Postharvest Longevity Research Articles

Blueberry Producers’ Attitudes toward Harvest Mechanization for Fresh Market

The availability and cost of agricultural labor is constraining the specialty crop industry throughout the United States. Most soft fruits destined for the fresh market are fragile and are usually hand harvested to maintain optimal quality and postharvest longevity. However, because of labor shortages, machine harvest options are being explored out of necessity. A survey on machine harvest of blueberries (Vaccinium sp.) for fresh market was conducted in 2015 and 2016 in seven U.S. states and one Canadian province. Survey respondents totaled 223 blueberry producers of various production sizes and scope. A majority (61%) indicated that their berries were destined for fresh markets with 33% machine harvested for this purpose. Eighty percent said that they thought fruit quality was the limiting factor for machine-harvested blueberries destined for fresh markets. Many producers had used mechanized harvesters, but their experience varied greatly. Just less than half (47%) used mechanical harvesters for fewer than 5 years. Most respondents indicated that labor was a primary concern, as well as competing markets and weather. New technologies that reduce harvesting constraints, such as improvements to harvest machinery and packing lines, were of interest to most respondents. Forty-five percent stated they would be interested in using a modified harvest-aid platform with handheld shaking devices if it is viable (i.e., fruit quality and picking efficiency is maintained and the practice is cost effective). Overall, the survey showed that blueberry producers have great concerns with labor costs and availability and are open to exploring mechanization as a way to mitigate the need for hand-harvest labor.

Ultrasonic fog application of organic acids delays postharvest decay in red bayberry

Red bayberry (Morella rubra Lour.) has attractive fruit with appealing flavour and global market potential. However, its fresh fruit are highly susceptible to mechanical damage and postharvest fungal decay. The objective of the current study was to assess the efficacy of weak organic acids in delaying decay when applied to the fruit as an ultrasonic fog. Preliminary screening identified genotypes with acceptable postharvest longevity for use in the experiments. Fruit of genotype N1MR06 that received a 1h ultrasonic fog treatment with acetic acid exhibited a significantly (P<0.05) lower decay incidence of 18% after 10 d at 5°C as compared with 70% for untreated control fruit. However, the decay incidence in fruit treated with citric acid (55%) did not significantly (P>0.05) differ from the control. Subsequent experiments using fruit of genotypes N1MR06 and N1MR09 confirmed that ultrasonic fogging with acetic acid was an effective measure for delaying postharvest decay in red bayberry. Sensory evaluation along with total soluble solids and titratable acidity measurements showed that the acetic acid treatment had no adverse effect on the organoleptic quality of red bayberry. Overall, the study determined that genotype selection has an impact on red bayberry shelf life and that further shelf life gains can be achieved through ultrasonic fogging of safe, natural and inexpensive acetic acid.

The effect of preservatives on water balance in cut clematis flowers

ABSTRACTA positive water balance is crucial for longevity of cut shoots. When water loss by transpiration exceeds water uptake by cut flowers, wilting symptoms appear. Clematis is a very attractive plant which can be used as a cut flower provided that suitable cultivars are chosen. The vase life of four cultivars tested ranged between 6.7 days and 9.0 days and the standard preservative – 200 mg·dm−3 8-hydroxyquinoline citrate (8HQC) plus 2% sucrose – prolonged it significantly in two cultivars, while 8HQC alone was efficient in only one. The preservatives delayed reduction in fresh weight. An enhancement of water uptake by the preservatives resulted in prolonged vase life of flowers in two cultivars. However, the effect of preservatives on transpiration was not related to longevity. In addition, longevity did not depend on the xylem vessel size: the cultivar with the longest vase life had the lowest average xylem vessel diameter while the cultivar with the largest vessels had an intermediate vase life. Preservatives did not always affect the number of blockages in xylem appearing during vase life. Generally, the effects of preservatives on the elements of water balance in cut shoots of clematis were not directly related to the postharvest longevity.

