The Effect of the Application of Stimulants on the Photosynthetic Apparatus and the Yield of Winter Wheat

The use of stimulation preparations seems to be a promising means for mitigating the effects of abiotic and biotic stressors. Their significance includes plant organism stimulation and metabolism optimisation, water regime, and nutrition during periods of stress. They help bridge it over and create conditions for rapid regeneration. In a field experiment, the effect of the application of stimulation preparations on cultivars Triticum aestivum L. with different genetic composition was evaluated (donor of blue aleurone colour KM-72-18; donor of a multi-row spike (MRS) KM-94-18). Our results show a predominantly positive effect of the application of stimulants on the yield and thousand-grain weight (TKW). The results obtained were influenced by the year, based on different temperatures and precipitation. Higher yields were achieved in 2020 with higher total precipitation during the grain filling period and with a higher maximum quantum yield of the photosystem II (Fv/Fm). In 2019, this period was significantly dry and warm, which was reflected in a lower yield and TKM, higher proline content in the leaves, and lower Fv/Fm values. In both experimental years, there was a higher yield of the cultivar with blue aleurone (KM-72-18). In the case of cultivars with coloured grains, the promising use of the content substances in cultivars as natural means of increasing resistance to abiotic and biotic stressors seems to be promising.

Yield Load Solutions for SE(B) Fracture Toughness Specimen with I-Shaped Heterogeneous Weld

The objective of this work was to investigate the fracture behavior of a heterogeneous I-shaped welded joint in the context of yield load solutions. The weld was divided into two equal parts, using the metal with the higher yield strength and the metal with the lower yield strength compared to base metal. For both configurations of the I-shaped weld, one with a crack in strength in the over-matched part of the weld and one for a crack in the under-matched part of the weld, a systematic study of fracture toughness SE(B) specimen was carried out in which the crack length, the width of the weld and the strength mismatch factor for both weld metals were varied, and the yield loads were determined. As a result of the study, two mathematical models for determination of yield loads are proposed. Both models were experimentally tested with one strength mismatch configuration, and the results showed good agreement and sufficiently conservative results compared to the experimental results.

Influence of basic tillage systems on economic efficiency of soybean cultivation

Soybeans have become widespread in the world crop production as a valuable oilseed and high-protein crop with a unique biochemical composition. In the Russia in 2015-2019 annually there is an increase in acreage, yield and gross yield of soybeans. The research purpose is to substantiate the most effective system of basic soil cultivation during the soybeans cultivation in the Samara region. The research tasks included: to study the peculiarities of the soybeans yield formation depending on the main tillage systems, to evaluate the economic efficiency of the main tillage systems. It was found that the basic tillage system provided the best conditions for the formation of the soybean in 2018-2019. Thus, the highest yield was obtained in the variant with plowing by 20-22 cm and amounted to 14.9 cwt/ha, the lowest in the variant without autumn mechanical tillage - 10.1 cwt/ha. The calculation showed that the soybeans cultivation in all variants was effective. Direct costs in the soybeans cultivation varied according to the studied options from 15879.28 rubles/ha to 17767.34 rubles/ha, the cost price - from 1192.4 rubles/cwt to 1572.2 rubles/cwt. The basic tillage system with elements of minimization reduced direct costs, however, due to the lower yield, the highest net income was obtained in the variant with plowing by 20-22 cm and amounted to 19482.7 rubles/ha, with a profitability of 109.7%.

Evaluations of All-in-One, Polycarboxylate-Based Superplasticizer with Viscosity Modifying Agents for the Application of Normal-Strength, High-Fluidity Concrete

High fluidity concrete exhibits an excellent self-compacting property. However, the application of typical high-fluidity concrete is limited in the normal strength range (18~35 MPa) due to the large amount of binder. Therefore, it is important to solve these problems by adding a viscosity modifying agent (VMA) with a superplasticizer (PCE), which helps to improve the fluidity of the concrete. In addition, the rheology and stability of the concrete with VMA can be improved by preventing bleeding and segregation issues. Current studies focused on the physical phenomena of concrete such as the fluidity, rheological properties, and compressive strength of normal-strength, high-fluidity concrete (NSHFC) with different types of a polycarboxylate-based superplasticizer (NPCE). The obtained results suggested that the combinations of all-in-one polycarboxylate-based superplasticizers (NPCE) did not cause any cohesion or sedimentation even stored for a long time. The combination of three types of VMA showed the best fluidity (initial slump flow of 595~630 mm) without any segregation and bleeding, and the compressive strength at 28 days was also found to be the highest: 34–37 MPa. From these results, the combination of PCE (2.0%) + HPMC (0.3%) + WG (0.1%) + ST (0.1%) showed an 18% higher plastic viscosity and -4.4% lower yield stress than Plain.

