Download or read book Emergence and Development of Red Sorrel (Rumex Acetosella L.) and Lowbush Blueberry (Vaccinium Angustifolium Ait.) Ramets in Lowbush Blueberry Fields written by Scott Neil White and published by . This book was released on 2013 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: Field studies were established to evaluate the suitability of growing degree day (GDD, Tbase=0oC) models for predicting emergence and development of lowbush blueberry and red sorrel ramets and to conduct a demographic study of red sorrel in lowbush blueberry. Model predictions for initiation of lowbush blueberry ramet emergence, tip dieback, and flowering were 243, 692, and 389 GDD, respectively. Peak lowbush blueberry ramet emergence and tip dieback occurred around 928 and 1626 GDD, respectively. Peak blueberry bloom was observed between 552 and 565 GDD. Model prediction for the initiation of red sorrel ramet emergence was 92 GDD, and 10, 50, 90, and 95% emergence were predicted to occur at 279, 1322, 2536, and 2696 GDD, respectively. Red sorrel ramets therefore initiate emergence earlier than lowbush blueberry, and continue to emerge during important crop developmental processes in the non-bearing year. Model prediction for the initiation of red sorrel flowering was 289 GDD, and 10, 50, 90, and 95% flowering were predicted to occur at 376, 545, 877 and 1336 GDD, respectively. Red sorrel ramets therefore flowered during blueberry bloom and may interfere with crop pollination. Red sorrel ramet emergence was season-long but ramets suffered higher mortality during the bearing year. Red sorrel ramet mortality was higher in bare soil patches than within blueberry clones. A distinct overwintering red sorrel ramet population was identified and constituted the majority (>70%) of the population of flowering ramets. Seasonal recruitment of new red sorrel seedlings occurred and indicates regular recruitment of new genets into established populations. Results of field studies initiated a series of greenhouse and growth chamber studies to investigate the roles of vernalization and photoperiod on red sorrel ramet development. Red sorrel ramets had an obligate requirement for vernalization and only flowered when transferred to long days after cold treatment. Ramets required vernalization for at least 10 weeks to induce flowering. Pre and post-vernalization ramet removal reduced flowering ramet density under both field and controlled conditions. Exposure of ramets to decreasing photoperiod prior to vernalization increased flowering frequency in one experiment and indicates a potential role of pre-vernalization stimuli in regulating ramet flowering.