The multi-billion dollar US tree nut industries rely heavily on methyl bromide fumigation for postharvest insect control and are facing a major challenge with the mandated cessation by 2005 of its use for most applica...The multi-billion dollar US tree nut industries rely heavily on methyl bromide fumigation for postharvest insect control and are facing a major challenge with the mandated cessation by 2005 of its use for most applications. There is an urgent need to develop effective and economically viable alternative treatments to replace current phytosanitary and quarantine practices in order to maintain the competitiveness of US agriculture in domestic and international markets. With the reliable heating block system, the thermal death kinetics for fifth-instar codling moth, Indianmeal moth, and navel orangeworm were determined at a heating rate of 18℃/min. A practical process protocol was developed to control the most heat resistant insect pest, fifth-instar navel orangeworm, in in-shell walnuts using a 27 MHz pilot scale radio frequency (RF) system. RF heating to 55℃ and holding in hot air for at least 5 min resulted in 100% mortality of the fifth-instar navel orangeworm. Rancidity, sensory qualities and shell characteristics were not affected by the treatments. If this method can be economically integrated into the handling process, it should have excellent potential as a disinfestation method for in-shell walnuts.展开更多
The fruit development rules of two Chinensis Actinidia cultivars were studied in this paper. ‘Fengyue’has the same fruit development cycle as‘Cuiyu’. According to soluble solids content, there are four stages duri...The fruit development rules of two Chinensis Actinidia cultivars were studied in this paper. ‘Fengyue’has the same fruit development cycle as‘Cuiyu’. According to soluble solids content, there are four stages during fruit development phase named comparatively stable period, slow increase period, rapid increase period and stagnating increase period. Fruit firmness change exhibits two periods, i.e. slowly declining period and rapidly declining period. There is an obvious corresponding relation between the changes of fruit firmness and the soluble solids content, i.e. the rapidly declining time of fruit firmness corresponds with the rapidly increasing time of soluble solids content. According to the experiment, the best picking periods of ‘Fengyue’and ‘Cuiyu’are mid September to mid October and early October to early November, respectively.展开更多
文摘The multi-billion dollar US tree nut industries rely heavily on methyl bromide fumigation for postharvest insect control and are facing a major challenge with the mandated cessation by 2005 of its use for most applications. There is an urgent need to develop effective and economically viable alternative treatments to replace current phytosanitary and quarantine practices in order to maintain the competitiveness of US agriculture in domestic and international markets. With the reliable heating block system, the thermal death kinetics for fifth-instar codling moth, Indianmeal moth, and navel orangeworm were determined at a heating rate of 18℃/min. A practical process protocol was developed to control the most heat resistant insect pest, fifth-instar navel orangeworm, in in-shell walnuts using a 27 MHz pilot scale radio frequency (RF) system. RF heating to 55℃ and holding in hot air for at least 5 min resulted in 100% mortality of the fifth-instar navel orangeworm. Rancidity, sensory qualities and shell characteristics were not affected by the treatments. If this method can be economically integrated into the handling process, it should have excellent potential as a disinfestation method for in-shell walnuts.
文摘The fruit development rules of two Chinensis Actinidia cultivars were studied in this paper. ‘Fengyue’has the same fruit development cycle as‘Cuiyu’. According to soluble solids content, there are four stages during fruit development phase named comparatively stable period, slow increase period, rapid increase period and stagnating increase period. Fruit firmness change exhibits two periods, i.e. slowly declining period and rapidly declining period. There is an obvious corresponding relation between the changes of fruit firmness and the soluble solids content, i.e. the rapidly declining time of fruit firmness corresponds with the rapidly increasing time of soluble solids content. According to the experiment, the best picking periods of ‘Fengyue’and ‘Cuiyu’are mid September to mid October and early October to early November, respectively.
