Influences of precipitation and temperature trend on maize yields

Maize yield for three decade period of the last century (1961-1990) were in Hungary for 15% higher than in Croatia (means 3.81 and 4.39 t/ha, respectively) and this trend was continued in the 1996-2007 period. However, amplitude of maize yields (differences among year (for the 1996-2007) in Hungary were higher (from 3.60 to 7.56 t/ha) than in Croatia (from 3.86 to 6.92 t/ha). Aim of this study was testing maize yield, precipitation and air-temperature variations in four Counties (Croatia: Vukovarsko-Srijemska =VSC and Virovitiţko-Podravska =VPC; Hungary: Békés = BC and Fejér =FC). Mean yield in VSC for 1996-2007 period was for 16% higher than in VPC. Yields in three less favorable years (LFY: 2000, 2003 and 2007) were considerably lower (means 5.22 and 4.41 t/ha, for VSC and VPC, respectively) than in three more favorable years (MFY: 1997, 2002 and 2005) years (means 7.50 and 7.00, respectively). Precipitation (means of two sites: Osijek and Virovitica) in 3-months period June-August was in LFY for 58% lower than in MFY (129 mm and 305 mm, respectively). At the same time, air-temperatures were for 2.0°C higher (22.7 and 20.7°C, respectively). Mean yield in BC for 1996-2007 period was for 21% higher than in FC. Yields in three LSY were considerably lower (means 3.78 and 3.79 t/ha, for BC and FC, respectively) than in three MFY (means 6.13 and 7.30 t/ha, respectively). Precipitation (means of two sites: Békéscsaba and Székesfehérvár) in 3-months period June-August was in LFY for 51% lower (115 mm and 235 mm, respectively) and air-temperatures were for 1.9°C higher (22.1 and 20.2°C, respectively) than in MFY. Precipitation and temperature trends for LFY and MFY in two sites of both countries were similar with emphasis that in Hungary they were negligible lower

Ultrasonic intensification as a tool for enhanced microbial biofuel yields

peer-reviewedUltrasonication has recently received attention as a novel bioprocessing tool for process intensification in many areas of downstream processing. Ultrasonic intensification (periodic ultrasonic treatment during the fermentation process) can result in a more effective homogenization of biomass and faster energy and mass transfer to biomass over short time periods which can result in enhanced microbial growth. Ultrasonic intensification can allow the rapid selective extraction of specific biomass components and can enhance product yields which can be of economic benefit. This review focuses on the role of ultrasonication in the extraction and yield enhancement of compounds from various microbial sources, specifically algal and cyanobacterial biomass with a focus on the production of biofuels. The operating principles associated with the process of ultrasonication and the influence of various operating conditions including ultrasonic frequency, power intensity, ultrasonic duration, reactor designs and kinetics applied for ultrasonic intensification are also described

Morphological and molecular differentiation of the Croatian populations of Quercus pubescens Willd. [Fagaceae]

Taxonomy of the genus Quercus L. is very complicated and often controversial because of its great variability and intense gene flow among the related species. The purpose of this research was to determine morphological and molecular variation, relationships and taxonomic status of the Croatian populations of Quercus pubescens Willd. using morphological analysis of the leaves and RAPD-PCR technique. The results of the morphological and molecular analyses were very similar, both showing differentiation of the southern (Mediterranean) from the northern (Continental) pubescent oak populations. These two groups were clearly separated and the estimated gene flow among the populations that belong to different groups (Nm=1.38) is significantly less than among the populations that belong to the same group (Nm=3.70). The obtained results were compared to the available studies. This study confirms a high variability of the Q. pubescens populations, but differences were not so big to confirm the opinion of existence of several species in this area. The conclusion is that the southern Croatian populations could be pure Q. pubescens populations, while the peculiarities of the northern Croatian populations originate probably from the Q. petraea introgression