Szalicilsav által szabályozott védekező mechanizmusok vizsgálata gabonafélékben = Investigation of protective mechanisms controlled by salicylic acid in cereals

A pályázat célja az volt, hogy megvizsgáljuk az exogén szalicilsav (SA) hatását különböző abiotikus stresszek során, valamint hogy megvizsgáljuk hogyan alakul az endogén SA szint stresszkörülmények között gabonafélékben. Hidegstressz során nem volt különbség a kontroll és a SA kezelt növények membránlipidjeinek zsírsavösszetételében, míg a SA előkezelés megemelte a putreszcin és a spermidin szintjét, és ez is hozzájárul valószínűleg a SA védőhatásához. Szárazság stressz ellen a SA nemcsak, hogy nem nyújtott védelmet, hanem fokozta annak károsító hatását. Nehézfémstressznél (Cd) a SA kezelés hatására gyökérben jobban csökkent a fitokelatin szintáz enzim aktivitása, míg levélben megnőtt. Szárazság stressz során kukorica (Norma hibrid) mind a kötött, mind a szabad endogén SA szint lecsökkent gyökérben, míg levélben drasztikus stressz hatására megnőtt. NaCl kezelésnél a levélben a szabad SA szint kismértékben megnőtt, gyökérben nem változott, a kötött mind levélben, mind gyökérben lecsökkent. Cd stressz során gyökérben mind a szabad mind a kötött SA tartalom megnőtt. Az abszcizinsav kezelés normál hőmérsékleten nem befolyásolta az SA szintet, míg egy nap 5°C-os alacsony hőmérsékleti stressz során a szabad SA szint megnőtt, a kötött pedig lecsökkent, mind levélben, mind gyökérben. Ezek alapján megállapíthatjuk, hogy a szalicilsav szerepet játszik abiotikus stresszek során. | The aim of the project was to examine the effect of exogenous salicylic acid (SA) during various types of abiotic stress, and to determine how the endogenous SA level changed under stress conditions in cereals. During cold stress no difference was observed in the fatty acid composition of membrane lipids between control and SA-treated plants, while preliminary treatment with SA caused a rise in the levels of putrescine and spermidine, probably contributing to the protective effect of SA. Rather than providing protection against drought stress, SA made the damage more severe. In the case of heavy metal (Cd) pollution the phytochelatin synthase enzyme activity was further reduced by SA in the roots, but increased in the leaves. During drought stress there was a reduction in the level of both bound and free endogenous SA in the roots of maize (hybrid Norma), while it increased in response to drastic stress in the leaves. Treatment with NaCl caused a slight increase in the free SA level in the leaves, while no change was observed in the roots; the bound SA level declined in both leaves and roots. During Cd stress there was an increase in both free and bound SA content in the roots. At normal temperature abscisic acid treatment had no effect on the SA level, but after one day of low temperature stress (5°C) there was an increase in free SA and a drop in bound SA in both leaves and roots. It is thus clear that salicylic acid plays a role in the response to abiotic stress factors

DESIGN TASKS SCHEDULING USING GENETIC ALGORITHMS

This paper deals with a modelling and optimization method that is capable of the product structure based optimization of design processes. The processes were modelled with Design Structure Matrix. Guided stochastic search techniques were applied when finding the optimal task schedule. The impact of the probability of mutation and crossover and the two different selection processes on searching was examined. Further investigations were completed in order to multi-object optimize the time and cost of design processes

Laboratory and numerical investigation of direct shear box test

In agriculture, food, chemical, plastic and pharmaceutical industries for designing and operating machines, it is essential to determine the mechanical parameters of the processed granular materials. In most cases, these characteristics are the internal friction angle, the contact cohesion developed by the surface moisture and the apparent cohesion occurred by the shape of the granular material. Further physical quantities are required to characterize the motion state of the particles, which were determined by laboratory measurements in this study. Hulled mil- let was used for the measurements because its geometric shape can be modeled as sphere in the numerical investigations with good approximation. The porosity, the particle and bulk den- sity of the hulled millet were determined by means of an air pycnometer in case of several moisture content. Using laboratory direct shear box test, under standard conditions, the shear strength of the cohesive liquid bridges and the internal friction angle in the bulk were deter- mined. The results obtained were used for input parameters of a discrete element model. The aim of this research was to determine the micromechanical parameters by simulation, based on the macromechanical results of the hulled millet bulk during laboratory measurements