Predictive theory on how plant diversity promotes herbivore suppression through movement patterns, host associations, and predation promises a potential alternative to pesticide-intensive monoculture ...crop production. We used meta-analysis on 552 experiments in 45 articles published over the last 10 years to test if plant diversification schemes reduce herbivores and/or increase the natural enemies of herbivores as predicted by associational resistance hypotheses, the enemies hypothesis, and attraction and repellency model applications in agriculture. We found extensive support for these models with intercropping schemes, inclusion of flowering plants, and use of plants that repel herbivores or attract them away from the crop. Overall, herbivore suppression, enemy enhancement, and crop damage suppression effects were significantly stronger on diversified crops than on crops with none or fewer associated plant species. However, a relatively small, but significantly negative, mean effect size for crop yield indicated that pest-suppressive diversification schemes interfered with production, in part because of reducing densities of the main crop by replacing it with intercrops or non-crop plants. This first use of meta-analysis to evaluate the effects of diversification schemes, a potentially more powerful tool than tallies of significant positive and negative outcomes (vote-counting), revealed stronger overall effects on all parameters measured compared to previous reviews. Our analysis of the same articles used in a recent review facilitates comparisons of vote-counting and meta-analysis, and shows that pronounced results of the meta-analysis are not well explained by a reduction in articles that met its stricter criteria. Rather, compared to outcome counts, effect sizes were rarely neutral (equal to zero), and a mean effect size value for mixed outcomes could be calculated. Problematic statistical properties of vote-counting were avoided with meta-analysis, thus providing a more precise test of the hypotheses. The unambiguous and encouraging results from this meta-analysis of previous research should motivate ecologists to conduct more mechanistic experiments to improve the odds of designing effective crop diversification schemes for improved pest regulation and enhanced crop yield.
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BFBNIB, FZAB, GIS, IJS, INZLJ, KILJ, NLZOH, NMLJ, NUK, OILJ, PNG, SAZU, SBCE, SBMB, UL, UM, UPUK, ZRSKP
Commercial hop ('Humulus lupulus' L.) production occurs predominantly in temperate climates. The objectives of this study were to characterize the phenology of hops under subtropical climatic ...conditions and to determine the growth and yield potential. Two field experiments were conducted in Florida, southeastern United States. Rhizomes were planted in April. Data were collected during the establishment year. In the first experiment, we evaluated 7 American, 5 European, and 1 Japanese cultivars in a randomized complete block design. Bine height, main bine number, lateral shoot number, and dry cone yield (10% moisture) were recorded. Yield varied considerably, ranging from 0 to 197 kg ha-1. The top three yielding cultivars were 'Cascade', 'CTZ', and 'Nugget', all of which were American cultivars. Yield had positive correlations with main bine number and lateral shoot number, but it had no significant correlation with bine height. In the second experiment, we determined the duration of each phenological stage in 'Cascade'. Reproductive phenology was characterized by premature and nonsynchronous flowering. Prolonged flowering resulted in multiple harvests over 61 days, starting in mid-June. We also evaluated crop management treatments, which consisted of three levels of hill spacing (76, 91, and 107 cm) and two nitrogen (N) rates (109 and 130 kg ha-1) in a factorial combination. Treatments were arranged in a split-plot design with hill spacing as the main-plot factor. Yield on a per-area basis increased with reducing hill spacing and increasing N rate by 41% and 38%, respectively. Our results demonstrate unique reproductive phenology of hops under subtropical climatic conditions, which prevents once-overharvest but enables the off-season supply of fresh hops over an extended period. This study provides a benchmark to develop production strategies for hops suitable to subtropical climates.
•In a subtropical climate, photoperiod manipulation allows two crops of hops a year.•Photoperiod extension with LED (>16.9 hr, <1 µmol m–2 s–1) inhibits flowering in hops.•Hop yield and quality vary ...between spring and fall seasons in the subtropics.•Hops have high phenological plasticity with no chilling requirement for bud break.
Hops (Humulus lupulus L.) have an ancient history of cultivation in temperate climates primarily as an ingredient of beer. However, growing hops in subtropical or tropical climates has been challenging because of non-optimal day length conditions. We examined the potential of subtropical hop production with photoperiod manipulation. ‘Cascade’ hops were grown in Florida, United States with extended day length (>16.5 h) using light-emitting diode (LED) bulbs to inhibit flowering until sufficient vegetative growth was achieved. Phenology, plant growth, yield, and cone quality data were collected during the first two years after planting. With as little as 0.47 μmol m–2 s–1, photoperiod extension was effective in inhibiting flowering, while promoting vegetative growth. Uniform flowering was induced upon the discontinuation of photoperiod extension. As a result, plants achieved two growing cycles per year, with the spring and fall growing seasons running from February to July and July to December, respectively. Yield increased by 92 % from Year 1 to Year 2 but decreased by 37 % from the spring to fall growing season. The maximum yield was 465 kg ha–1 in Year 2 Spring. Cone quality was greatly affected by both year and season, with α acid, β acid, and total oil concentrations ranging from 2.7 % to 6.2 %, 1.9 % to 3.2 % and 0.14 to 0.53 mL/100 g, respectively. These results demonstrate that, with an aid of photoperiod manipulation for flowering control, ‘Cascade’ hops exhibit high phenological plasticity and acclimation capacity to subtropical climatic conditions. This study provides a foundation for developing the double-season hop production system in a subtropical climate.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UILJ, UL, UM, UPCLJ, UPUK, ZAGLJ, ZRSKP
Lúpulo, un ingrediente esencial de la cerveza, tiene el potencial de desarrollarse como un cultivo alternativo viable en Florida. Este artículo es parte de una serie más grande que revisará los ...desafíos de la producción de lúpulo, basado en experiencias en nuestro campo de investigación en el UF/IFAS Gulf Coast REC. Written by S. Agehara, A. Acosta-Rangel, M. Gallardo, and G. Vallad, translated by M. Gallardo, and published by the UF/IFAS Horticultural Sciences Department.
