Postharvest Fruit Decay Research Articles

Responses of yeast biocontrol agents to environmental stress.

Biological control of postharvest diseases, utilizing wild species and strains of antagonistic yeast species, is a research topic that has received considerable attention in the literature over the past 30 years. In principle, it represents a promising alternative to chemical fungicides for the management of postharvest decay of fruits, vegetables, and grains. A yeast-based biocontrol system is composed of a tritrophic interaction between a host (commodity), a pathogen, and a yeast species, all of which are affected by environmental factors such as temperature, pH, and UV light as well as osmotic and oxidative stresses. Additionally, during the production process, biocontrol agents encounter various severe abiotic stresses that also impact their viability. Therefore, understanding the ecological fitness of the potential yeast biocontrol agents and developing strategies to enhance their stress tolerance are essential to their efficacy and commercial application. The current review provides an overview of the responses of antagonistic yeast species to various environmental stresses, the methods that can be used to improve stress tolerance and efficacy, and the related mechanisms associated with improved stress tolerance.

Enhanced control of postharvest citrus fruit decay by means of the combined use of compatible biocontrol agents

Fourteen Pseudomonas spp. and three Trichoderma spp. strains were tested in vitro for their antagonistic properties against Penicillium digitatum, the causal agent of citrus green mold. Bacterial and fungal strains strongly inhibited the pathogen growth in vitro on PDA and on a citrus-based medium. Inhibitory effects were increased when Pseudomonas and Trichoderma strains were applied in combination. Inhibitory effects were also increased by mixtures of Pseudomonas cells and Trichoderma atroviride P1 culture filtrates. On the opposite, bacterial and fungal filtrates in mixture never induced an improved efficacy, thus indicating that the presence of living bacterial cells was required for a synergistic effect. Accordingly, incidence and severity of disease on orange cv. Tarocco and lemon cv. Femminello were consistently reduced when Pseudomonas and Trichoderma strains were applied 72h before challenging P. digitatum. Pseudomonas syringae strains were the most effective and several combinations had a biocontrol activity higher than one of the each antagonistic microorganism applied alone. The treatments comprising six P. syringae in mixture with Trichoderma strains T22, P1 and T34 were the most effective, with 80–100% control of green mold. The development of green mold decay was also effectively inhibited in small-scale dip-treatments, either by single applications or by their mixtures. These experiments suggest that the combination of Pseudomonas spp. and Trichoderma spp. strains could be considered as a promising mean for the control of citrus green mold decay, supporting the concept that an improved disease control is given by the combined action of the two agents.

High incidence of preharvest colonization of huanglongbing-symptomatic citrus sinensis fruit by Lasiodiplodia theobromae (Diplodia natalensis) and exacerbation of postharvest fruit decay by that fungus.

Huanglongbing (HLB), presumably caused by the bacterium "Candidatus Liberibacter asiaticus," is a devastating citrus disease associated with excessive preharvest fruit drop. Lasiodiplodia theobromae (diplodia) is the causal organism of citrus stem end rot (SER). The pathogen infects citrus fruit under the calyx abscission zone (AZ-C) and is associated with cell wall hydrolytic enzymes similar to plant enzymes involved in abscission. By means of DNA sequencing, diplodia was found in "Ca. Liberibacter asiaticus"-positive juice from HLB-symptomatic fruit (S) but not in "Ca. Liberibacter asiaticus"-negative juice. Therefore, the incidence of diplodia in fruit tissues, the impact on HLB-related postharvest decay, and the implications for HLB-related preharvest fruit drop were investigated in Hamlin and Valencia oranges. Quantitative PCR results (qPCR) revealed a significantly (P < 0.001) greater incidence of diplodia in the AZ-C of HLB-symptomatic (S; "Ca. Liberibacter asiaticus" threshold cycle [CT] of <30) than in the AZ-C of in asymptomatic (AS; "Ca. Liberibacter asiaticus" CT of ≥30) fruit. In agreement with the qPCR results, 2 weeks after exposure to ethylene, the incidences of SER in S fruit were 66.7% (Hamlin) and 58.7% (Valencia), whereas for AS fruit the decay rates were 6.7% (Hamlin) and 5.3% (Valencia). Diplodia colonization of S fruit AZ-C was observed by scanning electron microscopy and confirmed by PCR test and morphology of conidia in isolates from the AZ-C after surface sterilization. Diplodia CT values were negatively correlated with ethylene production (R = -0.838 for Hamlin; R = -0.858 for Valencia) in S fruit, and positively correlated with fruit detachment force (R = 0.855 for Hamlin; R = 0.850 for Valencia), suggesting that diplodia colonization in AZ-C may exacerbate HLB-associated preharvest fruit drop.

