Yield Potential Research Articles

Global needs for nitrogen fertilizer to improve wheat yield under climate change.

Increasing global food demand will require more food production1 without further exceeding the planetary boundaries2 while simultaneously adapting to climate change3. We used an ensemble of wheat simulation models with improved sink and source traits from the highest-yielding wheat genotypes4 to quantify potential yield gains and associated nitrogen requirements. This was explored for current and climate change scenarios across representative sites of major world wheat producing regions. The improved sink and source traits increased yield by 16% with current nitrogen fertilizer applications under both current climate and mid-century climate change scenarios. To achieve the full yield potential-a 52% increase in global average yield under a mid-century high warming climate scenario (RCP8.5), fertilizer use would need to increase fourfold over current use, which would unavoidably lead to higher environmental impacts from wheat production. Our results show the need to improve soil nitrogen availability and nitrogen use efficiency, along with yield potential.

Yield, milling quality, rice quality and preferences of superior and specific location rice varieties

Abstract Grain and rice characteristics are a description of the post-harvest quality of rice which is a consideration for farmers, traders, and consumers in choosing rice to be developed and consumed. This study aims to determine the yield, milling quality, rice quality and preference of 5 rice varieties in Indonesia, they were Inpari 32 HDB, Inpari 42 Agritan GSR, Inpari 45 Dirgahayu, Pamelen and Inpari IR Nutri Zinc. The study used a non-factorial Randomized Group Design, rice varieties as treatments, 5 replications. Rice was harvested using 2 methods, namely sickle (manual harvesting) and combine harvester. Determination of Milling Quality, rough rice was milled using a mini electric grain whitener LTJM-2008 then measured the percentage of hulled rice, unhulled rice, bran, and husk. Determination of rice quality, 25 grams of rice samples were sorted manually and measured the percentage of head rice, broken, groats and damaged then determined the grade of rice based on SNI 6128: 2015. The results showed that the rice yield manually and using a combine harvester was different from the potential yield. The milling quality and rice quality of each variety were significantly different (p=0.05%). Rice quality classification based on SNI 6128:2015 shows that Inpari 42 Agritan GSR and Inpari IR Nutri Zinc was included in Medium I, pamelen and Inpari 32 HDB were included in Medium II, and Inpari 45 Dirgahayu was under Medium III. Inpari 32 HDB was the rice variety with the highest preference.

Susceptibility of corn hybrids to corn stunt complex transmitted by the corn leafhopper, Dalbulus maidis (DeLong & Wolcott, 1923) in Brazil

Corn (Zea mays L.) production plays a key role in the global agricultural scenario. Corn is currently the most produced cereal in the world, with more than 1.1 billion tons harvested in 2021. The main pest that affects corn in Latin America is the corn leafhopper (Dalbulus maidis) (DeLong & Wolcott, 1923). This insect causes direct damage to Zea mays plants through suction of the corn sap, but its importance is greater due to the transmission of two phytopathogens of the mollicute class: the phytoplasma (MBSP – maize bushy stunt phytoplasma) that causes the red stunting; and spiroplasma (Spiroplasma kunkelii) which causes pale stunting; in addition to a virus, the corn stripe virus (MRFV – maize rayado fino virus). Stunting is a systemic disease that affects the physiology, nutrition, and development of the corn crop, significantly reducing its productivity. Therefore, the use of resistant hybrids is the main alternative to reduce the incidence and damage caused by corn stunting. This work aimed to evaluate the susceptibility of maize hybrids to the stunting complex transmitted by the corn leafhopper in three different sowing dates. The experiment was carried out with 63 corn hybrids in three different sowing times, the first being on 11/24/2022, the second on 12/30/2022 and the third on 02/06/2023. The hybrids SHSuper CONV, NTX454 VT PRO2 and FS670 PWU were the ones that had the lowest rates of stunting severity, showing a high resistance to this disease complex. The hybrids AG9025 PRO3, DKB240 PRO3 and K9300 PRO3 were the ones that presented the highest disease severity scores (6 to 5.7 on the scale used), indicating a high susceptibility to the stunt pathogens complex. The use of less susceptible hybrids is one of the main components for managing stunting diseases complex in the corn crop in South America, being one of the most important features, together with potential yield, as a parameter for growers to select the hybrid to be used.

