School of Plant and Environmental Sciences

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https://hdl.handle.net/10919/91436
SPES was formed in 2017 from three departments: Crop and Soil Environmental Sciences; Horticulture; and Plant Pathology, Physiology, and Weed Science.

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Browsing School of Plant and Environmental Sciences by Subject "0608 Zoology"

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    Meloidogyne aegracyperi n. sp. (Nematoda: Meloidogynidae), a root-knot nematode parasitizing yellow and purple nutsedge in New Mexico
    Eisenback, Jonathan D.; Holland, L. A.; Schroeder, Jill; Thomas, Steve H.; Beacham, Jacqueline M.; Hanson, S. F.; Paes-Takahashi, Vanessa; Vieira, Paulo (Society of Nematologists, 2019)
    Meloidogyne aegracyperi n. sp. is described from roots of purple nutsedge in southern New Mexico, USA. Mature females are small (310–460 μm), pearly white, with their egg masses completely contained inside root galls. The neck is often at a 90 to 130° angleto the protruding posterior end with the perineal pattern. The distance of the dorsal esophageal gland orifice (DGO) to the base of the stylet is relatively long (4.0–6.1 μm), and the excretory pore is level with the base of the stylet. The anterior portion of the rounded lumen lining of the metacorpus contains 3 to 10 small vesicles. The perineal pattern has a rounded dorsal arch with a tail terminal area that is smooth or marked with rope-like striae. Only two males were found. The body twists 90° throughout its length. The DGO to the base of the stylet is long (3.0–3.3) μm. The cephalic framework of the second-stage juvenile is weak, and the stylet is short (10.1–11.8 μm). The DGO to the base of the stylet is long (3–5 μm). The tail is very long (64–89 μm) and the hyaline portion of the tail is very narrow, making the tail finely pointed. Eggs are typical for the genus and vary in length (85.2–99.8 μm) and width (37.1–48.1 μm), having a L/W ratio of (2.1–2.6). Maximum likelihood phylogenetic analyses of the different molecular loci (partial 18S rRNA, D2-D3 of 28S rRNA, internal transcribed spacer (ITS) rRNA, cytochrome oxidase subunit II (COII)-16S rRNA of mitochondrial DNA gene fragments and partial Hsp90 gene) placed this nematode on an independent branch in between M. graminicola and M. naasi and a cluster of species containing M. chitwoodi. M. fallax, and M. minor. Greenhouse tests showed that yellow and purple nutsedge were the best hosts, but perennial ryegrass, wheat, bentgrass, and barley were also hosts.
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    Multi-scale habitat selection of key frugivores predicts large-seeded tree recruitment in tropical forest restoration
    Reid, J. Leighton; Zahawi, Rakan A.; Zarrate-Chary, Diego A.; Rosales, Juan A.; Holl, Karen D.; Kormann, Urs (Wiley, 2021-12-01)
    Large-seeded, animal-dispersed (LSAD) trees include some of the most valuable and threatened species in the tropics, but they are chronically underrepresented in regenerating forests. Toucans disperse many LSAD species, so attracting toucans to regenerating forests should help re-establish more diverse tree communities. We ask: (1) What constitutes suitable toucan habitat in premontane southern Costa Rica? (2) How much do small-scale restoration strategies influence toucan visitation compared to landscape-scale habitat suitability outside of restoration sites? (3) How well does toucan visitation predict the richness of LSAD tree species recruiting into regenerating forests? We combined habitat suitability models with long-term toucan observations and comprehensive tree recruitment surveys to assess these questions in a multi-site forest restoration experiment. Restoration treatments included tree plantations, natural regeneration, and applied nucleation. Habitat suitability obtained by modeling for three sympatric toucan species was predicted by elevation and the extent and age of landscape forest cover. Within suitable landscapes, toucans visited areas restored via tree planting ≥5 yr sooner and ≥2× more often than plots restored via natural regeneration. Tree plantations in suitable toucan habitat at the landscape scale had LSAD tree recruitment communities that were 2–3× richer in species than plantations in poor toucan habitat, and 71% (15/21) of all recruiting LSAD tree species were found only in plantations where landscape habitat was suitable for the largest toucan, Ramphastos ambiguus. Results support a multi-spatial-scale model for predicting toucan-mediated dispersal of LSAD trees. Tree planting increases toucan visitation and LSAD tree recruitment, but only within landscapes that represent suitable toucan habitat. More broadly, habitat suitability modeling for key seed dispersers can help prioritize restoration actions within heterogenous landscapes.