Five species and 27 cultivars of fine-leaved fescues (Festuca sp.) were evaluated for low-maintenance utility turf in a variety of golf course conditions. Cultivar selection and management techniques varied across six sites in 4 years. Germination, tillering, rapidity of establishment, turf density, and general turfgrass quality were significantly different between both species and cultivars. Annual and seasonal decline and recovery of turf quality was also dependent on both species and cultivar. Greater differences exist within cultivars in some species than between species. Aspect, slope, soil disturbance, shade, seeding date, irrigation, fertility regime, mulch, and mowing influenced establishment and seedling development. Absence of endophytic fungi and development of diseases, insects, weeds, and post-germination disturbance markedly contributed to losses in turf quality, percent living cover, and increased erosion potential. Success and duration of fescue slope plantings are both positively and negatively correlated to various site characteristics and management techniques. Fescues are an appropriate choice in specific circumstances.
Mike L. Grant, Diana M. Miller, and Alastair Culham
Knowledge of the origin of Lavatera L. (tree mallows) cultivars helps to predict their cultural requirements. Eighteen accessions representing 15 cultivars, 14 accessions of 7 species, and 5 accessions of an F1 hybrid between the putative parents of the cultivars were sampled for morphological variation and for randomly amplified polymorphic DNA (RAPD) fingerprint variation. Species-specific molecular markers were identified from the RAPD profiles. Chimeral elements were not distinguishable by RAPD analysis. Principal component analysis identified the majority of the cultivars to be selections of hybrid origin, probably from a narrow genetic base. Two cultivars were derived directly from individual species. The resolving power of RAPD markers and morphology was similar although RAPD data offered greater ability to ascribe parentage while morphology offered optimal discrimination of cultivar selections.
Leslie A. Weston and M.M. Barth
Vegetables provide a major source of essential vitamins such as ascorbic acid and beta carotene and other quality components in the human diet. Postharvest yield and quality of vegetables depend upon genetic, biotic, edaphic, chemic and other factors, as well as combinations of these factors. Successful production, quality and nutritional value of vegetables are related to both primary and secondary metabolic processes occurring during vegetable growth and development. Related research has focused upon cultivar selection, cultural practices used during production, interaction of light and temperature, and use of chemicals for growth regulation, and pest control. We will discuss the effects of genetic, pest, and soil management; crop maturity at harvest; environmental modification; and climatic conditions. Postharvest vegetable quality will be characterized in terms of vitamin content, appearance, yield, and flavor.
Andrew G. Reynolds, Margaret Cliff, Douglas A. Wardle, and Marjorie King
Eighty-five cultivars, selections and clones from European winegrape (Vitis spp.) breeding and selection programs were evaluated between 1993 and 1995 in a randomized complete-block experiment. These included Vitis vinifera clones from France as well as Freiburg, Geisenheim, and Weinsberg, Germany. Small yield and fruit composition differences were found amongst the 'Chardonnay' clones. The standard Prosser clone produced wines with highest earthy aroma and acidity and with lowest perfumy aroma, body and finish; Dijon clones 76 and 96 were most perfumy and least vegetal. `Pinot noir' clones also differed somewhat in terms of yield and fruit composition; `Samtröt', `Gamay Beaujolais', and clone Q1342-01 were amongst the most highly colored clones. These clones also tended to have the most intense berry and currant aromas as well as berry, cherry, and currant flavors. These aforementioned clones appear to be highly adaptable to viticultural regions where low heat units during fruit maturation presently limit industry growth.
Anne K. Carter and Charles S. Vavrina
The germination of five commercial cultivars of jalapeño and cayenne pepper were tested to determine cultivar response of Capsicum annuum L. to supra-optimal temperatures. Two seedlots of `Cayenne, Large Red Thick', `Ole', `Jalapeño M', `Mitla', and `Tam Veracruz' were evaluated on a thermogradient table at temperatures of 20, 25, 30, 35, and 40 °C. Percent germination and time to 50% of final germination (T50) were calculated. All cultivars exhibited thermodormancy, but the degree of inhibition varied within temperature and cultivar. No cultivar had >1.0% germination at 40 °C. Generally, the T50 varied among cultivars, but not among temperatures within a cultivar (T50 at 40 °C was not measured). Cultivar selection should be considered when growing fall transplants in Florida.
