Use of Rapid Light Curves to Evaluate the Plant Photosynthetic Performance
Marek KOVÁR, Katarína OLŠOVSKÁ, Marián BRESTIČ (Slovak Agricultural University, Nitra)
Paper is in English
(2 tab., 6 ill., 30 ref.)
In the experiment with barley plants (Hordeum vulgare L.;
genotype Kompakt) variable photosythetic active radiation
intensities (PPFD) and time exposition of individual PPFD in
the course of photosynthetic light curve were evaluated. Two
basic light curve procedures were used: rapid light curve
(RLC; 10 and 30s intervals) and slow light curve (LC; 1, 3, 5
and 15 min intervals). Significant changes were observed in
actual photochemical efficiency of PSII as well as in linear
electron transport rate. These data were obrained by quenching
analysis. It was found that the 3 min time interval of
irradiation intensity is sufficient for evaluation of in situ
behaviour of barley photosynthetic apparatus. In addition,
this work gives a brief view into the action of photosynthetic
apparatus on the level of electron trapping and optimal
excitation energy use in stress conditions
Key words: photosynthesis, chlorophyll fluorescence, light curve, quenching analysis, water stress, barley
Adress: Marián Brestič, Dept. of Plant Physiology, Slovak Agricutlural University, Tr. A. Hlinku 2, 949 76 Nitra, Slovak Republic
tel.: +421-37-6508 448;
e-mail:Marian.Brestic@uniag.sk
The Content of Macroelements and Microelements in the Above-ground Biomass of Amaranth
Helena GREGOROVÁ (Slovak Agricultural University, Nitra)
Paper is in Slovak
(6 tab., 21 ref.)
The content of mineral elements (P, K, Ca, Mg, Na) and
microelements (Cu, Mn, Zn, Fe, Cd) in the above-ground biomass
of amaranth (Amaranthus hypochondriacus L., the 1008 variety)
and their uptake by the stand were studied. Field trials were
performed in irrigation-free conditions of south-western
Slovakia, at the experimental station of the Slovak
Agricultural University in Nitra - Dolna Malanta. Amaranth was
seeded in two row spacing (0.250 and 0.375 m) and the plants
were tinned to two densities (300 and 400 thousand plants per
hectare). Years were found to influence highly significantly
the content of mineral elements. The effect of stand
organisation (row spacing and density) on the content of
mineral elements was not statistically significant. On an
average of the experimental years 1994-1996, 1 kg of dry
matter of amaranth contained 3.83 g P, 35.18 g K, 18.93 g Ca,
10.45 g Mg, 0.32 g Na, and on an average of 1994-1995 these
values were 19.62 mg Zn, 9.83 mg Cu, 105.48 mg Fe, 48.01 mg
Mn, and 0.03 mg Cd. At an average of experimental years, the
above-ground biomass of amaranth showed an uptake per hectare
of 32.7 kg P, 311.5 kg K, 177.8 kg Ca, 92.6 kg Mg, 2.9 kg Na,
178 g Zn, 89 g Cu, 938 g Fe, 455 g Mn, and 0.32 g Cd
Key words: Amaranthus hypochondriacus L., row spacing, plant density, macroelements, microelements, uptake by stand of mineral elements
Adress: doc. Ing. Helena Gregorová, CSc., Katedra krmovinárstva, Agronomická fakulta, Slovenská poľnohospodárska univerzita v Nitre, Tr. A. Hlinku 2, 949 76 Nitra, tel.:+421-37-650 8237
The Influence of Soil Sample Processing Time on the Determined Content of N-NH4+, N-NO3- and Nan
Peter KOVÁČIK, Anton ZAUJEC (Slovak Agricultural University, Nitra)
Paper is in Slovak
(6 tab., 21 ref.)
The influence of natural drying time on Nan content soil was
investigated by N-NH4+ and N-NO3 content determination in
three time intervals (3, 24 and 48 hours after sampling,
respectively). The relationship among determined Nan values
and aboveground and underground biomass of the model crop
(radish) was examinated by linear regression analysis. The
result indicated that prolonging a drying time increased Nan
content in soil. the lowest amounts were determined in fresh
soil (3 hours aftere sampling) and the highest ones in dry
soil (48 hours after sampling). Average difference in Nan
contents between fresh and dry soil was as high as 76.6%.
