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  • Author or Editor: L.L. Davis x
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Public interest in installing landscapes for reduced maintenance remains high. While availability and specification of native and/or adapted landscape plants such as wildflowers and prairie grasses increase, establishment, management, and expectations of such plantings are not well understood. Our objectives in this study were to measure temporal changes of mixed prairie wildflower plantings under various management regimes and to determine consumer expectations and preferences in these plantings. Nine combinations of wildflowers and prairie grasses were planted in June 1997 at the John Seaton Anderson Turfgrass and Ornamental Research Area, Univ. of Nebraska Agricultural Research Development Center near Mead. On-site surveys were conducted during the Festival of Color, a popular outreach event that occurs annually in September at the site. In 1997 and 1998, the festival attracted more than 9000 and 10,500 participants, respectively, of which 750 completed the survey. To determine preferences for planting compositions, plot desirability ratios were calculated from scaled responses. In 1997, respondents preferred the planting composed of only annuals by a ratio of 5.8: 1 (rated desirable vs. undesirable). This result changed dramatically by the second year, in which the desirability ratio for annuals was 0.3: 1, while that of the combination of perennials and annuals was 11.2: 1. Our plant population density and flowering data validate consumers' preference for abundant color. In late summer of the establishment year (1997), the percentage of the plant population in full bloom was highest in the planting of annuals alone as expected and in 1998 was lowest in the annuals.

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In his State of the Union Address (1990), President Bush proposed planting a billion trees annually for the next 10 years. Organizations such as Global ReLeaf are planning to plant 400 to 600 million trees by the year 2000. A review of science education periodicals and general information available on tree planting and care reveal little directed to children. Science education tends to focus on the nature, not the handling of trees, and where planting ideas are suggested, they tend to be about growing trees from seed. To determine the level of landscape tree care knowledge of 4th–6th graders, a questionnaire addressing how trees grow, site and tree selection, proper planting, and other areas was administered by 4-H agents and Univ. of Florida students throughout the state during five camps, involving 211 children during the summer of 1995. The questionnaire was revised with additional topics such as irrigation and mulching added and administered during three 4-H camps involving 77 4th–6th graders. Answers to these questionnaires were used to develop materials targeted for this age group and their teachers.

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Abstract

Evaluations of cooked fresh beans showed that the persistent-green color (PC) cv., Custer, was darker, greener, and less yellow than the normal-green cv., Canyon. Persistent-green color lines Xlda 71-2081 and Xlda 267-4 were intermediate between the 2. Chlorophyll concentrations were higher in all PC lines than in the normal-green cultivar but the ratio of chlorophyll a/b was lower. Chlorophyll content was significantly correlated with Gardner color values and with visual color scores. No color values correlated with pheophytin or carotene content.

Xlda 71-2081 had the highest work-to-shear values, % seed, % fiber, and highest panel scores for fibrousness. Whether the higher values were attributable to genetic controls or to a difference in maturity was not determined in this study. Little sloughing was observed. All cultivars had a slightly to moderately full, natural flavor. The PC beans were equal or superior to the normal-green cultivar in all measured quality characteristics with ‘Custer’ showing the most promise.

Open Access

Osmoconditioning was examined as a presowing seed treatment for its influence on germination, rate of germination, and initial seedling root growth in seeds of A morpha fruticosa L. (imbibed for 48 hrs) and Hippophae rhamnoides L. (imbibed for 18 hrs) at 25C. Based on preliminary studies, seeds were imbibed in one of five osmotic solutions (0, -0.2, -0.7, -1.5, or -3.0 MPa) prepared with polyethylene glycol-8000. Seeds were then sown in test tubes containing plugs of Oasis growing medium saturated with osmotic solutions of no drought (0 MPa) or drought (-1.0 MPa) conditions at 15-35C. Root growth was measured with an image analysis system. Total root growth per seedling was less for both species in drought conditions regardless of temperature. Presowing treatments did not produce large differences in germination or rate of germination in either species.

