Nutritional quality of different potassium efficiency types of vegetable soybean as affected by potassium nutrition

Pot experiments were conducted in 2017, 2019, and 2020 to examine the effects of potassium nutrition on the nutritional components of vegetable soybeans with different K efficiency at immature and mature stages. Two vegetable soybean varieties with higher K efficiency and two varieties with lower K efficiency were studied in the low available K soil under the condition of no K and normal K fertilization. The results indicated that almost all nutritional components in vegetable soybean were affected by K, genotypes, inter-annual differences, and their interactions. In general, no K fertilization increased protein and amino acid concentrations but decreased oil, soluble sugar, sucrose, K, Mg, and Fe concentrations in immature and mature vegetable soybean. The sensitivity of nutritional components to K nutrition differed among varieties. For instance, K high-efficiency varieties generally exhibited higher protein and amino acid concentrations without K application. K high-efficiency vegetable soybeans are low-K tolerance varieties to isoflavones. The results of this study provide insights for high yield and quality vegetable soybean breeding against soil K deficiency.

Genome sequencing and population resequencing provide insights into the genetic basis of domestication and diversity of vegetable soybean

Vegetable soybean is one of the most important vegetables in China, and the demand for this vegetable has markedly increased worldwide over the past two decades. Here, we present a high-quality de novo genome assembly of the vegetable soybean cultivar Zhenong 6 (ZN6), which is one of the most popular cultivars in China. The 20 pseudochromosomes cover 94.57% of the total 1.01 Gb assembly size, with contig N50 of 3.84 Mb and scaffold N50 of 48.41 Mb. A total of 55 517 protein-coding genes were annotated. Approximately 54.85% of the assembled genome was annotated as repetitive sequences, with the most abundant long terminal repeat transposable elements. Comparative genomic and phylogenetic analyses with grain soybean Williams 82, six other Fabaceae species and Arabidopsis thaliana genomes highlight the difference of ZN6 with other species. Furthermore, we resequenced 60 vegetable soybean accessions. Alongside 103 previously resequenced wild soybean and 155 previously resequenced grain soybean accessions, we performed analyses of population structure and selective sweep of vegetable, grain, and wild soybean. They were clearly divided into three clades. We found 1112 and 1047 genes under selection in the vegetable soybean and grain soybean populations compared with the wild soybean population, respectively. Among them, we identified 134 selected genes shared between vegetable soybean and grain soybean populations. Additionally, we report four sucrose synthase genes, one sucrose-phosphate synthase gene, and four sugar transport genes as candidate genes related to important traits such as seed sweetness and seed size in vegetable soybean. This study provides essential genomic resources to promote evolutionary and functional genomics studies and genomically informed breeding for vegetable soybean.

Genome-Wide Variation Analysis of Four Vegetable Soybean Cultivars Based on Re-Sequencing

Vegetable soybean is a type of value-added specialty soybean, served as a fresh vegetable or snack in China. Due to the difference from other types, it is important to understand the genetic structure and diversity of vegetable soybean for further utilization in breeding programs. The four vegetable cultivars, Taiwan-75, Zhexiandou No. 8, Zhexian No. 9 and Zhexian No. 10 are popular soybean varieties planted in Zhejiang province, and have large pods and intermediate maturity. The clustering showed a close relationship of these four cultivars in simple sequence repeat analysis. To reveal the genome variation of vegetable soybean, these four improved lines were analyzed by whole-genome re-sequencing. The average sequencing depth was 7X and the coverage ratio of each cultivar was at least more than 94%. Compared with the reference genome, a large number of single-nucleotide polymorphisms, insertion/deletions and structure variations were identified with different chromosome distributions. The average heterozygosity rate of the single-nucleotide polymorphisms was 11.99% of these four cultivars. According to the enrichment analysis, there were 23,371 genes identified with putative modifications, and a total of 282 genes were related to carbohydrate metabolic processes. These results provide useful information for genetic research and future breeding, which can facilitate the selection procedures in vegetable soybean breeding.