Characterization of three linalool synthase genes from Citrus unshiu Marc. and analysis of linalool-mediated resistance against Xanthomonas citri subsp. citri and Penicilium italicum in citrus leaves and fruits

Three cDNA clones from Satsuma mandarin (Citrus unshiu Marc.) were isolated and expressed in Escherichia coli. CuSTS3-1 and CuSTS3-2 encode linalool synthases and CuSTS4 encodes a nerolidol/linalool synthase. Transcripts of CuSTS3-1, CuSTS3-2 and CuSTS4 were abundant in young fruit at 60 days after flowering (DAF), flowers and leaves, respectively. Treatments with Xanthomonas citri subsp. citri (XCC), the causal agent of citrus canker and Penicillium italicum (PI), the cause of post-harvest fruit decay, and wounding up-regulated CuSTS3-1 in fruit and mainly CuSTS4 in leaves. Linalool, citral, geraniol and citronellol showed strong antibacterial and antifungal activities against XCC and PI in vitro, while most other mono-and sesquiterpenes, including limonene and gamma-terpinene, did not. Linalool, used at levels similar to those present in resistant Ponkan mandarin (Citrus reticulata Blanco) leaves, was able to inhibit growth of XCC in vitro. Compared to other five citrus types, linalool accumulated at extraordinarily high levels in Ponkan mandarin leaves and was released at high amounts from their leaves, while it was hardly detectable in the most susceptible species, indicating that linalool biosynthesis and accumulation might be involved in plant defense against bacterial and fungal pathogens and be associated with field resistance to citrus canker.

An antifungal role of hydrogen sulfide on the postharvest pathogens Aspergillus niger and Penicillium italicum.

In this research, the antifungal role of hydrogen sulfide (H2S) on the postharvest pathogens Aspergillus niger and Penicillium italicum growing on fruits and under culture conditions on defined media was investigated. Our results show that H2S, released by sodium hydrosulfide (NaHS) effectively reduced the postharvest decay of fruits induced by A. niger and P. italicum. Furthermore, H2S inhibited spore germination, germ tube elongation, mycelial growth, and produced abnormal mycelial contractions when the fungi were grown on defined media in Petri plates. Further studies showed that H2S could cause an increase in intracellular reactive oxygen species (ROS) in A. niger. In accordance with this observation we show that enzyme activities and the expression of superoxide dismutase (SOD) and catalase (CAT) genes in A. niger treated with H2S were lower than those in control. Moreover, H2S also significantly inhibited the growth of Saccharomyces cerevisiae, Rhizopus oryzae, the human pathogen Candida albicans, and several food-borne bacteria. We also found that short time exposure of H2S showed a microbicidal role rather than just inhibiting the growth of microbes. Taken together, this study suggests the potential value of H2S in reducing postharvest loss and food spoilage caused by microbe propagation.

Effect of Pichia membranaefaciens on ROS metabolism and postharvest disease control in citrus fruit

The yeast Pichia membranaefaciens has antagonistic effects against a wide range of phytopathogenic fungi that cause postharvest fruit decay. This work evaluated the effects of P. membranaefaciens on the reactive oxygen species (ROS) metabolism and disease control in harvested citrus fruit (Citrus sinensis L. Osbeck). The lesion diameter caused by Penicillium italicum and Penicillium digitatum on citrus fruit was remarkably reduced when the fruit was point-inoculated or dipped in a suspension of P. membranaefaciens at 1 × 108 CFU mL−1. The application of P. membranaefaciens on citrus fruit enhanced the activity of superoxide dismutase, ascorbate peroxidase, and glutathione reductase, as well as the levels of hydrogen peroxide, the superoxide anion and glutathione, but inhibited the decreasing ascorbic acid content. Furthermore, catalase activity was decreased by the same treatment. These results indicated that yeast treatment induced the synthesis of antioxidant enzymes which might have antagonistic effects against postharvest green and blue mold infection in citrus fruit.

