Breeding Laboratory Research Articles

Establishing the <i>in vitro</i> culture of and micropropagating edible honeysuckle

Edible honeysuckle is a popular fruit crop. Its therapeutic and health-promoting effects are attributed to a high content of bioactive compounds in the fruits. Unlike the traditional plant multiplication methods, the in vitro propagation allows scientists to obtain high-quality planting material of honeysuckle in a great quantity and within a short time. The research was carried out at the Laboratory of Breeding and Genetic Research on Field Crops of the Federal Scientific Center of Agricultural Biotechnology of the Far East named after A.K. Chaiki. Honeysuckle variety Podarok amurchanam created by the Far Eastern State Agrarian University was used as the research object. The research materials were sterilized according to the methodology of N.I. Vavilov All-Russian Institute of Plant Genetic Resources with some modifications. Several products were used as chemical agents for sterilization in the following sequence: a 5% solution of surfactants, fungicide Fundazol, EC (1 g/l), the bleaching agent ACE freshly diluted with distilled water in the proportion 1:9 (0.50% of NaOCl in the working solution), and 70% ethanol. The primary explants were cultured on an MS containing 20 g/l sucrose and 6 g/l agar (hereafter – MS) and supplemented with 6-benzylaminopurine (BA) at a concentration of 0.5 mg/l. The pH of the medium was adjusted to 5.7-5.8 using 1N КОН. The explants (microcuttings with one-two internodes) were subcultured on an MS supplemented with BA (0.5 mg/l). The morphometric parameters of the plants were measured on the 35th day of cultivation. The sterilization of the explants with Fundazol (1 g/l) and the ACE diluted with distilled water in the proportion 1:9 allowed us to obtain a high number of viable microclones (50%). The elimination of leaves from the honeysuckle microcuttings drastically decreased the survival rate and led to the death of the microclones in most cases (the mortality rate was 98.7 %). Subculturing the microcuttings on the MS supplemented with BA at a concentration of 0.5 mg/l facilitated the normal growth and development of the regenerated honeysuckle plants (the average reproduction rate was 4.65).

Agronomic character and productivity of improved Acehnese rice lines under upland cultivation system

The improvement of Sigupai has been conducted by inserting Sd-1 gene into its progenies resulting in a shorter lifespan and higher productivity. Through this improvement process, a number of new lines have been produced. However, the adaptataion ability of these lines when cultivated under an upland cultivation system is unclear. The purpose of this research is to determine the agronomic character and productivity of these improved lines under upland cultivation system. The research was conducted at Experimental Garden and Plant Breeding Laboratory, Agriculture Faculty, Universitas Syiah Kuala from March to July 2023. The experimental design used in the research was a non-factorial randomized block design (RBD) consisting of 7 new improved lines, T5.3.12.1.3.12; T5.3.12.1.5.2; T9.1.7.6.9.12; T9.6.1.6.12.1; T9.8.8.3.5.9; T29.2.11.10.7.2; T29.8.5.2.12.12 with 3 replications. The parameters observed were plant height, number of tillers, panicle length, flowering time, harvest time, the weight of filled grains per hill, the weight of 1000 grains, and estimated production per hectare. Research results showed that the lines had significant differences on plant height at 4,6, and 8 week after transplanting (WAT) and at harvesting time, the number of tillers at 4,6, and 8 WAT and weight of 1000 grains. The lines T5.3.12.1.3.12 and T5.3.12.1.5.2 were prospective for upland cultivation with a plant height <110 cm, harvesting time <125 day after sowing (DAS), and estimated production 5.28- 6.03 tons ha−1.

Effect of eco-enzymes on vegetative and generative growth in several kipas putih soybean (Glycine max (L) Merr.) mutant lines