Water relations in post-harvested torch ginger affected by harvest point and carnauba wax

The use of post-harvest techniques that enhance quality and longevity of cut flowers is essential for successful marketing. However, for some species the most appropriate procedures are still unknown. The aim of this work was to evaluate the storability and post-harvest quality of flower stems of torch ginger harvested at two stages of flower opening, treated or not with carnauba wax, and stored at 16 or 21°C. Carnauba wax (0, 0.75, 1.5 and 3.0% w/v) was applied to flowers at two stages of opening (semi-open and open bracts). Evaluations were performed every other day for 20 d. Visual quality was analysed by means of a grading scale; and relative fresh weight, water absorption, transpiration, water balance and bract anatomy were assessed. Carnauba wax was deposited as epicuticular sheets, but its application had no effect on the physiological or visual quality of the floral stems. Semi-open stage provided better visual quality for a larger number of days during the tested period of storage, along with physiological responses that contributed to the improvement of post-harvest longevity.

Evaluation of potential use of native Anthurium foliage

The Brazilian flora has a large number of species with ornamental potential. These species are poorly recognized or even completely unexplored. The objective of this study was to evaluate the potential use of four accessions belonging to the species of Anthurium plowmanii, A. raimundii, A. bonplandii and A. Affine for cutting foliage. The accessions from Embrapa Germplasm Bank of Tropical flowers were evaluated for 21 morphological and phenological characteristics and post-harvest longevity. The ornamental characterization was based on the evaluation of this data and florist acceptance as well. The accessions presented differences in almost all the characteristics related to the morphology of the inflorescence and the leaf. Some characteristics such: fruit color, petiole, spadix, and spathe length, are highly variable within the species and depend on the developmental stage. Some characters like petiole length and inflorescence position are particularly important as indicators for the use as cut foliage. The plants have slow development as typical from members of this family and and the production of leaves per year ranged between 6.6 (A. plowmanii) to 10.5 (A. bonplandii), which might be increased with the improvement of cultivation aspects, with an emphasis on spacing, plant management and fertilization. The leaves of Anthurium plowmanii, A. raimundii, A. bonplandii and A. affine present high postharvest durability and great potential as cut foliage, possessing florist acceptance as well.

Postharvest Longevity of Cut Gerbera and Alstroemeria as Affected by Citric Acid Pulse and Vase Solutions

End-user vase life of two popular cut flowers, gerbera (Gerbera jamesonii) and alstroemeria (Alstroemeria spp.) is limited due to non-adoption of appropriate postharvest treatments in Sri Lanka. Citric acid-based cut flower preservatives could be affordable treatments to extend the longevity of those species. Therefore, a study was carried out to investigate the effectiveness of pulse and vase solution treatments with citric acid for increasing the keeping quality of cut gerbera and alstroemeria flowers. For pulsing, cut flower stems were treated with 0 mM (distilled water), 5, 10 and 15 mM citric acid combined with 5, 16 and 24 h pulsing durations. Only alstroemeria was further tested with 0, 15, 25 and 30 mM citric acid with previous pulsing durations. Pulsed stems were stood into distilled water for vase life evaluation. For vase solution treatment, citric acid at 0, 1, 2, 5 and 10 mM concentrations were incorporated in vase water. In the next step, two levels of citric acid (0, 1 mM) were combined with four levels of sucrose (0, 1, 2, 5%) in vase water for gerbera. Factorial experiments were arranged in completely randomized design with five to ten replicates. Data on vase life, relative fresh weight and solution uptake rate were recorded. Pulse treatments were ineffective for improving vase life. Nevertheless, a vase solution with 1 mM citric acid showed a 2-fold increase in vase life and a better retention of fresh weight in cut gerbera. Incorporation of citric acid in vase water did not extend the vase life of cut alstroemeria flowers. Combining citric acid with sugar in the vase solution maintained favourable relative fresh weight, water uptake rates and vase life in cut gerbera. Thus, incorporation of 1 mM citric acid and 1 – 2 % sugar in vase or holding solutions could improve the longevity of cut gerbera flowers.