A Sheathed Spike Gene, TaWUS-like Inhibits Stem Elongation in Common Wheat by Regulating Hormone Levels

Background: The elongation and development of wheat (Triticum aestivum L.) stem play an important role in plant architecture. Shortened stem would result in sheathed spike and low yield in crops. To elucidate the molecular mechanisms underlying sheathed spike would be helpful for plant architecture and yield. Results: We found a novel gene, TaWUS-like（WUSCHEL-related homeobox like）, which regulated sheathed spike and plant architecture in wheat. The plant height of overexpression transgenic lines were significantly decreased and the spike was not completely elongated and enclosed in flag leaf sheaths. Besides, the increase of tiller angle resulted in loose plant architecture and lower yield. The statistical and cytological analysis demonstrated that the length of the uppermost and secondary internode was significantly shortened, especially the uppermost internode was only half length of wild-type. The parenchyma cells obviously reduced and elongated insufficiently. The analysis of hormone content showed that there was a lack of GA3 in internodes but a higher BR content. Conclusions: TaWUS-like may inhibit the synthesis of GA and/or BR and affect the function of signal transduction of these hormones, which further caused stem shortening and plant dwarfing in wheat.

Prevalence and Incidence of Cassava (Manihot esculenta) Brown Leaf Spot Disease Caused by Cercospora heningsii in Macuata Province, Vanua Levu, Fiji

Cassava (Manihot esculenta Crantz) is a crop of many values in the tropical and subtropical regions of the globe. In Fiji, cassava is cultivated on vast acres of land but, the yield obtained is relatively lower because of many constraints, including the prevalence of diseases caused by the different pathogens. Among various pathogens responsible for a lower yield, the cassava brown leaf spot disease caused by Cercospora heningsii is responsible for causing enormous annual losses of cassava in tropical and subtropical regions. Because there is very little information regarding the association of the brown leaf spot disease and cassava in the country, the present study using survey as research instrument endeavors to determine the disease incidence and prevalence of brown leaf spot disease in the cassava fields of three villages (Mani Road, Boca, and Anuve) in the Bulileka area of the Macauta province in Vanua Levu, Fiji. The study found that brown leaf spot disease prevailed (100%) in all three villages. The percentage of disease incidence ranged from 36.4% to 42.9%. The maximum incidence (42.9%) of cassava brown leaf spot disease was found in Anuve village, followed by Mani Road village (38.2%), with the lowest disease incidence recorded for Boca village (36.4%).

Development of Low-Yield Stress Co–Cr–W–Ni Alloy by Adding 6 Mass Pct Mn for Balloon-Expandable Stents

This is the first report presenting the development of a Co–Cr–W–Ni–Mn alloy by adding 6 mass pct Mn to ASTM F90 Co–20Cr–15W–10Ni (CCWN, mass pct) alloy for use as balloon-expandable stents with an excellent balance of mechanical properties and corrosion resistance. The effects of Mn addition on the microstructures as well as the mechanical and corrosion properties were investigated after hot forging, solution treatment, swaging, and static recrystallization. The Mn-added alloy with a grain size of ~ 20 µm (recrystallization condition: 1523 K, 150 seconds) exhibited an ultimate tensile strength of 1131 MPa, 0.2 pct proof stress of 535 MPa, and plastic elongation of 66 pct. Additionally, it exhibited higher ductility and lower yield stress while maintaining high strength compared to the ASTM F90 CCWN alloy. The formation of intersecting stacking faults was suppressed by increasing the stacking fault energy (SFE) with Mn addition, resulting in a lower yield stress. The low-yield stress is effective in suppressing stent recoil. In addition, strain-induced martensitic transformation during plastic deformation was suppressed by increasing the SFE, thereby improving the ductility. The Mn-added alloys also exhibited good corrosion resistance, similar to the ASTM F90 CCWN alloy. Mn-added Co–Cr–W–Ni alloys are suitable for use as balloon-expandable stents.

Influence of Sowing Dates and Varieties on the Biological Yield of Wheat Crop (Triticum aestivum L.)

A field experiment was carried out in Dar-ul-Aman Research Farm, Kabul Afghanistan in 2017, to study the influence of sowing dates and varieties on the biological yield of wheat crop (Triticum aestivum L.). The experiment was laid out in RCBD with a split-plot arrangement having three replications. Wheat was sown in different sowing dates i.e., October 24th, November 2nd, 12th, and 22nd in main plots, whereas five wheat varieties (Chounth # 1-2010, Moqawim-09, Shisham Bagh-08, Dar-ul-Aman-07 and Solh 2002) were in sub plots. November 2nd planted wheat had a highest biological yield of (6642.1 kg ha-1) followed by October 24th and November 12th which gave (6576.5) and (5711.0 kg ha-1) respectively. The lowest biological yield of (2975.1 kg ha-1) was given by the wheat varieties sown on November 22nd. Among the all-wheat varieties, Solh 2002, had significantly higher biological yield of (6263.7 kg ha-1) followed by Shisham Bagh-08 with biological yield of (5571.8 kg ha-1). However, Moqawim-09 had lowest biological yield of (4976.8 kg ha-1) compare to other varieties. While, evaluating performance of different wheat varieties on different sowing dates, Solh 2002, resulted in maximum biological yield (7476.2 kg ha-1) on November 2nd followed by Dar-ul-Aman-07 (6933.3 kg ha-1) and Shisham Bagh-08 (6860.0 kg ha-1) on November 2nd and October 24th respectively. On the other hand, Dar-ul-Aman-07 had lowest biological yield among the varieties (2015.5 kg ha-1) on November 22nd, it shows that, Dar-ul-Aman-07 had highest biological yield on early planting but lower yield on late sowing dates. The study shows that delay in wheat planting or selection of other varieties rather than Solh 2002 and Dar-ul-Aman-07 reduces the biological yield of the crop.