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• New evaluation method to detect physiological stress in fruit trees by airborne hyperspectral image spectroscopy

  37-40.

  J. Tamás

  Views:

  165

  Nowadays airborne remote sensing data are increasingly used in precision agriculture. The fast space-time dependent localization of stresses in orchards, which allows for a more efficient application of horticultural technologies, could lead to improved sustainable precise management. The disadvantage of the near field multi and hyper spectroscopy is the spot sample taking, which can apply independently only for experimental survey in plantations. The traditional satellite images is optionally suitable for precision investigation because of the low spectral and ground resolution on field condition. The presented airborne hyperspectral image spectroscopy reduces above mentioned disadvantages and at the same time provides newer analyzing possibility to the user. In this paper we demonstrate the conditions of data base collection and some informative examination possibility. The estimating of the board band vegetation indices calculated from reflectance is well known in practice of the biomass stress examinations. In this method the N-dimension spectral data cube enables to calculate numerous special narrow band indexes and to evaluate maps. This paper aims at investigating the applied hyperspectral analysis for fruit tree stress detection. In our study, hyperspectral data were collected by an AISADUAL hyperspectral image spectroscopy system, with high (0,5-1,5 m) ground resolution. The research focused on determining of leaves condition in different fruit plantations in the peach orchard near Siófok. Moreover the spectral reflectance analyses could provide more information about plant condition due to changes in the absorption of incident light in the visible and near infrared range of the spectrum.

• Economics of apple-storage I: Comparative time series analysis of apple producer prices in Germany and Hungary

  75-79.

  Z. Lakner

  F. Apáti

  Views:

  201

  Based on standard econometric methods the article analyses the time series of fresh apple producer prices in domestic markets of Germany and Hungary. In Germany, as a consequence of high storage capacities the quantity offered in different parts of the season is relatively stable, that’s why only a rather limited price increasing can be detected. In Hungary, as a consequence of the limited storage capacity this fluctuation is much more important. The modern methods of time series analysis (ARIMA models, stepwise regression) can be efficiently applied for forecasting of price movements.

• Determination of chlorophyll content in case of peach leaf curl disease (Taphrina deformans) with spectral analysis

  49-52.

  P. Riczu

  Gy. Bíró

  E. Sulyok

  A. Nagy

  J. Tamás

  Z. Szabó

  Views:

  292

  One of the most important conditions of high quality fruit production is the early detection of hytopathologycal infections. The most dangerous disease of peach (Prunus persica) is the Taphrina deformans, which causes serious damages mainly in the years where the weather condition is cool and wet. In this study, healthy and naturally diseased leaves by peach leaf curl were investigated in the laboratory of University of Debrecen, CAAES, Institute of Water and Environmental Management. Both of hyperspectral measurement and the values of spectrophotometer shown the chlorophyll content of diseased leaves were lower than the healthy samples. Based on the experiments the water status of investigated leaves established the infected leaves contained more water in their tissues.

• Vineyards characteristic by using GIS and refl ectance measurements on the Nagy-Eged hill in Hungary

  57-60.

  T. Fórián

  A. Nagy

  P. Riczu

  L. Mézes

  J. Tamás

  Views:

  193

  Our investigation was carried out in vineyards on Nagy-Eged hill in Hungary. Grapevine growing plays an important role in Eger Vine Regions. In the grapevine cultivation it becomes necessary to know the requirements of vineyards along the best geographical situation using available cultivation and examination technology to achieve better and quality produce. This study reviews applicability of the different spatial analyst techniques in vineyard especially models based on surface relief and the new technology of hyperspectral analysis. The spectral alteration was examined between different health status and leaves infected by Eriophyes vitis to defi ne spectral characteristics. Thus reflectance measurements could also support to evaluate airborne hyperspectral images with the help of the spectral library.

• Colour and water content detection of sweet cherry by portable spectrometer

  23-26.

  A. Nagy

  J. Tamás

  M. Soltész

  J. Nyéki

  Z. Szabó

  Views:

  295

  Based on the most recent data, the average amount of sweet cherry produced in Hungary is around 10-12 thousand tons. Therefore fast and effective method is important for sweet cherry fruit quality analyses. The aim of the study was to examine the applicability of reflectance measurements for sweet cherry fruit quality analyses. In our experiment five cherry species (Vera, Cristalina, Germersdorfi, Noir de Mechet, Canada Giant) were examined in order to measure the spectral differences between species. Further more, spectral alteration was examined between different health and maturity status of the fruits in the case of a specified, the Germesdorfi species. The four new indices are appropriate tools for cherry quality analysis. Thus reflectance measurements can also support more precise and automated fruit selections. The methods for the differentiation of species could also be viable at a concerned habitat; however, the climate, habitat and soil conditions strongly affect the yield quality. Concerning the fast determination of water content, WBI could be a reliable method for the assessment