevent increases in sugars, decreases in organic acids, nor advancement in flesh and peel color or water loss as compared with those of PCI-2. Thus, we recommend that imported 'Carabao' mango fruits at PCI-3 be packages in perforated PE bags because they were most effective in maintaining quality.

Influence of Bulb Packing Systems on Forcing of Dutch-grown Hippeastrum (Amaryllis) as Flowering Potted Plants in North America

Dutch-grown Hippeastrum bulbs (`Apple Blossom' and `Red Lion') were packed in five readily available and economical packing systems and after transport and storage were evaluated as flowering potted plants. After being harvested and graded, bulbs were specially packed and placed in perforated cardboard boxes, shipped by boat to Raleigh, N.C., and stored in the original packing materials for 84 days at 48 °F (9 °C). At planting time, the best old basal root system and lowest disease incidence for both cultivars was obtained when bulbs were packed with hout-wol, a type of excelsior, in perforated polyethylene bags and placed in perforated cardboard boxes. Plants from bulbs with this system and those packed loose in polyethylene bags flowered the earliest. At full flower, the longest leaves were obtained with the hout-wol, box only, and wood chip systems. There were no significant effects of the five packing systems on floral stalk length, number of flowers produced per stalk, flower diameter, strength of the first floral stalk or leaves, or overall plant quality. After flowering, the root systems were harvested. The hout-wol packing system significantly increased the fresh weights of the old basal roots retained, secondary roots produced, and total weights of the root system. there were significant differences between cultivars. `Apple Blossom' produced fewer roots and lower quality plants (shorter leaves and taller floral stalks) than `Red Lion'. Other significant cultivar differences, e.g., days to flower, were attributed to genetic variation. Based on the most desirable forcing characteristics, the superior packing system for shipping and storing Dutch-grown Hippeastrum bulbus was hout-wol combined with perforated polyethylene bags.