This research used soybeans resulting from gamma-ray radiation mutations of the Kipas Putih variety to obtain new superior varieties that are better than their parents. The research was carried out at the East Sector 2 Experimental Garden, as well as the Genetics and Plant Breeding Laboratory, Faculty of Agriculture, Syiah Kuala University from April to July 2023. This research used a Randomized Completely Block Design (RCBD) in a 2 x 4 factorial pattern with 3 replications so that there are 24 experimental units. The first factor is the concentration of ecoenzyme (K) which consists of 2 levels (without eco-enzyme and 10 ml L−1), while the second factor was the soybean line which consists of 4 levels, namely mutants B4, B7, B18, and the Kipas Putih (parent) variety. The results showed that the application of 10 ml L−1 eco-enzyme had an influence on the parameters of plant height, number of productive branches, number of pods, number of pithy pods, and percentage of pithy pods. The Kipas Putih G1 (B4) soybean mutant line was the best in terms of the number of pithy pods. The Kipas Putih G2 (B7) soybean mutant line was the best in the parameters of harvest age, flowering age, number of pods, and seed weight per plant. The best interaction of eco-enzyme with mutant lines was found in mutant lines G3 (B18) and G2 (B7) when given 10 ml L−1 of eco-enzyme based on the parameters of the number of productive branches and seed weight per plant.

Entrepreneurial Prospects of Animal Breeding and Genetics: The Perspectives of Undergraduates in Two Nigerian Universities

The study explored the entrepreneurial prospects of animal breeding and genetics from the viewpoints of undergraduates at two Nigerian institutions. The study looked at how undergraduates perceive the potential for entrepreneurship in the fields of animal breeding and genetics; it determined whether they intend to pursue entrepreneurship in any of the identified fields of the discipline; and examined the relevance of the curriculum to the entrepreneurship knowledge needed to succeed in the fields; and identified the difficulties that these undergraduates might face in their entrepreneurial intention endeavors. The study adopted a qualitative methodology to explore the entrepreneurial prospects of animal breeding and genetics from the viewpoints of undergraduates at two Nigerian institutions. 30 undergraduate students from two universities were taken to represent the sample for the study. An open-ended survey created on Google form was used for the collection of data. The link of the Google form was sent to the students’ platform in the Department of Animal Genetics in the two selected universities. The findings demonstrated that Animal Breeding and Genetics undergraduate students perceive the potential for entrepreneurship in animal breeding and genetics to be numerous including setting up animal clinic, animal breeding laboratory, establishing a poultry business, setting up a consultancy outlet on animal breeding and genetics, among others. Majority of the undergraduate students indicate their intention to pursue entrepreneurship in animal breeding and genetics instead of looking for the white-collar jobs. Furthermore, the current curriculum in Animal Breeding and Genetics in the two universities are very relevant to the fields and the knowledge they have gathered so far is enough to succeed if taking into entrepreneurship after the completion of the bachelor’s degree programme. The challenges envisaged by the respondents include lack of initial capital to setting up entrepreneurship business in Animal Breeding and Genetics, cooperation, understanding and support from parents and family members, government policy including registration of the business, among others. Data and information gathered through the administration of the open-ended survey was analysed thematically following the objectives of the study. The study drew it conclusion based on the findings from the study and also makes appropriate and relevant recommendations.

Disgestive enzyme profile of jelawat fish larvae (Leptobarbus hoevenii, Bleeker 1851)

The ability of fish larvae to digest the appropriate type of feed can be seen through enzymatic activity. The digestive tract contains active enzymes including amylase, lipase and protease. This research was conducted at the Fish Hatchery and Breeding Laboratory, Faculty of Fisheries and Marine, Riau University and sample analysis at the Nutrition Laboratory, Bogor Agricultural Institute. The research aims to evaluate the ability of jelawat fish larvae (Leptobarbus hoevenii) to digest external feed through digestive enzymes. Newly hatched larvae are reared in fiber tanks measuring 2x1x0.5m with a density of 10,000 individuals, volume 1000 L. In rearing containers, larvae from 2 to 6 days old are given artemia food, starting from 7 days old they are given artificial F0 food. Feed was given twice a day in the morning and evening ad libitum. Observations were made on 0 day old larvae (D-0), (D-1) – (D-4), (D-6) and (D-8). Observation of protease, amylase and lipase enzyme profiles was carried out by sampling 1 gram of larvae. The results of observations on the activity of amylase, lipase and protease enzymes in jelawat fish were positively correlated with larval growth. Digestive enzyme activity increases when the larvae receive food from outside the body.

