Molecular characterization and incidence of new tospovirus: Soybean Vein Necrosis Virus (SVNV) in Egypt

Field survey study was conducted season (2017). Soybeans and weeds were weekly sampled randomly. Thrips adults were identified and counted. Detection of the virus isolate and the natural incidence was determined using; Mechanical transmission, host range, DAS-ELISA, RT-PCR. The natural incidence thrips individuals was detected depending on the SVNV% in thrips individuals and weeds hosts. Ten thrips species were associated with soybean plants in the field. The most abundant species was T. tabaci, average 256.5 average no.of individuals, followed by F. occidentalis (142.5 average no. of individuals), then N. variabilis (86.6/ average no. of individuals). Fourteen thrips species occurred on 5 legumes field crops and 41 weed plant species within soybean field. The highest average number 40.6.of individuals were recorded on Ammi majus. While the lowest one 3.3 average no. of individuals were on Urtica urens. Only 21diagnostic plant species were susceptible to infection with SVNV. G. max and Vigna radiate, were the highest percentage of infection 80% followed by V. unguilata & N. benthamiana, 75%. Egyptian isolate of Soybean vein necrosis virus (SVNV) in this study showed a high degree of similarity and it is closely related to TSWV from Egypt (DQ479968) and TCSV from USA (KY820965) with nucleotide sequence identity of 78%. Four thrips species transmitted SVNV (F. fusca 4.0%, F. schultzei 4.3%, F. tritici 3.3% and N. variabilis 68.0% transmission). Both C. phaseoli and M. sjostedti can acquire the virus but unable to transmit it. The following species; T. tabaci, F. occidentalis, S. dorsallis and T. palmi cannot acquire or transmit SVNV. The incidence of SVNV in the field started by the end of July then increased gradualy from 12.7 to 71.3% by the end of the season. In conclusion, few thrips individuals invaded soybean crops are enough to transmit high rate of SVNV within the crop. Furthermore, several vector species are also abundant on weeds, which are the major sources of soybean viruses transmitted to the crops. This information might be important for control and reduce the incidence of SVNV infection.

Soya Bitkisinin Gelişiminde Gübre, Kompost, Mikoriza ve Bakteri Uygulamalarının Etkileri

One of the most important factors that increase soil fertility is the amount of soil organic matter. One of the ways to increase soil organic matter is the addition of organic fertilizers. Yemsoy soybean cultivar was used in the study, and pot study was carried out in 3 replications according to the randomized blocks experimental design. In the study, three different fertilizer doses (EC 0- 0.5- 1), three different grape pomace compost (0- 20-40 %) were applied to the peat perlite mixture, and mycorrhiza and bacteria inoculation to these environments. At the end of a 60-day growing period, the plants were harvested from the top of the pot, and measurements were made. In the study, there was an increase in the above-ground fresh and dry weights, root fresh, and root dry weights of soybean plants grown with increasing fertilizer rates. The addition of compost to the growing medium, the addition of mycorrhiza, and bacteria caused different results in the investigated properties. The increase in compost and plant nutrition doses was effective in increasing plant growth.

Bidirectional lncRNA Transfer between Cuscuta Parasites and Their Host Plant

Dodder species (Cuscuta spp.) are holoparasites that have extensive material exchange with their host plants through vascular connections. Recent studies on cross-species transfer have provided breakthrough insights, but little is known about the interaction mechanisms of the inter-plant mobile substances in parasitic systems. We sequenced the transcriptomes of dodder growing on soybean hosts to characterize the long non-coding RNA (lncRNA) transfer between the two species, and found that lncRNAs can move in high numbers (365 dodder lncRNAs and 14 soybean lncRNAs) in a bidirectional manner. Reverse transcription-polymerase chain reaction further confirmed that individual lncRNAs were trafficked in the dodder–soybean parasitic system. To reveal the potential functions of mobile transcripts, the Gene Ontology terms of mobile lncRNA target genes were predicted, and mobile dodder target genes were found to be mainly enriched in “metabolic process”, “catalytic activity”, “signaling”, and “response to stimulus” categories, whereas mobile soybean target genes were enriched in organelle-related categories, indicating that specific mobile lncRNAs may be important in regulating dodder parasitism. Our findings reveal that lncRNAs are transferred between dodder and its host soybean plants, which may act as critical regulators to coordinate the host–dodder interaction at the whole parasitic level.

