Sheep and hair fescue are perennial, tuft forming grasses that spread by seed and form dense sods in wild blueberry fields. These sods compete with the crop for resources and hinder harvest. Field and greenhouse studies were conducted in 2015 to evaluate 1) the effect of sequential glufosinate and foramsulfuron applications on suppression of fescues in the greenhouse and field, and 2) efficacy of glufosinate and foramsulfuron on fescue seedlings when applied at 2, 4, 6, and 8 wk after seedling emergence in the greenhouse. Glufosinate applications at 750 and 1,005 g ai ha −1 followed by foramsulfuron application at 35 g ai ha −1 reduced fescue leaf number and biomass relative to foramsulfuron application alone in the greenhouse. In the field study, fescue flowering tuft density, tuft inflorescence height, seed production, and seed viability were reduced by foramsulfuron alone, but there was a trend towards lower seed production and tuft height when fescues were treated with glufosinate at 1,005 g ha −1 followed by foramsulfuron. Foramsulfuron caused low seedling mortality at all application timings evaluated, but glufosinate caused >90% mortality in seedlings when applied at 2, 4, 6, or 8 wk after seedling emergence. Our results suggest that sequential applications of these herbicides are less effective under field conditions relative to results obtained in the greenhouse, though burndown glufosinate applications may have a role in reducing fescue seedling recruitment. Additional research should be conducted to determine the effect of early spring and autumn glufosinate applications on fescue seedling recruitment and suppression of established fescue tufts with subsequent foramsulfuron applications. Nomenclature: Foramsulfuron; glufosinate; sheep fescue; Festuca ovina L. FESOV; hair fescue, Festuca filiformis Pourret FESTE; lowbush blueberry, Vaccinium angustifolium Aiton. Key words: Perennial crop, perennial grass, burndown herbicide, sequential herbicide.Festuca ovina y Festuca filiformis son gramíneas perennes que forman espigas, que se son dispersadas por semilla y que forman céspedes densos en campos de arándano silvestre. Estos céspedes compiten con el cultivo por recursos y dificultan la cosecha. En 2015 se realizaron estudios de campo y de invernadero para evaluar 1) el efecto de aplicaciones secuenciales de glufosinate y foramsulfuron sobre la supresión de plántulas de Festuca spp. cuando se aplicaron a 2, 4, 6, y 8 semanas después de la emergencia de las plántulas en el invernadero. Aplicaciones de glufosinate a 750 y 1,005 g ai ha −1 seguidas por una aplicación de foramsulfuron a 35 g ai ha −1 redujeron el número de hojas y la biomasa de Festuca spp. en relación con aplicaciones de sólo foramsulfuron en el invernadero. En el estudio de campo, la densidad de inflorescencias, la altura de la inflorescencia, la producción de semilla, y la viabilidad de la semilla fueron reducidas con la aplicación de foramsulfuron solo, pero hubo una tendencia hacia una menor producción de semilla y de altura de infloresc...

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The organic acid concentration in apple (Malus ×domestica) juice is a major component of hard cider flavor. The goal of this study was to determine if the malic acid markers, Ma1 and Q8, could classify the titratable acidity concentration in cider apple accessions from the United States Department of Agriculture Malus germplasm collection into descriptive classifications. Our results indicate that for diploid genotypes, the Ma1 marker alone and the Ma1 and Q8 markers analyzed together could be used to predict cider apple acidity (P < 0.0001). Alone, the Ma1 marker categorized acidity into low (<2.4 g⋅L−1), medium (2.4–5.8 g⋅L−1), and high (>5.8 g⋅L−1) groups. The combination of Ma1 and Q8 markers provided more specificity, which would be useful for plant breeding applications. This work also identified a significant difference (P = 0.0132) in acidity associated with ploidy. On average, the triploids accessions had 0.33 g⋅L−1 higher titratable acidity than the diploid accessions. Based on the results of this work, we propose a genetics-based classification system for cider apples with the acidity component defined by the Ma1 and Q8 markers.

Societal Impact StatementFermented "hard" cider is currently experiencing a resurgence in popularity. While there is a long history of cultivating apple trees with fruit quality characteristics intended specifically for cider production, there is a dearth of cider-specific apple production in many emerging cider producing regions, such as North America. To help bolster the emerging cider industry and identify topics that warrant further research, this review article describes the biochemistry and physiology of apple fruit quality from a cider producing perspective.