Comparative Analysis and Development of a Flavor Fingerprint for Volatile Compounds of Vegetable Soybean Seeds Based on Headspace-Gas Chromatography-Ion Mobility Spectrometry

Evaluating the volatile compounds and characteristic fingerprints of the core cultivars of vegetable soybean would provide useful data for improving their aroma in the breeding programs. The present study used headspace-gas chromatography-ion mobility spectrometry (HS-GC-IMS) to evaluate the volatile compounds of vegetable soybean seeds at a specific growth stage. In total, 93 signal peaks were identified, 63 compounds qualitatively, with 14 volatile flavor compounds providing multiple signals. The 63 volatile compounds consisted of 15 esters, 15 aldehydes, 13 alcohols, 15 ketones, one acid, and four other compounds. The peak intensity of most of the volatile compounds varied greatly between the core cultivars. The alcohols and aldehydes determined the basic volatile flavor of the vegetable soybean seeds. Volatile flavors were determined by their respective esters, ketones, or other components. Characteristic fingerprints were found in some core vegetable soybean cultivars. Four cultivars (Xiangdou, ZHE1754, Zhexian 65018-33, and Qvxian No. 1) had pleasant aromas, because of their higher content of 2-acetyl-1-pyrroline (2-AP). A principal component analysis (PCA) was used to distinguish the samples based on the signal intensity of their volatile components. The results showed that the composition and concentration of volatile compounds differed greatly between the core cultivars, with the volatile flavor compounds of soybeans being determined by the ecotype of the cultivar, the direction of breeding selection, and their geographical origin. Characteristic fingerprints of the cultivars were established by HS-GC-IMS, enabling them to be used to describe and distinguish cultivars and their offspring in future breeding studies.

Root K Affinity Drivers and Photosynthetic Characteristics in Response to Low Potassium Stress in K High-Efficiency Vegetable Soybean

Significant variations of potassium absorption and utilization exist in vegetable soybean. Pot and hydroponic experiments were carried out to examine the characteristics of root potassium (K) affinity-associated drivers and photosynthesis in vegetable soybean (edamame) [Glycine max (L.) Merr.] with different K efficiency. Two K high-efficiency vegetable soybean genotypes (Line 19 and Line 20) and two K low-efficiency genotypes (Line 7 and Line 36) were investigated in low K and normal K conditions. The root of K high-efficiency genotypes had a higher K+ affinity associated with a higher maximum K+ uptake rate (Imax), but lower Michaelis constant for K+ absorption (Km) and lower compensation concentration for K+ uptake (Cmin). Seedlings of K high-efficiency genotypes also had higher root vigor [triphenyl tetrazolium chloride (TTC) reduction method] and greater absorbing activity (methylene blue method), especially in the low K condition. Furthermore, the root bleeding-sap rate of K high-efficiency genotypes in low K stress was 9.9–24.3% greater than that of normal K conditions, which was accompanied by a relatively higher K concentration of root bleeding-sap in contributing to K+ upward flux. The root of K high-efficiency vegetable soybean genotypes exhibited K+ high-affinity and driving advantages. Photosynthetic parameters of K high-efficiency vegetable soybean genotypes were less affected by low K stress. Low K stress decreased the net photosynthetic rate of K high-efficiency genotypes by 6.1–6.9%, while that of K low-efficiency genotypes decreased by 10.9–15.7%. The higher chlorophyll (Chl) a/b ratio with enhanced relative content of Chl a in response to low K stress might be an adapted mechanism for K high-efficiency genotypes to maintain photosynthetic capacity. Stronger root K affinity drivers associated with photosynthetic adaptability to low K stress are the key factors in determining the K high-efficiency of vegetable soybeans.

PSXV-6 The effect of ultrafine iron particles on the adaptation of the digestive system of cattle to fat diets

The aim of our study was to determine the possibility of using ultrafine Fe particles (2.2 mg/head/day) as modulators of metabolic activity when using vegetable soybean and sunflower oils in ruminant diets. The studies carried out on calves with external duodenal anastomosis (diet – grassland hay (2 kg), a mixture of concentrates (1.5 kg), corn silage (5 kg), wheat straw (1 kg), oil-3% of the dry matter of the diet). The digestibility of the nutritional components of the diet analyzed daily throughout the study period. The collection of pancreatic juice was carried out for 8 hours with an interval of 60 minutes on the 7th day, the determination of the amount and enzymatic activity of the juice carried out “incito.” Introduction of ultrafine Fe particles significantly increased the digestibility of organic matter by 38% (P ≤ 0.05) with the introduction of vegetable soybean oil, crude fat by 28.4% (P ≤ 0.05) with the introduction of sunflower oil. Additional introduction of ultrafine Fe particles significantly increased the level of pancreatic secretion when sunflower oil was introduced by 59.8%, soybean oil by 56% (P ≤ 0.05). Additional inclusion of ultrafine iron particles contributed to the decrease of lipase, protease and amylase activity by 86,8%, 37,4% and 33% (P ≤ 0,05) in the sunflower oil group, by 68,2% of lipase, by 24,6% of amylase in the soybean oil group (P ≤ 0,05). A significant increase in the level of NO-metabolites was recorded in the group receiving soybean oil by 37.5 % (P < 0.05). This study shows the potential use of ultrafine Fe particles as a mineral supplement to regulate the functional activity of digestive and metabolic processes in ruminants, which may play a positive role in increasing the bioavailability of nutritional components of diets. This research performed with financial support from the project 0761-2019-0005.