The effect of banana peel flour (Musa paradisiaca) as additional feed raw materials for common carp (Cyprinus carpio)

Banana peel flour has a high nutritional content and can be used as a raw material for fish feed. The study was to find out the effect of banana peel flour as a raw material for feed on enhancing common carp fish growth. The study was conducted from February to April 2023 at the Fish Hatchery and Breeding Laboratory, Faculty of Marine and Fisheries, Universitas Syiah Kuala. The experimental group used a CRD with 5 treatments and 3 replications. The treatments included T0 (0%), T1 (2.5%), T2 (5%), T3 (7.5%), and T4 (10%) doses of additional Kepok banana peel flour. The sample fish used were an average weight of 1.64 ± 0.24 g fish.-1, which was cultured for 40 days. The parameters observed included survival, growth rate, and feed conversion ratio. The results revealed that adding Kepok banana peel flour as a raw material for common carp feed had a significant influence on absolute weight growth, specific growth rate, and feed conversion ratio (P&lt;0.05), but had no effect on survival (P&gt;0,5). The optimal percentage obtained was the addition of 7.5% banana peel flour in the feed formulation (T3) which was able to produce 1.73 ± 0.12% day-1 SGR. Hence, the addition of Kepok banana peel flour as a feed raw material is quite effective in supporting the growth of common carp.

Enhancement of growth and survival rates in asian redtail catfish (Hemibagrus nemurus CV) larvae with probiotic soaking technique

One of the freshwater fish commodity has a high economic value is Asian redtail catfish. However, the Asian redtail catfish growth relatively slow between larvae stage until fry stage. The solutions for this problem is giving probiotics that can be increase the growth of fish larvae. The aimed to analyse the effect of immersion on Asian redtail catfish larvae in probiotics to improve growth and survival rate. This study was conducted between May until July 2024 at the Laboratory of Fish Hatchery and Breeding, Faculty of Fisheries and Marine, Riau University. This study used a completely randomized design with immersion treatment using the probiotics trademark raja siam at different dose, namely 0 ml/L, 1.5 ml/L, 2.0 ml/L, and 2.5 ml/L. Based the results of study shown that the best dose of immersion on Asian redtail catfish larvae using probiotics was in 2.5 ml/L, the absolute weight growth at 9.7818 g, absolute length growth at 9.03 cm, specific growth rate at 11.91%/day, cannibalism type A, B were 2.00%, 0.00%, cannibalism index 2.00%, normal mortality 5.33% and survival rate 92.67%.

Current trends in directed work on production of rabbit breeding products

Today, the meat industry is making great strides developing both in terms of quality raw materials and quantity. The task is to provide the population of the country with full-fledged protein of animal origin and rabbit meat has no equal in this: rabbit meat is a dietary product favorably differing from other species. To date, we have not satisfied market for 300 thousand tons of rabbit meat and it is understandable - the product market is in the stage of formation. In this regard, the task of creating a highly productive rabbit, not inferior in its performance to analogues, is very relevant. Scientists of Belgorod State Agricultural University since 2013 are engaged in the breeding process, which continues to this day, which is highly relevant for the development of food cluster Belgorod region. The result of work is a highly productive rabbit of own selection of meat direction of productivity. The main zootechnical parameters of the rabbit: slaughter yield 60-65%, average daily gain in the stage of active growth - 45g. Slaughter indicators rabbit own selection shows at the age of 3 months in the range from 2900-3800g. That is significant in breeding for live weight. \ In the conditions of the laboratory of rabbit breeding, we get 6 births per year. As a result of systematic selection work aimed at growth energy, milkiness in rabbits and dermis white color we have a rabbit with a given phenotype, live weight of male producers over 8 months of age on average - 4,8-5,8 kg, rabbits - 4,7-5,5 kg. 2023-2024 years according to the technological map of the breeding process - stabilization and consolidation in the offspring of the obtained economically useful characteristics.

Effect of herbal leaf extract on Oreochromis niloticus immunity infected with Streptococcus agalactiae

Streptococcosis disease caused by the pathogen S. agalactiae is a serious problem in freshwater fish farming. This research aims to use multiherbal ingredients to stimulate the improvement of the fish's immune system in fighting infection by the pathogenic bacteria S. agalactiae. The research was carried out at the FKIP Chemistry Laboratory, the Fish Hatchery and Breeding Laboratory of the FKP, and the Laboratory of the Faculty of Medicine, Syiah Kuala University. The test fish used were tilapia measuring 7-8 cm length. The research method was carried out experimentally using a Completely Randomized Design consisting of 5 treatments and 3 replications, namely treatment A (negative control), B (positive control), C (addition of C. gigantea), D (addition of M. oleivera), E (addition of C. alata L). The test result data is analyzed using Analysis of Variance. The results of research on immersion in multiherbal extracts in fish infected with S. agalactiae showed an increase in the immune response as seen in blood parameters (leukocytes, hemoglobin, hematocrit) and a higher survival rate compared to those without immersion in the extract. The highest survival rate was obtained in the treatment of 10 ppm of C. alata L leaves extract at 83.33%.

