Changes in the content of proteins and lipids and in the state of the antioxidant system in mutant forms of <i>Amaranthus cruentus</i> L.

Background. One of the important indicators of the nutritional value of amaranth is the high content of protein and lipids in seeds. Hence, obtaining and identifying such forms of amaranth through breeding, so that they also possessed resistance to abiotic stressors, is an important task.Materials and methods. Leaves and seeds of Amaranthus cruentus L. and mutants of the second inbred generation obtained by treatment with sodium azide were analyzed. The Bradford assay was used to measure the content of total soluble protein, lipid analysis was performed by thin-layer chromatography, the state of the antioxidant system was assessed according to catalase and peroxidase activities and the rate of superoxide anion formation. Mathematical data were processed using the Statistica 10.0 software.Results. The highest concentration of total protein in seeds was 13.78 mg/g in one of the mutants obtained after treatment with 3 mM sodium azide. Fifteen fatty acids were found in amaranth seeds, and in four mutants a significant increase in the percentage of omega-6 unsaturated linoleic acid was recorded. An increase in salt tolerance compared to the control was observed in mutants No. 2 and No. 3. Mutant No. 2 under salinization demonstrated higher peroxidase activity and mutant No. 3 higher catalase activity; both mutants showed a reduced rate of superoxide anion formation compared to the control.Conclusion. Amaranth mutants identified for higher stress resistance, protein content and linoleic acid content can be recommended for further breeding to produce new cultivars of amaranth with economically valuable traits

Evaluation of genetic polymorphism and drought and salinity tolerance of Amaranthus cruentus L. mutants

Background. Drought and salinization are serious environmental problems in agriculture. Therefore, it is important to grow cultivated plants resistant to abiotic environmental factors in the fields. Due to its high nutritional value and adaptation to diverse environmental conditions, amaranth is considered a promising crop for cultivation, including in arid zones. In connection with modern climate change, the urgency of breeding more stressresistant amaranth varieties is increasing.The purpose of the study is to assess the genetic diversity and stress resistance of mutant forms of red amaranth Amaranthus cruentus L. obtained using sodium azide. Materials and methods. Using microsatellite markers at three SSR loci, the molecular genetic polymorphism of seven mutant forms of amaranth generation M3 was evaluated. According to SSR markers GB-AM-132 and GB-AM-137, mutant plants did not differ from each other and from the wild type. Using the SSR marker GBAM-099, three alleles with three combinations of them were identified among the analyzed mutant plants. Results. According to the results of morphophysiological analysis under conditions of abiotic stress, one of the mutant lines during drought had the best indicator of the relative water content, was characterized by the highest results in terms of stem height and biomass, and in these mutants an increase in the activity of ascorbate peroxidases and glutathione-S-transferases was recorded, compared with wild type. The results obtained indicate a high drought resistance of this mutant line. Another mutant line showed high salt tolerance. Thus, under saline conditions, these mutants were characterized by an increased stem height, an increase in the total antioxidant capacity, as well as an increase in the activities of ascorbate peroxidases and glutathione-S-transferases compared to the wild type. Conclusions. Thus, as a result of our study, mutant forms of amaranth were identified that are resistant to lack of water and excessive salt content in the soil. These forms of amaranth can be used as a material for breeding of stress-resistant varieties

Agrobacterium-Mediated Transformation of Amaranthus cruentus L. Epicotils

Амарант багряный Amaranthus cruentus L. является ценной кормовой и зерновой культурой. Для получения новых сортов этого растения могут быть использованы методы генетической трансформации, однако для A. cruentus такие технологии остаются неразработанными. Данная статья посвящена описанию результатов наших работ по агробактериальной трансформации сегментов эпикотилей A. cruentus сорта «Багряный» трансгеном ARGOS-LIKE Arabidopsis thaliana L., находящимся под контролем 35S промотора в бинарном векторе pCambia 1301 с селективным геном устойчивости к гигромицину B. Для регенерации побегов из сегментов эпикотилей после агробактериальной трансформации использовали среду Мурасиге-Скуга, содержащую 13 мкM 6-бензиламинопурина и 1 мкM 1-нафтилуксусной кислоты. Для селекции трансгенных побегов амаранта в среду добавляли 10 мг/л гигромицина B. Укоренение полученных в ходе работы регенерантов проводили на селективной среде МС с добавлением 2 мкM 3-индолилуксусной кислоты. В ходе проведенной работы были получены 3 трансгенных растения амаранта багряного, несущие генно-инженерную конструкцию 35S::ARGOS-LIKE. Трансгенность полученных растений амаранта была подтверждена путем ПЦР-анализа на наличие маркерных и целевого генов. Процент эффективности агробактериальной трансформации A. cruentus при использованном нами методе составил 4 %. Два трансгенных растения удалось акклиматизировать к условиям почвы и открытого воздухаRed amaranth Amaranthus cruentus L. is a valuable fodder and grain crop. To generate new varieties of this plant, genetic transformation methods can be used, but for A. cruentus such methods remain undeveloped. The present study describes the results of our research in Agrobacterium-mediated transformation of epicotyl segments of A. cruentus variety “Bagryanyi” by the ARGOS-LIKE transgene of Arabidopsis thaliana controlled by the 35S promoter in the binary vector pCambia 1301 with a selective hygromycin B resistance gene. For shoot regeneration from epicotyl segments after Agrobacterium-mediated transformation, Murashige-Skoog (MS) medium containing 13 μM 6-benzylaminopurine and 1 μM 1-naphthylacetic acid was used. For the selection of transgenic shoots, 10 mg/L of hygromycin B was added to the MS medium. Rooting of shoots was performed on selective MS medium supplemented with 2 μM 3-indoleacetic acid. Three transgenic amaranth plants with the genetic engineering structure 35S::ARGOS-LIKE were generated. The efficiency of Agrobacterium-mediated transformation of A. cruentus was 4%. The amaranth plants transgenicity was confirmed by the PCR analysis for the presence of marker and target genes. Two transgenic plants were acclimatized to soil and open air condition