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The aim of the paper was to examine the allelopathic influence of aqueous extracts of herbs and medicinal plants on the quality parameters of aged soybean seeds. The research was carried out at the Institute of Field and Vegetable Crops in Novi Sad on aged seeds of two soybean varieties, NS simba and NS viseris. The seeds were aged for 20 months. In order to determine the allelopathic effect, the seeds were primed in aqueous plant extracts: geranium (Geranium sinense), dill (Anethum graveolens), andy everlasting (Helichrysum arenarium), creeping thyme (Thymus serpyllum), celery (Apium graveolens), oregano (Origanum vulgare), basil (Ocimum basilicum), lemon balm (Melissa officinalis), rosemary (Rosmarinus officinalis), wormwood (Artemisia absinthium), peppermint (Mentha x piperita), sage (Salvia officinalis), and lavender (Lavandula angustifolia). The results show that it is not possible to talk about the universal application of a particular aqueous extract, because the effect of the allochemicals was significantly influenced by the variety. In the variety NS viseris, all aqueous extracts except Melissa officinalis, significantly reduced GE, GP, and VI. The most negative effect was achieved with the use of Apium graveolens, Thymus serpyllum, and Ocimum basilicum. Apium graveolens and Thymus serpyllum also had the greatest impact on quality reduction in the NS simba variety. However, in the NS simba variety, a significant increase in seed quality was achieved in addition to the reduction. The use of the aqueous extract of Salvia officinalis increased GE and GP by 13.7%, and VI by 10.21%. A positive effect was achieved with the use of Melissa officinalis. All aqueous extracts had a significant effect on T50 in both varieties, even the aqueous extracts that had a negative effect on GE and GP.

Red clover (Trifolium pratense L.) is the second most important perennial forage legume in the Republic of Serbia, cultivated on 90-120.000 ha. The objective of this study was to determine the effects of cutting management on seed yield, some seed yield components, and seed quality of the NS red clover variety Una during the second and third year of growing. Five cutting managements with variable dates of initial cutting were tested in the 2019-2020 period. The first cutting was used for seed production in the C1 management and the second growth in the C2-C5 managements (C2-budding, C3-start of flowering, C4-mid of flowering, and C5-full flowering). In all cutting systems, significantly higher seed yields were achieved in the second year of growing. Unfavourable environmental conditions for pollinators as well as thinning of red clover crops in the third year of growing are the main reasons for low seed yields. The highest seed yield (539 kg/ha) was achieved in the C2 cutting management in the second year of growing. The cutting management had no significant effects on red clover seed quality.

The objective of this study was to examine the effects of different priming treatments on seed quality and initial growth and development of garden pea. For this purpose, three garden pea cultivars, developed at the Institute of Field and Vegetable crops, Novi Sad were examined. The laboratory experiment was conducted under optimal conditions. Seeds were primed in water (hydropriming), 0.5% KNO3 solution, and -0.49 MPa PEG solution for 24 hours; non-primed seeds were controls. The results showed that the percentage of germination, shoot and root length, and mean germination rate significantly increased after the tested priming treatments, while the percentage of abnormal seedlings and mean germi­nation time were significantly decreased after the priming treatments compared to the control. The increase of fresh and dry seedling biomass was significant only in cv.1 and cv.2. Despite the genetic diversity of pea cultivars, the results indicated that the examined seed priming treatments enhanced seed quality and vigour of garden pea cultivars.

