Sweetpotato [Ipomoea batatas (L.) Lam., `Beniazuma'] plantlets were grown photoautotrophically (without sugar) for 12 days in an improved forced ventilation system designed with air distribution pipes for uniform spatial distributions of carbon dioxide (CO2) concentration. Enriched CO2 conditions and photosynthetic photon flux (PPF) were provided at 1500 μmol·mol-1 and 150 μmol·m-2·s-1, respectively. The forced (F) ventilation treatments were designated high (FH), medium (FM), and low (FL), corresponding to ventilation rates of 23 mL·s-1 (1.40 inch3/s), 17 mL·s-1 (1.04 inch3/s), and 10 mL·s-1 (0.61 inch3/s), respectively, on day 12. The natural (N) ventilation treatment was extremely low (NE) at 0.4 mL·s-1 (0.02 inch3/s), relative to the forced ventilation treatments. Total soluble sugar (TSS) and starch content were determined on day 12. Total soluble sugars (sucrose, glucose, fructose) of FH plantlets were lowest in leaf tissue and highest in stem tissue as compared to other ventilation treatments. Starch concentration was higher in leaf tissue of FH or FM plantlets as compared to that of FL or NE plantlets. Plantlets subjected to FH or FM treatments exhibited significantly higher net photosynthetic rates (NPR) than those of the other treatments; and on day 12, NPR was almost five times higher in the FH or FM treatment than the FL or NE treatments. Carbohydrate concentration of plantlets was also influenced by the position of the plantlets in the vessel. Within the forced ventilation vessels, leaf TSS of FH and FM plantlets was similar regardless of whether plantlets were located near the inlet or outlet of CO2 enriched air. However, under FH or FM conditions, leaf starch concentration was higher in plantlets located closest to the CO2 inlet as compared to the outlet.
artificial shade conditions. Materials and Methods Experiments were conducted in 2006 and 2007 at the Texas Tech University Horticulture Greenhouse in Lubbock, TX. Plugs measuring 2.5 cm 2 of six zoysiagrass genotypes [ Zoysia japonica Steud. genotype
osmotic regulation resulting in higher turgor pressures. The present study was conducted to evaluate the recuperative potential of transplanted plugs of 24 commonly grown cultivars of three species of warm-season turfgrasses subjected to varying amounts of
) compared the establishment rate and stolon growth characteristics of five Z. japonica lines, ‘Emerald’, and a Z. matrella cultivar in Maryland. When planted as 5-cm diameter plugs on 30-cm centers, ‘Midwest’, a Z. japonica , and Bel-Zrt-1, an
the existing sod and replacing sod of a warm-season species would be the ideal remedy, but this may be cost prohibitive for many homeowners and facilities. An alternative approach would be to seed or plug the warm-season species directly into the
1 E-mail blackb@ba.ars.usda.gov . The author gratefully acknowledges student intern Michele Sumi for technical assistance, Davon Crest Farms for supplying strawberry plug plants, and BASF Corp. for providing prohexadione-Ca. Mention of a trademark
seedlings and cuttings are established, and a finish plant stage, in which the young plants are transplanted into a larger container and grown until marketable ( Ball, 1998 ). During the young plant stage, seedling plugs are typically produced during the
Lavender’ (Kieft-Pro-Seeds), ‘Sorbet Yellow Delight’, or ‘Sorbet Babyface Purple’ (PanAmerican Seed) were used in the experiments as described subsequently. Plugs (young plants in the vegetative stage) were obtained from Green Circle Growers Inc. (Oberlin
plants from seeds is the formation of a firm root plug; i.e., one in which the root system remains intact when removed from the container ( Landis, 2014 ). Because milkweed plants develop rhizomes without many fibrous roots, transplanting or outplanting
. Restoration plantings have occurred at conservation areas, state and city parks, national wildlife refuges, shorelines, nature preserves, and hurricane protection levees. Nearly 20,500 student-grown plants from 13 shrub and tree species and 8000 plugs from two