1997 * VIII * 2

J. Kuum.  
  Home husbandry in Estonia 141
O. Saveli.  
  Economy of milk production in Estonia 151
M. Agur.  
  The resistance analysis of potato varieties to potato virus X isolates (KVX17, KVXOlev, KVXSulev) infection 157
The resistance analysis of potato varieties to potato virus X isolates (KVX17, KVXOlev, KVXSulev) infection. The complete resistance analyses of potato varieties ‘Ants’, ‘Berber’, ‘Lazunak’, ‘Prigozii’, ‘Procura’, ‘Sante’, ‘Sarme’, ‘Timate’ and ‘Varane kollane’ to three KVX isolates were carried out. The degree of susceptibility/resistance, the virus biosynthesis intensity and symptoms of infection in KVX17, KVXOlev and KVXSulev inoculated plants (first year) and in the plants of their tuber reproduction (second year) have been determined in order to compare the reaction of potato varieties to the infection with different isolates of the same virus. The varieties ‘Timate’, ‘Sante’ and ‘Sarme’ were nonsusceptible (immune) and variety ‘Varane kollane’ high (100 %) susceptible to all three KVX isolates tested. In five varieties (‘Ants’, ‘Berber’, ‘Lazunak’, ‘Prigozii’, ‘Procura’) the degree of susceptibility/resistance, virus biosynthesis intensity and/or symptoms to PVX isolates infection differed depending not only on the variety but also on virus isolate. In all combinations of variety and virus isolate the characteristics determined were higher in the plants of second generation than in inoculated ones.

The varieties nonsusceptible to all three KVX isolates (‘Timate’, ‘Sarme’, ‘Sante’) are prospective as the initial material for potato breeding to this virus resistance. In addition it appears reasonable to assume that the variety – virus isolate combinations with the degree of susceptibility less than 100 % may be used for the clone selection and reciprocal analyses to get virus resistant material. The necessarity to use more than one isolate of the virus for the evaluation of the potato variety virus resistance was pointed out (accented).

A. Bender.  
  Polymorphism of fertility and self-fertility of alfalfa varieties ‘Jõgeva 118’ and ‘Ellerslie I’ and the opportunities for use the plants selected from these populations as initial material for plant breeding to breed partially self-pollinative varieties and hybrid varieties 162
Polymorphism of fertility and self-fertility of alfalfa varieties ‘Jõgeva 118’ and ‘Ellerslie I’ and the opportunities for use the plants selected from these populations as initial material for plant breeding to breed partially self-pollinative varieties and hybrid varieties. Fertilization of the flowers on free pollination and self-pollination has been investigated with 135 varieties of Medicago sativa L., M. varia Martyn., M. falcata L. and M. borealis Grossh. in the open field trials at Jõgeva during 1983…1990. Obtained experimental data enable to clarify the polymorphism of these characters in the populations and to find initial material for different breeding aims.

Among the investigated varieties the most notable by seed yield, level of fertility and self-fertility of the flowers were the varieties of M. varia ‘Jõgeva 118’ (Estonia) and ‘Ellerslie I’ (Canada).

On the free pollination of the flowers (experimental variant K) the populations of both varieties mainly consisted of partially fertile (Fk=0.1…29.9 %) and sterile (Fk=0 %) plants. These two groups of plants accounted for 70.9 % from the population variety ‘Jõgeva 118’ and 84.9 % from the population of variety ‘Ellerslie I’. The plants with intermediate (Fk=30.0…49.9 %) and above intermediate (Fk=50.0…79.9 %) fertility occurred considerably less in the populations (Table 2, Figure 1). Generally the following regularity was valid: the higher the class of fertility (or self-fertility), the less plants belonged to that class.

On the base of the figures of self-fertility (experimental variant ATI) even more plants belonged to the class of partially self-fertile (IFk=0.1…29.9 %) and self-sterile (IFk=0 %) plants – 88.1 % on the variety ‘Ellerslie I’ and 93.0 % on the variety ‘Jõgeva 118’. It was still possible to find the plants with intermediate (IFk=30.0…49.9 %), above intermediate (IFk=50.0…79.9 %) and even high self-fertility (IFk=80.0…100 %) from both populations (Table 3, Figure 2). Hence the plants with very different level of self-fertility were found in the populations of these varieties. The clones of these plants can be used as initial material in breeding process, conducted on different methods, to create partially self-pollinative varieties.

Artificial tripping of the flowers (experimental variants KT and KTI) promoted the fertili-zation of the flowers of investigated varieties. Effect of this treatment was significantly superior with variety ‘Jõgeva 118’ (Tables 2 and 3, Figures 1 and 2).

From both populations the plants were found which formed the pods only with free pollina-tion. In the population of variety ‘Ellerslie I’ 7 such plants occurred (with fertility in the control variant Fk=1.3…25.0 %) and in the population of variety ‘Jõgeva 118’ 5 plants (with fertility in the control variant Fk=2.2…36.3 %). These plants could be completely sterile, hence interesting material in the breeding of hybrid varieties. As F1 hybrid varieties based on the heterosis effect are not bred at Jõgeva, the reasons and stability of self-sterility of these plants were not clarified in further research.

