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L M (l + m)
Selected AbstractsEffect of inoculum type and timing of application of Coniothyrium minitans on Sclerotinia sclerotiorum: control of sclerotinia disease in glasshouse lettucePLANT PATHOLOGY, Issue 5 2004E. E. Jones The effects of Coniothyrium minitans inoculum quality and an 8-week interval between inoculum application and crop planting on sclerotinia (Sclerotinia sclerotiorum) disease in three successive lettuce crops were investigated in a glasshouse trial. Spore suspensions of three isolates of C. minitans (Conio, IVT1 and Contans) applied at 108 CFU m,2 and a standard Conio maizemeal,perlite application (06 L m,2, 1011 CFU m,2) were assessed for their ability to control S. sclerotiorum. Only the maizemeal,perlite inoculum (isolate Conio) consistently reduced sclerotinia disease. In the third lettuce crop only, isolates IVT1 and Contans formulated by Prophyta and isolate IVT as an oil,water formulation, all applied as spore suspensions, reduced disease at harvest compared with the untreated control. Recovery, viability and C. minitans infection of sclerotia buried during the 8-week period prior to each of the three lettuce crops, and of sclerotia formed on the crop, were tested. Only the maizemeal,perlite inoculum (isolate Conio) reduced the recovery of sclerotia buried in soil for weeks between inoculum application and crop planting, reducing their viability and increasing infection by C. minitans. Eight weeks was sufficient to enable C. minitans to infect sclerotia of S. sclerotiorum, and may account for disease control. After harvest of the second and third crops, maizemeal,perlite treatment (isolate Conio) reduced the number and viability of sclerotia recovered on the soil surface and increased infection by C. minitans compared with spore-suspension treatments. The effect of inoculum concentration and the influence of soil temperature (varying with time of year) on infection of sclerotia by C. minitans are discussed. [source] Coconut water as a potential resource for cellulose acetate membrane preparationPOLYMER INTERNATIONAL, Issue 3 2008Cynthia Radiman Abstract BACKGROUND: Cellulose acetate membranes are frequently used for pressure-driven membrane processes. The aim of this work was to prepare cellulose acetate membranes from nata-de-coco using coconut water as starting material. The use of this lignin-free material will certainly minimize the use of chemicals usually needed in the traditional pulps and substitute for the use of wood, which helps prevent global warming and preserves nature as well. RESULTS: Coconut water was fermented by Acetobacter xylinum for 6 days to produce nata-de-coco, which was then acetylated to produce cellulose diacetate with an acetyl content of 39.6%. Fourier transform infrared analysis showed characteristic peaks for the acetyl group at 1748 and 1236 cm,1. The resulting membranes made from the hydrolysis product showed a water flux of 210.5 L m,2 h,1 under an applied pressure of 2 kg cm,2 while the rejection coefficients of dextran T-500 and T-2000 solutions were 78 and 93.7%, respectively. CONCLUSION: Coconut water has a potential to be used in the fabrication of membranes by converting it to nata-de-coco and then to cellulose diacetate which gives an added value to its original nature. It is also highly competitive compared to the traditional pulps, by which acetylation decreases the degree of crystallinity of nata-de-coco resulting in higher membrane permeability. Copyright © 2007 Society of Chemical Industry [source] Nutritional niche separation in coexisting bog species demonstrated by 15N-enriched simulated rainfallAUSTRAL ECOLOGY, Issue 4 2009BEVERLEY R. CLARKSON Abstract Empodisma minus and Sporadanthus ferrugineus (both Restionaceae) coexist in New Zealand raised bogs, yet Sporadanthus have significantly more depleted 15N natural abundance signatures than coexisting Empodisma. Their root systems are spatially separated with Empodisma having a thick surface layer of about 50 mm of cluster roots overlying the deeper Sporadanthus roots. We hypothesized this root displacement allows Empodisma to preferentially access the primary N input from rainfall, thus establishing niche separation, and tested this using tracer stable isotopes. We aerially applied 1.6 mmol m,2 of 15N as (NH4)2SO4 chased by deionized water to simulate a rainfall event of 34 L m,2. Root/peat matrix cores were harvested after 5 h and analysed for 15N uptake. Approximately 80% of the tracer applied was recovered in the cores, with 90% of this recovered in the upper Empodisma cluster root layer. Seven weeks after application, young shoots of Empodisma were significantly enriched (mean ,15N = +7.21,; reference = ,0.42,), whereas those of coexisting Sporadanthus were not (mean ,15N = ,2.76,; reference = ,4.24,). However, we were unable to quantify the 15N uptake because of the dilution effect of the large biomass. We calculated the contribution of biological nitrogen fixation as a possible alternative source of N in achieving niche separation. The acetylene reduction assay showed minor amounts of nitrogenase activity are associated with Empodisma and Sporadanthus roots (equivalent to 0.045 ± 0.019 and 0.104 ± 0.017 kg N ha,1 year,1 respectively). Our results suggest that the species acquire nutrients from different rooting zones, with Empodisma accessing nutrients at the surface from rainfall and Sporadanthus accessing nutrients from mineralization in deeper peat layers. Such niche differentiation probably facilitates species coexistence and may provide a mechanism for slowing the rate of competitive displacement during long-term succession. [source] Optimization of parabolic trough solar collector systemINTERNATIONAL JOURNAL OF ENERGY RESEARCH, Issue 4 2006Saad D. Odeh Abstract Process heat produced by solar collectors can contribute significantly in the conservation of conventional energy resources, reducing CO2 emission, and delaying global warming. One of the major problems associated with solar process heat application is fluctuation in system temperature during unsteady state radiation conditions which may cause significant thermal and operation problems. In this paper a transient simulation model is developed for analysing the performance of industrial water heating systems using parabolic trough solar collectors. The results showed that to prevent dramatic change and instability in process heat during transient radiation periods thermal storage tank size should not be lower than 14.5 l m,2 of collector area. Small periods of radiation instability lower than 30 min do not have significant effect on system operation. During these periods when water flow rate of collector loop is doubled the time required to restore system normal operating condition increased by a ratio of 1.5. Copyright © 2005 John Wiley & Sons, Ltd. [source] NOMENCLATURAL NOTE ON A THECADINIUM SPECIES (DINOPHYCEAE, GONYAULACALES), WHICH WAS DESCRIBED AS NEW INDEPENDENTLY THREE TIMES WITHIN TWO MONTHS,JOURNAL OF PHYCOLOGY, Issue 6 2005Mona Hoppenrath Three Thecadinium species, independently described as new in three separate publications, are actually regarded as conspecific. The combined plate formula is Po 3, 1a 6, 5-7/8c 5s 6,, 2,,. The size range of the species is 38,65 l m in length and 23,42 lm in depth. It has one or two strongly lobed chloroplasts. The correct name of the species is Thecadinium yashimaense Yoshimatsu, Toriumi et Dodge 2004. Thecadinium mucosum Hoppenrath et Taylor 2004 and Thecadinium foveolatum Bolch 2004 are taxonomical synonyms. This note clarifies the plate tabulation and other features of the species. [source] | ||||||||||