Chih-Cheng T. Chao, Dan E. Parfitt, and Themis J. Michailides
Pistachio (Pistacia vera L.) progeny were evaluated at two locations in California for resistance to alternaria late blight caused by Alternaria alternata (Fries) Keissler in 1995 and 1997. Large differences in alternaria late blight infection among seedlings were observed. Narrow sense heritabilities based on half-sib analysis of 20 open pollinated families were 0.48 and 0.11 at Kearney Agricultural Center in 1995 and 1997, respectively, and 0.56 and 0.54 at the Wolfskill Experimental Orchard near Davis in 1995 and 1997, respectively. Differences among families to alternaria late blight infection were highly significant and associated with the female parents. Fifty-eight highly resistant seedlings were identified for future cultivar selection efforts.
W. E. Ballinger and W. B. Nesbitt
Nine cultivars/selections of muscadine grapes (Vitis rotundifolia Michx.) were stored for 49 days at O°C in 6 liter telescoping, corrugated-cardboard shipping containers with polyethylene liners, and 3 types of commercially available SO2 generators. Susceptibility to decay during storage varied greatly among selections (7 to 82% decay without SO2). The SO2 generators produced up to 29 ppm SO2 and all 3 types reduced decay. The genotypes also varied widely in their tolerance of SO2. Placement of newspaper in the shipping containers reduced the concentrations of SO2, reduced SO2 damage to the fruit by up to 74%, and had an inconsistent influence on the development of decay. Fruit of selection NC 67A015-17 appeared to be the best suited for long-term storage.
Kari L. Hugie and Eric Watkins
four replications. Mowing height was the main plot, nitrogen rate was the sub plot, and cultivar/selection was the sub-sub plot (individual plot size 1.0 × 1.5 m). A starter fertilizer (24.5 kg N/ha; 21.6 kg P/ha; 23.7 kg K/ha) was applied at seeding
Desmond R. Layne*, W.R. “Dick” Okie, and Eric J. Hitzler
The evaluation of peach and nectarine cultivars and advanced selections for suitability of production in the southeastern U.S. has been conducted at Clemson Univ. since 2000. Currently, there are 240+ cultivars and advanced selections being tested at the university's Musser Fruit Farm in Seneca, S.C. The harvest season begins in early May and ends in the middle of September. Additionally, two on-farm grower trials were planted in the primary peach growing regions of the Piedmont (Cowpens, S.C.) and the Ridge (Monetta, S.C.). At the grower locations, advanced selections are compared with industry standard cultivars. Evaluation data collected includes bloom and ripe date, fruit set, shape, color, size, firmness, taste and disease susceptibility. Digital photos are taken to scale at commercial maturity. Evaluation information, photos, plus chill hours, variety descriptions and other valuable information are on the website. In 2004, substantial improvements were made to the site utilizing a database, search and compare tools. The website has been well received by the southeastern commercial peach growers and is utilized to assist them in cultivar selection and to learn more about peach culture in general.
S.B. Sterrett and C.P. Savage Jr.
Commercial production of bunched broccoli on the Eastern Shore of Virginia has been limited because of shortened internodes resulting in thick, tough stalks. A field study was completed to examine the influence of plant type (transplants or direct seeded), plant population (5800 or 8700 plants/ha), and N application (112 kg/N with zero, one, or two sidedress applications of 40 kg·ha–1) on marketable yield, head diameter, and stem diameter of `Packman' broccoli. None of the measured characteristics improved significantly with sidedress N application. Marketable yield and average head weight were significantly correlated (P = 0.01) to the total number of heads harvested (r = 0.70 and r = –0.91, respectively). More heads were harvested for the high population, direct-seeded treatment and fewer for the low-population transplants. Average stem diameter of transplants was slightly greater than that of direct-seeded broccoli being significant (P = 0.05) in the second and third harvests. However, few stems were of commercially acceptable diameter regardless of treatment combination. Additional evaluation of cultural management strategies and cultivar selection is needed to successfully promote commercial production of bunched broccoli in this growing area.