Five members of the Proteaceae and 13 Australian native cut flower cultivars were stored for 35 days under standard conditions at 1C to assess their ability to withstand long-term storage and transport. Protea cynaroides L., Leucadendron `Silvan Red', Leucospermum `Firewheel', Thryptomene calycina (Lindl.) Stapf., Telopea speciosissima R. Br., and Verticordia grandtiflora Endl. retained a vase life of at least 7 days after 21 days of storage. Leucospermum cordifolium Salisb. ex Knight, Protea neriifoli R. Br., Chamelaucium uncinatum `Alba', C. uncinatum `Purple Pride', Verticordia monadelpha Turcz., Verticordia plumosa (Desf.) Druce, and Verticordia nitens (Lindl.) Schau. suffered a decline in vase life ranging from 31% to 100% after 14 to 21 days of storage. Species of Verticordia and Chamelaucium were particularly susceptible to fungal infection. Anigozanthos pulcherrimus Hook. and the Anigozanthos cultivars Ruby Delight, Bush Harmony, Bush Haze, and Gold Fever all showed a significant reduction in vase life after 14 days of storage compared with unstored controls.
Abstract
In a germination test with strawberry seed of different ages stored at 40°F, 23-year-old seed germinated as well as 1-year-old seed. Germination was relatively high for all of the seed lots, despite differences in age.
Abstract
Incorporation of thiabendazole (TBZ) in the wax coating applied to grapefruit significantly reduced the amount of low temp pitting which developed during prolonged storage at 8 and 12°C.
Abstract
An inexpensive method for accurate control and measurement of fresh air introduction into experimental storage rooms is described.
`Columbia' and `Gebhard' strains of red `d'Anjou' pears (Pyrus Communis L.) harvested at similar maturity exhibited different ripening behavior after monthly removal from 1C storage in air. `Columbia' fruit produced ethylene at higher rates than `Gebhard' fruit during 15 days of ripening at 20C after each corresponding storage interval, `Gebhard' fruit required a longer period of chilling than `Columbia' fruit to generate noticeable rates of ethylene during ripening. The unripened fruit of both strains contained similar amounts of ACC at each corresponding storage interval. At each corresponding ripened state, ACC content in `Columbia' fruit increased 2 to 3-fold, while that in `Gebhard' fruit changed very little. After sufficient chilling, `Columbia' fruit were capable of softening to proper ripeness, and they developed buttery and juicy texture as indicated by the apparent reduction of extractable juice (EJ) content. `Gebhard' fruit also softened but to a lesser extent than `Columbia' fruit. Ripened `Gebhard' fruit had only slightly lower levels of EJ than unripened fruit and did not develop a buttery and juicy texture after any storage intervals. Titratable acidity (TA) in fruit of both strains varied between for the 1988 and 1989 seasons but decreased significantly during storage in both years. Soluble solids concentrations (SSC) in both strains also varied seasonally but did not change during storage or ripening. Chemical name used: 1-aminocyclopropane-1-carboxylic acid (ACC).
Abstract
Ripening of ‘Bartlett’ pears at 20°C was assessed in samples harvested weekly beginning 4 weeks prior to commercial harvest maturity. Ripening was promoted by delaying harvest, by 1- and 2-week periods of storage at 4.4°C, or both. Early summer treatments with 750 and 7500 ppm succinic acid-2,2-dimethylhydrazide (SADH) delayed ripening but this effect was counteracted by both delayed harvest and postharvest storage at 4.4°C. It is concluded that SADH delays ripening by influencing an endogenous mechanism for controlling ripening in pears.
