1999 * X * 4

M. Karelson.  
  Natural rural life ideologist of the Republic of Estonia 233
M. Karelson.  
  On relationship between power and landed property in Estonian agriculture 241
J. Kuum.  
  Ancient Estonians’ faith and agriculture 256
Ancient Estonians’ faith and agriculture. The ancient Estonians’ faith and world outlook is characterized by animistic treatment of nature which generally prevailed up to the 13th century and partly even longer until Christianity, forced upon the local people, finished it.

Agriculture started to develop here about 2000 B.C. Belief in nature, known as Taara, was formed on the basis of ancient Estonians’ tenet in 1920-ies.

P. Elias.  
  Thermization as pretreatment of milk on cheesemaking 261
Thermization as Pretreatment of Milk on Cheesemaking. The effect of thermization on bacteriological properties of milk and quality of Emmental cheese was studied.

Double thermo-treating was used in the treatment of milk with high total count bacteria (average 2.9±0,7 mil. cfu/ml).

Thermization (65.4±1.0 °C; 20–25 s.) as the first low-temperature thermo-treating did not replace pasteurization of milk and this will be used before the reservation or pasteuriza-tion of cheesemilk. Thermization reduced the total bacterial count of raw milk and this will be used before reservation or pasteurization of cheesemilk. Thermization reduced the total bacterial count of raw milk by 83% and in the milk remained 2.6 times more bacteria than on pasteurization (71.6±1.0 °C; 20–25 s.).

Pasteurization (71.6±1.0 °C; 20–25 s.) of the thermized milk after ripening reduced the count of aerobic bacteria spores, propionic acid bacteria and mesophilic lactobacill, but it did not reduce the count of anaerobic lactate fermenting bacteria spores.

Practical reducing of the aerobic spore forming bacteria takes place only on the pas-teurization of the thermized and ripened milk, because the vegetative cells of bacteria which grew out of spores on ripening were destroyed during pasteurization. In pasteurized and ripened milk they retained and were more active than before.

The double thermo-treatment of milk on cheesemaking did not cause essential differences to the general development of bacteria. Differences were in counts of single species on difference stages of cheesemaking. When the double thermo-treatment of milk was used, the count of lactococci was essentially lower in cheesemaking processes. Mesophilic lactobacilli and spores of mesophilic aerobic bacteria were lower still in 3 months old cheeses, than in cheeses which were made from pasteurized and ripened milk.

Thermization together with pasteurization did not influence the cheesemaking process, but reduced number of contamination microbes, increased essentially the part of starter cultures. It improved the organoleptic properties of cheeses and increased their quality. We had no earlier data about cheesemilk thermization in Estonia. Therefore the double thermo-treatment is useful to use, when the total count of bacteria in raw milk is high as not on making high cooking temperature cheeses, as on low cooking temperature cheeses too.

Keywords: milk, thermization, pasteurization, contamination microbes, quality of cheese

K. Kask.  
  Tree fruit and bush fruit cultivars of Estonian origin and their value 268
Tree fruit and bush fruit cultivars of Estonian origin and their value. The first Estonian apple cultivars ‘Suislepp’ and ‘Tallinna pirnõun’ were introduced in the 18th century. In the 19th century, two apple cultivars were introduced in addition. The other Estonian tree fruit and small fruit cultivars has been bred in the 20th century, mostly from the thirties and fourties. The whole number of Estonian cultivars (1998) is 117, including 35 apple, 10 pear, 24 plum, 4 sour cherry, 3 sweet cherry, 7 strawberry, 4 raspberry, 2 red currant, 3 white currant, 10 black currant, 7 gooseberry, 6 cranberry (Vaccinium oxycoccus), 1 lingonberry, and 1 cloudberry cultivar. Altogether 57 cultivars are originated in the Polli Horticultural Institute, 10 – in the Jõgeva Plant Breeding Institute, 34 are bred by amateur breeders (including the 6 cranberry cultivars in the Nigula Nature Reserve) and 16 are landraces.

There are many selections in the breeding in progress. Especially numerous selections are in sweet cherry which were planted (1998) into second test at the Rõhu state experimental farm. Some apple and plum selections have shown a good perspective for growing in Latvia as well.

Estonian cultivars have great importance for fruit and berry producing. Thus, in the list of the recommended for growing in Estonia cultivars (from 1998) of Estonian origin are: 50% apple cultivars (including 21% of Polli’s) origin, 100% pear cultivars, 59% plum cultivars (41% are Polli’s), 17% sour cherry, 60% sweet cherry (all from Polli), 38% raspberry (all from Polli), 20% black currant (including 1 Polli’s cultivar), and 100% cranberry cultivars.