Biochar as a carbon dioxide removal strategy in integrated long-run mitigation scenarios

Limiting global warming to under 2 °C would require stringent mitigation and likely additional carbon dioxide removal (CDR) to compensate for otherwise unabated emissions. Because of its technology readiness, relatively low cost, and potential co-benefits, the application of biochar to soils could be an effective CDR strategy. We use the Global Change Analysis Model, a global multisector model, to analyze biochar deployment in the context of energy system uses of biomass with CDR under different carbon price trajectories. We find that biochar can create an annual sink of up to 2.8 GtCO2 per year, reducing global mean temperature increases by an additional 0.5%–1.8% across scenarios by 2100 for a given carbon price path. In our scenarios, biochar’s deployment is dependent on potential crop yield gains and application rates, and the competition for resources with other CDR measures. We find that biochar can serve as a competitive CDR strategy, especially at lower carbon prices when bioenergy with carbon capture and storage is not yet economical.

Improvement of superior soybean variety, Biosoy-1 for aluminium tolerance character

Abstract Indonesia has lot of sub-optimal land, especially outside Java, but generally the land is acidic, contains lots of heavy metals and is poor in nutrients, making it less suitable for agriculture, including soybean cultivation. Efforts to improve land conditions through the application of liming are quite helpful, but are inefficient because they are easily washed out by rainwater and require expensive labor and costs for large areas. The use of tolerant and adaptive varieties for acidic land are effective solutions. Biosoy-1 and Biosoy-2 are new superior soybean varieties released by Ministry of Agriculture which have high yield potential (more than 3 tons/ha) and big grain, but are less adaptive to sub-optimal land so that the planting area is still limited. Efforts to improve the Biosoy variety for aluminum stress tolerant have been carried out through the introgression of the MaMt2 gene from transgenic soybean lines into the Biosoy variety. Thirty of F1 soybean seeds have been produced and 24 plants of them were positive for carrying the MaMt2 gene. Furthermore, the F1-MaMt2 plants were backcrossed to Biosoy several times in order to obtain a soybean line with high yield and tolerance to aluminum stress. Currently, a total of 16 number of BC3F1 seeds are being planting in confined screen house for molecular analysis and following by backcrossing to Biosoy-1 variety to produce BC4F1 seeds.

Influence of higher levels of NPK fertilizers on growth, yield, and profitability of three potato varieties in Surma, Bajhang, Nepal

Potato is a crucial food and cash crop with high yield potential in many parts of the Bajhang district. However, achieving optimal yields can be hindered by inconsistent NPK fertilizer application rates and suboptimal potato variety selection, including instances where no fertilizers are used at all by the farmers. To address these challenges and determine the most effective NPK fertilizer rates and potato varieties, a field experiment was conducted in Surma rural municipality of Bajhang district. The experiment utilized a randomized complete block design (RCBD) with three replications, to evaluate the effects of four NPK fertilizer rates (0:0:0, 50:50:50, 100:100:60, and 150:150:90 kg NPK/ha) and three potato varieties (Khumal Seto, Cardinal, and Bajhang Local), on growth, yield, and economic profitability. Statistical analysis, including analysis of variance and Duncan's multiple range test (DMRT), indicated that the highest values for plant height, canopy diameter, number of leaves, number of main stems, tuber weight, fresh weight of leaves and stems, average tuber diameter and number of marketable tubers per hill were consistently observed higher in either the Khumal Seto or Bajhang Local potato varieties. Similarly, these results were particularly prominent with the application of 150:150:90 kg NPK/ha. Economic analysis demonstrated that the Khumal Seto variety showed superior performance in terms of gross benefit, net benefit, and benefit-to-cost ratio (NPR 1,805,714.29, NPR 1,306,168.83, and 3.61, respectively) when compared to other varieties. Similarly, the application of 150:150:90 kg NPK/ha resulted in higher economic returns (NPR 1,645,714.29, NPR 1,129,908.83, and 3.19). In conclusion, using higher levels of mineral fertilizers (150:150:90 kg NPK/ha) with high yielding and well adapted potato varieties such as Khumal Seto and Bajhang Local significantly enhances growth, yield, and profitability in potato cultivation, as demonstrated by the findings of this study.

A 7×7 diallel cross for developing high-yielding and saline-tolerant barley (Hordeum vulgare L.)