The effect of growth regulators on post-harvest Alchemilla mollis (Bauser) Rothm. leaf longevity

Abstract Leaves of Alchemilla mollis (Bauser) Rothm. were the subject of the study. The leaves were harvested early in the morning from the department’s ornamental plant collection. Selected leaves were fully-developed and showed no signs of damage or discolouring. Gibberellic acid (GA3), benzyladenine (BA), meta-methoxytopolin (MemT) and its riboside (MemTR) at concentrations of 25, 50 and 75 mg dm−3 were applied in the form of solutions to four-hour leaf-conditioning in the room at a temperature of 18-20°C. After conditioning, the leaves were placed in distilled water. Leaves put into distilled water immediately after cutting served as the control. The post-harvest longevity of leaves of Alchemilla mollis was 7.2-11.8 days. The conditioning of leaves in gibberellic acid solutions at concentrations of 25-50 mg dm−3, benzyladenine at concentrations of 25 mg dm−3 and meta-methoxytopolin and its riboside at concentrations of 75 mg dm−3 extended the post-harvest longevity of leaves by 10.1-81.9%. The conditioning of leaves in gibberellic acid at a concentration of 50 mg dm−3 inhibited the degradation of chlorophyll, as indicated by the highest SPAD index values.

Longevidade de hastes florais de Oncidium baueri mantidas em soluções conservantes

Orchids have been gaining prominence in the cut flower market due to the exoticism and the singular beauty of its flowers. However, techniques which help to keep the floral quality are needed, since the commercial success is tied to the flowers longevity after cut. Thus, the aim of this study was to evaluate preservative solutions on postharvest longevity of Oncidium baueri floral stems. Floral stems, with 60 cm of length and 90% of open flowers were submitted to pretreatment in a pulsing solution, sucrose-based, for 12 and 24 hours, and placed in maintenance solutions containing sucrose and/or Flower®; keeping the control treatment, with distilled water only. These solutions were added with 0.5% of sodium hypochlorite. The evaluation to verify the quality of the flowers was performed daily using a criterion of notes, ranging from 4 to 0. From third day of evaluation, the floral stems submitted to pretreatment with pulsing solution presented statistically lower averages and at the fourth day of evaluation were considered inadequate for marketing. Increased longevity and quality of the flowers can be obtained by keeping the floral stems in distilled water or in maintenance solutions, which are 1% sucrose-based.

Quality maintenance Tropical Plants

The climatic characteristics of the country favor the cultivation of tropical flowers. The continued expansion of this market is due the beauty, exoticit nature and postharvest longevity of flower. However, little is known about the postharvest of tropical plants. Therefore, this paper provides information on harvest, handling and storage of cut tropical plantspostharvest, storage temperature, conditioning solution.

Radiação uv-c na longevidade pós-colheita de tangerinas sob refrigeração

IIncreased shelf life is important for increasing the marketing of mandarin fruits (Citrus reticulata Blanco) and thus raise more distant markets. In this line, the present study was to evaluate the best time of exposure to UV-C radiation in postharvest longevity of fruit. We evaluated the exposure times for 5, 10, 15 and 20 minutes, while fruits that were not exposed configuring the control. The fruits were stored under refrigeration at a temperature of 15 oC and evaluated for 25 days. Every five days were evaluated the fresh weight loss, firmness, soluble solids, titratable acidity, pH, ascorbic acid, maturation rate and respiratory rate. With the exception of pH, other results showed statistical variation in all traits. Exposure times for 15 and 20 minutes showed similar results in all storage times and showed the best average on the post-harvest fruit quality. The UV-C radiation has proved to be a promising technical tool for increasing the life of tangerines, combined with cooling.

Radiação UV-C na Longevidade Pós-Colheita de Tangerinas sob Refrigeração

I Increased shelf life is important for increasing the marketing of mandarin fruits ( Citrus reticulata Blanco) and thus raise more distant markets. In this line, the present study was to evaluate the best time of exposure to UV-C radiation in postharvest longevity of fruit. We evaluated the exposure times for 5, 10, 15 and 20 minutes, while fruits that were not exposed configuring the control. The fruits were stored under refrigeration at a temperature of 15 oC and evaluated for 25 days. Every five days were evaluated the fresh weight loss, firmness, soluble solids, titratable acidity, pH, ascorbic acid, maturation rate and respiratory rate. With the exception of pH, other results showed statistical variation in all traits. Exposure times for 15 and 20 minutes showed similar results in all storage times and showed the best average on the post-harvest fruit quality. The UV-C radiation has proved to be a promising technical tool for increasing the life of tangerines, combined with cooling.

