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  • Investigation of genetic diversity in irradiated maize lines and its relation to hybrid performance
    20-26
    Views:
    152

    Knowledge of genetic diversity among available parental lines is fundamental for successful hybrid maize breeding. The aims of this study were to estimate (1) genetic similarity (GS) and genetic distance (GD) (based on Jaccard index) in four maize inbreed lines; (2) to classify the lines according to their GD and GS; (3) to determine hybrid performance based on GD and heterosis for yield ability in 4x4 full diallel system. We used morphological description and AFLP (amplified fragment length polymorphisms) for estimation genetic polymorphism in four maize inbred lines. We estimated the applicability of genetic similarity in SC and reciproc hybrids for prediction of their performance.
    Three primer combinations were used to obtain AFLP markers, producing 207 bands, 70 of whit were polimorphic. The dendogram based on genetic similarities (GS) and genetic distance (GD) and morphological description separated four inbred lines into well-defined groups. Morphological description just with AFLP analysis showed reliable results. In view of genetic distance, the UDL 1 line and their linear and reciprocal crosses showed significant heterosis effect, which was confirmed by heterosis calculation based on grain yield.

  • 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.

  • Impact of chronic heat stress on digestibility of nutrients and performance of meat type ducks
    51-55
    Views:
    188

    The aim of the study is to determine the effect of vitamin and mineral supplement under permanently high environmental temperature (30±1 °C) on the digestibility of nutrients, performance and furthermore the composition of duck meat in the growing period. A total of four hundred mixed sex 14 days old Cherry Valley type hybrid ducks were used for the study. Two experimental diets were formulated in the study (control and vitamin E, C and zinc supplemented diet). Based on the results the following conclusions were drown: the antioxidant defence system plays an important role in the reduction of heat stress generated lipid peroxidation process. Feed additives which have direct or indirect antioxidant effects can reduce the negative effects of heat stress on the ducks performance and meat composition. Digestibility of nutrients (Dry Matter, Crude Protein, Crude Fat) was not affected by antioxidant supplementation under chronic heat stress (30±1 °C). The performance was affected significantly by Vitamin C and E and zinc supplementation under heat stress (P<0.05). In the treated group the daily weight gain (dWG) increased and the feed conversion ratio (FCR) was improved significantly (P<0.05). The energy and protein conversion was decreased also significantly (P<0.05).

  • Preliminary results of intraspecific sterlet hybrid (Siberian sterlet × sterlet) rearing under intensive conditions
    17-19
    Views:
    116

    Due to early maturation and a small size, sterlet (Acipenserrut-henus) is a very advantageous fish for intensive sturgeon farming with regard to caviar production. According to our previous observations, the growth potential of Siberian sterlet (A.ruthenusmarsiglii) is higher than that of the European one. In our experiment, sterlet and an intraspecific hybrid (Siberian sterlet × sterlet) were tested under intensive tank conditions. During the 8 weeks of the experiment, survival, growth and size heterogeneity were investigated. According to the results, there were no significant differences in survival and growth but the size heterogeneity was higher in the hybrid. It is supposed that, in our trial, the applied water  temperature range (24.0–25.5 °C) was optimal for sterlet, but was probably above the optimal range for the hybrid.

  • 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.