Agroekoloģisko faktoru ietekme uz reti audzētu dārzeņu ražu un kvalitāti = Influence of agroecological factors on the yield and quality of rarely-grown vegetables

Zeipiņa S. (2021) Influence of agroecological factors on the yield and quality of rarely-grown vegetables. The Doctoral Thesis. Latvia University of Life Sciences and Technologies. Jelgava, LLU 130 p. The research was carried out from 2013 to 2019 in the Institute of Horticulture (LatHort). The aim: to evaluate the influence of agroecological factors on the rarely-grown vegetables yield and quality on three morphological different species: stinging nettle (Urtica dioica L.), globe artichoke (Cynara cardunculus L. var. scolymus) and vegetable soybean (Glycine max L.). The tasks of the research: • to evaluate the growth and development of stinging nettle, globe artichoke and vegetable soybean under various agrotechnical factors and meteorological conditions; • to evaluate the influence of various agrotechnical factors and meteorological conditions on the yield of selected vegetables; • to determine and evaluate the nutritional value changes under various agrotechnical factors and meteorological conditions. Work novelty: for the first time in Latvia the investigations on the influence of agroecogical factors on stinging nettle, globe artichoke and vegetable soybean are performed. All these vegetables have high potential for the healthy human diet. Work hypothesis: ensuring suitable agrotechnical factors and reducing effect of meteorological conditions can increase studied vegetables yield and the content of biologically active compounds. Scientific actuality of work: obtained results are important and useful for commercial vegetable producers, the research gives insight in the yield formation and crop quality changes under various agrotechnical factors and meteorological conditions. The structure of the Thesis: introduction, literature review, materials and methods of the research, results and discussion, conclusions, references and appendix. Introduction. Topicality of the work is justiefied, research goal and tasks are formulated, research novelty and hypothesis are estimated. The list of author`s scientific publications on the topic of Thesis is provided. A literature review is arranged into 10 sub-chapters, where the main biological active compounds in investigated vegetables are described, as well as influence of agroecological factors on their content, the growth, development, and yield formating of vegetables is studied. Also, the biology, economic importance, nutritional value, growing conditions, and influence of agroecological factor on the growth, development, yield and content of biologicaly active compounds is described for selected vegetables. Materials and methods of the research are arranged into 5 sub-chapters, wehere the methodology of the research, meteorological conditions, measurements, methods of biochemical analyses and statistics are described. Results and discussion are arranged into 8 sub-chapters, where yield and changes of biologically active compounds are analysed for stinging nettle, globe artichoke and vegetable soybean under influence of various agroecological factors. Conclusions give answers on the tasks highlighted for promotion thesis. References consist on bibliographic description of the sources of information used. Appendix describe research materials and results. Work contains of 68 figures, 10 tables, 4 annexes and 268 bibliography items.

Evaluation of natural and epoxidized vegetable oil in elastomeric compositions for tread rubber

In the tire industry, the incorporation of natural origin oils in the development of elastomeric formulations has been one of the alternatives to reduce the use of petroleum derivatives, with a high content of toxic compounds. In this work, soybean vegetable oil was investigated as a lubricant and co-activator in sulfur-vulcanized natural rubber compounds. The soybean oil was used in its natural state and chemically modified by the epoxy ring’s introduction in its structure. In an internal mixer a standard formulation of natural rubber, five formulations replacing a conventional aromatic oil and stearic acid by vegetable oil, and a formulation without an activation system were prepared. The natural and epoxidized soybean oil was characterized chemically, and the elastomeric compositions were evaluated by mechanical and rheological analysis. The mechanical properties showed satisfactory results when vegetable soybean oil was used as a lubricant and could be a substitute for conventional aromatic oils, thus guaranteeing reduction of aromatic polycyclic content in the formulations. The crosslink degree and the rheological characteristics of the samples prepared with vegetable soybean oil were similar to the natural rubber standard sample. The formulations without the zinc oxide and stearic acid evidenced the need for activators in the vulcanization reaction, as they presented properties below standard. We verified that the epoxidized soybean oil, even when promoting better dispersion of the fillers, interfered in the crosslink formation, and consequently there was a decrease in the mechanical properties of these formulations. Finally, we indicated vegetable soybean oil as a substitute for aromatic oil and stearic acid, in the elastomeric compositions used to manufacture treads.