Evaluating Strawberry Breeding Selections for Field and Postharvest Fruit Decay

Fruit from the annual replicated yield assessments for the USDA-ARS strawberry (Fragaria x ananassa Duchesne ex Rozier) breeding program at Beltsville, MD in 2010 were evaluated for postharvest decay development after storage at 5°C. A statistically significant correlation between percentage decay of fruit in the field and percentage decay of fruit from post-harvest evaluation was observed when data were analyzed on a genotypic mean basis (r = 0.37) or a field plot basis (r = 0.25) across all harvests. Analysis of the same data on a plot by harvest combination basis resulted in a statistically significant correlation for only one harvest date. While significant, the level of correlation on a genotypic mean basis is not strong enough to dismiss the need for post-harvest evaluation. The percentage postharvest decay increased over harvests, while the percentage decay at harvest, in the field, did not. Weather data from 2010 indicated that field conditions just a few days before harvest can affect percentage decay at harvest differently than percentage decay in postharvest storage; rain events were correlated with increased percentage decay in the field but not postharvest decay, while dry air was correlated with decreased percentage decay postharvest but not decay in the field. These findings suggest that, in some environments, conditions after flowering can have a more significant role in the fruit decay than previously has been reported.

Fungal Decay and Shelf Life of Oranges Coated With Chitosan and Bergamot, Thyme, and Tea Tree Essential Oils

Chitosan coatings, containing or not essential oils (bergamot, thyme and tea tree oil), were applied to oranges (cv. Navel Powell). Antifungal effect was evaluated by applying coatings before and after inoculating the fruit with Penicillium italicum CECT 2294 (10(5) spores/mL), preventive and curative treatments, respectively. The effect of coatings on the quality parameters (acidity, pH, soluble solids, juice percentage, weight loss, firmness, color parameters, and respiration rate) was controlled for the different oranges samples throughout the cold storage time. Preventive antimicrobial treatments with coatings containing tea tree oil were the most effective with a reduction of the microbial growth (expressed as the percentage of infected samples) of 50%, as compared to the uncoated samples. The coatings did not lead to any relevant changes in the development of the sample quality parameters throughout the cold storage, except for a slightly reduced loss of both weight and firmness when the coatings contained bergamot oil. Results of this study are a useful tool for the development of new environmental friendly and healthier commercial applications in the control of the main postharvest fungal decay of citrus fruits.

Evaluating strawberry breeding selections for postharvest fruit decay

Fruit from the annual replicated yield assessments for the USDA-ARS strawberry (Fragaria ×ananassa Duchesne ex Rozier) breeding program at Beltsville, MD, 2007 and 2008, were evaluated for postharvest decay development after storage at 5 °C. Generalized linear genotype × year mixed model analysis of covariance with overdispersed binomial distribution, logit link function, and Laplace optimization method was used to determine the relationships between postharvest proportion decay and storage period (SP), season’s harvest number (HN), and genotype-specific harvest number through the season; conditioned on the confounding of harvest with SP. To determine if limiting analyses to replicates (plot × harvest combinations) with a minimum number of berries would increase statistical precision, concurrent analyses were conducted using data from replicates with more than: zero, three, and six berries. Limiting data to genotypes for which more than three or more than six berries could be evaluated, resulted in loss of data and reduced statistical power. Within the range of SP observed, 13–19 days, consistency among genotypes of the linear relationship between SP and logit postharvest proportion decay, unless strongly influenced by a confounded harvest effect, indicated all SP in the range tested provided equivalent ability to discern genotypes. The significant genotype × HN interaction effect indicated maximizing the number of harvests was preferable to limiting to a few “informative” harvests. The significant genotype × year interaction effect indicated the decision to release a genotype as a cultivar will demand multiple years of evaluation. Making determinations each year to discard genotypes or use them as parents for postharvest quality was best facilitated by the simple process of calculating arithmetic genotypic means for each harvest date separately, charting the results, and using the charts to visually assess genotypic performance trends across harvests.

In vitro control of post-harvest fruit rot fungi by some plant essential oil components.

