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Modelling and comparing two canopy shapes using FEM
71-74.Views:112Central leader and Vase form canopy models were built using FEM. Their main characteristics were chosen to be the same. The models were virtually exposed to the effect of steady-state horizontal forced vibration in the frequency range of 0-20 Hz. Acceleration-frequency curves were calculated and drawn to find the best frequency values for the effective detachment and also to see the acceleration differences in the limbs. For the same purpose the direction of shaking was also changed. It was found that for the Central leader canopy shape multidirectional shaking would bring uniform detachment while for the Vase form trees also the unidirectional shakers were appropriate. The acceleration achieved for the Vase form models were much higher than for the Central leader type. The acceleration-frequency curve of the shaker unit can be used to find the best frequency for shaking.
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Mathematical and Statistical Modelling of Impact Symptoms and Application to Tomato
75-80.Views:104Drop tests were performed with different tomato cultivars. „Rupture" and „no rupture" conditions were determined as results. The proportion of „rupture" was shown versus the drop height and the relationships were described by a logistic function. The different cultivars are compared on this basis. The tests and results are suitable for the evaluation of stress sensitivity of tomatoes.
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What mechanisms are involved in cabbage-clover intercropping and a further proof of the 'host plant quality' hypothesis
47-51.Views:120Over 10 years of field trials show reductions of most of the pests in Brassicas undersown by clover. The pest-reducing effects are due to the 'appropriate / inappropriate landings' hypothesis (Finch, 1996), and the 'host plant quality' hypothesis (Theunissen, 1994). To find out the mechanisms within the 'host plant quality' hypothesis in the most promising intercropping (collards undersown by clover) glasshouse experiments were conducted to see whether intercropping influences the mean relative growth rate, fecundity and time of maturity of Myzus persicae (Sulzer) (Homoptera: Aphididae) a common pest of Brassicas.
The treatment modelling intercropping showed the smallest mean relative growth rate, delayed the maturity and slowed down the growth of cabbages. The treatment modelling monocropping showed the highest mean relative growth rate and the maturity was reached earlier. These results may indicate that intercropping delays the growth of settled aphid populations, giving another proof that in the case of clover undersown cabbages the 'host plant quality' hypothesis is likely to be acting. The differences between treatments where the roots of clover and cabbages were separated and allowed to grow together suggest that the effect is via the roots by competition.
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Pilot study for irrigation modelling of a pear plantation
81-84.Views:267Our investigation was carried out in the area of Fruit growing Research and Consultant non-profit company, at Újfehértó. The pear requires large water quantity, but this pear plantation hasn’t irrigation system not yet. This study reviews the drainage conditions of the area based on digital elevation model, and examined the canopy cover of pear trees by evaluating of the hyperspectral image. Our aims were to determine the exact watershed based irrigation modelling and determining of the canopy% of the pear orchard to facilitate a precision irrigation decision support system.
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Climate change impacts and product lines
79-83.Views:191This paper summarizes the main effects of extreme weather events on agricultural production and demonstrates their economic consequences. For cost-benefit analysis of economic impacts and for determination of risk levels simulation models are needed that contains the relationship between product line levels and elements. WIN-SIM model is developed for this goal, specialized for wine production. The model is suitable to analyze the market share, the cost and income relations as well as the relation structure of the product lines. The four levels of the model (site, vine growing, wine production and wine market levels) have individual values added from the aspect of end product, where the product line sets out from the site level and gets through the levels up to the consumer segments. Theoretically, all elements can be connected to any element of the next level and sublevel, but there are “prohibited contacts” because of professional, regulation or production practice reasons.
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Some structural characteristics of the flowers of apple cultivars with different susceptibilty to fire blight
21-23.Views:113Several morphological characters of the hypanthium (size and form of the surface, the shape of the hypanthium) and anatomical traits (number and pattern of stomata) of apple cultivars (Malus domestica L.) with different susceptibility to fire blight were studied. The size of hypantium surface was calculated by modelling the hypanthium with a truncated cone. Three types of hypanthium surface form have been revealed: straight, convex and a complex "shouldered" one. The angle between the style and the wall of the hypanthium was narrow or wide. The stomata on the hypanthium surface can be arranged in a zone in the middle third of the hypanthium or dispersed more or less evenly. The number of stomata/flower substantially differed among the cultivars examined. The highest stomata number was detected in the flowers of the tolerant cultivar (Freedom)
No single characteristics of the hypanthium could convincingly be correlated with susceptibility to fire blight. We suggest, however, that combination of morphological properties that sustain moist environment in the hypanthium contribute to susceptibility.