Growth intensity of young rabbits on the background of use of complete mixed fodders

The development of each individual is influenced by many factors: from genetic to environmental conditions. Therefore, the goal of our research was to establish the characteristics of the growth rate of rabbits from birth to sale when using complete feed in a controlled microclimate. Research was carried out on complex crossbreeds in the rabbit breeding laboratory of the Belgorod State Agrarian University. At birth, the average live weight is 53±2 g. In the first three days, the rabbits were fed colostrum and their average daily gain was 8±1 g, when switching to milk in the next 4 days it increased to 13±1 g, and in the next week - 19±2 g. In the third week of life, the rabbits were introduced to the feed; during this period, the average daily gain did not increase significantly and amounted to 21±3 g. From the next week, the feed began to prevail in the diet of the young animals, and their average daily gain increased to 39±4 g, and the live weight reached 796±43 g. Starting from the 30th day, the rabbits were exposed to stress factors such as branding and weaning. At the same time, the average daily increase in live weight continued to increase, reaching a maximum in the interval between 50 and 60 days with values of 40-42 g, regardless of the method of preventing eimeriosis. It is worth noting that live weight when using a coccidiostat based on essential oils (Ent-Oil Eimecon Dry) is higher than when using a broad-spectrum antibiotic effective against eimeria (Cycocin) and amounted to 3078±38 and 3305±62 g, respectively (p &lt; 0.01).

Directed work on breeding of high-blooded rabbit litters in the rabbit breeding laboratory of Belgorod GAU

The rabbit is one of the most common types of laboratory animals used in a number of experimental studies in general biology, medicine and veterinary medicine. And today, the most actively discussed strategy is the policy of import substitution as a factor in ensuring the growth of domestic agribusiness, and of course rabbit breeding is the most promising and rapidly developing industry. Therefore, we believe that the creation of crossbred rabbits of domestic selection that are not inferior in their characteristics to their European counterparts is an extremely urgent task, which served as the driver for the development of the issue of creating a highly productive herd of rabbits (high-blooded crossbreeds) in a relatively short time: until 2024. It should be noted that the selection process began in 2013 and systematically developed until the present time, when it became obvious and relevant for the development of the food cluster of the Belgorod region, including the work on the creation of a specialized, fully adapted line of rabbits. As a result of systematic selection work aimed at growth energy, milk production in rabbits and white dermis, we have a rabbit with a given phenotype (white color with a thickness of 9-15 microns in the area of the withers of the epidermis, dermis -250-350 microns, in accordance with the requirements for the production of resorbing membranes from dermis of rabbits for the dental industry), the live weight of male sires over 8 months of age on average is 4.8-5.8 kg, female rabbits - 4.7-5.5 kg. Today, the obtained economically useful characteristics are being stabilized and consolidated in the offspring.

The EFFECT OF ADMINISTRATION OF PAITAN (Tithonia diversifolia) LIQUID EXTRACT ON THE GROWTH OF TISSUE CULTURAL PRODUCTS OF BARANGAN BANANA (Musa acuminata L.) SEEDLINGS

