Infection of the Native California Grass, Bromus carinatus, by Fusarium circinatum, the Cause of Pitch Canker in Pines

At Point Reyes National Seashore in California, Fusarium circinatum, the causal agent of pitch canker in pines, was isolated from Pinus muricata, the California native grass, Bromus carinatus, and the introduced grass, Holcus lanatus. All grass plants from which F. circinatum was isolated were symptomless. Pathogenicity of grass isolates was confirmed by inoculation of P. radiata trees, which developed symptoms similar to trees inoculated with a pine isolate of F. circinatum. Isolates from grasses were somatically compatible with isolates recovered from symptomatic pines. B. carinatus grown in a growth chamber was inoculated with a green fluorescent protein-expressing strain of F. circinatum. Segments of inoculated leaves were incubated in moist chambers; after 1 to 2 days, sporulating hyphae were observed growing from leaf tissue. Spores of F. circinatum removed from B. carinatus leaves were confirmed to be fluorescent when illuminated with ultraviolet light. These results raise the possibility that B. carinatus cryptically infected by F. circinatum may be a source of propagules capable of infecting pines.

Changes in Forage Quantity and Quality With Continued Late-Summer Cattle Grazing a Riparian Pasture in Eastern Oregon of United States

A pasture (45 ha) in northeastern Oregon was grazed with 30 yearlings (419 kg, Body Condition Score [BCS] = 5.05) and 30 mature cows with calves (499 kg, BCS = 4.65) during August of 2001 and 2002. Sampling dates were d 0, d 10, d 20, and d 30. Forage availability before grazing was 1,039.0 kg·ha^-1 and declined to 332.6 kg·ha^-1 after grazing (<em>p </em>&lt; 0.10). Grasses dominated the pasture (44.5%), followed by forbs (30.7%), grasslikes (15.9%), and shrubs (8.9%). Due to grazing quackgrass (<em>Agropyron repens </em>(L.) Beauv.), western fescue (<em>Festuca occidentalis </em>Walt.), California brome (<em>Bromus carinatus </em>Hook.), and redtop (<em>Agrostis alba </em>L.) exhibited the greatest decline in quantity. Shrub utilization was high from d 20 to d 30 (49 to 58% for willow [<em>Salix rigida</em> {Hook.} Cronq.]<strong> </strong>and 58 to 74 % for alder [<em>Alnus incana </em>{L.} Moench.]). Forbs decreased (<em>p</em> &lt; 0.10) in moisture late in the grazing period, while shrubs were (<em>p</em> &gt; 0.10) still succulent (63%). Forbs and shrubs were higher (<em>p</em> &lt; 0.10) than grasses in crude protein (11, 14, and 6%, respectively) and digestibility (59, 50, and 42%, respectively). In summary, our results suggest that cattle grazing late-summer riparian pastures will switch to intensive shrub utilization when grasses decline in quantity and quality, and forbs decline in quantity. Land managers need to know the effect of their management on vegetation and if a goal is to protect riparian woody vegetation, our data suggest that late-summer grazing should be light, or avoided when grasses have senesced.

Verification of the systematic position of California brome (Bromus carinatus Hook. and Arn., Poaceae), cv. 'Broma', on the basis of analysis of issr markers

‘Broma’ is a grass cultivar belonging to the species <em>Bromus carinatus</em>. In the Lists of Agricultural Plant Varieties of the Research Centre for Cultivar Testing (COBORU), it is shown as <em>Bromus willdenowii </em>(= <em>B. catharticus</em>, <em>B. unioloides</em>) (List of Agricultural Plant Varieties 1989-2009), whereas already in 1984 Mirek demonstrated on the basis of morphological analysis that this was a different closely related species – <em>B. carinatus</em>. <br /> The aim of the present study was to verify the species affiliation of cv. ‘Broma’. The conducted analysis of ISSR molecular markers included representatives of cv. ‘Broma” as well as of <em>B. carinatus </em>and <em>B. willdenowii</em>. <br />The method used allowed the identification of molecular markers of the above-mentioned taxa. The numerical analysis of the obtained results suggests that cv. ‘Broma’ should be classified in the species <em>B. carinatus</em>, not <em>B. willdenowii</em>.