Correlations between an amount of model crop biomass and Nan
concentrations in semi-dry and dry soil were closer in
comparison with those of Nan determined in fresh soil. A dry
or semi-dry sample was found to be more suitable than freshly
taken soil sample for the Nan content determination to
calculate nitrogenous fertilizer rates for radish (model crop)
Key words: inorganic nitrogen, soil sample processing
Adress: Ing. Peter Kováčik, CSc., Katedra agrochémie a výživy rastlín, Agronomická fakulta, Slovenská poľnohospodárska univerzita, tr. A. Hlinku 2, 949 76 Nitra, Slovak Republic
tel.: +421-37-650 8381; e-mail:Peter.Kovacik@uniag.sk
An Investigation of Importance of Some Behaviour Indicators in Pigs of the Large White and Belgian Landrace Breeds
Ľubomík KOVÁČ, Jozef MLYNEK, Ivan LIDAY, Martin NOVACKÝ, Mária UŽÁKOVÁ, Anna KUBINOVÁ, Miroslav KUBINA (Slovak Agricultural University, Nitra)
Paper is in English
(2 tab., 5 ill., 18 ref.)
Individual habituation process and CNS excitability in a new
environment of the test chamber were investigated in four
20-min habituation tests in 32 pigs of the Large White (n=16)
and Belgian Landrace (n=16) breeds. Each animal was tested at
30 and 90 kg live weight in morning and afternoon tests. It
has been proved that motor activity and voice manifestations
of pigs are significant indicators of inborn behaviour and
show both the short-term stability and the long-term stability
of excitation levels in 20-min habituation tests. The results
obtained indicated the habituation dynamism of motor activity
indicator for both weight categories, 30 kg animals being more
active. Although no significant differences between the two
breeds were detected in the dynamism of motor activity, Large
White pigs were more active than Belgian Landrace pigs, in
both weight categories. The process of voice manifestation
habituation brought different results from those of motor
activity indicator, Both the process of motor activity
habituation and the frequency of voice manifestation were
higher in Large White pigs. On the other hand, no
characteristic habituation process was observed in voice
manifestations, Proceeding from the above results we can state
that there is statistically significant correlation between
motor activity and voice manifestations, Statistically
significant correlation was also found in voice
manifestations, not onlz between morning tests and afternoon
tests but also within morning and afternoon tests,
respectively
Key words: pig habituation, CNS excitability, ethology, breed differences
Adress: prof. Ing. Ľubomír Kováč, DrSc., Katedra špeciálnej zootechniky, Agronomická fakulta, Slovenská poľnohospodárska univerzita, Tr. A. Hlinku 2, 949 76 Nitra, Slovak Republic
tel.: +421-37-650 8146; e-mail:Lubomir.Kovac@uniag.sk
Prediction of Expected Genetic Progress of Growth Intensity and Meat Production of Pinzgau Bulls
Radovan KASARDA, Ondrej KADLEČÍK (Slovak Agricultural University, Nitra)
Paper is in Slovak
(1 tab., 4 ill., 13 ref.)
A genetic progress and trends in average daily and net weight
gains in Pinzgau bulls were estimated by 2010 using the gene
flow method. The results from testing young sires for meat
production in 1989 and 1990 were used as input data. The
average weight increase of bulls was 1070 g (850-1231 g/day)
and net gain was 579 g/day on average (502-613 g/day). Average
annual genetic progress in growth rate was 1.63 g, the
estimated values ranging from 1.35 g/day in year 8 of the
breeding program to 3.55 g/day in year 6, and in net gain it
was 0.64 g/day, at an interval of 0.49 to 1.29 g/day. Genetic
trend of both characteristics was positive. After 20 years of
running the breeding program, a genetic improvement of 20 and
8 g, respectively is predicted for daily growth rate and net
gain. In 2010, the genetic gain of growth rate and net gain in
Pinzgau bulls is expected to achieve 1090 and 587 g/day,
respectively
Key words: Pinzgau cattle, growth intensity, meat production, genetic progress, gene flow
Adress: Ing. Radovan Kasarda, Katedra genetiky a plemenárskej biológie, Agronomická fakulta, Slovenská poľnohospodárska univerzita, Tr. A. Hlinku 2, 949 76 Nitra
tel.: +421-37-650 8292