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  • Comparison of RAPD and AFLP Analysis in Some Maize (Zea mays L.) Lines and Hybrids
    3-7
    Views:
    88

    The use of molecular markers to enhance plant breeding efforts is being widely studied. DNA-based fingerprinting technologies (RAPD and AFLP) have proven useful in genetic similarity studies. We estimated different maize (Zea mays L.) inbred lines and hybrids originated from mutant ones based on their genetic differences.
    We carried out RAPD analysis with different primers and the 707 (CCCAACACCC) and 792 (CAACCCACAC) primers with 50% similarities provided quite good DNA fragments. By applying the DNA based-AFLP technique, we had very dense DNA fingerprinting. We differentiated 15-32 polymorphic bands, the highest number of bands were found in P-T/H-CA (32). AFLP seems to be the more efficient method of comparing genetic similarities/differences among different genotypes.

  • Fruit melanotic ringspot (FMRS) – a disease of resistant Capsicum genotypes infected with Tomato spotted wilt virus (TSWV) on the fruits
    64-69
    Views:
    64

    Etiology of pepper fruit melanotic ringspot (FMRS) disease (Salamon, 2009) was studied on fruit samples collected in forced pepper populations. It was noticed that in spite of heavy thrips (Frankliniella occidentalis) infestations and of TSWV epidemy detected in the forcing houses, FMRS occurred only in plants having healthy foliage. Symptomatological surveys strongly suggested that FMRS appeared exclusively in specific pepper genotypes. The size of melanotic ringspots has been observed to grow at room temperature during postripening of diseased fruits. A mechanically transmitted plant virus was isolated from symptomatic parts of 9 white pepper fruits affected by FMRS. On test plants each of the virus isolates caused systemic symptoms characteristic to TSWV. Using cDNA/PCR technique and TSWV N-gene specific primers a ca. 300 bp long DNA fragment has been amplified from total nucleic acid extracted from symptomatic tissues but never from asymptomatic parts of the fruits showing FMRS. Plant progenies grown from seeds of FMRS diseased fruits segregated in respect of resistance and/or susceptibility to TSWV infection. TSWV was also detected in and isolated from three fruits showed non-melanotic yellow rings (one of them was infected with a tobamovirus, too). Seedlings derived from these fruits proved to be susceptible to TSWV. Based on the above results we could conclude that the FMRS disease developed on fruits of “cecei” type white peppers that carry a TSWV resistance gene, most likely the Tsw gene in heterozygous form. These fruits were infected with thrips transmitted TSWV and FRMS appeared as a hypersentive reaction (HR) manifested in fruits.

  • The Fattening and Slaughtering Examination at the Hungarian Racka Sheep
    37-42
    Views:
    88

    Fattening and slaughtering characteristics of both types (black and white) of the Hungarian racka sheep were investigated at the site of the National Institute for Agricultural Quality Control in Atkár. The Hungarian merino, the dairy cigaja and the British milksheep were applied as control groups. 10 animals were examined from both sexes in each genotype. The examination was carried out according to the principles set in the Codex for sheep breeding. During the test acute diarrhoea occurred in each control group. However, only few lambs were excluded from the test from the British milksheep and the Hungarian merino groups because of significant changes in their condition. Consequently, the results obtained were not significantly influenced. No symptoms of any illness could be recognised in the Hungarian racka sheep, though. The significance of the difference between the average of the examined groups were checked by T-tests.
    Daily gain was significantly less compared to the control groups, except for the white racka males. The lambs starving for 24 hours before slaughtering weighed 25.3-30.0 kgs on average. The black and white racka females weighed the least while the Hungarian merino females weighed the most. The quantity of abdominal and kidney fat was significant in the case of our native females. The quantity of abdominal fat was significantly bigger compared to each control group. On comparing the investigated groups it turned out that the white racka males had the biggest skin weight while the white Hungarian racka females had the smallest, that is the two extremes were recognised in the same colour (white) of one bred. On qualifying the slaughtered animals females had better results than males in each bred; the racka sheep were better than the dairy cigaja but were worse than the Hungarian merino and British sheep groups.
    The huge differences in the carcasses of the groups were seen clearly when chopping. Examining the leg, it was noticed that the native groups proved to be smaller than the control groups, except for the black racka males. As for the short loin, the Hungarian racka and the Hungarian merino sheep proved to be the best, whereas the dairy cigaja and the British milk males had much smaller ones. The results gained when investigating the rack were similar to those of the short loin. As far as the rib and shoulder are concerned, the black racka females and the dairy cigaja females had the worst results. After chopping, the right side was also boned in every group. The small proportion of bone in the case of racka sheep was easily noticeable that resulted in the fact that the white racka females had the highest quantity of short loin compared to the other groups. When examining the back quarter, the bone proportions of the 4 racka groups proved to be significantly less than those of the control groups but it was not true for the meat proportions. As for the front quarter meat, the racka males were prominent in the great shoulder meat and in the small proportion of bone. The quantity of the first quarter bone was the least in the case of racka sheep and was the biggest for dairy cigajas. This difference proved to be significant in most cases.
    In short, the Hungarian racka groups had the best results in meat quantity, which was especially significant compared to the dairy cigaja sheep. However, the quantity of external fat increased.

  • Results of fast neutron induced mutations in M1 and M2 generations of sorghum (Sorghum bicolour)
    49-54
    Views:
    78

    Due to climatic barriers, the genetic variability of Sorghum varieties decreases away from the gene centre, therefore hybrids cultivated in Hungary are restricted to a relatively limited genetic basis. This limited genetic basis results in a lower rate of genetic improvement, so the genetic basis of cytoplasm factors are to be extended. We enhanced the diversity of primary materials by fast neutron treatment. As a result of this treatment we detected sterile, deformed specimens with double panicles in the stock treated with a dose of 12.5 Gy in the M1 generation. Agronomically useful
    specimens were found in the stock treated with 10 Gy and 7.5 Gy doses, where the leaf area index (LAI) and Harvest- index gave higher values than those of the control group. In the stock treated with 5 Gy dose, variations were less significant. In the reseeded M2 generation we detected albino specimens with extreme chlorophyll defects in the 10 Gy Zádor stock.

  • 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.