Mapping genetic variation and seed zones for Bromus carinatus in the Blue Mountains of eastern Oregon, USAIn this article, mention of companies or trade names does not constitute an endorsement of any product or procedure.

Seed transfer zones ensure that germplasm selected for restoration is suitable and sustainable in diverse environments. In this study, seed zones were developed for mountain brome ( Bromus carinatus Hook. & Arn.) in the Blue Mountains of northeastern Oregon and adjoining Washington. Plants from 148 Blue Mountain seed source locations were evaluated in common-garden studies at two contrasting test sites. Data on phenology, morphology, and production were collected over two growing seasons. Plant traits varied significantly and were frequently correlated with annual precipitation and annual maximum temperature at seed source locations (P < 0.05). Plants from warmer locations generally had higher dry matter production, longer leaves, wider crowns, denser foliage, and greater plant height than those from cooler locations. Regression models of environmental variables with the first two principal components (PC 1 and PC 2) explained 46% and 40% of the total variation, respectively. Maps of PC 1 and PC 2 generally corresponded to elevation, temperature, and precipitation gradients. The regression models developed from PC 1 and PC 2 and environmental variables were used to map seed transfer zones. These maps will be useful in selecting mountain brome seed sources for habitat restoration in the Blue Mountains.

Seed yield of three Bromus species native to western Canada

There is an increasing demand to use native grass species for revegetating disturbed sites such as logged clearcuts. The value of such species is closely linked with their ability to produce seed. We compared seed yield of three native Bromus species (Bromus carinatus Hook. & Arn., B. ciliatus L., and B. anomalus Rupr. Ex Fourn.) and three domestic forage species (B. riparius Rehm., B. inermis Leyss., and Dactylis glomerata L.) and tested the hypothesis that native species divert fewer resources to reproductive growth than do domestic grasses. Six experiments were conducted at five locations in western Canada to evaluate the potential for seed yield from native brome. Bromus carinatus seeds ripened, on average, the first week of August, similar to B. riparius and D. glomerata, while seed of B. anomalus and B. ciliatus ripened about the third week of August, similar to B. inermis. Seed yields were highly variable among sites and between years. Over all sites, yields among species were not significantly different (P = 0.05). Mean second-year yield was less than half of that of the first harvest year. Yields of 2–3 t ha−1 were found for B. anomalus, B. ciliatus and B. inermis at certain sites. Seed yields were positively correlated to inflorescence number m−2 in both harvest years and to harvest index in the first harvest year. Based on seed yields that were similar to B. inermis in this study, it should be possible to produce sufficient quantities of reasonably priced seed of native Bromus species for the revegetation industry. Key words: Smooth bromegrass, meadow bromegrass, orchard grass, Bromus sp., Dactylis glomerata

Growth and forage quality of three Bromus species native to western Canada

There is growing interest in revegetating disturbed areas with native plant species; thus seed sources for appropriate native species need to be developed. In this study, we compared growth and forage quality of three native Bromus species (Bromus carinatus, B. ciliatus, and B. anomalus) collected in central Alberta with growth and forage quality of three domestic forage species (B. riparius Rehm., B. inermis Leyss., and Dactylis glomerata L.). Eight establishment year-locations were used for experiments conducted between 1993 and and 1996 at six locations in western Canada. Seedling establishment measured in 4 year-locations indicated that all native Bromus species established as well as the domestic bromegrasses, and that B. carinatus exceeded seedling establishment of the domestic bromegrasses. Bromus carinatus either yielded the same or less dry matter (DM) that the domestic bromegrasses, the same or more than D. glomerata, and more than B. ciliatus or B. anomalus. Bromus carinatus was either as tall as or shorter than the domestic bromegrasses, as tall as D. glomerata, and taller than Bromus ciliatus and B. anomalus. Bromus carinatus was more prone to lodging than B. ciliatus, B. anomalus, or the domestic species. These native Bromus species appear to have the required establishment potential and productivity to be suitable for reseeding disturbed areas and fill the niche where native species are required. Key words: Bromus, dry matter, crude protein, dry matter digestibility, acid detergent fibre, smooth bromegrass, meadow bromegrass