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An elite group of 38 strawberry accessions representing all subspecies of the beach strawberry [Fragaria chiloensis (L.) Miller] and the scarlet strawberry (F. virginiana Miller) was planted in a replicated design at five locations across the United States, and evaluated for plant vigor, flowering date, runner density, fruit set, fruit appearance, and foliar disease resistance. Considerable genotyp× location interaction was observed for many of these traits. However, a few genotypes were impressive at all locations including PI 551735 (FRA 368) with its unusually large, early fruit, and PIs 612486 (NC 95-19-1), 612493 (Frederick 9), and 612499 (RH 30), which were very vigorous and had unusually good fruit color. Genotypes that were superior at individual locations included PIs 551527 (FRA 110) and 551728 (Pigeon Pt.) in Maryland for their large fruit, and PI 612490 (Scotts Creek) in Oregon which had extremely large fruit, superior color, firmness, and flavor. The PIs 612495 (LH 50-4), 612498 (RH 23), and 612499 (RH 30) performed well as day neutrals at multiple sites.

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Abstract

Seedlings of Baptisia australis (L.) R. Br. and Liatris aspera Michx., grown in prairie soil with no additional P, benefited significantly from inoculation with Glomus etunicatum Becker and Gerd., regardless of whether they were adequately watered or moderately or severely drought-stressed. In the presence of additional P, growth of severely droughted inoculated seedlings for both plant species was not significantly greater than noninoculated plants. When the influence of four Glomus species on growth of the two forbs was compared under drought-stress conditions with no supplemental P, growth of both plant species was signficantly improved by all fungal species compared to noninoculated controls. Preinoculated seedlings of both plant species were transplanted into disturbed-site soils with indigenous vesicular-arbuscular mycorrhizal (VAM) fungi present and subjected to severe moisture stress. After 12 weeks, inoculated seedlings were significantly larger than noninoculated seedlings for all soil types, with or without additional fertilizer (0.15 kg P/m3 + 0.075 kg N/m3). Under conditions of drought stress and low fertility, preinoculated seedlings of both B. australis and L. aspera grew significantly larger than noninoculated seedlings.

Open Access

Abstract

Seedlings of blue wildindigo [Baptisia australis (L.) R. Br.], rough gayfeather (Liatris aspera Michx.), and butterfly milkweed (Asclepias tuberosa L.) were grown in either a 1 soil : 1 sphagnum peat : 1 perlite (by volume) or 1 soil : 1 sand medium (v/v), amended with 0.00, 0.29, or 0.58 kg P/m3, and inoculated with Glomus etunicatum Becker and Gerd., G. fasciculatum (Thax. sensu Gerd.) Gerd. and Trappe, G. macrocarpum Tul. and Tul., G. mosseae (Nicol. and Gerd.) Gerd. and Trappe, or remained noninoculated. The objective was to determine whether vesicular-arbuscular mycorrhizal (VAM) fungi can establish and enhance plant growth, and how this would be affected by soil amendments. Replications were transplanted into the field to determine whether VAM pretransplant inoculation increased host growth and flowering. In the greenhouse, total dry weight of the three wildflower species grown in 1 soil : 1 sand (v/v) medium with no P was significantly improved by addition of most mycorrhizal species tested, but the response varied among plant species. At 0.29 kg P/m3, fewer mycorrhizal growth responses were evident. No growth responses were evident at 0.58 kg P/m3. B. australis was the only species that benefited from mycorrhizal inoculation in the 1 soil: 1 sphagnum peat: 1 perlite (by volume) medium at 0.00 and 0.29 kg P/m3. There were no differences in tissue P content within the three species when VAM-inoculated plants at 0.00 kg P/m3 were compared to noninoculated controls. At 0.29 kg P/m3 in the 1 soil : 1 sand medium, inoculated seedling tissue P increased, but in the 1 soil : 1 sphagnum peat : 1 perlite medium, noninoculated controls had significantly higher tissue P contents compared to inoculated seedlings. In the field, height and inflorescences per plant for the wildflowers were improved by VAM inoculation during the 2nd growing season.

