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  • Author or Editor: J.H. Murphy x
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The fine fescues are generally considered to be acid-tolerant compared to many other cool-season turfgrasses. However, there is a lack of documentation on aluminum tolerance of fine fescues at both the species and cultivar levels. A total of 58 genotypes belonging to five species or sub-species were screened under greenhouse conditions using solution culture, sand culture, and acid Tatum subsoil. This soil had 69% exchangeable Al and a pH of 4.4. An Al concentration of 640 μM and a pH 4.0 were used in solution screening and sand screening. Differences in Al tolerance were identified at both species and cultivar levels based on relative growth. The genotypes with endophyte infection generally exhibited greater Al tolerance than endophyte-free genotypes. The results indicate that fine fescues vary in Al tolerance and there is potential to improve Al tolerance with breeding and to refine management recommendations for fine fescues regarding soil pH.

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Early weed infestation in vegetable crops reduces both early and total marketable yield and quality. Even if escape weeds (12 inches tall or larger) are later killed by a postemergence herbicide application, their skeletons can cause yield loss due to competition for light, temperature modification within the plant canopy, and interference with fungicide and insecticide applications. In addition, weeds can also serve as a reservoir for insect and disease organisms, especially viruses. Experiments in nonchemical weed control in cabbage were conducted at the Horticulture Research Farm, Russell E. Larson Research Center, Rock Springs, Pa., from 1993 to 1995. In addition to weedy and hoed check plots, flaming weeds at 2- to 4-leaf stage of growth with propane gas burners and planting annual ryegrass (Lolium multiflorum) between the rows of cabbage, living mulch, were evaluated during 3 years. The cabbage cultivar Rio Verde was transplanted generally between 15 June and July during each year. Both flaming and living mulch treatments produced yield and head quality similar to the hoed check. Management and timing of ryegrass planting in relation to cabbage establishment is very critical for success with living mulch. Flaming requires straight rows of cabbage or other crop, tractor with driver that can maintain a straight line, and burners that are aligned to burn weeds and not the crop. Results will be discussed.

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Botanical gardens have extensive spatial databases of their plant specimens; however, the fungi occurring in them are generally unstudied. Botanical gardens, with their great plant diversity, undoubtedly harbor a wide range of symbiotic fungi, including those that are plant-pathogenic. One such group of fungi is powdery mildews (Erysiphaceae). The powdery mildews are among the most prevalent and economically important plant pathogens in the world, with an estimated 906 species in 19 genera. They are known to infect more than 10,000 species of flowering plants and although some species occur across a range of hosts, many are associated with specific plants. Powdery mildews have undergone a long and dynamic coevolution with their host plants, resulting in co-speciation. Botanical gardens provide a living laboratory in which to study these fungi, leading to a wealth of undiscovered fungal diversity. Furthermore, monitoring pathogens in botanical gardens has led to important ecological findings related to the plant sciences and plant protection. Between 2018 and 2022, a collaborative citizen science project was established with 10 botanical gardens in the United States and Mexico. A total of more than 300 powdery mildew specimens were collected on 220 different host taxa. We sequenced the entire internal transcribed spacer (ITS) and large subunit (LSU) rDNA loci and phylogenetically and morphologically analyzed these collections revealing 130 species, of which 31 are likely unknown to science. This research highlights the importance of botanical gardens as a reservoir of fungal diversity. Future research will further elucidate the coevolutionary relationship between powdery mildews and their hosts and extend the current study to evaluate other plant pathogens and fungi in botanical gardens.

Open Access