Eight substances that are main components of the essential oils from three Mediterranean aromatic plants (Verbena officinalis, Thymus vulgaris and Origanum vulgare), previously found active against some phytopathogenic Fungi and Stramenopila, have been tested in vitro against five etiological agents of post-harvest fruit decay, Botrytis cinerea, Penicillium italicum, P. expansum, Phytophthora citrophthora and Rhizopus stolonifer. The tested compounds were β-fellandrene, β-pinene, camphene, carvacrol, citral, o-cymene, γ-terpinene and thymol. Citral exhibited a fungicidal action against P. citrophthora; carvacrol and thymol showed a fungistatic activity against P. citrophthora and R. stolonifer. Citral and carvacrol at 250 ppm, and thymol at 150 and 250 ppm stopped the growth of B. cinerea. Moreover, thymol showed fungistatic and fungicidal action against P. italicum. Finally, the mycelium growth of P. expansum was inhibited in the presence of 250 ppm of thymol and carvacrol. These results represent an important step toward the goal to use some essential oils or their components as natural preservatives for fruits and foodstuffs, due to their safety for consumer healthy and positive effect on shelf life extension of agricultural fresh products.

Biological control of postharvest diseases of fruit

Postharvest decay in harvested fruit causes considerable economical losses. Fungicides are the primary means to control these losses. Public concern in food safety and environmental issues and the increase of pathogen resistant populations have enhanced the interest in developing alternative methods to fungicides to control postharvest fruit decay. During the last two decades a huge information and advances concerning the selection of antagonists, mode of action, different approaches to enhance biocontrol activity, formulation and production have been achieved, and some biofungicides are already in the market. It is likely that several more products will enter the market in the near future, as the result of the biological control research programs worldwide. Nonetheless, it is necessary to continue finding new potential microorganisms, better understanding the mode of action, and pathogen, antagonist and host interactions, to increase the potential of biocontrol helping to become a real alternative to synthetic postharvest fungicides. This article presents an overview of postharvest biological control approaches and explores new research possibilities to improve biocontrol activity.

Mutations of β-tubulin codon 198 or 200 indicate thiabendazole resistance among isolates of Penicillium digitatum collected from citrus in Taiwan

Penicillium digitatum causes green mold on citrus, resulting in severe postharvest fruit decay and economic losses in many citrus-producing areas of the world. Forty isolates of P. digitatum were cultured from citrus groves, packinghouses, and local markets in Taiwan, and assessed quantitatively for their sensitivity to thiabendazole (TBZ) fungicide. Sensitivity assays using a 96-well microtiter plate revealed that, of 40 isolates examined, only one isolate collected from fruit produced in Taiwan and two isolates from Florida-imported citrus fruit were sensitive to TBZ. The concentration of TBZ causing a 50% growth reduction (EC(50)) was less than 1 μg/mL. The remaining 37 isolates could tolerate high concentrations of TBZ, with an EC(50) greater than 80 μg/mL. Overall, more than 97% of P. digitatum isolates tested in Taiwan were found to be resistant to TBZ. In vitro assays also revealed the ineffectiveness of TBZ for controlling a TBZ-resistant isolate on sweet oranges. A sequence analysis of β-tubulin genes revealed that all TBZ-resistant isolates displayed a single transversion point mutation, resulting in a change at either amino acid 198 (glutamic acid→glutamine) or 200 (phenylalanine→tyrosine). The repetitive use of a single fungicide over several decades has favored the selection and dominance of TBZ-resistant isolates of P. digitatum.

1-METHYLCYCLOPROPENE DELAYS POSTHARVEST RIPENING AND REDUCES DECAY IN HAMI MELON

The effects of 1-methylcyclopropene (1-MCP) on postharvest ripening and fruit decay in Hami melon were investigated. Melons were treated with 0, 0.1, 1, or 5 µL/L 1-MCP at 25C for 24 h and then stored at 25C for 16 days. 1-MCP treatment significantly inhibited respiration rate and ethylene production and delayed their climacteric rise. The treatment also significantly inhibited the decrease of firmness and the increase of electrolyte leakage. Moreover, treatment with 1 or 5 µL/L 1-MCP maintained significantly higher total soluble solids, vitamin C and chlorophyll contents. In addition, 1-MCP treatment significantly delayed the incidence of fruit decay and inhibited the increase of decay index. The efficacy of 1-MCP on delaying postharvest ripening and controlling fruit decay increased with increasing concentration. These results indicate 1-MCP treatment has great potential to extend shelf-life and maintain quality in Hami melon during distribution at ambient temperature. PRACTICAL APPLICATIONS 1-Methylcyclopropene (1-MCP) has been commercially used to delay postharvest ripening and extend the storage life on some climacteric fruits. Hami melon has a very short shelf-life mainly due to fruit ripening and decay, which causes significant economic losses. In this study, a postharvest application of 1-MCP significantly delayed ripening and reduced fruit decay while maintaining overall quality during storage at 25C. The results will allow long-distance transportation and marketing of Hami melon and benefit growers, shippers and distributors of this melon fruit.