Heliconia ‘Golden Torch’ postharvest: stem ends cutting and renewing vase water benefits

The postharvest longevity is one of the main aspects that should be considered in the production of cut flowers and is a pre-requisite for product quality and marketing success. However, cut flowers are highly perishable products that need to be treated and stored to maintain its quality and value. This study aimed to assess Heliconia psittacorum ‘Golden Torch’ inflorescences postharvest longevity, submitted to periodic stem ends cutting and vase water renewal. The experimental design was a completely randomized 3x2 factorial, corresponding to the stem ends cuts (1 cm; without cutting; cutting at 24 hours; cutting at 48 hours) and water renewal (with and without renewal), with four repetitions. The assessed variables were: water uptake by flower stems (WUFS); loss of fresh stem mass (LFSM); dry matter of flower stems (DMFS) and postharvest longevity (PHL). The stem cut significantly influenced WUFS and LFSM. However, the water renewal factors affected all variables, while the interaction between factors (stem cuts x water renewal) only influenced PHL. The cuts at the stem base of Heliconia ‘Golden Torch’ procedures enable the restoration of water potential and this practice, associated with water renewal during storage allows greater tissues hydration, maintaining the postharvest quality.

Post-harvest longevity of ornamental grasses conditioned in gibberellic acid and 8-hydroxyquinoline sulphate

Abstract Florists’ greens are becoming increasingly important in contemporary floristry. Numerous studies conducted on cut flowers have led to the development of technologies for their post-harvest handling; however, in the case of florists’ greens they are still insufficient. Moreover, the extensive range of florists’ greens lacks leaves and the leafy culms of grasses. The aim of this study was to determine the post-harvest longevity of the leaves and leafy culms of ornamental grasses conditioned in water solutions of gibberellic acid and 8-hydroxyquinoline sulphate. The post-harvest longevity of leaves was examined in cultivars of the following species: Glyceria maxima Hartm. ‘Variegata’, Miscanthus sinensis Thunb. ‘Zebrinus’ and Spartina pectinata Link. ‘Aureomarginata’. The post-harvest longevity of leafy culms was investigated in Alopecurus pratensis L. ‘Aureovariegatus’, Chasmanthium latifolium Michx., Miscanthus sinensis Thunb. ‘Silberspinne’, Pennisetum alopecuroides L. and Phalaris arundinacea L. ‘Picta’. Conditioning in gibberellic acid had a positive effect on the post-harvest longevity and fresh weight loss and the index of leaf greenness of leaves in the case of Miscanthus sinensis ‘Zebrinus’, while conditioning in 8-hydroxyquinoline sulphate improved fresh weight loss and the index of leaf greenness of the leafy culms of Miscanthus sinensis ‘Zebrinus’, Pennisetum alopecuroides and the leaves of Glyceria maxima ‘Variegata’.

Antitranspirant compounds alleviate the mild-desiccation-induced reduction of vase life in cut roses

The vase life sensitivity to mild desiccation (12% weight loss) was addressed in rose, together with alleviation possibilities. The postharvest longevity upon arrival or following mild desiccation was determined on eight cultivars, combined with several morpho-physiological traits. Mild desiccation significantly decreased (10–39%) the vase life of six cultivars (termed sensitive), whereas it did not affect the vase life of two (thus tolerant). More severe desiccation (>12% weight loss) shortened the vase life of a tolerant cultivar. Stomatal control of water loss explained a large part of vase life variation following mild desiccation, whereas cut flower ability to rehydrate or pedicel rigidity (strength, wood density) did not significantly contribute to this variation. Four potentially-mitigating treatments were further tested on the three most sensitive to mild-desiccation cultivars. Antitranspirant treatments [SNP (elicitor of NO) or acetylsalicylic acid in vase water or darkening] decreased the cut flower water loss during the postharvest phase and alleviated the mild-desiccation-induced reduction in vase life. In contrast, Tween 20 (wetting agent) in the vase water shortened vase life. It is concluded that the vase life of previously desiccated cut roses can be extended by employing treatments that reduce the postharvest water loss.

The ERF transcription factor EPI1 is a negative regulator of dark-induced and jasmonate-stimulated senescence in Arabidopsis.