The aim of this study was to examine the impact of seed priming on seed quality parameters (germination energy, germination, seedling length and vigor index) of sorghum (Sorghum bicolor L. Moench) and sudangrass (Sorghum sudanense Pers.). The experiment was performed at the Institute of Field and Vegetable Crops, Novi Sad, Serbia. The research was conducted on the seeds of the sorghum variety NS Džin and sudangrass variety Srem. Distilled water and aqueous extracts of young willow branches (Salix matsudana) and mature banana fruits (Musa x paradisiaca) were used to prime the seeds. The seeds were primed for: 1 h, 3 h, 6 h, 12 h and 24 h. The results showed that priming sorghum and sudangrass seeds in aqueous extracts of young willow branches and mature banana fruits can have a positive effect on seed quality parameters: germination energy, germination, seedling length and vigor index. The greatest effect on germination energy and seed germination was achieved in sudangrass by using an aqueous extract of young willow branches. The increase was 9.30% and 9.20%, respectively. Priming sorghum seeds in aquatic extracts of mature banana fruits had the greatest effect on seedling length and vigor index. The increase was 36.86% and 40.33%, respectively. For all research parameters, priming for 3 h was the most effective. However, in addition to the positive effect, priming can also have a negative effect. The most significant reduction was found on sorghum seeds, when primed in an aqueous extract of mature banana fruit for 24 hours. Germination energy and germination were reduced by 7.14% and 9.30%, respectively.

Red clover (Trifolium pratense L.) is a meadow and pasture species in natural habitats and also a cultivated species used for animal nutrition. The aim of this research was the assessment of the diversity of 46 red clover accessions based on morpho-productive traits. The traits were investigated according to the UPOV descriptors for red clover-number of internodes, number of branches, stem length, stem thickness, middle leaflet length, middle leaflet width, green matter yield and dry matter yield. The principal components analysis (PCA) explained 74% of the variance of the standardized data and showed relationships between 46 red clover accessions and eight morpho-productive traits, associations among traits and performance of accessions. Among the determined Euclidean distances, the smallest value was obtained for the accessions Rotra and Titus (0.048), the largest value was 1.099 for a pair of NCPGRU2 and Čortanovci accessions, and the average value was 0.380. Two clusters of 46 red clover accessions were separated in the dendrogram based upon UPGMA (Unweighted Pair-Group Method with Arithmetic mean) for eight morpho-productive traits. The first cluster included two subclusters, while the second cluster contained four subclusters. The grouping of the accessions from the red clover collection by the UPGMA cluster analysis can be linked to the geographical origin of the accessions: central and Southern Europe for three subclusters and northeastern Europe for one subcluster.

Red clover is an important perennial forage legume and a rich source of highly nutritional voluminous forage for livestock feed, which is continuously improved by plant breeding efforts that rely significantly on trait correlation studies. A two-year field trial was conducted at Rimski Šančevi, Novi Sad, Serbia. The aim of this research was to assess correlations of important morpho-agronomic traits and forage quality properties of 46 red clover accessions of diverse origins. The highest Spearman's correlation coefficient (0.97, p

The aim of this study was to examine the influence of electrostatic fields on seed vigor (VI), mean rate of germination (MGR) and coefficient of velocity of germination (CVG) of five soybean genotypes. Testing was conducted at the Novi Sad Institute of Field and Vegetable Crops on the seeds of five soybean varieties: Sava, NS 2024, NS 1347, NS 3127, and NS Blackstar. The seeds were exposed to different voltages of direct current (DC): 0 V (control), 3 V, 6 V and 9 V, to which the seeds were exposed for 0 min (control), 1 min and 3 min. The application of DC can be a suitable method for improving VI, MGR and CVG. In addition, the results indicate that it is necessary to adjust the DC treatment (voltage and duration of exposure of seeds) to a particular genotype, since inadequate treatments may deteriorate the quality of seeds.

Seed vitality and vigour are the two most common parameters related to seed quality. It is crucial to have reliable methods and tests for seed quality and seed vigour testing. The standard germination test can be used to predict field emergence, but laboratory seed testing conditions are often in conflict with field conditions. Validated tests for vigour evaluation in legumes are the conductivity test, the accelerated ageing test and the tetrazolium test. Also, other types of vigour tests have been used to solve different problems in the seed sector. The modern approach, the computerised image analysis of legume seeds and sprouts, based on interactive and traditional methods, is a promising alternative for vigour determination.