Effects of chitin and its derivative chitosan on postharvest decay of fruits: a review.

Considerable economic losses to harvested fruits are caused by postharvest fungal decay during transportation and storage, which can be significantly controlled by synthetic fungicides. However, considering public concern over pesticide residues in food and the environment, there is a need for safer alternatives for the control of postharvest decay to substitute synthetic fungicides. As the second most abundant biopolymer renewable source in nature, chitin and its derivative chitosan are widely used in controlling postharvest decay of fruits. This review aims to introduce the effect of chitin and chitosan on postharvest decay in fruits and the possible modes of action involved. We found most of the actions discussed in these researches rest on physiological mechanisms. All of the mechanisms are summarized to lay the groundwork for further studies which should focus on the molecular mechanisms of chitin and chitosan in controlling postharvest decay of fruits.

Influence of Summer Savory Essential Oil (Satureja hortensis) on Decay of Strawberry and Grape

The essential oil isolated from the aerial parts of wild Turkish Satureja hortensis L. (summer savory) was analyzed by GC-MS, and carvacrol (54.7 %), y-terpinene (20.9 %), p-cymene (12.3 %), a-terpinene (2.0 %), and thymol (2.0 %) were found to be major components of the oil. Post-harvest decay of fruits caused by some fungi is still a most important problem and causes major crop losses during storage and shipment. High relative humidity during storage and marketing conditions accelerate development of fungal disease and decay of the grapes. The six different concentrations of the oil (0.01, 0.02, 0.04, 0.11, 0.22 and 0.45 µL/cm3) were tested for their effectiveness in reducing decay of strawberry and grape fruits at three storage temperature (5, 10 and 20°C). The oil tested reduced decay of strawberry and grape fruits compared to controls, in particularly at low temperatures (5 and 10°C). Decay reducing effect of the oil on strawberry and grape fruits increased with increase in doses of the oil. However, microbial development in the fruits increased with increase in temperature. Nevertheless, the present results showed that S. hortensis essential oil has a significant reducing effect on the decay of strawberry and grape fruits during storage at low temperatures. Therefore, the essential oil of summer savory may be a potential source of alternative fungicides to protect strawberry and grape fruits as well as other stored products from pathogens and saprophytes.

CFD MODELLING OF A FUNGICIDE THERMONEBULISATION SYSTEM FOR FRUIT STORAGE ROOMS

Inefficiency in fungicide treatment is one of the reasons for postharvest decay of fruits during the storage period. Postharvest treatment of fungicides using thermonebulisation fogging systems offers a promising means to minimize such postharvest decay. Moreover, this treatment method reduces the use of fungicides in the orchards, minimizes residues on the fruits and improves ecological and environmental sustainability. A three-dimensional computational fluid dynamics (CFD) model was developed to help optimize the application of the fungicide particles inside the fruit storage room. An Eulerian-Lagrangian multiphase flow model was used. The model takes into account two-way coupling with turbulent dispersion of the particles. The particle diameter distribution at the exit of the thermonebuliser was measured and used as an input to the model. The product loaded in vented bins was considered as a porous medium, where the loss coefficients to the three orthogonal directions were approximated using simulation of the flow through the vented boxes and stacks. The dynamic behaviour of the fan was also taken into account. The distribution of the fungicide particles was highly affected by the air flow distribution inside the room. Good agreement was found between measured and predicted results of deposition of fungicide particles.