Identification of the factors involved in the regulation of senescence and the analysis of their function are important for both a biological understanding of the senescence mechanism and the improvement of agricultural productivity. In this study, we identified an ERF gene termed "ERF gene conferring Postharvest longevity Improvement 1" (EPI1) as a possible regulator of senescence in Arabidopsis. We found that EPI1 possesses transcriptional repression activity and that the transgenic plants overexpressing EPI1 and expressing its chimeric repressor, EPI1-SRDX, commonly suppressed the darkness-induced senescence in their excised aerial parts. These transgenic plants additionally maintained a high level of chlorophyll, even after the methyl jasmonate (MeJA) treatment, which stimulated senescence in the dark. In addition, we found that senescence-induced and -reduced genes are down- and upregulated, respectively, in the MeJA-treated transgenic plants under darkness. Our results suggest that EPI1 functions as a negative regulator of the dark-induced and JA-stimulated senescence.

Post-harvest longevity of ×Heucherella L. leaves after the application of benzyladenine sprayed on maternal plants

Analyses were conducted on leaves of two &lt;em&gt;×Heucherella&lt;/em&gt; L. cultivars: ‘Solar Power’ and ‘Kimono’. Leaves were harvested at two dates: spring (2014-05-22) and summer (2014-07-26). Prior to each leaf harvest day, the maternal plants were sprayed with benzyladenine (BA) at a concentration of 100, 300 and 600 mg dm&lt;sup&gt;−3&lt;/sup&gt;. After being cut, the leaves were placed in containers with distilled water. In the cultivar ‘Solar Power’, BA at a concentration of 100–600 mg dm&lt;sup&gt;−3&lt;/sup&gt; had an advantageous effect on post-harvest longevity of leaves harvested in summer, improving it by 31.7–98.3%, while in the cultivar ‘Kimono’ BA at the above-mentioned concentrations improved post-harvest longevity of leaves harvested both in spring and summer by almost 2 months. BA at a concentration of 100–600 mg dm&lt;sup&gt;−3&lt;/sup&gt; inhibited proteolysis in leaves of the tested ×&lt;em&gt;Heucherella&lt;/em&gt; cultivars, except for leaves of the cultivars ‘Solar Power’ and ‘Kimono’ harvested in summer from plants sprayed with BA at a concentration of 100 mg dm&lt;sup&gt;−3&lt;/sup&gt;. In these leaves, the protein level was comparable to that in the control leaves. In leaves treated with BA at a concentration of 100–600 mg dm&lt;sup&gt;−3&lt;/sup&gt;, the content of saccharides was higher than in the control plants harvested in the spring and summer.

Conservação pós-colheita de tomate cereja revestidos com película de fécula de mandioca

RESUMO: O tomate após a colheita apresenta-se como um fruto altamente perecível. Por ser um fruto climatérico, seu amadurecimento acarreta uma série de transformações em suas características físicas e químicas. Diante disso, o objetivo do trabalho foi avaliar a longevidade e qualidade pós-colheita de tomate cereja após a aplicação de película de fécula de mandioca sob condições ambiente e controlada. Foram utilizados frutos de duas cultivares, Perinha Água Branca e Mascot, colhidos na maturação fisiológica. Os tratamentos utilizados foram 0%, 1%, 3% e 5% de fécula de mandioca seguidos de avaliações aos 0, 4, 8, 12, 16, 20 e 24 dias de armazenamento, em dois ensaios distintos: um sob temperatura ambiente (25±2°C) e outro sob condições controladas (12°C e UR 90%). O delineamento experimental adotado foi inteiramente casualizado em esquema fatorial 2x4x7 com três repetições de 8 frutos por embalagem. As avaliações realizadas foram perda de massa fresca, acidez titulável, sólidos solúveis, atividade de pectinametilesterase (PME) e relação sólidos solúveis com acidez titulável. Em temperatura ambiente, a perda de massa fresca em 'Mascot' foi maior em frutos revestidos com féculas 3% e 5%. Estas concentrações proporcionaram menor atividade de PME. Em temperatura controlada a acidez titulável foi menor para revestimento de 3% e 5% em 'Mascot' e 'Perinha'. O revestimento de fécula 5% proporcionou baixa longevidade pós-colheita e fécula 1% se assemelhou ao controle em ambas as condições avaliadas. O revestimento de frutos com fécula 3% preservou parâmetros de qualidade como menor acidez e menor atividade de PME sendo considerado o mais eficaz.

