Search Results

You are looking at 1 - 10 of 11 items for

  • Author or Editor: M.J. Silbernagel x
Clear All Modify Search

Abstract

The ARS/USDA and the Agricultural Experiment Station of Washington State Univ. announce the release of germplasm line, FR (Fusarium Resistant)-266, a bush snap bean (Phaseolus vulgaris L.) line, which is resistant to Fusarium root rot caused by Fusarium solani (Mart.) Appel & Wr. f. sp phaseoli Burkh. Snyd. & Hans. FR-266 also is resistant to bean common mosaic virus (dominant I gene)(l), curly top virus, and is tolerant to white mold caused by Sclerotinia sclerotiorurn (Lib.) deBary. FR-266 is the only known green-podded, white-seeded, bush snap bean line that has this unique combination of multiple disease resistance factors.

Open Access

Abstract

ARS/USDA and the Agricultural Experiment Station of Washington State Univ. announce the germplasm release of an Italian-style, flat-podded snap bean (Phaseolus vulgaris L.) line, VR (Virus Resistant)-Ro-mano, VR-Romano is unique in this class of snap beans because it is resistant to curly top virus and carries the dominant I gene resistance to bean common mosaic virus (1).

Open Access

Abstract

‘Blue Mountain’ snap bean (Phaseolus vulgaris L.) is a bush Blue Lake-type developed for commercial processing, home-garden, and market-garden use. It is resistant to Bean Common Mosaic Virus (BCMV), I gene, and Curly Top Virus (CTV), definite advantages in the seed production regions of the intermountain western states. ‘Blue Mountain’ is adapted to mechanical harvesting, and does well in either standard row widths or in high-density culture. Unlike many Blue Lake-types, ‘Blue Mountain’ picks clean (minimal leaves, stems, etc.) when mechanically harvested and its through-the-plant flow is comparable to ‘Tendercrop’. ‘Blue Mountain’ does well in the warmer dry climates found in the arid western states and in the mid-western and northeastern production areas. ‘Blue Mountain’ is not well-suited for production in the cool-cloudy Willamette Valley, where most of Oregon’s Blue Lake beans are grown. Plant and pod appearance resemble ‘Tendercrop’, but the processed pods have flavor, color, and quality that are comparable to ‘Blue Lake’. As a processing bean, ‘Blue Mountain’ is suitable for canning and freezing, cut or french-style pack. Its appearance and flavor will appeal to home and market gardeners.

Open Access

Abstract

Irrigation method and row spacing had a significant influence on the quality of fresh, canned, and frozen snap beans (Phaseolus vulgaris L.). Sprinkle irrigated fresh and canned snap beans contained more ascorbic acid than rill irrigated snap beans. Rill irrigated snap beans had more intense color, lower shear values, less turbid brine, and less drained weight loss. Canned snap beans grown in narrow rows had less drained weight loss than snap beans from wide rows. Frozen snap beans from narrow rows had more drip loss, less moisture, increased soluble solids, and increased ascorbic acid content than those from wide rows. Under the conditions of this study, rill irrigated snap beans and snap beans grown in narrow rows did have quality advantages over sprinkle irrigated snap beans and snap beans grown in wide rows.

Open Access

Abstract

A “seed index” based on the product of seed weight by length was positively correlated with the fiber development of large- and medium-sieved snap beans (Phaseolus vulgaris L.) whether fresh or canned. Fresh seed index values which are easier to measure than fiber, can be used to estimate canned product quality rapidly and inexpensively. It is suggested that cultivars be compared for yield, days and/or heat units to harvest maturity, sieve size distribution and quality when at least 95% of the harvested pods are within fancy Grade as determined by the seed index.

Open Access

Abstract

Viability of pollen grains of isogenic sibling bean (Phaseolus vulgaris L.) selections of known tolerance of sensitivity to high temperatures (HT), as previously determined by pod retention and seed yield, was compared to that of a common parent bean selection and a cowpea [Vigna unguiculata (L.) Walp.] cultivar. Exposure of newly opened flowers to temperatures of 35° or 41°C reduced the viability of pollen grains in all bean selections. Pollen of all sibling selections was less affected by HT than pollen of their common parent suggesting transgressive segregation of factors for HT tolerance. At 41°, most pollen grains were destroyed in the parent bean selection and the 2 HT-sensitive siblings, whereas 44% to 55% of the pollen grains appeared to be viable in the 2 HT-tolerant siblings. Pollen viability of the HT-tolerant cowpea cultivar was not reduced by temperatures to 41°. Pollen staining indicated an interrelationship between pollen viability and tolerance to HT stress among the bean selections. The technique described has the potential for rapid selection of HT-tolerant genotypes in hybrid populations.