In this experiment, F1s produced from a 7 × 7 half-diallel cross along with their parents were evaluated to develop high yielding and saline-tolerant barley lines. The investigation focused on the general combining ability (GCA) of parents, specific combining ability (SCA) of offspring, genetic action, and heterosis of eight quantitative variables. Genetic analysis and potence ratio suggested that different degrees of dominance controlling the inheritance of the studied traits. Significant GCA and SCA variances suggested the presence of both additive and non-additive gene actions controlling the traits. However, a GCA:SCA ratio lower than 1 indicated the preponderance of the non-additive gene action involved in the expression of the traits. The parents P5 and P6 possess the genetic potential favorable for early and short stature in their F1s. Conversely, P2 and P4 were more likely to produce short F1s with high yield potential. Based on the mean performance, SCA, and heterobeltiosis, crosses P2 × P3, P2 × P7, P3 × P4, P4 × P5, P5 × P6, and P6 × P7 were selected as promising F1s for earliness, short stature, and high yield potential. These crosses are recommended for further breeding to obtain early-maturing and high-yielding segregants. To identify saline-tolerant F1s, screening was conducted in saline media prepared in half-strength Hoagland solution. The salinity stress involved exposing F1s to 100 mM NaCl for first 10 days, and followed by an increase to 150 mM until maturity. Among the F1s, five crosses (P1 × P2, P2 × P3, P3 × P5, P4 × P6, and P4 × P7) exhibited promising signs of saline tolerance based on a comprehensive evaluation of healthy seed set, K+/Na+ ratio, root volume, generation of reactive oxygen species (O2•− and H2O2), and activities of key antioxidant enzymes like superoxide dismutase (SOD), catalase (CAT), peroxidase (POD), ascorbate peroxidase (APX), and glutathione reductase (GR). These crosses will undergo further evaluation in the next filial generation to confirm heritable saline tolerance.

The distribution of rainfall in areas suitable for sugarcane farming in Blitar Regency, East Java

Abstract Expansion of sugarcane in East Java continue to be implemented in addition to intensification to increase sugarcane production in East Java, including expansion to Blitar Regency. This study aims to determine the rainfall distribution in areas suitable for sugarcane cultivation in Blitar Regency, East Java. This study was done in 2022 by combining a sugarcane land suitability map in Blitar Regency from the Indonesian Center for Agricultural Land Resources Research and Development and an annual isohyet map. Maps showing the rainfall distribution that the further north in Blitar the more elevation and rainfall and decreasing to the south. Annual rainfall distribution of 1500-2000 mm and 2000-2500 mm in the areas of moderately and marginally suitable for sugarcane covered total area of 25,918.59 ha and 22,689.90 ha or 15.83% and 13.86% of the total existing land area, respectively. When expanding sugarcane development, it is essential to consider the rainfall distribution along with the spatial distribution of land. Therefore, field trials are needed in each zoning to determine the productivity level of sugarcane and sugar. Complementing the spatial distribution of land for sugarcane with the rainfall distribution in each zone is important to identify yield potential for each suitability class.

Would reducing chlorophyll content result in a higher photosynthesis nitrogen use efficiency in crops?

AbstractDecreasing antenna size is considered a potential option for improving photosynthesis and increasing yield potential. Reducing chlorophyll content has been employed as a strategy to decrease antenna size. One of the commonly mentioned advantages of this approach is its ability to enhance crop nitrogen use efficiency (NUE); however, there is limited field evidence supporting this claim. In this study, we utilized a rice mutant called p35s‐Ami‐YGL1, which exhibits lower chlorophyll content and smaller antenna size, to investigate the effects of modifying leaf chlorophyll content on tissue nitrogen content and NUE. Our results demonstrate that the nitrogen contents in various tissues, including seed tissue, increased on a weight basis in p35s‐Ami‐YGL1 mutants while exhibiting a decrease in C:N ratio. Simultaneously, we observed a reduction in tissue carbon content along with an increase in the levels of chlorophyll precursors such as Proto IX. Specifically, we observed an upregulation in the expression of genes associated with photosynthetic light reactions and chlorophyll metabolism, while there was no increase in the expression of genes involved in the CBB cycle and nitrogen metabolism. In addition, p35s‐Ami‐YGL1 experienced increased photodamage. These findings suggest that the alterations in the C:N ratio and nitrogen content in plants may be attributed to Proto IX‐mediated photodamage and chloroplast reverse transduction signaling. Besides, these results suggest that the observed increase in tissue nitrogen content in p35s‐Ami‐YGL1 does not reflect an increase in plant nitrogen absorption or use efficiency, rather it is a result of stunted carbon fixation capacity.