This paper presents the plant genetic resources maintained by the Center of Excellence for Legumes of the Institute of Field and Vegetable Crops, National Institute of the Republic of Serbia. The genetic resources of legumes (soybean, alfalfa, red clover, pea and vetch) are an invaluable source material and a rich source of genetic divergence for the development of varieties adapted to specific agricultural and environmental conditions. Soybean is the most important of all cultivated legumes and occupies the largest area under cultivation. The alfalfa collection consists of over 800 genotypes with different agronomic traits and dormancy values. The novel alfalfa breeding concept - breeding for yield per se, based on natural heterosis in the development of half hybrids - was introduced in the late 20th and early 21st centuries. The Center of Excellence for Legumes has 757 soybean genotypes, 655 red clover genotypes, about 730 pea genotypes and 495 vetch genotypes. The development of the winter pea variety for grain (NS Mraz), the first of its kind in South-Eastern Europe, was significant for science.

The aim of this paper was to examine the influence of the electrostatic field on seeds of soybean (Glycine max L), vetch (Vicia spp. L.), pea (Pisum sativum L.), grass pea (Lathyrus sativus L.) and chickpea (Cicer arietinum L.) which were selected at the Institute of Field and Vegetable Crops in Novi Sad. The DC voltage of 9V was used. The durations of seed treatment were 0 (control), 1, 2 and 3 minutes. The trial was set up as a randomized block design with four replications. 4x100 seeds of each variant and control (untreated seed) were treated. After treatment, seed quality was examined using a germination test (optimal temperature) and a cold test (low temperature). The results of the study showed that the effect of the electrostatic field on seed quality depended on the plant species, the time of seed treatment and the temperature conditions in which the seed germinated after treatment. The increase in germination energy ranged up to 18.18% in vetch, and a decrease of up to 12% was observed in chickpea. The application of the electrostatic field had a significantly greater impact on seeds that were exposed to low temperatures in the germination process after treatment. The increase in seed germination ranged up to 82.35% in chickpeas, and the decrease amounted to 92.68% in peas. In addition, the obtained results indicate that it is not possible to talk about the universal application of a certain duration of seed treatment.

Field peas are mostly used for animal nutrition in the Balkan region and in the countries of the former USSR, while in the countries of Western Europe, Canada, the USA and the Middle East they are mostly used for human nutrition. Over three years (2010-2012), the yield and grain yield components of the most widespread field pea varieties were examined. The lowest number of plants was determined in 'NS Junior' intended for combined use (65 plants/m2), while 'Dukat' and 'Partner' had 88 and 85 plants/m2 on average, respectively. The average stem height was 158 cm for 'NS Junior', and 65 and 70 cm for 'Dukat' and 'Partner', respectively. 'Dukat' (4846 kg/ha) and 'Partner' (4521 kg/ha) had significantly higher grain yields compared with 'NS Junior' (2717 kg/ha). The content of crude protein in the grain was highest in 'NS Junior' (27.6%), while 'Dukat' and 'Partner' had lower contents (23-25%).

The first local cultivar of winter pea for grain, 'NS MRAZ', was developed by pedigree selection from the hybrid population created by crossing local populations and one French line of pea. The cultivar has a high seed yield potential, exceptional earliness and tolerance to low temperatures. Its average plant height is 75-85 cm; it is of the afila type of pea, tolerant to lodging and of uniform maturity. Its genetic potential for seed yield is more than 7,000 kg ha-1, and it achieved an average seed yield of 5,110 kg ha-1 in three-year trials, while seed yield in production conditions was above 5,500 kg ha-1. Thousand-grain weight is about 200 g, which was the goal achieved in reducing the amount of seed per unit area. Protein yield ranged from 1,100 to 1,200 kg ha-1.

Alfalfa (Medicago sativa L.) is the most important forage crop in the world, regarding growing area and economic value, because of its high yield level, good persistence, high protein content and energy value. In alfalfa, concept of intra-population breeding means direct selection for yield, through recurrent phenotypic selection using some form of progeny testing. Significant differences between genotypes were found for green forage and dry matter yields. The observed variation for both yield traits was much higher at population level than for the selected plants that will form new improved population. In the next steps of breeding process selected plants will be intercrossed in isolation to develop a new, improved population. Alfalfa breeding programs should focus on yield per se, with the use of old and new knowledge on the genetic control of yield and with adaptation of existing or developing new breeding procedure.