Yeasts associated with nectarines and their potential for biological control of brown rot

Resident fruit microflora has been the source of biocontrol agents for the control of postharvest decay of fruits and the active ingredient in commercialized biocontrol products. With the exception of grapes and apples, information on the resident microflora of other fruits is only fragmentary, but greater knowledge in this area can be very helpful in developing biocontrol strategies. We characterized the yeast microflora of nectarines ('Croce del Sud') from the early stages of fruit development until harvest. The fruit samples were collected from trees in an unmanaged orchard. The resident fruit microflora was separated from the occasionally deposited microorganisms by discarding initial fruit washings before the final wash, followed by sonication and plating on NYDA medium. The isolated yeasts were identified by BIOLOG and by sequencing the D1/D2 domain of a large subunit of the rRNA gene and, where available, the ITS sequence. BIOLOG identified 19 and the genetic analysis 23 species of yeasts. Although the identification by these two systems was not always the same, the predominant yeasts were Rhodotorula spp., Sporodiobolus spp., Cryptococcus spp., Pichia spp., Candida spp. and yeast-like Aureobasidium pullulans. Several of the taxa appear to represent new species. The preliminary biocontrol tests against brown rot of nectarine fruit caused by Monilinia fructicola indicates significant decay control potential of some of the identified yeast species, namely Cryptococcus magnus, Cryptococcus sp. nov., Sporidiobolus pararoseus, A. pullulans and Rhodotorula sp. nov.

Thiabendazole resistance and mutations in the β-tubulin gene ofPenicillium expansumstrains isolated from apples and pears with blue mold decay

Penicillium expansum is the causal agent of blue mold rot, a postharvest decay of stored fruits. This fungus also produces the mycotoxins patulin and citrinin. Control of P. expansum still relies mainly on the use of fungicides such as thiabendazole. Since its introduction, resistant strains have been reported. The aim of this work was to investigate the thiabendazole resistance and mutations in the beta-tubulin gene of P. expansum strains isolated from apples and pears with blue mold decay from Spain. A total of 71 strains of P. expansum were scored for resistance to thiabendazole and the beta-tubulin gene was sequenced. Out of 71 strains, 37 were sensitive and 34 were resistant to thiabendazole. Regarding the beta-tubulin gene sequence, 10 different genetic types were determined, with a 99.7-100% similarity. When the amino acid sequence was deduced, five different amino acid sequences were found. All except one of the sensitive strains lacked mutations in the region sequenced. Of the 34 resistant strains, only eight had mutations that involved the residues 198 and 240. All the strains with mutations at position 198 always corresponded to resistant isolates. However, a high percentage of resistant strains had no mutations in the region of the beta-tubulin gene sequenced, and so other mechanisms may be involved in thiabendazole resistance.

Effects of microwave treatment on postharvest decay of fruits: a review

Purpose of review: Postharvest decay causes considerable losses to harvested fruits during transportation and storage. Synthetic fungicides are primarily used to control postharvest decay loss. However, the recent trend is shifting toward safer and more eco-friendly alternatives for the control of postharvest decay. Microwave power as a potential alternative to synthetic fungicides is increasingly used in controlling postharvest decay of fruits. This review aims at understanding microwave power fully and laying a good foundation for further research and application of this technology to controlling postharvest decay. Main findings: In this review, we mainly introduce the control effect of microwave power on postharvest decay in different fruits, discuss the possible mode of action in this process and the method of enhancing the control efficacy. These results are important for further use of microwave power on postharvest decay. Directions for future research: Future studies should focus on the mechanisms of action of microwaves in systemic resistance of fruits, finding more effective methods to enhance the control efficacy of microwave power on postharvest decay of fruits, and developing the technology to be used under large-scale operations.

Bell Pepper Plant Growth, Gas Exchange, Mineral Nutrition, Phytophtora Blight, Fruit Yield, and Postharvest Fruit Decay as Affected by Harpin Protein

Harpin protein is an elicitor of hypersensitive response in plants. When applied exogenously, harpin is claimed to control plant diseases, increase plant growth and yield, and reduce postharvest fruit decay. The plant responses to harpin application have been inconsistent. This study was intended to determine the effects of harpin on plant growth, gas exchange, control of Phytophtora blight, fruit yield, and control of postharvest fruit decay in bell pepper (Capsicum annum L.). When applied only before planting, harpin increased marketable yield of bell pepper, but when applied both before and after planting, it reduced marketable and total yields. Harpin had no beneficial effect on plant growth, leaf mineral nutrient content, leaf gas exchange, incidence of Phytophtora blight in the field, and incidence of softrot of fruit after harvest. Harpin had little or no positive effect on most plant attributes in bell pepper in the field or after harvest.