Open Access

The ongoing drought in the Intermountain West has brought a great deal of attention to water conservation over the past several years. During that time, turfgrass irrigation has been targeted as a source for large potential water savings. Some communities promote downsizing turfgrass areas as the best water conservation measure. In reality, turfgrass controls erosion, reduces evaporation from a site, and provides a safe surface for human activities. One alternative to elimination would be wider use of low water-use-grasses appropriate to the area. However, many questions arise regarding the choice of such grasses and their management. Our research addresses these questions. Plots have been established at Montana State University, Bozeman; Utah State University, Logan; and USDA-NRCS Plant Materials Center, Bridger, Mo. The grasses considered include 12 single species and 12 mixed species stands of `Cody' buffalograss, `Foothills' Canada bluegrass, `Bad River' blue grama, sheep fescue, sandberg bluegrass, muttongrass, and wheatgrasses `Sodar' streambank, `Road Crest' crested, `Rosana' western, and `Critana' thickspike with Kentucky bluegrass and tall fescue as controls. Line source irrigation allowed the plots to be evaluated at a number of levels of irrigation. Experimental measurements on the plots included growth response as determined by clipping yield and quality ratings, and species composition. Fescues and wheatgrasses retained their color, texture, and density throughout the growing season, regardless of moisture level. Warm-season grasses performed well in June, July, and August only, and worked poorly in mixtures as the green cool-season grasses could not mask the brown dormant leaves in cooler weather.

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The total anthocyanin and total phenolic content of wild (samples from 4 populations) and cultivated (samples from 32 populations) Pacific Northwestern American Vaccinium species (V. membranaceum, V. ovalifolium, and V. deliciosum) were evaluated. The total monomeric anthocyanin content of all huckleberry samples analyzed ranged from 101 to 400 mg/100 g (expressed as cyanidin-3-glucoside), and the total phenolics varied from 367 to 1286 mg/100 g (expressed as gallic acid). Cluster analysis separated the samples into four different groups based on their anthocyanin and total phenolic content. Two groups had greater anthocyanin pigment and total phenolics; one consisted entirely of cultivated V. ovalifolium (LIG10, VAC485, VAC487, LIG33, LIG9, LIG2, and VAC349) and the other consisted of just cultivated V. membranaceum (LIG25). Significant variations in total anthocyanins, total phenolics, and the ratio of the total anthocyanins and total phenolics were observed among the different V. membranaceum, V. ovalifolium, and V. deliciosum populations cultivated in the Willamette Valley, Ore. The profile of the individual anthocyanins of the wild V. membranaceum, wild V. ovalifolium, and V. corymbosum `Rubel' were conducted by high-performance liquid chromatography. The chromatograms of V. membranaceum, V. ovalifolium, and `Rubel' were distinctly different in the amounts of delphinidin, cyanidin, and malvidin glycosides.

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A common complaint with day-neutral strawberries is that they perform poorly in mid-summer heat. Since most modern day-neutral cultivars are derived from the same Fragaria virginiana ssp. glauca clone from Utah, we felt it prudent to search for alternate sources of day-neutrality that were more heat-tolerant. We compared the sexual and vegetative performance of nine F. virginiana clones from a wide range of environments including the Utah site, and four F. × ananassa day-neutral types (`Aromas', `Fort Laramie', `Ogallala', and `Tribute') under constant temperatures of 18, 22, 26, and 30 °C and 12-h days. `Aromas' and `Tribute' carry the Utah source of day-neutrality, while `Fort Laramie' and `Ogallala' are old cultivars that have a different, complex background. After a 4-week period of acclimation, we counted the number of crowns, inflorescences, flowers, stolons, and daughter plants that emerged over a 10-week period, and measured the dry weights of component parts. ANOVA tables revealed that temperature regime (T), genotypes (G), and T*G were significant for flower number (FLN) and total dry matter accumulation, while species and T*G were significant for daughter plant number (DPN). Mean FLNs across the four temperatures were 6.8, 3.7, 3.3, and 1.2, while mean DPNs were 0.7, 0.9, 0.7, and 1.8. F. virginiana clones averaged 3.8 FLNs and 1.8 DPNs, while the F. × ananassa clones averaged 4.1 FLNs and 0.2 DPNs. There was generally more variability among the F. virginiana clones than the F. × ananassa clones, but the F. × ananassa cultivars, `Fort Laramie' and `Ogallala', performed best at 30 °C. The Wasatch clone did not flower in any treatment, suggesting it is not day-neutral.

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