Bananas (Musa spp.) are tropical plants that are very popular in Indonesia. Banana plants in the nursery require a planting medium that contains the nutrients the plants need. Tithonia is an annual weed that is suitable for use as a source of plant nutrients. This research aims to determine the effect of giving Tithonia liquid extract on the growth of Barangan banana seedlings resulting from tissue culture at the seedling stage and the best dose for using Tithonia liquid extract. This research was conducted at the Germplasm Nursery and Breeding Laboratory of the Tropical Fruit Plant Research Institute, Solok, West Sumatra, from September to December 2020. This research used the RAL method (Completely Randomized Design) with four treatments and six replications, in the form of 1) Without Tithonia extract, 2) Giving 1 ml of Tithonia extract, 3) Giving 2 ml of Tithonia extract, and 4) Giving 3 ml of Tithonia extract. The parameters observed were plant height, number of leaves, leaf length, leaf width, and stem diameter. Data was tested statistically. If calculated F &gt; F table then it is tested further using the Duncan Multiple Range Test (DNMRT) with a level of 5%. The results of the research showed that giving Tithonia liquid extract had an effect on the growth of Barangan banana seedlings resulting from tissue culture. Significantly different results were obtained for the leaf width increase parameter. On the other hand, the results were not significantly different for other parameters such as plant height, number of leaves, leaf length and stem diameter. Giving 1 ml of Tithonia liquid extract was the best dose in this study.

THE INFLUENCE OF FOLIAR FERTILIZATION ON THE YIELD AND QUALITY TO SOYBEAN

This experiment investigated the effect of foliar fertilization on yield components, yield and protein content to 75 soybean genotypes from four maturity groups. The experiment took place within the Soybean Breeding Laboratory at Research and Development Station for Agriculture Turda (RDSA Turda) over the course of two years (2020, 2021). The experimental design was a complete randomized block with three replications in which three variants of fertilization were analyzed, and the application of foliar fertilizers was carried out in different stages of soybean vegetation. In general, if we refer to the yield, it is observed that most of the genotypes that reacted favorably to the application of foliar fertilization are with the Ff1 variant, on the other hand, for the protein content, it seems that the Ff2 foliar fertilization variant causes an increase in protein in most of the genotypes that they had a favorable reaction to foliar fertilization. Regarding the component elements of yield, the application of foliar fertilization variants does not greatly contribute to increasing their number, being directly related to the genotype but also the interaction between environment x genotype.

THE EFFECT OF DIFFERENT WATER LEVELS ON THE GROWTH AND SURVIVAL RATE OF CACHAMA (Colossoma macropomum) LARVAE

The study was conducted from March to May 2022 at the Fish Hatchery and Breeding Laboratory of the Fishery and Marine Science Faculty, Universitas Riau. This research aimed to determine the effect of the best water level on the growth and survival rate of cachama larvae (Colossoma macropomum). This study used a factorial completely randomized design (CRD) with four treatments and three replications. The treatments used were P1 = water level 5cm, P2 = water level 10cm, P3 = water level 15cm, and P4 = water level 20cm. Larvae were reared for 40 days with a stocking density of 2 fish/L. Different water levels showed a significant effect on the growth of absolute weight, absolute length, and specific growth rate of cachama larvae and no effect on the survival of cachama larvae (p&lt;0.05). The best treatment was at a water level of 5 cm, with absolute growth of 1.73 g, absolute length of 4.59 cm, specific growth rate (SGR) of 17.16%/day, and survival rate of 91.11%. Water quality parameters during the study were temperature ranging from 26.7-28.4℃, pH 6.0-6.9, and dissolved oxygen ranging from 5.2-5.9 mg/L

The Effect of the Depth of Soil Moisture on the Growth and Development of Cherry Seedlings

Background: For the first time in the conditions of the Volgograd region, new knowledge was obtained, which made it possible, taking into account the changes in the morphology of the root system occurring during the formation of seedlings, the orientation of physiological processes and the biological needs of plants for their optimization, to justify a differentiated water-saving drip irrigation regime in combination with fertilizing vegetating plants, providing high-quality annual sweet cherry seedlings with high economic and water-saving efficiency, environmental tolerance. Methods: The experimental part of the work was carried out in the laboratory of breeding, seed production and nursery breeding 2017-2021 years. The productivity of the variety-rootstock combination was calculated relative to biometric parameters: crown projection area (S), crown volume (V), stem cross-sectional area (S). Result: In the course of the work, methods of watering stone crops, in particular cherries and their effect on survival, growth and development of seedlings in the nursery were studied. The scheme of experiments provides for an assessment of the influence of the water regime of the soil on the formation of the height of the central stem, the root system and the yield of seedlings of class 1 according to the variants of the experiment. Their values were greater than in the control, respectively, by 21 and 17 cm, 24-32%. At the same time, the yield of first-class seedlings in the third variant exceeds the second variant by 6%. According to the results of the conducted studies, the option of maintaining soil moisture at least 80% of the lowest moisture capacity during the adaptation period of the graft with a rootstock in a layer of 0.2 meters, followed by an increase in the soaking depth to 0.4 meters, proved to be the best. In the phase of the transition of seedlings to the dormant period, the pre-watering soil moisture should be maintained at least 70%.

