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Smooth bromegrass (Bromus inermis Leyss.) is rhizomatous perennial forage grass species spread all over Serbia, mostly beside the roads and at the edges of semi-xerophylous or xerophylous natural grasslands. Stabile and high forage yield, classify Smooth bromegrass in a group of forage grasses suitable for mixtures composing for drought conditions and poor soils in agro-ecological conditions of Serbia. It can be used traditionally for hay production, but also in quality mixtures with legumes for silage or haylage production. Cultivar K-46 is created by multiple phenotypic recurrent selection of populations collected across central Serbia. The main breeding goal was developing of genotypes of Bromus inermis with improved yield and chemical composition of dry matter. Since this grass species generally have been characterised with a lot of large but indelicate leaves, improvement of its biomass quality requires breeding of leaf parameters (size, number, position, etc.). In plot trial on three locations in two years period (2015 and 2016) cultivar K-46 reached average DMY of 6400 kg ha-1. The average height of plants at the moment of cutting was 81.6 cm. Crude protein content was 11.61 g kg-1 of dry matter in the first cut and 13.51 g kg-1 in the second cut, which represents the good quality of grass biomass. New cultivar K-46, which is registered in December 2017, is suitable for mixtures composing for long-lasting and durable grasslands on light, marginal and dry soils. It stabilises land and produces enough amount of quality herbage which can be used with legumes species as complete forage meal for ruminants. It is adapted for cutting and tolerates dry, poor and eroded soils, therefore it shows best results on grasslands on hilly mountainous areas.

The aim of present study was to get comparative data on forage productivity and quality of forage of Checz cultivars of legumes in the conditions of Northern Bulgaria and respectively to select species and genotypes with the potential for successful introduction in the structure of forage production in Bulgaria. Five species of forage crops were observed and the respective cultivars: Egyptian clover (Trifolium alexandrinum L.), cv. Faraon; crimson clover (Trifolium incarnatum L.), cv. Kardinal; annual bird's-foot-trefoil (Lotus ornithopoides L.) cv. Junak; black medick (Medicago lupulina L.) cv. Ekola and white melilot (Melilotus albus L.), cv. Adela. The studied legumes differed significantly in their fodder productivity. They are ranked in the following order of DM yield: white melilot - black medick - annual bird's-foot-trefoil - Egyptian clover - crimson clover. The productivity and participation of Egyptian clover and crimson clover in grasslands varied significantly in years. The biomass of crimson clover had the highest content of crude protein (15.24%) and the lowest of crude fiber (21.69%) and no digestible components. According to the comprehensive evaluation of data on productivity and forage quality of studied annual legumes, black medick could be defined as the species with the highest potential for cultivation in the conditions of the Central Northern Bulgaria. It is characterised by high productivity of green mass and dry matter, it has regrowing ability, it is distinguished by a high content of crude protein (14.92%) and crude fat (4.66%), optimal content of neutral and acid detergent fibers (34.67 and 24.99%) and with high levels of hemicellulose content (9.68%). Energy value of forage of that species, assessed by means of feed unit of milk (FUM) and growth (FUG) was assessed as very high (FUM - 0.69/kg DM and FUG - 0.63/kg DM).

In an individual planting 25 birdsfoot trefoil (Lotus corniculatus L.) accessions constituting the Czech collection were assessed. Fourteen accessions were varieties from the world collection and eleven accessions were wild forms obtained during the collecting expeditions in the Czech Republic and abroad. Morphological, yield and qualitative traits were measured on ten plants of each accession. A total of 34 traits were evaluated. From these values point and interval estimates of means and variation coefficients were produced for each accession as a measure of variability of each particular trait within and among accessions. Point estimates of mean values of accessions formed a data matrix which was then processed by cluster analysis. Accessions with the highest similarity were determined based on these results.

Plant-rhizobia symbiosis can activate key genes involved in regulating nodulation associated with biological nitrogen fixation (BNF). Although the general molecular basis of the BNF process is frequently studied, little is known about its intraspecific variability and the characteristics of its allelic variants. This study's main goals were to describe phenotypic and genotypic variation in the context of nitrogen fixation in red clover ( Trifolium pretense L.) and identify variants in BNF candidate genes associated with BNF efficiency. Acetylene reduction assay validation was the criterion for selecting individual plants with particular BNF rates. Sequences in 86 key candidate genes were obtained by hybridization-based sequence capture target enrichment of plants with alternative phenotypes for nitrogen fixation. Two genes associated with BNF were identified: ethylene response factor required for nodule differentiation ( EFD ) and molybdate transporter 1 ( MOT1 ). In addition, whole-genome population genotyping by double-digest restriction-site-associated sequencing (ddRADseq) was performed, and BNF was evaluated by the natural 15 N abundance method. Polymorphisms associated with BNF and reflecting phenotype variability were identified. The genetic structure of plant accessions was not linked to BNF rate of measured plants. Knowledge of the genetic variation within BNF candidate genes and the characteristics of genetic variants will be beneficial in molecular diagnostics and breeding of red clover.

The aim of the study was to determine phytoestrogen content in fresh-cut legume forage. This issue has been much discussed in recent years in connection with the health and safety of feedstuffs and thus livestock health. The experiments were carried out on two experimental plots at Troubsko and Vatín, Czech Republic during June and July in 2015. Samples were collected of the four forage legume species perennial red clover (variety "Amos"), alfalfa (variety "Holyně"), and annuals Persian clover and Alexandrian clover. Forage was sampled twice at regular three to four day intervals leading up to harvest and a third time on the day of harvest. Fresh and wilted material was analyzed using liquid chromatography-mass spectrometry (LC-MS). Higher levels ( p < 0.05) of isoflavones biochanin A (3.697 mg·g (-1) of dry weight) and formononetin (4.315 mg·g (-1) of dry weight) were found in red clover than in other species. The highest isoflavone content was detected in red clover, reaching 1.001% of dry matter ( p < 0.05), representing a risk for occurrence of reproduction problems and inhibited secretion of animal estrogen. The phytoestrogen content was particularly increased in wilted forage. Significant isoflavone reduction was observed over three to four day intervals leading up to harvest.