Experiments were conducted to determine if ethylene influences chilling injury, as measured by percentage of slices exhibiting water-soaked areas in fresh-cut tomato slices of `Mountain Pride' and `Sunbeam' tomato (Lycopersicon esculentum Mill.). Ethylene concentration in containers without ventilation significantly increased during storage at 5 °C, whereas little or no accumulation of ethylene occurred in containers with one or six perforations. Chilling injury was greatest for slices in containers with six perforations, compared to slices in containers with one perforation, and was over 13-fold greater than that of slices in control containers with no perforations. An experiment was also performed to investigate the effectiveness of including an ethylene absorbent pad in containers on subsequent ethylene accumulation and chilling injury. While ethylene in the no-pad controls increased continually during storage of both `Mountain Pride' and `Sunbeam' tomatoes at 5 °C under modified atmosphere conditions, no increase in accumulation of ethylene was observed in containers containing ethylene absorbent pads throughout storage. The ethylene absorbent pad treatment resulted in a significantly higher percentage of chilling injury compared with the no-pad control. In studies aimed at inhibiting ethylene production using AVG during storage of slices, the concentration of ethylene in control containers (no AVG) remained at elevated levels throughout storage, compared to containers with slices treated with AVG. Chilling injury in slices treated with AVG was 5-fold greater than that of controls. Further, we tested the effect of ethylene pretreatment of slices on subsequent slice shelf life and quality. In slices treated with ethylene (0, 0.1, 1, or 10 μL·L-1) immediately after slicing, ethylene production in nontreated controls was greater than that of all other ethylene pretreatments. However, pretreatment of slices 3 days after slicing resulted in a different pattern of ethylene production during storage. The rate of ethylene production by slices treated with 1 μL·L-1 ethylene 3 days after slicing was greater during storage than any of the other ethylene treatments. With slices pretreated with ethylene, both immediately and 3 days after slicing, the rate of ethylene production tended to show a negative correlation with chilling injury. Chemical name used: 1-aminoethoxyvinylglycine (AVG).
Ozone treatment has many advantages for control of fungal diseases. There are no residue concerns, no registration is required, and it is non-specific, therefore potentially effective against a broad spectrum of pathogens. However, ozone is known to cause plant damage. There is little information available on either the ozone tolerance of floriculture crops or the levels required to kill plant pathogens under commercial conditions. Nine floriculture crops (begonia, petunia, Impatiens, Kalanchoe, pot roses, pot chrysanthemums, lilies, snapdragons and Alstroemeria) were subjected to increasing levels of ozone. Trials were conducted at 5 and 20 °C (90% to 95% RH) and ozone exposure was for 4 days for either 10 hours per day (simulating night treatment) or for 10 minutes every hour. Damage was assessed immediately after treatment and after an additional 3 days at room temperature in ozone-free air. Trials were terminated for the crop when an unacceptable level of damage was observed. Trials to determine the lethal dose for actively growing pathogens (Alternaria alternata, Alternaria zinniae and Botrytis cinerea) and fungal spores were conducted under identical conditions. Ozone tolerance varied with plant type and ranged between <0.2 and 3ppm. Generally, the crops surveyed were more susceptible to ozone damage at the low temperature. As a group, the bedding plants were the least tolerant. Fungal spores were killed at treatment levels between 0.8 and 2 ppm ozone. The actively growing fungal mycelium was still viable at 3 ppm ozone when the trial had to be terminated due to ozone-induced structural damage in the treatment chambers. Under the trial conditions, only the Kalanchoe would be able to tolerate the high levels of ozone required to kill the fungal spores.
Abstract
Strawberry plants (Fragaria ×ananassa Duch. ‘Dover’ and ‘Florida Belle’) produced increased December fruit yields during 2 seasons when stored at 2°C for 1 week prior to transplanting rather than transplanting directly from the nursery. The total fruit yield of ‘Dover’ decreased with storage the 2nd season, whereas the total fruit yield of ‘Florida Belle’ was unaffected by storage. Lowering the soil fertility in the nursery prior to plant harvest increased ‘Dover’ December fruit yield the 2nd season, and increased ‘Florida Belle’ December yield both seasons. Total fruit yields of both cultivars as related to nursery fertility were inconsistent. Total fruit yields of ‘Dover’ in both seasons were greater with a fertilizer application in the fruit production field of 224N-50P-224K kg·ha-1 than with double this application. Total fruit yield of ‘Florida Belle’ was not affected by fertilization in a fruiting field. During the first season, both cultivars produced more misshapen fruit with the 448N-100P-448K kg·ha-1 application than with the 224N-50P-224K kg·ha-1 application.
Abstract
Root regeneration and time to first budbreak of two-year white ash (Fraxinus americana L.) seedlings were strongly correlated with the number of hours of chilling. Physiological dormancy of the buds was removed after approx 2500 hours of storage at 5°C and this coincided with the beginning of increased root regeneration potential. Increased periods of chilling enhanced the rate at which growth was resumed after transfer of seedlings to environmental conditions adequate for growth. The present study indicates that fall-harvested white ash seedlings can be stored at 5° at least until May without any apparent detrimental effects on root regeneration potential or seedling condition.