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  • Author or Editor: M.W. Adams x
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Abstract

Rapid clonal multiplication of Cephalotus follicularis Labill. was achieved on 1/2 strength Linsmaier-Skoog medium with 30 g/liter sucrose and 8 g/liter agar. Shoot tip cultures were started on a medium supplemented with 0.1 mg/iiter indolebutyric acid (IBA) and 1.0 mg/liter benzyl adenine (BA), which best stimulated growth, and kept in darkness the first 6 weeks. After 2 more months in constant light they were subcultured to a medium with 0.1 mg/liter naphtahaleneacetic acid (NAA) and 0.1 mg/liter BA that induced rapid proliferation. A 5-10 fold increase in plant material was achieved after each subculture.

Open Access

The experiment was conducted at the Cunningham Research Station in Kinston, N.C. (coordinates: N35 18.372; W77 34.937), on Goldsboro loamy sand. Three cultural systems (bare ground + overhead irrigation bare ground + drip irrigation, black plastic + drip irrigation) and seven fungicide treatments were evaluated in a split-plot design with cultural system as the main plot and fungicide treatments as subplots. The cultivar used was `Mickey Lee'. The trial was installed 18 July. Soil moisture was monitored in each of the cultural regimes using soil moisture sensors (Spectrum Technologies, Inc, Plainfield, IL) and rain gauges. The cultural systems using drip irrigation were irrigated to 10 cb starting when soil moisture reached 40 cb. Overhead irrigation was used to maintain at least 2 inches per week total precipitation beginning 12 Aug. Cultural systems and fungicide treatments were replicated 4 times. To prevent gummy stem blight and powdery mildew, Pristine (14.5 oz/acre) and Quintec (6 oz/acre) were alternated with Bravo Weather Stik (2 pt/acre) and Flint (4 oz/acre) on a 7-day interval, beginning 16 Aug. Experimental fungicide treatments were applied using a CO2 backpack sprayer equipped with a 3-nozzle (19-inch spacing) handheld boom with hollow cone nozzles (TXVS-26) delivering 40 gal/acre at 45 psi. Treatments were initiated when the largest fruit were about 6 inches in diameter. All treatments were applied on a 7-day interval with applications on 25 Aug. and 2, 9, 16, and 23 Sept. Plots were inoculated on 12 and 19 Sept. by hand-scattering 0.5 lb of 1-cm cubes of naturally P. capcisi-infected acorn squash fruit per plot. Disease severity was evaluated on 26 Sept. as fruit rot incidence and percent foliar necrosis. Captan was most effective in suppressing fruit rot regardless of cultural regime. Captan and NOA-446510 were both effective in reducing vine collapse across all cultural regimes. Incidence of fruit decay was significantly greater in the bare ground + overhead irrigation (overhead) cultural regime while plasticulture (plastic) and bare ground + drip irrigation (drip) resulted in similar levels of fruit decay and vine collapse. No interaction of cultural regime with treatment was detected. Watermelon stems and foliage are typically very resistant to Phytophthora blight, but significant vine collapse occurred in many plots. P. capsici was consistently isolated from diseased foliage and stems and is considered the primary cause of vine collapse.

Free access

Abstract

In each of 2 cultivars of dry bean, populations of fruits having either low or high abscission potentials were established by removing early opening flowers from half the plants and leaving all flowers on the remainder. Fruits were harvested 4 to 5 days after anthesis and separated according to length, which was negatively correlated with abscission potential. Abscisic acid (ABA), phaseic acid (PA), and dihydrophaseic acid (DPA) contents were determined in methanol extracts of both pods and pedicels, using electron capture gas liquid chromatography. The content of these 3 compounds in pedicels was not significantly affected by cultivar, fruit size or flower removal. ABA content of pods was positively correlated with fruit load but was not related to fruit size. Phaseic acid content increased with fruit size and with fruit load but was not affected by cultivar. Content of DPA was unaffected by pod size or fruit load. We conclude that levels of extractable ABA, PA, and DPA do not regulate fruit abscission in dry bean.

Open Access

Abstract

Five cultivars and one breeding line of field bean (Phaseolus vulgaris L.) were evaluated for their differential reactions to beta, gamma, and delta races of anthraenose (Collectotrichum lindemuthianum [Sacc. and Magn.] Scrib.). Parental, F1 and F2 plants from 10 crosses involving anthraenose resistant and susceptible parents were inoculated with the 3 races. Inoculated plants were maintained in a mist chamber for 8 to 10 days until plants could be classified into resistant and susceptible groups on the basis of their reactions to the pathogen. The F2 segregation patterns suggested that independent and complementary gene action at 1 or 2 different loci produced a resistant reaction to all races of the pathogen. In addition, an allelomorphic series of three alleles was assumed to be controlling resistance to the beta race. A breeding scheme, involving alternate generations of back-crossing to the recurrent parent and selfing is an effective method to develop resistant cultivars.

Open Access

Abstract

A study was conducted to investigate the extent of genetic variations and the interrelationships of several quality traits of cultivars of navy and pinto bean (Phaseolus vulgaris L.) grown at 3 locations in Michigan. The measured traits were seed weight, initial weight of solids, surface color of dry and processed beans (L, aL, bL), weight of soaked beans, hydration ratio, clumps, splits, texture, washed and drained weight, and processed bean moisture. Significant cultivar differences were observed for most of the traits in both classes of beans. Location effects were highly significant for all traits. Certain traits showed significant cultivar × location interactions. Phenotypic correlation coefficients among pairs of characters indicated that, with few exceptions, there were low assocations among quality characters. Principal component analysis confirmed the independence of traits. A selection strategy based on a tandem selection procedure followed by construction of selection indices was suggested.

Open Access

Abstract

Rapid clonal multiplication of Pinguicula moranensis H.B.K., an “orchid-flowered” butterwort, was achieved on 1/5-strength Linsmaier-Skoog medium with 30 g/liter sucrose, pH 6.5, 6 g/liter agar, 0.02 mg/liter 6-benzylamino purine (BA), and 0.01-0.10 mg/liter naphthaleneacetic acid (NAA).

Open Access

Abstract

A computer system consisting of several programs and files, developed for management of information generated in all phases of a dry, edible bean (Phaseolus vulgaris L.) breeding program, is described. The interactive system both produces field books and prints labels for field stakes and planting and harvesting bags.

Open Access