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- Author or Editor: F. J. Sundstrom x
Abstract
Farm population in the 1880s was about 45% of the United States total population. Labor represented over 60% of total inputs whereas capital (machinery) was less than 20% of the total inputs used in United States agriculture. By the 1980s, farm population was less than 3%, labor input had dropped to less than 16%, whereas capital investments had risen to over 60% of total inputs. During this same 100 year period, United States farm output per hectare increased 5 times.
Abstract
Fertilizer K supplied as KC1, and Ca supplied as gypsum, interacted in their effect on yield and tissue composition of ‘Calhoun Gray’ watermelon [Citrullus lanatus (Thunb.) Matsum. & Nakai]. Increased rates of K significantly affected yield in a curvilinear manner. Response for K at varying levels of Ca had linear and either cubic and/or quadratic relationships. Increased rates of Ca reduced K uptake and yield. There was a highly significant inverse relationship between tissue K and tissue Ca. Although there was a significant K x Ca interaction on yield, individual element correlation coefficients with yield also were significant. Increased rates of fertilizer K increased rind thickness at watermelon equator, which was found to be related to watermelon rupture pressure. Ca and blossomend rind thickness had no influence on rupture pressure. K and Ca did not influence blossom-end rot, redness of flesh, or soluble solids of watermelon.
Abstract
Ten cultivars of cabbage (Brassica oleracea v. capitata) were grown in the fall and spring seasons. Cultivar differences in medial and longitudinal head diameter, core length and width, head firmness, and yield were significant within each season. Spring temperatures and daylengths seemed to be more favorable for greater crop production than fall conditions. Growing season significantly influenced head shape and core length. Head shape was conical in the fall, and rounder in the spring. Core elongation was significantly greater in the fall crop. Regression equations show that the percentage of weight loss during storage was lowest at 1°C, and increased with increasing storage temperature.
Abstract
Flooding of bell pepper (Capsicum annuum L.) for 96 hr at anthesis adversely affected plant growth. Average leaf size of the flooded plants was significantly less than that of nonflooded controls. Ratios of leaf dry weight to root dry weight indicated that flooding reduced root development more than leaf development. Mean photosynthetic rate over the 96-hr flooding period and the 72-hr post-flooding period was decreased by 62%. Viability, germination percentage, and average weight of seeds from flooded plants were significantly less than those of control plants. Pepper photosynthetic rate was correlated with seed weight, seed viability, and germination percentage. Reductions in seed viability as a result of soil flooding may, therefore, be attributable to reductions in the supply of photosynthates to the seed.
Abstract
Seeds of jalapeno (Capsicum annuum L.) and tabasco (Capsicum frutescens L.) peppers were placed in aerated distilled water for 9.5 or 8 hr, respectively, or primed for 144 hr in aerated 3.0% or 2.75% KNO3 solutions, respectively. After treatment, seeds from each replication were placed on moist filter paper in Petri dishes for germination tests, in rolled paper towels for radicle and hypocotyl development tests, or in 70-ml incubation jars for 24-hr respiration studies. All tests were maintained at 25C. Jalapeno seed germination percentage was not affected by seed priming, but the mean rate of germination was increased. Jalapeno hypocotyl development was advanced at 7 and 14 days following seed priming. Compared to the soak controls, primed jalapeno seed respiration rates were greater at 0.15 and 0.45 hr following removal from incubation solution, but were no different thereafter. Tabasco seed germination percentage and rate were positively influenced by priming treatment, but seedling hypocotyl development was only advanced at 7 days following treatment. Primed tabasco seed respiration rates were depressed significantly relative to the soak control, suggesting that priming treatment inhibits some aspect of seed metabolism during germination. These data support earlier observations that seed priming is not useful in tabasco field stand establishment efforts.
Abstract
All possible combinations of ethephon at 0, 5000, 10,000, and 15,000 ppm, and calcium as Ca(OH)2 at concentrations of 0, 0.01, 0.1, and 1 m were applied to Tabasco pepper (Capsicum frutescens L.). In the greenhouse, as ethephon rates increased, leaf retention percentages decreased. Over all ethephon rates, as Ca(OH)2 concentration increased, Tabasco leaf retention percentages increased. Ethephon-induced fruit abscission was greatest in less-mature fruit. Overall fruit retention percentages were greatest when ethephon was applied with either 0.1 or 1 m Ca(OH)2. In the field, when ethephon was applied without Ca(OH)2, leaf and fruit abscission was so great that data could not be recorded. When ethephon was applied with 0.1 m Ca(OH)2, percentages of orange and red fruit on the plant increased with an increase in ethephon rate. Chemical name used: (2-choloroethyI)phosphonic acid (ethephon).
Abstract
Field emergence of Tabasco pepper (Capsicum frutescens L.) often requires 10 to 14 days even under optimum conditions. Methods to increase and accelerate Tabasco seed germination were investigated. Seed were extracted from orange and red fruit harvested at 150, 195, and 240 days from transplanting. The influence of fruit maturity on seed germination performance was significant over all harvest times. Seed extracted from red fruit had a significantly greater germination rate and final germination percentage than seed from orange fruit. Germination performance of seed extracted from red fruit harvested 150 days after transplanting was superior to that of seed harvested from orange fruit and to seed harvested later in the growing season. Results indicate that Tabasco seed extracted from red fruit responds favorably to a period of dry after ripening. A 21-day period at 25°C appears to be optimum for improving germination percentage and rate.
Pathogen free seed has long played a critical role in reducing or eliminating the severity of various diseases in commercial fields. The California Crop Improvement Association (CCIA) provides quality assurance services to the seed industry that are designed to promote the production, distribution and use of high quality seedstocks for agricultural production. To that end, CCIA has developed a Disease Inspection Program to assist vegetable seed producers in eliminating the bacterium, Acidovorax avenae subsp. citrulli (AAC), from cucurbit (Cucurbitaceae) seedstocks. This program utilizes recommendations and standards beginning at parent seed production of hybrids through the production of commercial seedlots. Training of field personnel, field inspections and tissue tests, followed by growouts of at least 30,000 seedlings are used as components of this quality assurance program.
Wildflower species are being used for highway median vegetation, land restoration programs, and revegetation of industrial sites. Rapid, uniform germination is critical to establishment of new stands Seed priming techniques may increase the potential for successful establishment under adverse environmental conditions. The influence of seed priming of Gaillardia puchella, Monarda citriodora, and Coreopsis tinctoria on germination at 10° and 25° C was investigated. Seeds of the three species were placed in five levels of oxygenated KNO3 (3.5, 3.25, 3.0, 2.75, and 2.5%) solutions, or a control of oxygenated distilled water for 144 hr. Germination percentage and rate of germination (MRG) were improved for Gaillardia and Coreopsis at 10° and 25°C. Germination percentage and MRG for Monarda were not effected by priming at 25°C, but both were significantly improved at 10°C, The optimum concentration of KNO3 for greatest rapid germination was dependent on the seed variety, These results suggest that in most cases wildflower germination percentage and rates ware improved by the priming procedure.