Pre-harvest Fungal Colonization Affects Storage Life of Bing Cherry Fruit

Treatment of sweet cherry ( Prunus avium cv. Bing) trees with either two mildewcide cover sprays or multiple (18) applications of topical and systemic fungicides produced cherry fruit that were either highly colonized or relatively uncolonized by fungi, respectively. Fruit from the multiple application treatment had a storage life of up to 8 weeks (7 weeks at 1-4°C plus 1 week at simulated retail temperatures of 20–21°C), whereas the commerciallymanaged fruits (two mildewcides) were extensively colonized by fungi and extensively decayed when stored under the same conditions. Stringent post-harvest disinfection did not significantly reduce postharvest decay, and only slightly reduced isolation frequency of fungi. The data obtained in this study suggest that the degree of preharvest fungal colonization is a primary determinant of the percentage of post-harvest decay, and that pre-harvest colonization can potentially be addressed by pre and post-harvest management practices.     

The molecular and metabolic program by which white adipocytes adapt to cool physiologic temperatures

Although visceral adipocytes located within the body’s central core are maintained at approximately 37°C, adipocytes within bone marrow, subcutaneous, and dermal depots are found primarily within the peripheral shell and generally exist at cooler temperatures. Responses of brown and beige/brite adipocytes to cold stress are well studied; however, comparatively little is known about mechanisms by which white adipocytes adapt to temperatures below 37°C. Here, we report that adaptation of cultured adipocytes to 31°C, the temperature at which distal marrow adipose tissues and subcutaneous adipose tissues often reside, increases anabolic and catabolic lipid metabolism, and elevates oxygen consumption. Cool adipocytes rely less on glucose and more on pyruvate, glutamine, and, especially, fatty acids as energy sources. Exposure of cultured adipocytes and gluteal white adipose tissue (WAT) to cool temperatures activates a shared program of gene expression. Cool temperatures induce stearoyl-CoA desaturase-1 (SCD1) expression and monounsaturated lipid levels in cultured adipocytes and distal bone marrow adipose tissues (BMATs), and SCD1 activity is required for acquisition of maximal oxygen consumption at 31°C.

Adipocytes in bone marrow, subcutaneous and dermal sites generally exist at temperatures below 37°C. This study identifies the molecular and metabolic program that adapts white adipocytes to these cooler environments.