P. Lättemäe, P. Rausberg.  
  The effect of wilting and sodium benzoate based additive on silage quality of grass and legume-grass mixture crop 172
The effect of wilting and sodium benzoate based additive on silage quality of grass and legume-grass mixture crop. The aim of the present investigation was to improve silage quality by using silage additive, based on sodium benzoate and hexamine or by wilting of the herbage.

Six forage stands were used in this study. Four stands consisted of pure grasses and two stands were legume-grass mixtures composed as follows: cocksfoot, bromegrass, reed canarygrass, timothy, lucerne-grass mixture and white clover-grass mixture. For each forage stand three cutting frequencies were applied, i.e. 4-, 3- and 2-cuts. The first three consecutive cuts of 4-cuts and from the first two cuts of 3-cut treatments were ensiled in 3 litre glass silos for 100-120 days. The harvest times and herbage development stages varied but most of the grasses were at the leaf stage.

The following silage treatments were applied: (a) untreated, (b) benzoate/hexamine (Superben) treated at an active matter of 1600/700 g ton-1 fresh matter (FM) and (c) crop wilted in the field for 22-24 hours, without September.

The quality of the untreated silage was satisfactory but a poor fermentation was obtained, reflected in high pH values, in low levels of lactic acid and in relatively high concentrations of butyric acid. Application of Superben to direct cut herbage halved the concentration of butyric acid when compared with untreated herbage (P<0.0001). Wilting doubled the silage DM concentration. The microbial activity was restricted due to osmosis and less butyric acid, other organic acids and ammonia were produced in the wilted silage. The fermentation pattern of the legume-grass mixture silage was somewhat superior to that of the grasses. The mixed silage had a higher nutritive value and slightly lower butyric acid, acetic acid and ammonia concentrations at a significance level of P<0.05. The conclusion is that addition of Superben to various silage crops, or crop wilting improves silage fermentation.

Key words: butyric acid, dry matter, fermentation, hexamine, lactic acid, organic acid.

V. Veinla, M. Asi, P. Kaar.  
  Technological design of the manure disposal system 179
Technological design of the manure disposal system. The stationary manure disposal system designed in the Institute of Agricultural Engineering EAU is today intro-duced in the cattle farms with different size and layout. The system consists of a “walking” reversible bar-scraper units for cleaning the litter alleys, a reversible bar-scraper cross conveyer and a manure press unit (Fig. 1). If the manure storage is far from the cowshed, a piston pump is recommended to transfer the manure. The cross conveyer and the press unit are usually located in the centre or near the end of the cowshed (Fig. 1).

The aim of the present study is to describe how the suitable equipment duties could be calculated. To determine the “walking” scraper conveying capacity the manure disposition across and alongside of the cowsheds litter alleys was measured (Fig. 2, 3, 4). The scraper unit’s working time required for the litter alley cleaning is found by formulae (13, 14). The direction of the scraper body and scraping blades is changed at both ends of the litter alley. For that purpose the operating mechanism (Fig. 7) was designed. The mechanism’s operating principle is described and the ratios between geometrical parameters of its parts are analysed.

The reversible scraper unit, the cross-conveyer and the press-unit (piston pump) have quite different duties and capacities. Usually the walking scraper’s blades drag a pile of manure with the mass 300…400 kg into the cross-conveyer’s channel during a short time for a relatively long interim. The cross conveyer portions that bulk out by 15…20 kg to feed the manure press unit or piston pump. To minimise the equipment’s idle work the flow agreement is required. By formulae (20, 21) the volumes for an intermediate control container are calculated. Simultaneous work of the scraper unit, the cross-conveyer and the press-unit is obviously unsuitable. By (20) the suitable time for the cross-conveyer and the press-unit simultaneous work is determined, considering the intermediate container emptied before the supply by scraper unit manure portion. The equipment time schedule could be designed by formulae (13, 20, 23).

  Activities of the Academical Agricultural Society 193
  New members of the Academical Agricultural Society 195

Cloud of Keywords
118’ 1997_2_kroonika acid additive agricultural based benzoate breeding butyric class conveyer crop cross cuts degree designed determined disposal effect experimental fermentation fertility flowers formulae free grass grasses herbage hexamine high higher hybrid infection initial intermediate investigated isolate isolates i’ kvx17 kvxolev kvxsulev legume less level litter manure material matter mixture partially piston plants pollination pollinative polymorphism population populations potato pump quality resistance reversible scraper self silage sodium stands sterile superben susceptibility three unit untreated variant varieties variety virus wilting work ‘ellerslie ‘jõgeva ‘sante’ ‘sarme’ ‘timate’




Estonian Academic Agricultural Society

Editor in Chief

Alo Tänavots


Fr. R. Kreutzwaldi 1,
51014 Tartu,






Agraarteadus : Journal of Agricultural Science 1990

Online since 
1997 * VIII * 4



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