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• Clusteranalysis as a swine farm qualifying method

  165-174

  Sándor Kovács

  Péter Balogh

  Views:

  87

  Cluster Analysis is one of the most favorite multivariable statistical methods, which is actually a special type of aggregating method. Observations are clustered by variables belonged to the observations. Our purpose is to create such clusters, in which the elements are the most similar, and between the clusters they are the most variant. For example these clusters could be the qualitative classifications of farms.
  There have been several methods in Cluster Analysis as well as numerous distance measures, which could be used. In this article, we study all of these methods and measures. After we show the theoretical background, we apply the method in a given casestudy to control the qualitative classifications of experts. In this study, we use both the hierarchical and the non-hierarchical method, and also compare them. We would like to attract the attention that the most important problem of the analysis is to determine the optimal of clusters.

• Occurrence and damage of the alfalfa root longhorn beetle (Plagionotus floralis Pallas, 1773) in old alfalfa stands in Hungary

  82-88

  András Bozsik

  Views:

  92

  The alfalfa root longhorn beetle is a pest of small importance in old alfalfa stands. It is rarely cited in the international, national literature, or even mentioned in specialized manuels. Plagionotus floralis is common in Hungary but its population density is low. It is a polyphagous species but it has importance - regarding the references – only in alfalfa. This paper analyses data gained in old alfalfa fields at two different regions of the country (Máriabesnyő, Debrecen). Damage of P. floralis was 56% in the roots of an 8-year-old stand in Máriabesnyő. Lenghts of tunnels were between 3 and 22 cm. In spite of the tunnels the alfalfa plants were viable. There was no root longhorn beetle in the 15-year-old Debrecen stand, however it has been found former in the region. The reason for the important density of P. floralis in Máriabesnyő could be the considerable diversity and covering of flowering weeds around the field. Adults of P. floralis feed on flower pollen and nectar. As to the Debrecen area,weeds were cut regularly, so the edge vegetation was poor. Present conditions (no pest control on alfalfa fields, overuse of old and failing alfalfa stands, many untrained growers) favour the reproduction and possible damage of alfalfa root longhorn beetle. 

• Examination of the chlorophyll content of maize hybrids of different maturity groups at different N fertiliser doses

  159-162

  Péter Ragán

  Views:

  117

  Nitrogen fertilisation is a critical point of maize production. Five hybrids of different maturity dates were examined in a field experiment, three treatments (different application dates) and three basic fertiliser doses (0, 60, 120 kg ha^-1 N) were used. At the 6-leaf-stage of maize, each fertilisation level of the 2nd and 3rd treatment was given 30 kg N ha^-1 fertiliser active ingredient in addition to the basic fertiliser doses with the exception of the control plots and further 30 kg N ha^-1 fertiliser was applied at the 12-leaf-stage. The final fertiliser doses were 0, 90 and 150 kg N ha^-1 in the second treatment and 0, 120 and 180 kg N ha^-1 in the 3rd treatment. The whole amount of the basic fertiliser (ammonium nitrate) was applied in the spring, one month before sowing.

  The relative chlorophyll content of the maize leaves was measured, with a Minolta SPAD-502 measurement device. The measurements were carried out at the 6-leaf growth stage (V6) of maize on the youngest fully developed leaf of the 6^th, 7^th and 8^th plants from the second row of each plot.

  There were significant differences in the SPAD-readings measured at the V6 phenophase of maize between the hybrids (p<0.001) and the fertiliser treatments (p<0.05). The regression analysis did not show any correlation between the SPAD-values and fertilisation.

  The highest significant SPAD-reading and yield were obtained by applying 120 kg ha^-1 N. As a result of the regression analysis performed on yield, it can be concluded that the correlation between fertilisation and yield in the 1^st and 2^nd treatment was moderately close (r=0.439, r=0.480) and it was close in the 3^rd treatment (r=0.513). The correlation between the SPAD-readings and yield was the closes in the 2^nd treatment (r=0.639), while the SPAD-value had a 40.9% influence on yield (p<0.001).

• Genetic diversity of the Hungarian draft horse assessed by mitochondrial DNA

  29-32

  Nikolett Csizmár

  Sándor Mihók

  András Jávor

  Szilvia Kusza

  Views:

  202

  Hungarian draft is a horse breed with a recent mixed ancestry. It was developed in the 1920s by crossing local mares with draught horses imported from France and Belgium. To genetically characterize the breed and to set up the basis for a conservation programme, we have employed a molecular marker: a 256-bp D-loop mitochondrial DNA fragment. We analyzed 124 horses representing Hungarian draft horses to assess the maternal phylogeography of the breed. Sequence analysis of a 256-bp segment revealed a total of 34 haplotypes with thirty-four polymorphic sites. High haplotype and nucleotide diversity values (Hd=0.953±0.001; π=0.024±0.001) were detected. The average number of pairwise differences were k=5.998. This breed counts 800 mares today, and only survive due to breeding programmes, this way each haplotype frequency depends on the extent to which mares are involved into the breeding. The reduced number of surviving maternal lineages emphasizes the importance of establishing a conservation plan for this endangered breed. Due to the revealed 34 polymorphic sites we could presuppose twelve maternal linages, which could be a first step for making a breeding programme.