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M.S. Stanghellini, J.R. Schultheis, and J.T. Ambrose

Very little is known about the rate at which pollen grains are mobilized within insect-pollinated crop systems, and this is especially true the for commercial production of field-grown cucumber (Cucumis sativus L.), monoecious muskmelon (Cucumis melo L.), and triploid watermelon [Citrullus lanatus (Thunb.) Matsum. & Nakai]. The rates of pollen depletion for these crops were therefore investigated on plots simulating commercial crop production using a mixed honey bee (Apis mellifera L.) and bumble bee (Bombus impatiens Cresson) pollinator complex. At anthesis, staminate cucumber, muskmelon, and watermelon flowers contained on average 10539, 11176, and 30739 pollen grains/flower, respectively. At the time flowers closed in the early afternoon (1300 to 1400 hr), only 61% of the total pollen produced had been removed from staminate cucumber flowers, 44% to 62% from muskmelon, and 81% from watermelon flowers. The results suggest that total pollen production in these crops may not necessarily reflect total pollen availability to floral visitors (bees). However, of the total amount of pollen actually removed per flower, >57% occurred during the 2 h following flower anthesis of cucumber and muskmelon, and >77% occurred during the 2 h following flower anthesis of watermelon. Thus, most of the accessible pollen was removed shortly after anthesis, which is when these crops are most receptive to pollination. Nonviable triploid and viable diploid watermelon pollen were removed at similar rates (P = 0.4604). While correlation analyses were not possible for the influence of variable bee abundance on pollen depletion rates, higher bee populations in one year appeared to increase the rate at which pollen grains were removed from staminate flowers.

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Heather L. Papinchak, E. Jay Holcomb, Teodora Orendovici Best, and Dennis R. Decoteau

foliage plants in controlled chambers (that simulated indoor environments) for their ability to reduce concentrations of several air pollutants. Depletion rates of known concentrations of air pollutants within the enclosed chambers containing plants were

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Jeff Kuehny, Mary Halbrooks, and Charles Graham

Current recommendations for sufficiency of nutrients in soil-less media for container grown nursery crops have been based on weak acid extraction and pour through sampling of media. Since the concentration of nutrients found in pour through samples are similar to those available in the media solution, sufficiency levels as determined by hydroponics studies have also been considered to be applicable to plants grown in a solid medium such as pine bark. Many variables, however, may affect nutrient availability in a solid medium which are not the same as those in a well-stirred hydroponics system. Objectives of this experiment were to compare growth and nutrient uptake patterns of Euonymous kiautschovica `Manhattan' and Prunus persica `Jefferson' grown in a pine bark/sand medium or a hydroponics system. Quantitative growth characteristics, depletion rates of nutrients in solution, concentration of ions in pour through samples, and tissue levels of N, P, K, Ca, and Mg will be reported.

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time ranged from 38 to 120 min per evaluation. Ozone depletion rates were higher within chambers that contained plants than within control chambers without plants, but there were no differences among plant species. Ophiopogon Species Cultivated in the

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Joan R. Davenport, Robert G. Stevens, and Kelly M. Whitley

systems Irr. Sci. 15 147 152 Stevens, R.M. Harvey, G. 1996 Soil water depletion rates under large grapevines Aust. J. Grape Wine Res. 2 155 162

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S. Alan Walters and Jonathan R. Schultheis

171 Stanghellini, M.S. Schultheis, J.R. Ambrose, J.T. 2002 Pollen mobilization in selected cucurbitaceae and the putative effects on pollinator abundance on pollen depletion rates J. Amer. Soc. Hort. Sci. 127 729 736 Thomson, J.D. Plowright, R.C. 1980

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Qi Chai, Fang Jin, Emily Merewitz, and Bingru Huang

). Results and Discussion Soil water status during drought and re-watering. Soil water content was measured as an indication of soil water status and it also provides a good estimate of the water depletion rate of a plant ( Kirkham, 2005 ). SWC in a

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Maria Victoria Huitrón, Manuel Diaz, Fernando Diánez, Francisco Camacho, and Antonio Valverde

.T. 2002 Pollen mobilization in selected Cucurbitaceae and the putative effects of pollinator abundance on pollen depletion rates J. Amer. Soc. Hort. Sci. 127 729 736 Talon, M. Zacarías, L. Primo-Millo, E

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Stephen E. McCann and Bingru Huang

-treated Kentucky bluegrass and TE-and ABA-treated creeping bentgrass at 13 d of drought, suggesting that TE or ABA treatment may result in lower water depletion rates due to growth inhibition during the early phase of drought. Previous studies evaluating Kentucky

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Xiuju Bian, Emily Merewitz, and Bingru Huang

untreated control plants ( Fig. 2 ). These results suggest that TE application reduced water use measured as total water loss through ET in creeping bentgrass, which was reflected by the slower water depletion rate from the soil, allowing plants to avoid