Open Access

Blackleaf (a.k.a. chocolate leaf) is of worldwide concern in Vitis due to its negative impact on fruit ripening, yield reduction and overall stress on grapevines. Research suggests blackleaf is induced by high levels of UV radiation and overall light intensity, which induce color changes (purple-brown-black) in exposed leaves, resulting in >50% reduction in photosynthesis. The ability to detect blackleaf symptoms before expression can provide insight into metabolic stresses and the possibility of the use and/or timing of management practices to reduce its impact. Remotely sensed imagery and spatial analysis may elucidate reflectance-related processes and symptoms not apparent to the un-aided eye. In this research we mapped canopy growth (leaves/shoot and shoots/vine), metabolic triggers (photosynthesis, leaf water potential, soil moisture), and percent blackleaf expression within vineyards using global positioning system (GPS), infrared gas analyzer, and digital remotely-sensed images. Each image and data record was stored as an attribute associated with specific vine location within a geographical information system (GIS). Spatial maps were created from the GIS coverages to graphically present the progression of blackleaf across vineyards throughout the season. Analysis included summary statistics such as minimum, maximum, and variation of green reflectance, within a vineyard by image capture date. Additionally, geostatistics were used to model the degree of similarity between blackleaf values as a function of their spatial location. Continuing research will be aimed at identifying spectral characteristics of early season stresses due to UV light, water stress, and reduced photosynthetic capacity. Spatial relationships between early season stress and later blackleaf expression will be assessed using joint spatial dependence measures. Overall, information obtained through digital image and spatial analysis will supplement site level information for growers.

Free access

Research suggests that blackleaf (a leaf disorder in grape, Vitis labrusca L.) is induced by high levels of ultra violet (UV) radiation and overall light intensity, resulting in color changes (purple-brown-black) for sun-exposed leaves of the outer canopy, and a corresponding >50% reduction in photosynthesis. Metabolic indicators (photosynthesis and leaf water potential), percent blackleaf expression, and full spectrum leaf reflectance were mapped within vineyards using global positioning system (GPS) and digital remotely-sensed images. Each image and data record was stored as an attribute associated with a specific vine location within a geographical information system (GIS). Spatial maps were created from the GIS coverages to graphically present the progression of blackleaf across vineyards throughout the season. Analysis included summary statistics such as minimum, maximum, and variation of green reflectance, within a vineyard by image capture date. Additionally, geostatistics were used to model the degree of similarity between blackleaf values as a function of their spatial location. Remote-image analysis indicated a decrease in percent greenness of about 45% between July and August, which was related to a decrease in photosynthesis and an increase in blackleaf symptom expression within the canopy. Examination of full spectral leaf reflectance indicated differences at specific wavelengths for grape leaves exposed to UV or water-deficit stress. This work suggests that remote-image and leaf spectral reflectance analysis may be a strong tool for monitoring changes in metabolism associated with plant stress.

Free access

Abstract

Two bean cultivars and one breeding selection with different pod-retention characteristics were grown at mean soil moisture tension (MSMT) of 0.05 and 0.1 MPa in 2 separate plantings. In the 5 May planting, flower buds developed during the 1st 3½ weeks of flowering, were dated and counted, and those developing mature pods were identified. Sixty-five percent to 90% of all pods that reached full maturity were from floral buds that reached anthesis during the 1st 2 weeks of flowering. The percentage of pods reaching maturity varied among cultivars. About 40% of the floral buds that developed on the determinate bean selection were retained to full pod maturity. Only 20% to 25% of the floral buds developed on each of the indeterminate cultivars were retained to full pod maturity. An increase in the MSMT from 0.05 to 0.1 MPa in the 23 June planting reduced the number of pods and seeds/plant and total seed weight/plant by 20% to 40%, but the number of seeds/pod and weight/seed was not influenced by MSMT or by number of pods produced on either of the dry bean cultivars or the breeding selection.

Open Access