Turfgrass seeds can be sown individually, in mixes, or overseeded to provide green color and uniform surfaces in all the seasons. This investigation was conducted to compare different turfgrass species and their seed mixtures. In this research, the turfgrasses—perennial ryegrass (Lolium perenne L. `Barball'), kentucky bluegrass (Poa pratensis L. `Merion'), common bermudagrass (Cynodon dactylon [L.] Pers.), and strong creeping red fescue (Festuca rubra L. var. rubra `Shadow')—in monoculture or in mixtures of 1:1 (by weight) and a 1:1:1:1 (by weight) and two sport turfgrasses—BAR 11 (Barenbrug Co.) and MM (Mommersteeg Co.)—were used. The seeds were sown in March and October (spring and fall sowing) in 1998 and 1999. The experiments were conducted in a split-split block design with year as main plot, sowing season as subplot, and turfgrass types as subsubplot. The turfgrasses were compared by measuring visual quality, chlorophyll index after winter and summer, rooting depth, verdure and/or root fresh and dry weight, tiller density, and clippings fresh and dry weight. Fall sowing was superior to spring sowing and resulted in greater root growth, clipping yield, and chlorophyll content. Poa+Cynodon seed mixture was the best treatment and had high tiller density, root growth, and chlorophyll content. Lolium and Festuca monocultures, and Poa+Festuca and Cynodon+Festuca seed mixtures were not suitable with regard to low tiller density, sensitivity to high temperatures, low root growth, and low tiller density, respectively. The cool-warm-season seed mixture (Poa+Cynodon) can be used alternatively in overseeding programs in the areas with soil and environmental conditions similar to this research site.
Hassan Salehi and Morteza Khosh-Khui
Kenneth E. Conway, John M. Dole, Theresa L. Bosma and Niels O. Maness
Field seedling emergence of four african marigold (Tagetes erecta) breeding lines, A-975, E-1236, I-822, and `Orange Lady', was examined using three or four spring sowing dates and either osmotic or solid matrix priming. Delayed sowing decreased emergence time. Sowing from middle to late April [average soil temperatures 77.0 to 84.2 °F (25 to 29 °C)] resulted in the highest total emergence percentages. Greater fl ower quantities [4.9 to 5.1 million/acre (12.11 to 12.60 million/ha)] and estimated yield [7.5 to 10.8 tons/acre (16.81 to 24.20 t·ha-1)] indicate mid to late April is the optimum time period for direct sowing unprimed seed in the southern Great Plains. Differences between lines were evident in emergence parameters and fl ower harvest data for each year examined, but results were inconsistent from year to year. However, A-975 and E-1236 produced harvestable fl owers most quickly, about 15 d before I-822, which could result in an additional harvest during a season. Osmotic priming of E-1236 and I-822 seed shortened emergence time, increased emergence uniformity, and increased total emergence percentage at early sowing dates as compared to both solid matrix primed and unprimed seed.
Hans C. Wien
Ornamental sunflower (Helianthus annuus) cultivars grown as cut flowers range in sensitivity to photoperiod with regard to flowering from facultative short day (SD) to facultative long day (LD), with others insensitive to daylength. SD sensitivity is a problem for production in tropical areas, or in early spring sowings when the daylength triggers early flowering, and leads to small flowers and production of unsightly axillary buds. In the current work, 59 cultivars of sunflower were exposed to either 12- or 16-hour photoperiod in seedling trays in a greenhouse for 3 weeks, and transplanted outside. At flowering, plant height, leaf number, and flower diameter were measured. The studies were conducted in 2006, 2007, 2009, 2011, and 2012 with two cultivars (Procut Lemon and Sunrich Orange) serving as controls in each trial. Of the 59 cultivars screened, 52% were found to be day-neutral, 44% were SD, and two (3%) had a LD reaction. Two standard cultivars grown in each season showed consistent reactions to the photoperiod treatments in each year. The seedling screen is useful to identify cultivars suited for production in early spring in a temperate environment.
A. Douglas Brede
green is under daily golf play and maintenance. Bigelow and Chalmers (1995) studied interseeding into mature annual bluegrass using a 1980s creeping bentgrass cultivar, ‘Southshore’ ( Hurley et al., 1994 ). They found that spring sowing resulted in
Davut Keleş, Ceren Özcan, Hasan Pınar, Atilla Ata, Nihal Denli, Namık Kemal Yücel, Hatıra Taşkın and Saadet Büyükalaca
, petioles are short, and leaf blades are large and fleshy. The variety is suitable for autumn and especially spring sowing. It is resistant to four races of spinach downy mildew. It has either hermaphrodite flowers or is dioic. Koto F1 is an early, high