Hops (Humulus lupulus L.), an essential ingredient in beer, have potential to develop as a viable alternative crop in Florida. In our surveys, many breweries have expressed strong interest in using ...locally grown hops. However, hop production is plagued by many diseases, most of which were inadvertently introduced through the movement of contaminated planting material. The primary purposes of this new 7-page article are to prevent the introduction of these diseases into the state and to provide recommendations for selecting and preparing planting material for successful hop production in Florida. This publication of the UF/IFAS Horticultural Sciences Department is part of a larger series that will review the challenges of hop production, based on research experience at the UF/IFAS Gulf Coast Research and Education Center (UF/IFAS GCREC) in Balm, FL.https://edis.ifas.ufl.edu/hs1381
Photosynthesis-related traits, encompassing aspects such as absorbance, chlorophyll content, fluorescence, quenching ratio of incoming light, and photochemical efficiency, are pivotal characteristics ...directly related to photosynthesis carbon gain with important implications for overall tree physiology and fruit production. In this study, we conducted an examination of 71 citrus accessions and varieties, utilizing over 56,000 single nucleotide polymorphisms and 37 leaf reflectance parameters. Pairwise correlation analysis revealed clusters of interrelated traits organized into four distinct groups. The observed trait variations were found to have associations with the citrus phylogeny. Through genome-wide association studies, we identified a total of 125 genomic loci and 189 potentially associated genes responsible for the observed trait variations. The potential network and biological pathways influencing the variability of these biophysical variables within the citrus collection are also discussed.
El lúpulo (Humulus lupulus L.) es un ingrediente esencial en la elaboración de cerveza, que agrega amargura y sabor a la cerveza. Impulsada por el reciente movimiento de la cerveza artesanal, la ...producción de lúpulo se está expandiendo hacia estados no tradicionales en la producción de lúpulo. En Florida, aunque la producción comercial de lúpulo es casi inexistente, la cantidad de cervecerías artesanales aumentó de 45 en 2011 a 285 en 2018, y el impacto económico de la industria de la cerveza artesanal en Florida supera los $3 mil millones. Este nuevo artículo de 7 páginas, escrito por Shinsuke Agehara, Aleyda Acosta-Rangel, Zhanao Deng, Jack Rechcigl y Simon Bollin, traducido por Mariel Gallardo y publicado por el Horticultural Sciences Department de UF/IFAS, proporciona pautas y consideraciones para construir el sistema de tutorado para lúpulo y su establecimiento en Florida, utilizando como modelo, el campo de investigación del UF/IFAS Gulf Coast Research and Education Center (GCREC).https://edis.ifas.ufl.edu/hs1408
Este artículo describe las prácticas de manejo del cultivo y horas de mano de obra necesarios para la producción de lúpulo a pequeña escala en Florida con el objetivo de ayudar a los productores a ...tomar decisiones de inversión y de manejo de campo. This new 6-page publication of the UF/IFAS Horticultural Sciences Department was written by Shinsuke Agehara, Mariel Gallardo, Aleyda Acosta-Rangel, Zhanao Deng, Jack Rechcigl, Tianyuan Luo, and Qi Qiu, and translated by Mariel Gallardo.
The booming craft beer industry, rising prices of hops, and demand for locally-produced ingredients have recently increased interest in local hop production among growers and brewers. This article ...describes crop management practices and labor inputs required for small-scale hop production in Florida, with the aim of assisting growers with investment and farm management decisions. It is part of a larger series that will review the challenges of hop production in Florida, based on research experience at the UF/IFAS Gulf Coast Research and Education Center in Balm, FL. This new 6-page publication of the UF/IFAS Horticultural Sciences Department was written by Shinsuke Agehara, Mariel Gallardo, Aleyda Acosta-Rangel, Zhanao Deng, Jack Rechcigl, Tianyuan Luo, and Qi Qiu.https://edis.ifas.ufl.edu/hs1409
Hops (Humulus lupulus L.) are an essential ingredient in brewing, adding bitterness and flavor to beer. Driven by the recent craft beer movement, hop production is expanding into nontraditional ...hop-producing states. In Florida, while commercial hop production is almost nonexistent, the number of craft breweries in Florida increased from 45 in 2011 to 285 in 2018, and the economic impact of Florida?s craft beer industry exceeds $3 billion. This new 7-page article, written by Shinsuke Agehara, Aleyda Acosta-Rangel, Zhanao Deng, Jack Rechcigl, and Simon Bollin and published by the UF/IFAS Horticultural Sciences Department, provides guidelines and considerations for building a hop yard in Florida, using the UF/IFAS Gulf Coast Research and Education Center’s research hop yard as a model.https://edis.ifas.ufl.edu/hs1354
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