Storage temperature affects the rate and extent of wound-healing in a number of root and tuber crops. The effect of storage temperature on wound-healing in sugarbeet (Beta vulgaris L.) roots, however, is largely unknown. Wound-healing of sugarbeet roots was investigated using surface-abraded roots stored at 6 and 12°C for 28 days. Surface abrasions are common injuries of stored roots, and the storage temperatures used are typical of freshly harvested or rapidly cooled roots. Transpiration rate from the wounded surface and root weight loss were used to quantify wound healing. At 12°C, transpiration rate from the wounded surface declined within 14 days and wounded roots lost weight at a rate similar to unwounded controls. At 6°C, transpiration rate from the wounded surface did not decline in the 28 days after injury, and wounded roots lost 44% more weight than controls after 28 days storage. Melanin formation, lignification, and suberization occurred more rapidly at 12°C than at 6°C, and a continuous layer of lignified and suberized cells developed at 12°C, but not at 6°C. Examination of enzyme activities involved in melanin, lignin, and suberin formation indicated that differences in melanin formation at 6 and 12°C were related to differences in polyphenol oxidase activity, although no relationships between suberin or lignin formation and phenylalanine ammonia lyase or peroxidase activity were evident. Wound-induced respiration was initially greater at 12°C than at 6°C. However, with continued storage, respiration rate of wounded roots declined more rapidly at 12°C, and over 28 days, the increase in respiration due to injury was 52% greater in roots stored at 6°C than in roots stored at 12°C. The data indicate that storage at 6°C severely slowed and impaired wound-healing of surface-abraded sugarbeet roots relative to roots stored at 12°C and suggest that postharvest losses may be accelerated if freshly harvested roots are cooled too quickly.

Species from Capsicum genus are used for different purposes and in more recent years as ornamental potted plant. Despite the increased commercial importance, there are only a few studies on the environmental factors affecting the post-production shelf life of these ornamental plants. The presence of ethylene induces various responses on potted peppers, reducing the shelf life of sensitive cultivars. This study aimed to evaluate the effects of ethylene and the inhibitors of ethylene action, 1-methylcyclopropene (1-MCP) and silver thiosulfate (STS) on the shelf life of potted 'Calypso' and 'MG 302' peppers. Cultivar 'MG 302' showed intermediate sensitivity to ethylene action, while the cultivar 'Calypso' showed complete abscission of leaves when exposed to ethylene. In both cultivars, treatment with STS + Ethylene presented symptoms of phytotoxicity in plants, while treatment with 1-MCP + Ethylene was effective in delaying senescence and abscission for the cultivar 'MG 302', while cultivar 'Calypso' showed abscission similar to control plants. Plants treated with STS showed the longest durability when compared to the other treatments, about six days for 'Calypso' and 18 days for 'MG 302'. Nevertheless, plants treated with 1-MCP also exhibited good shelf life, about six days for 'Calypso' and nine days for the 'MG 302'. Although the treatment with STS was more efficient on the plants shelf life, did not completely block the action of ethylene and exhibited some phytotoxicity, while the treatment with 1-MCP had good efficiency without inducing any toxicity.

Within the genetic variability of the Capsicum genus there are plants with ornamental potential, but awry height required by the market. Paclobutrazol (PBZ), gibberellin retardant and growth inhibitor, is normally used as alternative to reduce plant height. The objective was to evaluate the PBZ (0, 25, 50 and 75 mg L-1) effect on plant height of eight pepper genotypes. Seven accessions [BGH 1032, BGH 1039, BGH 7073 (C. annuum), BGH 4285, BGH 4199, BGH 4355 and BGH 6371 (C. chinense)] of the germplasm bank from Universidade Federal de Viçosa and one access [MG 302 (C. annuum)] from the germplasm bank of the Empresa de Pesquisa Agropecuária de Minas Gerais were evaluated. The PBZ application was ineffective in altering plant architecture of BGH 6371. PBZ at 25 mg L-1 resulted in plants with better ornamental characteristics of the accesses BGH 1032 and BGH 1039. Considering the cost-benefit, the indicated dose for BGH 4285, BGH 7073 and MG 302 access is 25 mg L-1 PBZ. The PBZ application in BGH 4199 and BGH 4355 accesses, despite reducing plant height, did not improve the ornamental characteristics, resulting in plants without canopy pattern.

The objective of this work was to evaluate the action of paclobutrazol (PBZ) on the growth and ornamental value of two pepper accessions and two commercial cultivars of ornamental pepper - Biquinho Vermelha and Bode Amarela. A PBZ aqueous solution (250 mL) was used to soak the substrate at 0, 20, 40, and 60 mg L-1 a.i. concentrations when the plants had 12 cm height. At the end of plant growth, the follwoing parameters were evaluated: plant height, chlorophyll content in leaves, number of fruit and leaves, and canopy compactness at the time the plants reached maturity to be marketed, with 30% of ripe fruit. Irrespective of the applied PBZ concentration, plant height diminished, and chlorophyll content increased. PBZ did not improve the ornamental characteristics of the genotypes 'Biquinho Vermelha' and 2334PB, which resulted in unsuitable plants for market requirements. For the genotypes 2345PB and 'Bode Amarela', the application of 20 mg L-1 of PBZ is the most indicated, and it results in plants with adequate ornamental characteristics required by the national market of flowers and ornamental plants.

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