2002 * XIII * 1

V. Geherman.  
  Kultuurrohumaa mulla toitainete sisaldus, botaaniline koosseis ja saagikus tava- ning mahetalus 3
Nutritive status of soils, botanical composition and yielding ability of grasslands in conventional and organic farm. The general purpose was to study the productivity of organic grasslands and compare this with productivity in the same or similar climatic and pedologic conditions situated conventional farm. The investigation based on field experiments that were carried out in 4 different regions of Estonia: Saare and Lääne (West), Harju (North) and Võru (South-East) county in 2001. In current research work the botanical composition, the DM-yield of sward, soil pHKCl, and content of organic matter on the 4 research plots of 5m2 were measured. The content of soluble plant nutrients (P, K and Mg, Ca) estimated by AL (ammonium acetate extraction) method. The dominant soil types in farms of West-Estonia were Calcic Cambisols and in North-Estonian farms Calcic Gleysols, in South-East Haplic Podzols types prevailed. The content of organic matter was higher in organic farms (except in Võru county), pH and soil types were the same in compared farm pairs. The content of lactate soluble P and K depended mostly on the location of farms. The low content of P and K in soil was caused by the low content of parent material in soil and also by very low fertilising level used in conventional farm. One of the most important aim in the Estonian grassland husbandry is the use of legume plants as the source of nitrogen and for increase the protein content of forage. Botanical composition of sward did not differ between conventional and organic farms. The average DM yield of the grasslands in the first cut and the total DM yield were by 10–20% higher in conventional farms. The results did not show a large differences between two farm types, because conventional farms with legume-rich grasslands were quite similar to organic farms which used grass-legume mixtures and few mineral fertilisers.

Keywords: grassland, organic farming, botanical composition, DM-yield, plant nutrients

M. Henno, A. Leola.  
  Varutava piima vabade rasvhapete sisaldus ja lipolüüsi mõjutavad tegurid 10
The free fatty acid content of bulk milk and factors affecting lipolysis. This study concentrated on the effect of different groups of milking systems installed at Estonian dairy farms on the free fatty acid (FFA) content of farm bulk milk.

Dairy farms supplying two Estonian dairies were included in this study. Bulk milk samples were taken from August 1999 to June 2000 from all farms (n=32) supplying Dairy I monthly and twice during the period from January 2001 to May 2001 from the largest farms (n=41) supplying Dairy II. Free fatty acid content was determined using the ”copper soap” method (IDF, 1991b). Milking systems used on farms of the Dairy I were divided into eight groups to evaluate the effect on FFA content: I) new milking parlours − installed after 1994; II) old milking parlours; III) old pipeline milking systems with a long milkline − incorrectly installed systems with 1…4 vertical ascents; IV) reconstructed milking systems with a long milkline − old equipment with proper slope and removed vertical ascents; V) new pipeline milking systems installed after 1994; VI) properly installed pipeline milking systems with a short milkline; VII) bucket milking; VIII) bucket milking, milk transport from shed to tank by milkline.

The mean FFA content of the bulk milk from farms studied was 1.09 mM/100 g fat. In 46.6% of farms it exceeded 1.0 and in 11% of farms 2.0 mM/100 g fat. 3.2% of studied milk samples taken from farms of Dairy I (n=308) had an FFA contentl exceeding the generally accepted detection level of rancid flavour for average consumer (>2.0 mM/100 g fat) and 7.7% exceeded the level for trained experts (1.5 mM/100 g fat).

Used milking systems had a significant effect (P<0.001) on the FFA content of raw milk. Bulk milk with the lowest (P<0.001) FFA content (x=0.33 mM/100 g fat, s=0.063) was produced on farms at which new milking parlours had been installed. The mean FFA content of milk produced with reconstructed (IV) pipeline milking systems (x=0,58 mM/100 g fat, s=0.099) was significantly lower than that of milk produced with incorrectly installed systems (III) (x=1.15 mM/100 g fat, s=0.490).

Keywords: raw milk quality, free fatty acids, induced lipolysis, milking systems.

H. Kiiman.  
  Töövõtete analüüs masinlüpsil 24
The analysis of working operations in machine milking. Milk is one of the most important products for human consumption. The modern lactating dairy cow has much higher milk production than calf needs. In many parts of the world the milk is produced from fewer, but higher yielding cows. This is the result of the great genetic breeding programs and the improvements in feeding and management. Consumers and dairy industry prefer milk with a low fat content and higher protein content. The milk, which is synthesised, is stored in the alveolis, milk ducts, udder and teat cistern between milkings. 60…80% of the synthesised milk is stored in alveolis and small milk ducts, while the cistern only contains 20…40%. A good milking technique is of utmost importance and a milker develops a routine that is followed during each milking. Milking is a central part in dairy management to optimise production capacity and milk quality.