Modulation of GmFAD3 Expression Alters Abiotic Stress Responses in Soybean

Fatty acid desaturases (FADs) are a class of enzymes that mediate desaturation of fatty acids by introducing double bonds. They play an important role in modulating membrane fluidity in response to various abiotic stresses. However, a comprehensive analysis of FAD3 in drought and salinity stress tolerance in soybean is lacking. We used Bean Pod Mottle Virus (BPMV)-based vector for achieving rapid and efficient overexpression as well as silencing of Omega-3 Fatty Acid Desaturase gene from Glycine max (GmFAD3) to assess the functional role of FAD3 in abiotic stress responses in soybean. Higher levels of recombinant BPMV-GmFAD3A transcripts were detected in overexpressing soybean plants. Overexpression of GmFAD3A in soybean resulted in increased levels of jasmonic acid and higher expression of GmWRKY54 as compared to mock-inoculated, vector-infected and FAD3-silenced soybean plants under drought and salinity stress conditions. FAD3A overexpressing plants showed higher levels of chlorophyll content, efficient photosystem-II, relative water content, transpiration rate, stomatal conductance, proline content and also cooler canopy under drought and salinity stress conditions as compared to mock-inoculated, vector-infected and FAD3-silenced soybean plants. Results from the current study revealed that GmFAD3A overexpressing soybean plants exhibited tolerance to drought and salinity stresses. However, soybean plants silenced for GmFAD3 were vulnerable to drought and salinity stresses.

Soybean productivity in the Northern forest-steppe of the Tyumen region, depending on agrotechnical techniques

The solution to the problem of feed protein deficiency is possible with an increase in acreage and the selection of agrotechnical methods of soybean cultivation, taking into account the conditions of the natural and climatic zone. One of the main elements of the farming system that allows to increase the yield of soybeans is rational basic tillage, its depth depending on the type of soil, providing favorable conditions for plant growth and development, which has not been studied in the northern forest-steppe in the Tyumen region. The purpose of the work was to study the influence of agrotechnical techniques on soybean productivity in the northern forest-steppe in the Tyumen region. During the research the influence of basic tillage and its depth on agrophysical (soil density, reserves of productive moisture), agrochemical soil parameters, uniformity of sowing depth, germination and preservation of soybean plants has been established. The contamination of crops, the species composition of weeds, and the degree of contamination during soybean cultivation by basic tillage with the use of herbicide during the growing season has been studied. It has been found that the highest level of profitability of 39,7 % was achieved with the differentiated method of tillage, with the mouldboard plowing (20–22 cm) it was less by 7,2 %, with the subsurface tillage (20–22 cm) it was less by 19,3 %. The decrease in the depth of processing leads to the decrease in the level of profitability by 4,0 % with the mouldboard plowing, by 2,2 % with the subsurface tillage and by 7,4 % with the diff erentiated method. With zero tillage, the profitability level was below control by 14,6 %. Thus, the most cost-effective was the differentiated method of tillage (20-22 cm) with the profitability level of 39,7 % and a profit of 9765 rubles/ha.