Alfalfa is the most important forage crop in Serbia grown for high yields of quality fodder. In order to expand alfalfa production on pseudogleys, research was conducted in the vicinity of Kraljevo. Results suggest the potential for growing alfalfa on acid soils in Serbia. The combined use of 2.5 t ha-1 and 5 t ha-1 lime and 30 t ha-1 manure on the pseudogley increases the soil pH, humus content and available phosphorus and potassium levels, while decreasing the content of mobile aluminum, thus making the soil suitable for alfalfa production and high biomass yields (115.9 t ha-1) during 3-4 years of stand utilization.

It is essential to apply advanced management for successful production of alfalfa hay with premium quality (high content of protein and minerals). The maximum yield and the best quality of alfalfa in Serbia can be obtained by cutting four or five times per year. In alfalfa stands, use of cutting system with three cuts per year is inefficient and does not allow full exploitation of cultivar genetic potential and environmental conditions. It is possible, and economically beneficial to grow alfalfa on pseudoglay soils after application of lime and organic manure, with recommended rates 2.5 t ha-1 lime and 30 t ha-1 manure. Cutting alfalfa at the beginning of flowering stage (5 cuts per year) provides hay with better quality - higher content of crude protein and lower portion of fibre fractions (neutral detergent fibre, acid detergent fibre, acid detergent lignin), and there is no reduction in dry matter yield. There is no differences in alfalfa quality after application of lower (2.5 t ha-1) and higher dose (5.0 t ha-1) of lime + 30 t ha-1 of organic manure, but there is significant increase of dry matter yield and protein yield per hectare followed by higher level of metabolic energy per unit area. Upon the results of this study, base of successful alfalfa production would be to develop management system and cultivars for different environments that would maximize hay yields without significant loses of quality.

Recently, heavy metals concentrations increased in some agricultural areas due to the consequences of anthropogenic impacts. The aim of this study was to determine the level of heavy metals (As, Cr, Ni and Pb) in Medicago sativa L. and Trifolium pratense L. grown on fluvisol, in order to obtain information on safety of these nutrients. The total content of Pb, As, Cr and Ni in the samples of fluvisol was above the maximum allowable amount. The content of heavy metals in Medicago sativa L. and Trifolium pratense L. was below the critical and toxic concentrations in all samples originating from contaminated soil. It was concluded that the accumulation of heavy metals in plants did not depend only on the total content in soil, but also the affinity of the plant, and individual and interactive effects of various soil properties. No statistically significant differences in the accumulation of heavy metals between Medicago sativa L. and Trifolium pratense L were observed. It is necessary to further control of heavy metals in the investigated area, in order to prevent their entry into the food chain and provide healthy food.

Alfalfa (Medicago sativa L.) is an important forage legume in Libya. The genetic diversity of nine alfalfa domesticated varietal populations was studied using thirteen RAPD primer combinations. The number of polymorphic fragments detected per primer combination ranged from 8 to 46 bands with an average of 24 bands. The number of polymorphic bands detected was from 6 (Atalia population) to 37 (Gabsia population). The lowest genetic distance was 0.058 and the highest was 0.655. The average genetic distance was (0.356). The dendrogram based on Ward’s minimum variance clustering method grouped the nine populations into the two main clusters. The first group included Fazania, Atalia, Masratia, Zawia, Denamo Ferade and Arezona. The second group was composed of Tagoria, Gabsia and Wade Alrabeh. The simplicity of RAPD assays for detection of genetic polymorphisms is confirmed in our study, and results can be utilized in breeding practice.

Alfalfa is one of the most important forage crops in the world and it is spread across the globe on over 30 million hectares. The objectives of this study were to assess the importance and effectiveness of progeny tests used in alfalfa breeding for dry matter yield and crude protein content and to determine which of these tests provides the best information for choosing parental components to improve the success of alfalfa breeding. The experiment tested 35 alfalfa genotypes of different geographic and genetic origin. The rank correlations obtained in our study indicate that open pollination and self pollination progeny tests are effective tools for evaluating alfalfa parents for dry matter yield and crude protein content, respectively. Alfalfa breeding for improved quality can be effective if crosses are made between genetically divergent populations in order to produce hybrid combinations that will be used as donors of genes for quality in the development of new synthetic cultivars, all the while making sure that yield is maintained as an essential factor in alfalfa breeding.