Ethylene and 1-methylcyclopropene action over senescence of nasturtium flowers

ABSTRACT: This work describes ethylene and 1-methylcyclopropene (1-MCP) action on post-harvest shelf life of four development stages of nasturtium flowers. To reach this goal, we carried out three experiments. In the first and second experiments, we studied five ethylene (0; 0.1; 1; 10; 100 and 1000 μL/L) and three 1-MCP concentrations (0.25; 0.5 and 0.75 μL/L), respectively. In the third experiment, 1-MCP was followed by combined with ethylene (only 1-MCP; only ethylene; and 24 hours of exposure to 0.75 μL/L 1-MCP followed by 24 hours of exposure to 100 μL/L ethylene). All experiments had two control treatments, one keeping non-exposed flowers inside and another outside exposure chambers. Experiments were set in factorial design, in complete blocks at random, with four 10-flower replications each. Flower senescence was determined by a pre-established visual scale and by observing floral bud development. Ethylene dose above 10 μL/L induced flower wilting and premature senescence from the second floral development stage. Furthermore, higher concentrations of exogenous ethylene promoted irregular flower opening and/or morphological abnormalities in opened flowers. 1-MCP effectively extended post-harvest longevity of nasturtium flowers, independent of the concentration and even in the presence of exogenous ethylene.

Flowering stem storage of Heliconia psittacorumL. f. cv. Trópica

Heliconia psittacorum L. f. is a tropical flower species with high economic potential due to its diversity of shapes, colours and its long vase life. However, storage conditions (temperature and relative humidity; RH) for flower stems during transport is a particular issue to each cultivar determining duration of vase life. Flowering stems were obtained from a commercial plantation in Campo Grande, Iztaczoquitlán, Veracruz, Mexico. The variables evaluated over a 10 day storage period were: fresh weight, colour using the CIE model (L*, a*, b*), peroxidase activity (POX), respiratory intensity and ethylene. The temperature was in the range of 12–26°C, RH between 37 and 90% and light between 0 and 150μmolm−2s−1. A repeated measures experimental design for non-destructive variables was used and a completely randomized design for destructive variables. The conditions which best preserved the quality characteristics during the stem storage (α=0.05) were: 15°C, 63% RH and 0μmolm−2s−1; 16°C, 60% RH and 150μmolm−2s−1 and 12°C, 90% RH and 26μmolm−2s−1. The average vase life (VL) was 6.6 days with 15°C, 63% RH and 0μmolm−2s−1 and total postharvest longevity (TPL) was 16.6 days. In contrast the control treatment had a VL of 2.5 days and a TPL of 12.5 days (24±2°C, 60±5% RH and 10μmolm−2s−1). The presence of leaves increased the respiration, but there was no significant release of ethylene, hence, storage treatments did not affect the ethylene production.

Xylem plugging and postharvest longevity of cutAcacia holosericea

An inherently short vase life is a problematic characteristic of cut flowers and foliage for otherwise attractive native Australian Acacia spp. Reasons underlying the poor postharvest water uptake of cut acacia stems have been elusive. A. holosericea was used to investigate possible bacteria-induced and wound-induced xylem occlusion. The effects of bacterial-and wound-induced xylem blockage on water uptake were investigated by light and scanning and transmission electron microscopy. Observations were made on cut stems that stood into either deionised water (DIW; control) or 0.5 mM Cu2+ solution and on stems pulsed with 2.2 mM Cu2+ solution and then stood into DIW. The stem-end region of cut A. holosericea that stood into DIW or Cu2+ solution became covered with bacterial growth after 3 days. Regardless of the bacterial biofilm, the Cu2+ treated stems had improved water relations and vase life. Therefore, the biofilm had little or no effect on cut A. holosericea longevity. Further observations revealed presence of a vessel-occluding substance (gel) originating from axial parenchyma cells in direct physical contact with xylem vessels. The gel exuded into vessel lumens through pit membranes, evidently as a wound-response. Xylem occlusion by gels in A. holosericea may be especially problematic due to an abundance of secretory contact cells relative to xylem elements. Nonetheless, active wound response processes may be the key determinant of short postharvest longevity for this and possibly other cut Acacia spp. Cu2+ treatments, however, disrupted the secretory function of axial parenchyma cells thereby preventing vessel occlusion by the gels.