Growth and Yield of Soybeans in Various Growing Media Composition and Inoculation of Rhizobacteria on Marginal Soils

Soybean is one of the leading commodities that is being developed in Indonesia. Today, the increase of soybean needs is not followed by its production capacity. Meanwhile, the area of productive land for soybean farming is decreasing due to land conversion for non-agricultural needs. One effort that can be an alternative is using marginal land by applying appropriate technology such as manure and biofertilizer. So that, it was necessary to know the composition of manure and biofertilizer, which was appropriate to increase the growth and yield of soybean plants on marginal soils. Complete Randomized Design was used in the experiment with two factors. The first factor was the ratio of manure: soil (v:v) there are 0:1, 1:1, 1:2, and 2:1. The second factor was rhizobacteria inoculum, which included without rhizobacteria, exogenous rhizobacteria, and indigenous rhizobacteria. Results showed that the composition of the best planting medium for growth and yield of soybean is manure: soil 1: 1 and 1: 2. The source of the rhizobacteria inoculum is not a significant difference to the soybean’s growth and yield. Manure and soil 1: 2 with indigenous inoculum tended to produce the best total number of nodules and effective root nodules. Manure and soil 1:1 with indigenous inoculum produce the best of seeds number. Manure and soil 1:2 or 2:1 with exogenous inoculum tended to produce the best seed index weight (g per 100 seeds).

The Arbuscular Mycorrhizal Fungus Rhizophagus Clarus Improve Physiological Tolerance to Drought Stress in Soybean Plants

Soybean (Glycine max L.) is an economically important crop worldwide. However, increasingly long periods of drought have reduced the productivity of this crop. Studies have shown that inoculation with arbuscular mycorrhizal fungi (AMF) provides a potential alternative strategy for mitigating drought. In the present study, we measured the physiological and morphological performance of two soybean cultivars under drought in symbiosis with Rhizophagus clarus. Soybean plants Anta82 and Desafio, were grown in pots previously inoculated with R. clarus. Water deficit (WD) was imposed at the V3 development stage and maintained for 7 days. A control group was performed in parallel with well-irrigated plants in the absence of R. clarus in a greenhouse. Three and seven days after the WD imposition the analysis were performed. Cultivar Anta82 showed a higher percentage of colonization, N and K leaf content, whereas Desafio, showed higher water potential, water-use efficiency under WD, and thermal dissipation that allowed higher values for Fv/Fm, A, and PH under WD+AMF. The Principal Components Analysis results were able to demonstrate that both cultivars in water deficit with AMF colonization clustered together with well-watered plants. These findings suggest that AMF had an effect on plants in order to reduce drought physiological impairment.

Effects of the Soil Moisture Content on the Superoxide Anion and Proline Contents in Soybean Leaves

Background: As an important source of feed protein, soybean is involved in the processing industry, food industry and other fields. Therefore, in recent years, the demand for soybean has increased and soybean planting areas have also increased. However, frequent droughts have a serious impact on soybean yield. Methods: During the flowering period, the soybean plants were subjected to drought treatments of different degrees (0-7 days without water). The superoxide anion and proline contents in the leaves were determined. Then, fitting curves were drawn between the soil moisture content and the superoxide anion and proline contents. Result: The effects of different soil moisture contents on the superoxide anion and proline contents in soybean leaves and the correlation between these contents were analyzed. According to the fitting curves, with a decrease in the volumetric water content of soil, the superoxide anion and proline contents in soybean leaves increased. The superoxide anion contents in drought-tolerant cultivars were significantly lower than those in drought-sensitive cultivars and the proline contents were significantly higher in drought-tolerant cultivars than those in drought-sensitive cultivars. The superoxide anion content in soybean leaves was positively correlated with the proline content in the soil volumetric water content range of 31.5% to 14.5%.

In vitro regeneration of soybean (a review)

This is an overview of contemporary published works dedicated to the ability of soybean plants to regenerate in vitro and the techniques to achieve high regeneration rates, which is a necessary condition for the inclusion of soybean genotypes in genome editing programs. The main factors that determine the regenerative capacity of explants from various soybean accessions are considered. The greatest effect on the efficiency of regeneration is exerted by the conditions of in vitro culture initiation, type of explant, composition of the nutrient medium, shelf life of seeds, and genotypic characteristics of soybean accessions.