A small-plot trial with eight Australian barrel medic (Medicago truncatula Gaertn) cultivars was carried out in 2010 at Rimski Šančevi. The average green forage and forage dry matter yields were highest in Jemalong (30.7 t ha-1 and 7.3 t ha-1) and Parabinga (30.7 t ha-1 and 8.0 t ha-1). Forage dry matter crude protein content ranged between 150.8 g kg-1 in Parabinga and 179.4 g kg-1 in Jester. Forage neutral detergent fibre content varied from 305.2 g kg-1 in Sephi to 458.8 g kg-1 in Caliph, while the average forage acid detergent fibre content was 312.8 g kg-1. The average seed yield for all cultivars was 281 kg ha-1 and may be considered satisfying, as it was obtained in a very rainy and warm growing season. Jemalong and Parabinga had the highest aboveground nitrogen yield (190 kg ha-1 and 193 kg ha-1) and thus the greatest potential for green manure.

Alfalfa breeding programs in the world started at the beginning of the last century, while in Serbia they started in the middle of last century. The contradictory results on the genetic gain in alfalfa breeding for yield in the world and in our country had as a consequence the yield analysis from different experiments, in different locations, through different years neglecting the interaction germplasm x year (age of alfalfa fields), and germplasm by environment (ecological conditions related to site or conditions in the year). In order to assess the progress in breeding alfalfa for yield in our country, new experimental populations were compared with old and new alfalfa cultivars developed in the Institute of Field and Vegetable Crops Novi Sad, Serbia. Yield differences between cultivars and experimental populations of alfalfa were not significant. New alfalfa breeding programs should focus on yield per se, with the use of new knowledge on the genetic control of yield and with adaptation of existing or creating new breeding procedure.

A two-year study (2006 and 2007) was carried out to examine the effect of row spacing and seeding rate on seed and dry matter yield of red clover in a production system for mixed utilization. Field experiments were conducted at the field of Agricultural Highschool in Futog, Serbia. Red clover crop was established in three row distances: 12.5 cm, 25 cm and 50 cm, and three seeding rates: 2.5 kg ha-1, 5 kg ha-1 and 10 kg ha-1. Studies have shown that in the location of Futog (region of south Bačka), sowing 10 kg ha-1 with row distance of 25 cm provides red clover seed yield of 482.4 kg ha-1 in the first year of growing and 546.2 kg ha-1 in the second year. The highest yield of dry matter grown in the system of production for mixed use (seed-forage) in Futog was achieved with the row distance of 12.5 cm and seeds rate of 10 kg ha-1.

When breeding alfalfa for yield performance, it is necessary to use high-yielding parents obtained by different breeding methods. The assumption at the onset of this research was that crossing highest-yielding domestic cultivars with divergent populations from geographically distant breeding centers could result in the expression of heterotic effects in their hybrids contributing to increased alfalfa yield. The objective of this study was to determine yield and yield components and heterotic effects in hybrid progenies obtained by crossing the domestic cultivars NS Banat ZMS II and NS Mediana ZMS V with the cultivars Pella, Dolichi and Hyliki from Greece, UMSS 2001 from Bolivia and Jogeva 118 from Estonia in two series. The field trial planted in 2006, included 13 F1 hybrids and 6 of 7 initial parents in both series. Heterotic effects for yields of forage and hay were observed in 4 combinations (C NS Banat ZMS II x E Hyliki; C NS Banat ZMS II x E UMSS 2001; C NS Mediana ZMS V x E Hyliki; C NS Mediana ZMS V x E Dolichi). The populations that exhibited heterosis in a set of crossings are recommended for use as parent components for development of high-yielding synthetic alfalfa cultivars. .

