Nodal segments of Hibiscus moscheutos (hardy hibiscus) were excised from proliferating axillary shoot cultures and encapsulated in high density sodium alginate hardened by 50 mM CaCl 2 . Nodal segments 4 mm long grew as well as and were easier to encapsulate than 8 mm long nodal segments. Although nodal segments grew regardless of the concentration of sodium alginate, 2.75% was determined to produce the highest quality encapsulated nodal segments beads (sufficient alginate coating and ease of use) because of the viscosity produced by the 2.75% sodium alginate solution. When encapsulated segments were stored at 5°C they did not grow in light or darkness. During the first month on fresh proliferation medium under normal incubation conditions following 5°C storage in the dark for up to 24 weeks, root number and root and shoot elongation were inhibited linearly as storage time increased. All encapsulated nodal segments survived 24 weeks of 5°C storage in two separate experiments. In fact, 80% of encapsulated hardy hibiscus nodal segments survived refrigerated storage for 1½ years (78 weeks) and after 3 months on proliferation medium, the nodal segments produced nearly the same length axillary shoots with the same number of axillary nodes per shoot as compared to encapsulated segments either not stored at 5°C or stored for 24 weeks at 5°C. Growth from encapsulated and cold-stored 'Lord Baltimore' nodal segments was more vigorous than from 'Southern Belle' nodal segments.

A cleptoparasitic mite, the Krombein's hairy-footed mite, Chaetodactylus krombeini Baker (Acari, Chaetodactylidae) became a key pest that affects the maintenance and propagation of Osmia spp. (Hym., Megachilidae), thus disrupting orchard pollination in the United States. Although hypopi, the dispersal stages of C. krombeini, are known to disperse from nest to nest by hitchhiking on Osmia cornifrons adults, we observed that they might disperse in other ways too in commercial orchards. This study was conducted to elucidate the nest-to-nest dispersal mechanisms of C. krombeini hypopi. We tested three potential dispersal mechanisms of C. krombeini other than phoresy by O. cornifrons: (1) dispersal by walking from nest to entrances of nearby nests, (2) dispersal by walking from nest to nest through emergence holes made by parasitic wasps on nests, and (3) dispersal by being unloaded and uptaken to and from flowers by O. cornifrons. Results of this study showed that C. krombeini hypopi could disperse from a nest to nearby nests by walking through nest entrances and holes made by parasitic wasps of O. cornifrons. Although 0.06% of C. krombeini hypopi on blueberry flowers were picked up by O. cornifrons, they were not able to be unloaded to flowers from O. cornifrons and no hypopi could inhabit or survive on blueberry flowers. This indicated no or very low chance of C. krombeini hypopi dispersal via blueberry flowers. Based on our findings of C. krombeini dispersal ecology, development of C. krombeini control strategies are discussed in this article. *There were no statistical differences between nests with and without pollen provisions based on paired Student's t-tests at a = 0.05 (SAS Institute 2008). Average (AESD) number of C. krombeini hypopi per nest and percentage (AESD) of nests infested with C. krombeini hypopi are presented in this table.

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Production and nutrient removal were assessed for three vegetable crops (kohlrabi, lettuce, and Swiss chard) and two edible flowers (calendula and nasturtium) grown entirely on effluent from a flow-through trout raceway. Soluble nutrient concentrations in the effluent averaged 0.56 and 0.19 mg/L for total nitrogen and soluble reactive phosphate, respectively. Seeds were sown into Styrofoam trays filled with vermiculite and placed directly into the plant growing channels. Lettuce was harvested at 6, 9, and 12 weeks for a total mean harvest biomass of 4.5 kg/m 2 . Kohlrabi and Swiss chard were harvested at 12 weeks, with a mean harvest biomass of 15.4 and 7.5 kg/m 2 , respectively. Harvest biomass of kohlrabi was significantly greater than that of lettuce or Swiss chard. Nasturtium flowers were harvested at 9 and 12 weeks, while calendula did not begin to produce flowers until 12 weeks. There were no significant differences in percent removal of total ammonia nitrogen (TAN), nitrate, or phosphate at 6 weeks. However, at 9 weeks, kohlrabi, Swiss chard, and nasturtium removed significantly more TAN and nitrate than lettuce and calendula. Total ammonia nitrogen removal decreased at 12 weeks while nitrate removal increased for kohlrabi, Swiss chard, and calendula. Phosphate removal was low for all cultivars and may be the result of high phosphate concentrations in the source water. Careful crop selection will be necessary to maximize the benefits of aquaponics as crops varied in growth rates, overall nutrient removal capacity, and timing of nutrient removal.