Data were collected from three agricultural enterprises. There were 29 milkers in our trials and their working time observations were carried out one day after contol-milking. It was an operational observation of milkers working during which each element of the working process was registered. Correlation analysis was made to find out by continual factors the cows' preparing for milking, delaying in applying the milking unit to the cow, machine stripping, over-milking and how these factors affect somatic cell count in milk. In our trials the dairy cow groups were large, more than 50 cows milked by one milker. The purpose of the trials was to clear up the quality of milkers' work and to find connections between the mistakes made during milking. How the milking routine affects the milk yield, milk quality and udder health.

From these data analysis observed that some milkers did not pay necessary attention to watching the milking machine. There were large differences in over-milking duration from 0 to 141 seconds (table 1). Duration of udder preparation played essential part to the average milk yield per cow. When there was devoted more time to udder preparation for milking, then the average milk yield per cow was higher (r=0,249***, table 3). A significant positive correlation (r=0,359***, table 2) was observed between the delay in application of a milking unit to the cow and machine stripping. In these groups, where milkers not late in applying the milking unit to the cow, there was less somatic cell count (SCC) in one millilitre milk (r=0,203***, table 3). The effect of over-milking on milk somatic cell count was quite large (r=0,509***, table 3). On the basis of the analysis concerning the relationships between working operations done in machine milking, we can conclude, that the milker who observed one regulation of the machine milking observed the other ones as well.

Keywords: somatic cell count (SCC), over-milking, udder preparation, delay, machine stripping.

I. Nõmmisto.  
  Mesilaste tõulisus ja välimiku tunnused Eestis 29
The raciality and external features of bees in Estonia. The Italian (Apis mellifera ligustica Spin), Carniolan (A. m. carnica Pollm.) and local Nigra (A. m. mellifera L.) bees are kept in Estonia. In 1997…2000 the external features of bees and honey production (kg) were determined in 8 aparies and 37 swarms. The number of investigated bees was 1025. The raciality of bees was determined by the coloration of tergites and the cubital index (%). The cubital index (%) was found as the ratio measurements of neighbour obstructions of cubital obstructions in percents on the first wing. The length of proboscis and wing, the width of wing and tergite, the width and length of the first paw on posterior leg were measured with a gauge. The tarsal index (%) was found as the ratio of width and length of paw in percents. The cubital and tarsal indexix (%) had the greatest variations (V=13.9…20.4%). The length of wing had the smallest variation (V=5.7…8.9%).The Italian bees had longer proboscis by 0.6…0.9 mm (P<0.001), wider wings by 0.6…0.9 mm (P<0.001) and shorter wings by 0.2…0.4 mm (P<0.01…0.001) as the Carniolan, Nigra and crossbreed bees. The Italian bees had the greatest surface of wings, what guaranteed the good flying ability and the greatest tarsal index, what chracterized the ability for carring of the pollen. These properties of the Italian bees conceded good honey production (38 kg) per swarm. The crossbreed bees in first generation (F1) had the longest wings, the other external features did not differ from the other breeds and they produced 43 kg honey per swarm. The Carniolan bees gave 30 kg honey per swarm, the Nigra bees 18 kg and the crossbreed bees F2 only 13 kg. The correlations between external features there were weak(r=–0.018…0.375). The Italian and Carniolan bees and crosses F1 of them are prospective in Estonia.

Keywords: bee, race, raciality, honey production, wings, tergite, proboscis, paw.

U. Tamm, S. Tamm, T. Valgus.  
  Külviaasta punase ristiku saak ja toiteväärtus segus kõrrelistega 36
The sowing year’s harvest and nutritive value of red clover mixed with grasses. The yield of red clover remains usually modest during the sowing year. Respective forage has a low dry matter content, a high protein content and a high nutritive value. The yield of red clover may increase by adding rapidly growing grasses to the seed mixtures, its mixtures facilitate preventing lodging and reduce harvesting losses.