In Latvia, 4 apple, 1 pear, 2 plum, and 2 sweet cherry cultivars of Estonian origin are included into the list of recommended for growing in Latvian orchards. One apple cultivar, ‘Tellissaare’ is recommended for growing also in Lithuania and Belarus. The most widely cultivated Estonian apple cultivar is ‘Suislepp’: from the Baltic to Kazakhstan and the eastern coastal areas of Black Sea.

‘Suislepp’ is also the most valuable parent cultivar in apple breeding among the Esto-nian cultivars. There are at least 16 cultivars which pedigree consists ‘Suislepp’. They are bred in Estonia, Latvia, Kazakhstan and Russia (Krasnodar district and Michurinsk).

Not one bush fruit cultivar of Estonian origin is widely distributed in other countries.

R. Kask, H. Samel.  
  Changes in the typical sold-calcareous and half-bog soddy soils properties of native grasslands due to their development and use as arable lands 276
Changes in the typical sod-calcareous and half-bog soddy soils properties of native grasslands due to their development and use as arable lands. The development of a native grassland 1962 and its use as arable land bring about considerable changes in the soil properties. In the case of similar use, changes are the most conspicuous in peaty-soddy gley soils and peaty gley soils.

After the first year (1963) in use (growing barley) a considerable decrease was observed in the content of organic matter and the C:N ratio of the soils. During the use of the plots as field pasture (1966-1977) all soils demonstrated a considerable increase of the organic matter and nitrogen contents. The following period (1978-1997) when the main crop culti-vated was grain brought a constant decrease of the organic matter and nitrogen contents. In 1997 the proportion of the organic matter (1.72 Corg) in the Aorg horizon as compared to its initial level measured in 1962, was 91% for the typical sod-calcareous soil, 93% for the gleyed sod-calcareous soil, 85% for the soddy gley soil, 73% for the peaty-soddy gley soil, and 61% for the peaty gley soil. During the 35 years of observation the average annual decrease of the content of organic matter in the above soils was 0.8, 0.4, 0.9, 2.2, and 5.3 t/ha, respectively.

The decrease of the C:N ratio during the observation period indicates that the organic matter changes in an agrochemically positive direction. After the 35 years of tilling the studied soils had their C:N ratio close to the optimum (~10).

The intensive use of mineral fertilizers (282 kg of N, P2O5 and K2O was spent on an average hectar of arable land during the period of 1967-1987) increased the content of lactate soluble P2O5 and K2O in all soils. Since 1993 when the intensive fertilization ended, the level of those nutrient elements has been falling. By 1997 the level of K2O had dropped below that of 1985. In the case of insufficient fertilization the shortage of potassium in plants shows sooner than that of phosphorus.

Despite extensive use of various fertilizers, incl. nitrogenous ones, the pHKCl level of the soils studied has not dropped, but even increased. This can be explained by the good buffering capacity of the soils due to the presence of CaCO3 in the arable layer.

The bulk density of the studied soils, measured after the harvesting of barley in 1997, was close to the optimum. Consequently, the 35 years of cultivation had left the soils in an agro-physically favourable state.

H. Kärblane, L. Kevvai, J. Kanger.  
  Heavy metal contents of timothy 283
Heavy metal contents of timothy. The content of dangerous heavy metals (Cd, Hg, Pb) and also a few heavy metals that are seen as microelements (Co, Cu, Mo, Mn, Zn) of timothy is characterised by 74 samples collected from field and pastures of Estonia.

Final data of content of heavy metals in timothy characterised the variation and the average values presented on figures 1 and 2. It can be seen that there is always a smaller degree of dangerous heavy metals and microelements in timothy than the maximum allowed grade in Estonia for fodder. Thus, the timothy is not polluted by heavy metals in Estonia.

The content of some microelements (Co, Cu, Mn, and Zn) is lower than the optimal degree, therefore the biological quality of the fodder is lowered also.

Timothy must be fertilized with fertilizers contained Co, Cu, Mn and Zn to obtain the high quality fodder.

V. Pileckas, A. Urbšys, J. Kutra.  
  The Lithuanian technique of bull semen collection and cryopreservation 292
The Lithuanian technique of bull semen collection and cryopreservation. Semen is diluted if spermatozoa motility is not lower than 70% and spermatozoa concentration is no less than 800 million per millilitre. For semen evaluation, plastic bags with the ejakulate are stored in the termostat at 27±1 °C. Good quality semen is diluted in a plastic bag at a ratio of 1:1. 15 to 20 minutes after collection of the last ejaculate, semen is diluted for the second time. The finitial concentration should be no less than 15 million of motile spermatozoa per dose after the thawing. After the second dilution the semen is packaged in sterile plastic straws. Thereafter then semen should be cooled at 4±2 °C for 180 to 240 minutes. Semen is frozen in a biocontainer with a special equipment – a cooper freezing net. The temperature should be maintained at –150±30°C depending on the individual characteristics of bull semen. The freezing cycle should last for 8 minutes incuding temperature stabilization.

Keywords: bull, semen, collection, dilution, cooling, freezing.