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Changes in grain moisture, germination and vigour of three wheat cultivars packed in paper bags and stored for one year under four different conditions of environmental temperature and relative humidity (RH) were investigated. During the first ninety days of storage significant reduction in grain moisture content of 4, 2.5 and 0.9 %, respectively, under 40 °C, 25 °C and 4 °C and RH of 45 % occurred. Subsequently grain moisture remained constant until the end of storage. Seeds of examined cultivars lost their germination ability and vigour only under elevated storage temperatures. Germination and vigour loss after one year of storage differed between cultivars being higher for seeds kept under 40°C, RH = 45% (35-85 % and 55-94 %, respectively), than under 25°C, RH = 45 % (10-20 % and 15-22 %, respectively). Obtained data indicate significant influence of storage conditions on moisture content, germination and vigour changes during storage of wheat seeds, as well as varietal dependence of seed viability.

The present seed production of maize in the Republic of Croatia is reduced in relation to the period before the Patriotic War. Production of maize seed in Croatia was between 14,000 and 21,000 tons yearly in the period from 1981 to 1986. It was reduced to 8000 tons yearly in the period from 1989 to 2001. Today, Croatia has 13 processing centres with the capacity approximately 50,000 tons of seed, but utilisation of these capacities is about 40%. Decreasing of maize seed production is caused by market reduction (less areas under the maize in Croatia) and reduced export of maize hybrids seed. Before the Patriotic War, Croatia participated in the total seeds export of former Yugoslavia with 35-40%. The largest export of maize seed was 1983, with the approximately 10,700 tons. Seed export of Bc, Os and KWS hybrids was the Eastern European market, while the seed of Pioneer, SES and part of KWS hybrids was exported on the Western European market. Nowadays, production of maize hybrids at Croatia is about 5000 ha (in the world on about 1 mil. ha) with the seed export of 3500 tons, approximately. Today, the largest amount of maize seed is exported in Spain, Germany, Italy, Portugal, Bosnia and Herzegovina, Macedonia, Slovenia and Turkey. The total value of maize seed production is 20 mil. Euro, approximately. Seed export should be the basic strategic aim in the program of seed production development because areas occupied with mercantile maize (approximately 400,000 ha) cannot completely employ capacities for the production of seed.

Wheat seed is a very good medium for development of numerous saprophytes and parasitic fungi species that influence biological characteristics of seed and its value. The presence of fungi, especially parasitic species, causes some changes (colour changes, empty seed, spots, mould, deformation) in seed macroscopically visible. The most common agents are facultative parasites (Fusarium graminearum, Helminthosporium sativum, Septoria nodorum). They are believed to be extremely harmful since their influence on the essential seed functions are negative. The research was done on two wheat cultivars (Ţitarka and Demetra). Significant differences in micopopulation were registered at two points - immediately after harvesting and after seed storage - despite the used methods (filter paper, moist chamber, deep-freezing, germination in sand) and applied fungicides (Raxil 2WS and Vitavax 200 FF). The most numerous micopopulation was established in non-treated seed after harvesting by freezing method. There were 9 fungi genera determined of which weretwo facultative parasites. All research done on treated seed showed that there was a smaller number of fungi species and the percentage of the infected seed was lower. Under the influence of Fusarium graminearum as well as other fungi species the ability of germination was decreased. According to all used methodes both wheat cultivars seed treated with fungicides were chacarterized by a lower level of infection and better germination during both research periods. By the analyses done on the stored seed a higher percentage of nongerminate seed and deformed germs were established, especially on the treated wheat seed.