Effect of Iron (Fe) heavy metal content at different pH on the germination of seven soybean varieties in Indonesia

Greater use of acid soil has expanded the area under cultivation for soybeans; however, acid soil is associated with heavy mineral toxicity, including Iron (Fe). This investigation looked at how well soybean seeds germinated in media containing heavy metal Fe and how the pH of the media affected the viability of soybean seeds. This research was conducted at the Seed and Plant Breeding Laboratory at the University of Lampung, Indonesia. The experimental design was a randomized block design. The first factor was seven soybean local varieties – Grobogan, Anjasmoro, Derap 1, Detap 1, Dena 1, Deja 1, and Dega 1 – and the second factor was heavy metal Fe solution pH of 6–7 and 4.5 and without heavy metal Fe (control). Seed viability in heavy metal Fe medium was assessed using radicle emergence, germination capacity or percentage, germination speed, number of normal seedlings, normal seedling hypocotyl length, main root length of regular seedlings, and normal shoot dry weight. This research found that heavy metal Fe affected soybeans’ seeds’ viability in pH 6–7 and 4.5. The observed data showed that all seeds’ viability variables in media with heavy metal Fe, both in pH 6–7 and in pH 4.5, differ from the control media. The seed viability in media heavy metal Fe pH 6–7 was not significantly different from the control media, but in pH 4.5, the difference is significant. Soybean varieties’ characteristics also influence how heavy metal Fe in different pH affects seed viability. Overall, Anjasmoro, Deja, Grobogan, and Dega were the types that consistently demonstrated resistance or adaptation to heavy metal Fe existence, while Dena, Derap, and Detap are susceptible to heavy metal Fe existence. Seed viability in Iron medium is not always related to seed physical performance; therefore, before planting soybean in acid soil, it is recommended to conduct a seed viability test.

Periodical crossing of the laboratory population with the natural population would improve fitness in S. sunia ( Lepidoptera: Noctuidae).

The research focused on evaluating the biological and reproductive parameters of the species Spodoptera sunia with the introduction of field genetic material, in the Noctuid Insect Breeding Laboratory. The experiment consisted of three treatments and three repetitions involving 30 individuals each. Field-collected S. sunia population was reared in the laboratory under semi-controlled conditions of temperature and humidity for three generations. The progeny of the third generation was crossed with the laboratory population and the resulting progeny was observed for growth and reproductive fitness. The results revealed that the hybrid progeny (T3) has a sex ratio (F: M) of 0.82, as against 1.22 and 0.76 observed in the field (T1) and lab populations (T2) respectively. The T1 females oviposited 196 egg masses as against 160 and 59 egg masses by T3 and T2 females respectively. The larval growth was more in hybrid progeny with shorter larval duration. However, no variation was observed in the incubation and pupal periods. Since the most optimal results were obtained in T2 and T3, it is recommended to introduce genetic material every six months to maintain a good laboratory population of the insect host under study and better breeding of its natural enemies.

Identification of rice blast resistance genes Pi-1, Pi-2, Pi-33, Pi-40, Pi-ta, Pi-b

Rice is a valuable crop used for food throughout the world. To develop modern, productive and disease resistant rice varieties, it is necessary to accelerate the breeding process using molecular biology methods. The purpose of the current study was to identify alleles of six blast resistance genes (Pi-1, Pi-2, Pi-33, Pi-40, Pi-ta and Pi-b) in the selected rice samples using MAS (marker-associated selection method). The objects of the study were 446 breeding rice samples sent to the laboratory of cell breeding for analysis by breeders from the laboratory for rice breeding and seed production of the FSBSI «ARC «Donskoy». Identification of genes in them was carried out differentially and was determined by the pedigree of the samples. In order to determine the alleles of the blast resistance genes Pi-1, Pi-2 and Pi-33, all 446 samples were studied, for the Pi-40 gene there were studied 20 samples, for the Pi-ta gene there were studied 316 samples. For DNA extraction, there was used a Russian-made kit ‘DNA-Extran-3’. PCR was performed using specific primers of the target genes. Identification of reaction products was performed on agarosegels after photographing in ultraviolet light. As a result of the study, there were identified the rice samples which carried from 1 to 5 blast resistance genes in various combinations. There have been identified 14 samples that possess a set of 5 resistance genes, such as 2723, 2724, 2727, 2728, 2729, 2730, 2733, 2735, 2736, 5007, 5671, 5673, 5450/2 and 2450/2. The information obtained from the results of the study could then be used by breeders to use valuable genotypes as donors in crosses, as well as to select promising breeding material resistant to blast disease.