The current study is based on the results of experiments carried out in Juuliku in 2000 and in Olustvere in 2001 according to the identical scheme. Red clover’s pure stand was compared to various mixed sowings. The mixed sowings were composed by adding the following grasses to pure red clover (sowing norm 15 kg ha-1) annual ryegrass ‘Varpe’ (15 kg ha-1), Italian ryegrass ‘Ajax’ (15 kg ha-1), timothy ‘Goliath’ (5 kg ha-1), and smooth bromegrass ‘Lincoln’ (20 kg ha-1). Two cuts were taken during the sowing year.

The added annual ryegrass developed the fastest. It constituted 37…41% of the harvest of the first cut and 17…20% of the harvest of the second cut. Italian ryegrass constituted 36…40% of the harvests of the first and the second cut, timothy and smooth bromegrass each 15…30%.

The total DM yield of mixtures varied from 4.9 to 6.4 t ha-1. The addition of annual ryegrass to a seed mixture resulted in 26…32% higher yield than that of red clover’s pure stand. The respective figure for Italian ryegrass was 16…30%, for smooth bromegrass 20…25%, and for timothy 13…25%. The increase of the yield had a significant effect in the first cut, the yields of the second cut did not differ significantly.

Adding grasses to the seed mixtures reduced protein content of crops. The crude fibre content in DM of the mixed sowings remained mostly below 26% in sowing year. This is in accordance with the forage requirements. This figure was exceeded (29…30%) in the first cut of annual ryegrass and smooth bromegrass mixtures.

The average metabolizable energy content was 10.6 MJ kg-1 in red clover pure stand. It decreased with the addition of grasses and was 10.4 MJ kg-1 in timothy mixture, 10.0 MJ kg-1 in Italian ryegrass mixture and smooth bromegrass mixture, and 9.8 MJ kg-1 in annual ryegrass. The grasses also reduced the metabolizable protein content of forage. The protein balance value was high in red clover pure stand (41 g kg-1), but became more favourable in the mixture with grasses (12…20 g kg-1).

Keywords: red clover, seed mixture, forage, dry matter, crude protein, crude fibre, metabolizable energy, protein balance value.

A. Toomsoo, E. Leedu.  
  Hydro Eesti kompleksväetise efektiivsusest kartuli väetamisel sõltuvalt orgaanilise väetise foonist 42
On the effect of combined fertilisers HYDRO on the yield of potato depending of the background of organic manure. The effect of different norms of the combined fertiliser HYDROCOMPLEX Partner (12:11:18) on the yield of potato ‘Anti’ against different backgrounds of organic manure was studied in a long-term (established in 1989) field experiment. Five different rates of mineral nitrogen (0, 40, 80, 120 and 160 kg N per ha) were used against three backgrounds of organic manure (without, cattle dung with litter, straw).

Weather conditions in the growing season during three years were quite different. The year 1999 was dry and hot, but 2000 was rainy and cold. The year 2001 was hot and rich in rainfall.

On the basis of the results of the three experimental years (1999…2001) it is possible to make the following conclusions:

  • The yield of potato ‘Anti’ was stable during three experiment years, depending on fertilisation rather than on the experiment year (weather conditions).
  • Economically optimum nitrogen rate for potato, depended on the sale prices of potato and mineral fertiliser and of the background of organic manure, was 95…120 kg nitrogen per hectare (792…1000 kg/ha of the combined fertiliser Hydro).
  • In a rainy growing season (as in 2000) it is very important to use chemical control of the potato late blight pathogen (phytophthora infestans).

Keywords: Combined fertilisers, yield, effect of fertilisation, potato.

A. Tsahkna.  
  Eesti Sordilehe kartulisordid Jõgeva Sordiaretuse Instituudi katsetes 47
Potato varieties of Estonian Official Variety List in trials of Jõgeva Plant Breeding Institute. Due to the different conditions and requirements in various locations, many potato varieties exist all over the world. These varieties correspond with the different purposes for which the crop is grown, with the different tastes and preferences of the people and with the different environments in which the crops are grown. Some varieties can be grown in many places and have a wide range of usability; others are meant for very specific purposes or for specific environmental conditions. Apart from production capacity, an important varietal characteristic is the resistance to pests and diseases. Breeding work is constantly going on the developing of new varieties, combining high yield and other favorable characteristics with new or improved resistance to all kinds of pathogens.

Only varieties listed on the Estonian Official Variety List are permitted to grow for the purpose of seed selling. This paper is dealing with description of all the listed varieties during 1999…2001 as potato growers have lack of information how foreign varieties behave in local conditions. Most of the listed varieties have only variety description. The most important characteristics as yielding capacity, starch content, resistance to late bligh and tuber rots have been tested in this study.