Red clover (Trifolium pratense L.) is botanically a perennial, although it often behaves as a biennial. The crop usually lives 2 to 3 seasons in most clover-growing regions of the world and is generally conceded to be lacking in persistence. The objective of this investigation was to analyze the production potential and persistence of domestic and imported red clover varieties. Experiments were conducted at Rimski Šančevi Experiment Field during the period 2004-2006. The experimental materials were six varieties (K-17, Kolubara, Una, Viola, Start, Nike) which were analyzed for the most important production characteristics: yield of green mass, dry matter yield and persistence. .

The effects of row spacing (12,5 cm and 50 cm) on seed yield components and seed yield of winter-sown hairy, Hungarian and common vetches (V. villosa Roth, V. pannonica Crantz and V. sativa L.) were investigated in this paper. Number of plants per m2, number of stems per plant and per m2, crop height, plant length, lodging index, number of pods per plant, number of seeds per pod, 1,000 seed weight and seed yield were determined. Increased row spacing resulted in increased crop height by 13.6 %, decreased plant length by 8.5 %, increased lodging index by 22.3 %, increased number of stems per plant by 57.0 %, number of pods per plant by 43.5 %, number of seeds per pod by 14.7 %, 1,000 seed weight by 4.7 % and seed yield by 29.0 %. The highest and the lowest seed yields were obtained in Hungarian and hairy vetch, 1,380 kg ha-1 and 784 kg ha-1 respectively. .

The effect of seed moisture content at harvest on the most important parameters of dry pea was examined. The seed moisture content, germination energy, germination, proportion of abnormal seedlings and 1000-seed weight were analyzed in three dry pea cultivars (Jezero, Javor and NS-Junior) and at eight harvest stages. At the first harvest stage, seed moisture content was 20.44%, while at the eighth stage it was 11.26%. The best seed quality, with germination energy of 81.70% and germination of 90.11%, was at the sixth harvest time when seed moisture content was 12.92%. The poorest seed quality one was at the first harvest stage, with germination energy of 68.55% and germination of 78.56%. Cultivar Jezero, with shorter growing season, determinant stem growth and uniform maturity, had the highest germination energy (82.00%), germination (92.21%) and percent of abnormal seedlings (1.96%). Cultivar NS Junior, with the longest growing season, indeterminant stem growth and non-uniform maturity, had the lowest germination energy (70.39%) and germination (76.54%), and the highest percent of abnormal seedlings (3.58%).

Breeding of perennial legumes for many agronomic important traits like grain yield, persistence, longevity, resistance to diseases and pests, resistance to limiting abiotic conditions and polyploidy is more efficient and precise if genetic markers are used. Estimates based on isozyme polymorphism may underestimate overall levels of genetic variation because they are sampling only coding regions of DNA that may be conserved to maintain the function of the enzymes. The complete coverage of a genome can be achieved only by the use of molecular variability indicators (DNA polymorphism), i.e. molecular markers. Molecular markers are independent of environmental influences and can be detected in all plant development stages. The main aspects of genetic markers use in perennial legumes breeding are: germplasm characterisation, genetic linkage mapping, QTL analysis, marker assisted selection (MAS), variety identification and protection of plant breeders' rights.

In plants with bisexual flowers, the development of hybrids and F1 seed production is only possible by using cytoplasmatic male sterility. The discovery of such sterility and the maintainers has made it possible to utilize the phenomenon of heterosis to improve yields and yield components in forage sorghum. It has been shown that the best way to develop forage sorghum hybrids is to cross grain sorghum as the female parent and Sudan grass as the male. The objective of this study was to develop a forage sorghum hybrid for the production of green matter to be used either fresh or for silage. The sorghum hybrid developed in these efforts (Siloking) is intended for multiple cutting, as the basal nodes produce buds and regrowth takes place. The performance of the new hybrid with respect to yield and quality was compared to that of the forage sorghum cultivar NS Džin. In a two-year study conducted under different growing conditions in four locations, Siloking produced an average green matter yield of 86.29 t ha-1 (two cuts), a dry matter yield of 25.34 t ha-1, and a crude protein content of 11.85 %. Siloking outperformed NS Džin in terms of yield and quality. .

