The effects of ultrasonic treatments on the germination and seedling growth of aged tall fescue (Festuca arundinacea) and Russian wild rye (Psathyrostaehys juncea Nevski) seeds were determined using orthogonal matrix experimental design with four ultrasonic factors. The multivariate analysis of variance detected significant differences and coupling effects of the pair-wise factors. The activities of Superoxide Dismutase (SOD) and Peroxidase (POD) and the Malondialdehyde (MDA) content were affected. The ultrasonic treatments had positive effects on the germination percentage (GP) of the aged seeds and the growth of the seedlings (GS) and therefore we provided a basic evidence for the application of ultrasonic treatment to pretreat aged grass seeds. For the four ultrasonic factors, the optimal conditions were a sonication time of 36.7 min, a sonication temperature of 35 °C, an output power of 367 W and a seed soaking time 4.1 h after binary quadratic regressions analyses. The ultrasonic treatment has the potential to improve seedling growth. Moreover, the longevity of the tall fescue and the Russian wild rye seeds was approximately 9.5 and 11.5 years, respectively, under natural conditions of storage. The physiological mechanisms that might contribute to the improved GP and GS were discussed.

Seed marks the beginning of each plant production and therefore ensuring its quality is the priority of modern seed science and a prerequisite for obtaining high yields of all plant species. Determination of seed quality and its viability indicates what seed lots can be placed onto the market, and for that reason it is very important to have reliable methods and tests to be used for seed quality and seed vigour testing. The term vigour of viability is used to describe the physiological characteristics of seeds that control its ability to germinate rapidly in the soil and to tolerate various, mostly negative environmental factors. MCDONALD grouped vigour tests into three groups: Physical tests - determine seed characteristics such as size and mass. These tests are inexpensive, quick, can be applied to large number of samples, and are positively correlated with seed vigour. The main feature of seed development is accumulation of nutritive materials, which is also in direct correlation with vigour, i.e. with size and mass of seed; Physiological tests - using germination and growth parameters. There are two types of these tests. First type, when germination is done under favourable conditions (standard laboratory germination, and test of growth intensity). Second type, when seed is exposed to unfavourable environmental conditions (cold test, accelerated aging test, and Hiltner test); Biochemical tests - are considered as indirect methods for estimation of seed value. These are Tetrazolijum test, conductometric measurements, enzyme activity and respiration

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In order to determine an optimum ratio of vetch and wheat (Triticum aestivum L.) components in their mixture, there has been carried out a four-year trial (autumn 2005-spring 2009) aimed at the yield and quality of winter vetch haylage. The sowing rate of winter vetch was 120 kg ha-1 , while the sowing rate of winter wheat was 0, 15, 20, 25 and 30 kg ha-1. An increased proportion of the cereal in its mixture with vetch significantly decreases the stand lodging, have a positive influence on forage yield, but haylage quality is of a poorer quality. Quality characteristics such as crude protein and lignin content, total digestible nutrients, dry matter intake and relative feed value were highest in monoculture common vetch followed by mixture with the lowest rate of wheat. Neutral detergent fiber content was positively affected by intercropping. There were no significant differences among treatments for acid detergent fiber content, digestible dry matter, and net energy for lactation. The most favorable balance between the haylage yield and quality, as well as the highest CP yield (1482 kg ha-1), was achieved by the mixture of 120 kg ha-1 of the vetch seed and 15 kg ha-1 of wheat.

The objective of this study was to develop diallel population hybrids by crossing selected germplasm and to determine the gene effects and genetic control of yield and yield components using diallel analysis. A complete diallel including reciprocals was made during 2003 and 2004 between five alfalfa cultivars of different geographic origin. For each pairwise cross, five plants were chosen at random from each of the two cultivars (*100 florets per plant) to obtain the F 1 generation. A spaced plant field was established in 2006 which included the five alfalfa cultivars (parents) and their 20 diallel hybrids (F 1 ). The results of the diallel analysis suggest that the genetic control of major agronomic traits is determined by both additive gene action (accumulation of frequency of desirable alleles represented by significant GCA effects) and nonadditive gene action (complementary gene interactions represented by significant SCA effects). This type of gene action expression in alfalfa also determines the way in which breeding is carried out and brings about changes in the methods used and has given rise to the idea of the semi-hybrid breeding of this crop. The concept involves: breeding alfalfas within the population, identification of heterotic germplasm, and the production of seed of the population hybrid (PH).