You are looking at 1 - 10 of 18 items for
- Author or Editor: J. E. Motes x
Yield, spear weight, and spear number of Asparagus officinalis L. were either unaffected or increased at 2 locations in subsequent years when plants were first harvested 1 year after planting crowns as compared to plants first harvested 2 years after planting crowns.
Fresh market tomato cultivar and cultural trials are conducted yearly at the Oklahoma Vegetable Research Station near Tulsa. From 14 to 18 cultivars have been evaluated each season since 1985 comparing the Florida stake-and-weave and the wire mesh cage cultural systems. Results from 7 years of trials indicate caging produced 32% greater marketable yield than the stake-and-weave system. Percentage early yield was reduced with the cage system. Percentage of cull fruit was greater with the stake-and-weave system due to a higher incidence of fruit cracking. Average fruit size was not affected by cultural system. Cost of production analysis showed a lower cost of production with the cage system. The cage system is more capital intensive and the stake-and-weave system is more labor intensive. Undesirable factors in the use of cages are greater difficulty in picking the early fruit clusters, logistics in off-season storage of cages and the larger capital investment required for the cage system.
Seed germination of pepper (Capsicum annuum L.) in aerated water columns was accelerated and germination uniformity improved by using gibberellic acid (GA3) at 6 μg/mg seed with 50 to 75 mg seed/ml of solution. Higher GA3 rates in the aerated columns reduced germination percentage in some cultivars. Detrimental effects for GA3 up to 6 μg/mg seed were not observed and in some cultivars speed of emergence and seedling growth was stimulated. GA3 is economically feasible for use in germinating pepper seeds for sowing using the fluid drilling technique.
‘Kennebec’ and ‘Irish Cobbler’ potatoes were irrigated when 1/3 or 2/3 of available soil moisture was depleted in a 3-year study. Control plots were not irrigated. Soil temperatures at 4-inch depth were equal in irrigated and non-irrigated soils one year and 2° and 7°F (1.1° and 3.9°C) cooler in irrigated soils the other 2 seasons.
U.S. No. 1 yield of ‘Kennebec’ was greater with irrigation when 1/3 available moisture was depleted in a low rainfall and high temperature season. ‘Irish Cobbler’, the same season, produced greatest yield by irrigating when 2/3 available moisture was depleted. Number of U.S. No. 1 tubers differed between seasons and followed yield trends. Specific gravity and number and weight of tubers were all inversely related to air and soil temperatures. Air and soil temperatures apparently are the major factors affecting potato yield under Kansas growing conditions.
The objective of this study was to evaluate the possible causes for greater pungency in pepper (Capsicum annuum) pods of two chile selections when produced at eastern and western Oklahoma locations. Pungency tests over several years have demonstrated that peppers grown in western Oklahoma consistently produce pods with ≈25% greater pungency than peppers grown in eastern Oklahoma. Data from Oklahoma Mesonet stations located near each production location indicated the western Oklahoma location had higher temperatures and wind speed but lower relative humidity than the eastern Oklahoma location during pod development. Mature dry pods were dissected into cap and stem, seeds, and pod wall. Comparisons of pod component differences between the locations showed pods were similar in dry weight; however, western Oklahoma produced more cap and stem in both selections, and in one selection produced more pod wall but less seed. Pungency was 24% and 28% greater in the two selections when grown in western Oklahoma. More pod wall and less seed could account for some of the pungency increase in only one of the selections. The more stressful production environment in western Oklahoma appears to be the major factor in pungency differences between the locations.
Research involving fluid drilling, the metering and planting of germinated vegetable seeds suspended in a gellike fluid, has been underway for several years (1, 3). A hand-operated, ground-driven, combination fluid drill and dry seed planter for small plot work (Fig. 1) is currently being used as a result of a joint project of the Oklahoma State University Agricultural Engineering and Horticulture Departments. The design is similar to machines described by Lickorish and Darby (2) and by W. L. Albring3 incorporating both a fluid metering unit and a cone-type dry seed metering unit into a single light-weight machine to expedite the planting of dry and germinated seed plots using the same furrow opener. Ease of operation and adjustment was considered during the design along with reliability and durability. The machine can be quickly adjusted to apply fluid rates of 10, 20, 40, 60, 80, and 100 ml/m of row length and dry seed metering rates of 3, 6, 9, and 12 m of row length per cone revolution.
Seed of germinated celery, Apium graveolens L. (Dulce group) and pepper, Capsicum annuum L. were separated from ungerminated seed by density differences in a sucrose and water solution. The top (floating) fraction in both species had the highest percentage germination and percent and rate of emergence compared to either the bottom fraction or unseparated seed.
A problem associated with machine harvesting of pepper (Capsicum annuum L.) with a stripper-type harvesting mechanism is plant uprooting. Four soil bedding treatments were compared for effects on uprooting force of Chile and paprika direct field seeded at Bixby, Okla. in 1992 and 1993. Bedding treatments were: 1) no-bed; 2) no-bed with 5 cm of soil hilled to the bases of plants; 3) bedded preplant but bed not maintained throughout the growing season; and 4) bedded preplant and bed maintained throughout the growing season. At harvest plants were cut off 10 cm above the soil surface and uprooting force determined using a wire cable puller, spring scale, and a lever based on a fulcrum. Chile uprooting force was significantly influenced by bedding treatments only in 1993. Paprika uprooting force was influenced in both years. In three of the four studies, bedding treatments 2 and 4 produced plants more strongly anchored than treatments 1 and 3.
Two species of tomato, Lycopersicon chilense Dun. and Solanum pennellii Corr., which have drought-resistant characteristics, were compared to the commercial tomato, Lycopersicon esculentum Mill. cv. Campbell 1327, to evaluate the effects of water deficits on germination and early seedling growth at 25, 30, and 35°C. Five levels or water stress (0, −2, −4, −6, and −8 bars) were maintained by solutions of polyethylene glycol (PEG) 6000. Germination of dry seed was inhibited more by water stress than by growth of the germinated seedlings of each species. Germinated seed of all species were able to continue growth at 35° plus water stress at all levels, while germination under the same conditions was totally suppressed. The water-sensitive phase of germination occurred just prior to radicle emergence. Emergence was not affected by sowing germinated seed in a drying soil; but sowing dry seed under the same conditions resulted in a decrease in emergence. Germination and seedling growth of L. chilense and S. pennellii were more sensitive to water stress than L. esculentum at 25°. At 30 and 35°, L chilense, S. pennellii and L. esculentum had similar rates of germination and similar amounts of early seedling growth.
The effects of water deficits were examined on osmotic regulation of germinating seedlings of tomato (Lycopersicon esculentum Mill cv. Campbell 1327). Seed were germinated in aerated water and then grown for an additional 2 days in Petri dishes. The germinated seeds were then transferred to water potentials of 0 to −6 bars in 2-bar increments. Mannitol and water was used to obtain the desired water potential of the media. Water relations, growth rates and reducing sugars, non-reducing sugars, amino acids, proline, nitrates, phosphates, potassium, and electrical conductivity were determined for roots and shoots at different water stresses. As water stress increased, osmotic adjustment occurred in the roots which accounted for the maintenance of turgor and growth. During the same period, little adjustment occurred in the shoots and consequently growth decreased. Turgor potential was highly correlated with growth rates for both plant parts. All solutes measured, except proline, generally increased in the roots and decreased in the shoots as water stress increased. Proline increased in both plant parts during the same period. Thus, solute regulation occurred during water deficits. Osmotic regulation in germinating tomato seedlings appears to be an adaptive feature during periods of water stress.