In 2007 and 2008, the trials of the Department of Variety Protection and Registration of the Ministry of Agriculture, Forestry and Water Management of the Republic of Serbia were carried out on four locations, including two new Novi Sad spring feed faba bean lines, B-412 and B-413, and the control cultivar Uran. In average, the highest grain yield was in the cultivar Gema (2905 kg ha-1), although there were no significant differences between three tested cultivars. In comparison to the control, Gema and Šarac had significantly higher crude protein content in grain dry matter, with 341.4 g kg-1 and 341.1 g kg-1. .

The main task of breeding red clover, the second most important perennial forage legume, is to develop cultivars giving high forage yields of excellent quality. Goals set before red clover cultivar development are achieved by different breeding methods. Previous research has shown that the most important methods used in red clover breeding are mass selection, individual selection, recurrent phenotypic selection, the polycross method, hybridization, and polyploidy. Mass selection is one of the oldest methods and has proven highly effective in improving highly heritable traits. Individual selection and hybridization have been shown to be highly effective in increasing protein content. Recurrent phenotypic selection is very effective when breeding for resistance to some diseases and pests as well as when developing genotypes tolerant of the 2,4-D preparation. The main idea behind the polycross method is selection of clones with a good GCA to be used for developing improved synthetic cultivars. Since no tetraploid forms of red clover have been discovered in nature, induced polyploidy receives special attention in the breeding effort, mainly for the purpose of increasing forage yields. .

Natural alfalfa seed from contracted 1997-2000 production in the Vojvodina province was processed at the Forage Crops Department of the Institute of Field and Vegetable Crops in Novi Sad. The seed was processed on a Kamas Westrup, while the dodder was removed using a trifoline magnet. Twelve samples were taken from the seed producers in each of the four study years. Each sample was divided into three parts (one for the producer, one for laboratory analysis and one for the processor(. The greatest purity was achieved in 2000 (53% on average), followed by 1998 (48%). The year 1997 had a considerably lower purity (42,8%), while 1999 had the lowest (only 34,8%). The smallest amount of processed seed was obtained in 1999 (28,8 t). In the year 2000, which was fairly favorable seed production-wise and had the largest utilization percentage *53,7% of pure seed), a total of 77,5 t was processed. In 1997, five alfalfa cultivars were used seed production, while in 1998, 1999 and 2000 there were three each. .

Experiments were conducted at the Rimski Sancevi Experiment Field in the period 1998-1999 The experiment object were six varieties and two populations of red clover. In both years, we determined photosynthetic indi­cators (LAI - leaf area index, LAd - leaf area density, NAR - net photosynthetic productivity) per individual cuttings and the total yield of vegetative mass. The obtained data were statistically processed by the path coefficient analysis. High simple correlations between the photosynthetic indicators (LAI and LAd) and the yield of green forage were found in all cuttings in both years. Highly significant (**) direct effects of NAR and LAI on the yield of vegetative mass were found in almost all cuttings. LAI and LAd exhibited the highest total effects on the yield of vegetative mass. The coefficients of multiple determination between the analyzed photosynthetic indicators and the yield of vegetative mass were high (96.88 - 99 49 %) in all cuttings. .

Ten alfalfa varieties were tested at the Rimski Sancevi Experiment Field in the period 1991-1994. The following characteristics were analyzed: yield of dry matter, yield of green forage, stem length and diameter, lamina length and width, regeneration rate, number of intemodes, proportion of leaves and the content of crude proteins. Stem length, yield of green forage, regeneration rate and the proportion of leaves exhibited direct positive effects on dry matter yield. Number of internodes, lamina length and the content of crude proteins exhibited negative direct effects. Yield of green forage, stein length and regeneration rate exhibited also indirect positive effects, via other characteristics. They may be used as selection criteria in alfalfa breeding for increased yield of dry matter. In addition to the significant positive direct effect, the portion of leaves had negative indirect effects, via green forage yield, stem length, growth rate and the content of crude proteins. It is therefore not applicable in alfalfa breeding for increased yield of dry matter. .