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  • The role of leaf area and photosynthesis in optimising the sowing date of maize
    5-10
    Views:
    120

     

    Our sowing date experiment took place in the Demonstration Garden of Institution of Plant Sciences, Agricultural Center of University of Debrecen, in 2012–2014. The thesis contains data of test year 2014. Our purpose, besides several other examinations, was to observe how sowing date influences leaf area index and activity of photosynthesis of maize hybrids, and how those factors affect fruiting. In the experiment we monitored the change of the leaf area index and the photosynthesis of hybrids with four different growing seasons.

    Based on the results, it can be concluded that most of the examined hybrids reached their smallest leaf area with the third sowing date and with the highest yield results. Hybrid Da Sonka had the largest leaf area (4.10 m2 m-2), and hybrid DKC 4590 produced the highest yield (13.16 t ha-1)

    with the third sowing date.

    During testing the photosynthetic capacity, the extremely high performance of the youngest plants with the third sowing date is outstanding, which can be explained by the different ripening periods. Examination of the correlation between the photosynthetic capacity and the yield, by linear regression analysis, also proves that photosynthesis has a determinative role in fruiting.

    The results obtained confirm that not only the environmental and agricultural factors in the growing season have effect on the yield, but also other factors like the leaf area index and the photosynthesis are determinative parameters, and all those factors together, modifying effects of each other, develop average yields.

  • Comparison of Reproductive Performance of the Roe Deer (Capreolus capreolus, L.) Among Different Regions
    41-46
    Views:
    81

    The potential and actual number of offspring of roe deer and the difference between these figures (prenatal and postnatal loss) significantly vary in each population yearly. The objective of this study is to examine the potential and actual number of offspring, the number of losses, and to find a link between the most important biological characteristics of does (body weight – BW, condition – KFI) and the number of raised offspring on four territories on the Great Hungarian Plain.
    Where the number of corpora lutea (CL) is the highest, there the losses are the highest as well, and the number of raised offspring is the lowest (region I.). Here, the rearing loss is double that of the weakest territory (region IV.). Rearing losses can be associated with the fenotype of does (BW, KFI) but environmental factors also have determinative importance. Where the number of twin-calving does was the highest, I found four times more does without a fawn than where the number of twin-calving does was the lowest. The nursing success was the best (the losses were lowest) in the region where the potential offspring (number of CL) was also the lowest, but the coverage of the habitat and the proportion of forests were largest. The food supply for the animals in autumn and winter are not enough, the structure of the habitat has to be improved as well, so that it might become adequate for game protection in extreme weather conditions.
    The results have to be considered as preliminary ones. It is essential to continue and extend the research to increase the reliability of the results.

  • Andrological examination of Hungarian Large White and Landrace boars
    5-10
    Views:
    209

    The Hungarian Large White and Hungarian Landrace pig breeds have outstanding lifetime performance, production parameters and crossbreeding ability. Nevertheless, during the recent decades, these breeds could not compete with the West European hybrid pigs concerning on production results. In this study, we made a complex andrological evaluation of boars in different Hungarian nucleus breeding stocks. After taking blood and semen samples, performing gonadotropin-releasing hormone (GnRH) challenge, ultrasonic and thermographic examinations were done. Laboratory tests were accomplished in reproduction labs of NARIC ABNMS. Our goal was to determine the reproductive performances of boars and collect samples for future genetic examinations, respectively.

  • Agronomic research in Martonvásár, aimed at promoting the efficiency of field crop production
    89-93
    Views:
    117

    The effect of crop production factors on the grain yield was analysed on the basis of three-factorial experiments laid out in a split-split-plot design. In the case of maize the studies were made as part of a long-term experiment set up in 1980 on chernozem soil with forest residues, well supplied with N and very well with PK. The effects of five N levels in the main plots and four sowing dates in the subplots were compared in terms of the performance of four medium early hybrids (FAO 200). In the technological adaptation experiments carried out with durum wheat, the N supplies were moderate (2010) or good (2011), while the P and K supplies were good or very good in both years. Six N top-dressing treatments were applied in the main plots and five plant protection treatments in the subplots to test the responses of three varieties. 
    The results were evaluated using analysis of variance, while correlations between the variables were detected using regression analysis.
    The effect of the tested factors on the grain yield was significant in the three-factorial maize experiment despite the annual fluctuations, reflected in extremely variable environmental means. During the given period the effect of N fertilisation surpassed that of the sowing date and the genotype. Regression analysis on the N responses for various sowing dates showed that maize sown in the middle 10 days of April gave the highest yield, but the N rates required to achieve maximum values declined as sowing was delayed. 
    In the very wet year, the yield of durum wheat was influenced to the greatest extent by the plant protection treatments, while N supplies and the choice of variety were of approximately the same importance.  In the favourable year the yielding ability was determined by topdressing and the importance of plant protection dropped to half,  while no  significant difference could be detected between the tested varieties. According to the results of regression analysis, the positive effect of plant protection could not be substituted by an increase in the N rate in either year. The achievement of higher yields was only possible by a joint intensification of plant protection and N fertilisation. Nevertheless, the use of more efficient chemicals led to a slightly, though not significantly, higher yield, with a lower N requirement.