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Diminishing milkweed (Asclepias sp.) populations are contributing to the conspicuous decline of the iconic monarch butterfly (Danaus plexippus). This research sought to improve milkweed propagation success, a core component of summer habitat restoration projects. Specifically, this research assessed the effects of container volume and fertilizer application rate on growth and first year field survival of two species of milkweed common to western North America, namely showy milkweed (A. speciosa) and narrowleaf milkweed (A. fascicularis). Generally, larger roots and shoots developed when plants were given the high rate of fertilizer (6.5 g·L−1) and when reared in the largest containers (2600 mL). For narrowleaf milkweed, nearly all plants developed a firm plug (i.e., one in which the root system remained intact when removed from the container) after 22 weeks. Most narrowleaf milkweed plants flowered 15 weeks after sowing when grown in the largest container with either the low (2.7 g·L−1) or high fertilizer rate or the midsized container (444 mL) with a high rate of fertilizer. For showy milkweed, a firm plug developed for nearly all individuals by the end of the growing season only when given the high fertilizer rate. None of the showy milkweed plants developed an inflorescence by 15 weeks. Results of this research improve our understanding of milkweed propagation and will aid in the efforts to restore the monarch butterfly’s summer breeding habitat by providing propagation protocols across a range of stocktypes.

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Abstract

AS9 is a sugary-1 breeding population of sweet com (Zea mays L.) having moderate to high resistance to first brood attack (leaf feeding phase) by the European corn borer (Ostrinianubilalis, Hübner). The first sugary-1 source material having such resistance, it has been composited from diverse sources and is being released for its potential value in sweet corn breeding.

Open Access

Abstract

A gas chromatographic method for the determination of alcohol in citrus juice by analysis of headspace is described. The volume of juice is not critical, but the bath temperature for samples must be constant. Juice samples should be analyzed as soon as possible, or kept refrigerated to avoid alcohol production by contaminating organisms.

Open Access

Abstract

Procedures for forced field infestation of maize with European corn borer egg masses, placed to simulate possible natural ovipositional sites and to emphasize damage to the ear, were compared. A growth chamber procedure using excised ears and a free-choice (preference) infestation procedure were also used. Forced infestation in the field permitted infestation at a uniform relative maturity and uniform development of borers from time of infestation to evaluation. An ear-and-leaf infestation procedure appeared to be the most appropriate for simultaneous evaluation of kernel damage and stalk tunneling. Estimated heritabilities, using this procedure on 2 segregating populations, were 0.71 and 0.84 for kernel damage and 0.39 and 0.79 for stalk tunneling. Phenotypic correlations among 3 ear damage criteria were noted (r = 0.42 to 0.46). Evaluation based on kernel damage alone, excluding cob tunneling and number of surviving larvae, was considered sufficient. There was no evidence that kernel damage was influenced by level of stalk tunneling.

Open Access

Abstract

Sugars in watermelon [Citrullus lanatus (Thunb.) Matsum. & Nakai] cultivars grown at Leesburg, Florida, were determined by liquid chromatography in 1976, 1977, and 1979. There was a wide variation among cultivars in the ratio of total reducing sugars, fructose plus glucose, to the nonreducing sugar, sucrose. This ratio was dependent upon cultivar and stage of maturity. In 1979, sugars in developing fruit of 8 watermelon cultivars were determined at 7 intervals from 12 to 36 days after anthesis. Initial development of sugar was more rapid in the cultivars ‘Sugarlee’, ‘Crimson Sweet’, ‘Dixielee’, and ‘Yellow Baby’ than in ‘Charleston Gray’ and ‘Jubilee’. Early development of sugar is especially important for production of high quality fruit when melons are harvested before full maturity for the commercial trade. In general, fructose and glucose increased until the 24th day and declined thereafter, whereas sucrose was not detected until the 20th day and increased thereafter. The relative sweetness at all stages was calculated.

Open Access

Abstract

Artificial was compared to natural infestation for evaluating kernel damage and stalk tunneling on maize (Zea mays, L.) caused by European corn borer (Ostrinia nubilalis, Hiibner) larvae. Under conditions of natural infestation, differential damage levels among families were more closely correlated with silk date than oviposition frequencies on the host plants. The association between damage and silk date was reduced following artificial infestation. Artificial infestation, which permits infestation at a common stage of maturity (full silk), a uniform and greater insect population on host plants, and a uniform opportunity for larval development on the ear from time of infestation to time of evaluation, is preferred for differentiating maize genotypes for borer resistance.

Open Access