Stand density and productivity of sainfoin

Prolonged vegetation and changes in weather and climatic conditions according to seasons and vegetation periods result in the loss of sainfoin plants and a decrease in productivity of forage and seeds. The identification of new varieties with high adaptability to the agroclimatic conditions of a particular region of their cultivation, the study of patterns of changes in various economic traits according to a year of life will allow selecting more productive and adapted lines and forms of sainfoin plants. The purpose of current paper was to present the study of plant density of sainfoin varieties and new lines during 3 years of life according to their productivity. The study was carried out in the laboratory for breeding and seed production of perennial grasses of the FSBSI Agricultural Research Center «Donskoy». The objects of study in the nursery for preliminary variety testing were 3 varieties and 6 lines of sandy sainfoin that were promising for feed and seed productivity. Conditions in the south of the Rostov region made it possible to obtain seedlings with a plant density of 309–313 pcs/m2 with a field seed germination rate of 75.2–80.2 %. In the second year of sowing, the plant stand density varied from 198 pcs/m2 to 251 pcs/m2. With such plant density there has been formed a dry mass yield of 6.41–7.17 t/ha. In the third year, the plant density compared to the previous year decreased significantly and varied from 109 pcs/m2 to 127 pcs/m2, while the dry mass yield was formed at 6.25–7.13 t/ha. The number of gen erative shoots in the studied varieties and lines varied over the years from 981 pcs/m2 to 1244 pcs/m2 in the second year, while the seed productivity of the best lines was 0.90–0.95 t/ha, and from 415 pcs/m2 to 525 pcs/m2 in the third year of life, while the best lines had a seed yield of 0.85–1.09 t/ha.

Study of the heterosis effect of morpho-biological traits of grain sorghum hybrids F&lt;sub&gt;1&lt;/sub&gt;

The priority direction in grain sorghum breeding is the development of new early maturing, highly productive hybrids adapted to the soil and climatic conditions of the region and their introduction into agricultural production. Thus, the use of the heterosis effect in hybrids developed from maternal lines with cytoplasmic male sterility is of particular interest. The current paper has presented the study results of heterosis of grain sorghum hybrids of the first generation, developed on the basis of CMS lines, according to the main quantitative traits. The trials were carried out in the laboratory for grain sorghum breeding and seed production of the FSBSI «Agricultural Research Center «Donskoy» in 2020–2022. The purpose of the current research was to study the heterosis effect of morpho-biological traits of grain sorghum hybrids of the first generation developed from crossing sterile lines with highly productive varieties and samples of various breeding. In most hybrids, true and hypothetical heterosis were identified according to plant height, weight, and number of grains per panicle, and the frequency of high heterosis values was estimated according to weight and number of grains. The maximum effect of heterosis manifestation was established based on the trait ‘protrusion of a panicle stalk’ in the combination of AZSK21 x ZSK 24/20 (Htrue = 335.0 %; Hhyp = 694.4%). According to the length of a vegetation period during 2020–2022, all combinations turned out to be early maturing and the heterosis effectwas absent in most variants. 65 % of hybrids were classified as undersized, and the highest heterosis in the trait ‘plant height’ was 38.9 %. During the trials, the hybrid ‘Jetta x ZSK 217’ (87.35 g) showed an excess in the trait ‘grain weight per panicle’ over the best parental form. There have been identified the samples that are expedient to use in crossings to obtain highly productive hybrids, such as ‘By 112’, ‘ZSK 196/17’, ‘ZSK 217’, ‘Zhemchug № 56’, ‘Zhemchug № 59’ and ‘B-10434’.