Early varieties – the highest yielding had the variety ‘Impala’, followed by ‘Latona’, ‘Berber’, ‘Carlita’. The lowest yielding had ‘Fresco’ and ‘Romina’. Medium varieties – foreign variety ‘Folva’ and local new variety ‘Piret’ exceeded others by yield. ‘Piret’ had also the highest starch content. The lowest starch content had the variety ‘Helena’. Late and medium late varieties – the highest yield had the local varieties ‘Anti’, ‘Juku’, ‘Ando’ and Danish variety ‘Oleva’, lower yielding ‘Saturna’, ‘Van Gogh’ and ‘Vigri’.

From the trial data can be concluded that the most of the early varieties are relatively sensitive to the late blight. Varieties ‘Berber’, ‘Romina’ and ‘Aminca’ did get infection earlier than others. Early varieties are also sensitive to tuber rots. Relatively good resistance to late blight had the variety ‘Anti’, ‘Ando’, ‘Juku’, ‘Jõgeva kollane’, ‘Mats’, ‘Sarme’ ‘Piret’ and foreign variety ‘Procura’. The most sensitive ones were ‘Vigri’, ‘Van Gogh’ and ‘Saturna’. Sensitive to tuber rots were ‘Jõgeva kollane’ and ‘Van Gogh’.

Keywords: Official Variety List, potato variety, yield, starch content, late blight, tuber rots.

H. Jänes, A. Pae.  
  Ülevaade maguskirsipuu kloonalustest 54
An overview of sweet cherry clonal rootstocks. For many years in many cherry growing districts the most widespread rootstocks have been mazzard (P. avium) and mahaleb (P. mahaleb) seedlings of high vigour and late bearing time. Mahaleb has been the most widespread seedling rootstock also in Estonia. Sweet cherry growers would prefere in their orchards dwarf on semidwarf trees which are productive with good fruit quality, easily harvested and early fruiting. The rootstocks must have good graft compatibility with many cultivars and to be easily propagated. Up to present many new rootstocks have been introduced from various breeding programs over the world. The most clonal rootstocks are the clones of Prunus hybrids. From East Malling Experimental Station ‘Colt’ and F12/1 now very widespread rootstocks. ‘Colt’ has a good graft compatibility with many cultivars but is considered to be not sufficiently winterhardy. ‘Charger’ also comes from East Malling. In Germany, at the University of Giessen crosses of different Prunus forms have been carried out and clones of ‘Gisela’ were released. At the University of Weihenstepan types of P. cerasus were selected. At the research station in Gembloux, Belgium, three interesting rootstocks ‘Inmil’, ‘Damil’ and ‘Camil’ were selected. ‘Inra SL 64’and ‘Tabel Edabriz’ are from France. In USA rootstocks ‘Maxma Delbard 14’ and ‘Brokforest’ are the most known, both originated in Oregon. In Russia on the principle new genetical base by interspecific hybridization (P. cerasus × C. maakcii) many interesting clonal rootstocks were bred. These rootstocks include in their genome gene A which is able to control the resistance to coccomycosis. From 1999 VP-1, ‘Rubin’, OVP-2 and OVP-3 are officially recommended as sweet cherry rootstocks for Russian Federation. The perspective rootstocks are V-2-180, V-2-230 and V-5-88.

Keywords: sweet cherry, Prunus hybrids, dwarfing growth, clonal rootstocks.

J. Kasesalu.  
  Kalade haiguste uurimisest Eestis aastani 1940 60
About investigations of fish diseases in Estonia until 1940. The first announcements about fish parasites in Estonia go back to 150 years when Karl Eduard Eichwald described the findings of fish leech – Piscicola geometra – on body surface and gills of several fish species in Gulf of Finland near Tallinn. In the eighties of XIX century Max Braun, the professor of zoology at Tartu University, investigated invasion of predatory fishes by the juvenile stadiums of the broad tapeworm Diphyllobothrium latum in several water bodies around Tartu and revealed first time in the world the developmental cycle of this parasite. The most thorough investigations in XX century were carried out by Guido Schneider (the Gulf of Kihelkonna, the Lake of Ülemiste, the Lake of Võrtsjärv) and Villem Voore (the Lake of Peipus, the Lake of Saadjärv, the Lakes of Õisu and Pangodi and several lesser water bodies). By the year of 1940, 65 species of fish parasites in Estonia were described.

Key words: fish parasites, fish diseases investigators.