Hou valse meeldauw eronder

Onlangs is een aantal uienrassen geïntroduceerd met resistentie tegen valse meeldauw. Maar zolang deze en andere ziekten nog niet zijn uitgebannen, blijven preventie en accurate bestrijding de sleutelwoorden. Het PPO-AGV zet de belangrijkste aantastingen op een rijtje. Valse meeldauw staat met stip op één

Experimental control strategies reducing the fungicide input at a practical scale

Phytophthora infestans is the most devastating disease in potato cultivation. Chemical control is necessary to ensure a healthy crop. At the same time Dutch governmental policy asks for a reduction of the environmental impact of potato late blight control by 75% in 2012 as compared to 1996-1998. The aim of the experiments was to compare Decision Support Systems with different approaches to blight risk management for their ability to reduce the fungicide input without compromising control efficacy. Considerable savings, up to 81% when compared to weekly, full dose rate, spray schedules, can be achieved by using information on cultivar resistance, length of the critical period and disease pressure to decide whether or not to spray. The subroutine calculating the potential for viable transport of spores is only effective on resistant varieties as the threshold was exceeded with every critical period on less resistant cultivars. Implications of the experimental control strategies for agricultural practise are discusse

Curatieve en eradicatieve (stop) werking van fungiciden tegen Phytophthora 2009

Er zijn 2 pottenproeven uitgevoerd, waarbij in de ene proef de curatieve werking en in de andere proef de eradicatieve (stop) werking van fungiciden of fungicidencombinaties werd onderzocht

Stoombehandelingen eerstejaars plantuien tegen valse meeldauw

In de winter van 2010-2011 zijn in opdracht van het Productschap Akkerbouw verschillende stoombehandelingsvarianten bij Ruvoma uitgevoerd. Namelijk bij 40, 42.5 en 45 ∘C, bij 85 en 95 % RV en gedurende één en twee dagen. De uitjes zijn vervolgens in een biotoets in de kas getoetst op kieming en systemische aantasting

Prevalence and co-occurrence of addictive behaviors among former alternative high school youth

Abstract Background and Aims Recent work has studied multiple addictions using a matrix measure, which taps multiple addictions through single responses for each type. Methods The present study investigated use of a matrix measure approach among former alternative high school youth (average age = 19.8 years) at risk for addictions. Lifetime and last 30-day prevalence of one or more of 11 addictions reviewed in other work (Sussman, Lisha & Griffiths, 2011) was the primary focus (i.e., cigarettes, alcohol, other/hard drugs, eating, gambling, Internet, shopping, love, sex, exercise, and work). Also, the co-occurrence of two or more of these 11 addictive behaviors was investigated. Finally, the latent class structure of these addictions, and their associations with other measures, was examined. Results We found that ever and last 30-day prevalence of one or more of these addictions was 79.2% and 61.5%, respectively. Ever and last 30-day co-occurrence of two or more of these addictions was 61.5% and 37.7%, respectively. Latent Class Analysis suggested two groups: a generally Non-addicted Group (67.2% of the sample) and a “Work Hard, Play Hard”-addicted Group that was particularly invested in addiction to love, sex, exercise, the Internet, and work. Supplementary analyses suggested that the single-response type self-reports may be measuring the addictions they intend to measure. Discussion and Conclusions We suggest implications of these results for future studies and the development of prevention and treatment programs, though much more validation research is needed on the use of this type of measure

Endocytosis of coacervates into liposomes

[Image: see text] Recent studies have shown that the interactions between condensates and biological membranes are of functional importance. Here, we study how the interaction between complex coacervates and liposomes as model systems can lead to wetting, membrane deformation, and endocytosis. Depending on the interaction strength between coacervates and liposomes, the wetting behavior ranged from nonwetting to engulfment (endocytosis) and complete wetting. Endocytosis of coacervates was found to be a general phenomenon: coacervates made from a wide range of components could be taken up by liposomes. A simple theory taking into account surface energies and coacervate sizes can explain the observed morphologies. Our findings can help to better understand condensate–membrane interactions in cellular systems and provide new avenues for intracellular delivery using coacervates

Biomolecular Chemistry in Liquid Phase Separated Compartments

Biochemical processes inside the cell take place in a complex environment that is highly crowded, heterogeneous, and replete with interfaces. The recently recognized importance of biomolecular condensates in cellular organization has added new elements of complexity to our understanding of chemistry in the cell. Many of these condensates are formed by liquid-liquid phase separation (LLPS) and behave like liquid droplets. Such droplet organelles can be reproduced and studied in vitro by using coacervates and have some remarkable features, including regulated assembly, differential partitioning of macromolecules, permeability to small molecules, and a uniquely crowded environment. Here, we review the main principles of biochemical organization in model membraneless compartments. We focus on some promising in vitro coacervate model systems that aptly mimic part of the compartmentalized cellular environment. We address the physicochemical characteristics of these liquid phase separated compartments, and their impact on biomolecular chemistry and assembly. These model systems enable a systematic investigation of the role of spatiotemporal organization of biomolecules in controlling biochemical processes in the cell, and they provide crucial insights for the development of functional artificial organelles and cells