Search Results
Preservation of genetic diversity is of paramount importance in germplasm. A method of collecting, storing, and organizing genetic material to include maximum variability and to minimize repetition within the collection is a “core collection.” To assist the National Plant Germplasm System in developing a core collection, or core subset of Capsicum germplasm, field evaluations were conducted from 1989 to 1993 at New Mexico State University. In determining how best to organize the core subsets, we believe the objectives of a Capsicum core subset should be to increase the efficiency of evaluation and thus the utilization of existing collections and to provide for a manageable and representative selection of available Capsicum germplasm for use in research and plant breeding. We are using a modified IBPGR Capsicum descriptor list to evaluate the collection, With these objectives in mind, we are suggesting the following approach to Capsicum core subsets. At least one accession of each Capsicum species is contained in the core. The most economically important species, C. annuum, represents the majority of accessions. Within C. annuum the core subsets are grouped by pod-type (ancho, bell, jalapeno, etc.). The pod-type is analogous to races in maize (Zea mays).
Abstract
Seed weight, germination, seedling emergence, and yields were examined following desiccation of southernpea [Vigna unguiculata (L.) Walp cv. Mississippi Purple] plants with glyphosate [N-(phosphonomethyl)glycine]. Dry seed weight was not reduced by the desiccation process; however, seed quality of those treated at immature stages was reduced. Germination, seedling emergence, and yield from seed desiccated at immature stages were significantly less than from seeds desiccated at more mature stages of development. No differences were apparent between desiccation at mature stages and the control.
The objective of this study was to determine the most advantageous time to collect cuttings of Chinese pistache, a commonly recommended ornamental shade tree that is difficult to propagate by cuttings. In 1993, calendar date and degree days (daily mean temperature -7.2C) were used to estimate an appropriate cutting time. The greatest percentage of rooted cuttings occurred in male cuttings harvested on 13 May 1993 (397 degree days) and treated with 17,500 mg·liter-1 IBA or in male cuttings harvested on 20 May 1993 (482 degree days) and treated with either 8750 or 17,500 mg·liter-1 IBA. In 1994, cutting time was associated with calendar days, degree days, and morphology. The most rooted cuttings (44%) were from green softwood cuttings taken on 9 May 1994, which was 380 degree days from orange budbreak using a threshold temperature of 7.2C. Orange budbreak was characterized by separation of the outer bud scales such that the orange, pubescent inner bud scales were visible. Cuttings taken on 9 May 1994 and treated with 8750 mg·liter-1 IBA produced the most primary and secondary roots and the longest primary roots per cutting. Male Chinese pistache cuttings should be collected from green softwood or red semi-softwood stems when about 380 to 573 degree days have accumulated after orange budbreak. Chemical names used: indolebutyric acid (IBA).
The effectiveness of shade intensity and time of day in which irrigation was applied were tested for control of anthracnose symptoms caused by Colletotrichum gloeosporioides (Penz.) Penz. & Sacc. on container-grown Euonymus fortunei (Turcz.) Hand.-Mazz. `Canadale Gold', `Emerald 'n Gold', and `Emerald Gaiety' during the 2002 and 2003 growing seasons. Rooted cuttings in 3.8 L containers were placed in 0% (full sun), 63%, 73%, or 80% shade at Park Hill, Okla., in 2002 and 2003 and at Stillwater, Okla., in 2002. Overhead irrigation was used to irrigate one-half of the plants in each cultivar and shade treatment in the morning and the other one-half during the afternoon. At both sites, disease damage ratings were inversely related to shade intensity throughout each growing season. Disease incidence was usually lower on afternoon irrigated plants than on morning irrigated plants. `Canadale Gold' typically had the most anthracnose symptoms followed by `Emerald 'n Gold'. `Emerald Gaiety' had the least symptoms regardless of shade intensity or irrigation time.
Using fish culture waste water may benefit vegetable production by reducing the need for high quality irrigation water. Fish waste water also contains nutrients, reducing the need for chemical fertilizers. A study was conducted to integrate fish (tilapia) culture with field production of bell pepper (Capsicum annuum L.). Waste water from low and high fish stocking densities and variable water exchange rates were applied to bell peppers 2 to 3 times weekly. These treatments were compared with fish sludge. cow manure and commercial N fertilizer. Fish waste water and sludge were applied by hand in the first year. A modified irrigation system was used in the second year. All other treatments were drip irrigated. In 1992 marketable yield was highest (9.0 t/ha) in plots with N fertilizer (drip fertigation) followed by plots applied with sludge (5.0 c/ha). Lowest yield (2.0 t/ha) was obtained from plots applied with fish waste water. In 1993 plots applied with fish waste water had a slightly higher yield (7.0 t/ha) than N-fertigated plots. Marketable yield was highest (10.4 t/ha) in plots treated with sludge.