Adaptation test of rainfed rice fields highland in Jambi Indonesia

Abstract Increasing national rice productivity can be achieved by optimizing existing resources, including rainfed rice fields in highlands areas. Rainfed rice fields in Indonesia are quite diverse in agroecosystem conditions, ranging from lowlands to highlands. Indonesia has the potential for highlands that can be planted with rice to support national rice production. The high variety of biophysical, edaphic, and biotic conditions of the main agroecological areas of rice cultivation makes it difficult to obtain varieties that can grow well in all types of agroecosystems. The purpose of this study is to determine the potential yield and adaptability of rice hope strains to anaerobic germination conditions in rainfed land and highland rainfed rice strains. Ten rice strains and two reference varieties from The Indonesian Centre for Rice Research Sukamandi in West Java were tested in 2021, with four repetitions. The area of each plot of 4 x 5 m was carried out on rainfed rice fields in Kerinci regency with an altitude of 788.5 meters above sea level and a Sungai Penuh regency of 795 meters above sea level. Observations were made of vegetative, generative parameters of plants, as well as temperature and humidity. Results showed that the strains with the highest production and medium harvest age had good observational agronomic parameters, namely in strains B15617E-4-MR-3, BP29337-2-CRB-0-SKI-0-7-PWK-1-SKI-3-3, and BP19980-JK-2-IND-2-SKI-0-PWK-1-SKI-5-1.

GENETIC DIVERSITY ANALYSIS IN SOME LOW LAND RICE LANDRACES USING AGRO-MORPHOLOGICAL TRAITS

Forty four landraces of lowland rice were assessed for genetic diversity using D2 statistics based on various grain yielding parameters. Significant variability was found among the traits studied. Eight diverse clusters were made to set them into groups. The pattern of distribution of genotypes from different eco geographic regions into various clusters was at random indicating that geographical diversity and genetic diversity were not related. The maximum inter-cluster distance was observed between cluster III and IV (1033.15), followed by clusters II and VIII (935.07). Maximum intra-cluster distance was observed in cluster IV (731.01). Divergence analysis revealed significant variation among the parental lines for all the agro-morphological traits. Cluster analysis showed that superior cultivars like ‘Kanakchur’ from cluster IV; cv. ‘FR13A’, ‘Jaladhi2’, ‘Matla’ and ‘Purni’ from cluster III; cv. ‘Latisail’, ‘Pimpu Dibasa’, ‘Jeeringa Samba’ and ‘Shib Chato’ from cluster II; and cv. ‘ARC11210’, ‘Kumar Gore’, ‘NC678’, ‘Sada Mota’ and ‘Kantaranga’ from cluster VI may be taken in hybridization program, based on the genetic distance, relative contribution of characters towards total divergence and yield potential of genotypes. The characters viz., days to 50% flowering, plant height, panicle weight and number of grains panicle-1contributed maximum towards the divergence among genotypes taken for this study. So, allelic diversity among the genotypes and the concerned traits taken for this experiment should be taken into consideration while framing a rice breeding programme.

Seed Longevity of Soybean (Glycine max L.) Cultivars Under Lightless Storage

Soybean seeds in tropical countries are prone to rapid deterioration due to environmental condition during storage, leading to a decrease in seed quality and ultimately resulting in low potential yield. Longevity of seed during storage is influenced by genetic and environmental factors such as light. Therefore, this study aimed to determine the effect of light on the vigour of two soybean seeds cultivars (Demas 1 & Devon 1 cvs) stored for three months. The investigation was conducted from February to May 2022 at Seed Technology Laboratory, Faculty of Agriculture, Universitas Padjadjaran. A correlational method was employed to assess the relationship between seed quality of Demas 1 and Devon 1 in light and lightless storage. Furthermore, data were analyzed using correlation regression and t-test to compare the two populations. The results showed that there was a high correlation between the physical and physiological quality of seeds. There were also differences in seed response to light, and this was observed from the moisture content, weight of 100 seeds, germination rate, and simultaneous growth percentage traits. Considering the seed quality traits, Demas 1 had the best vigour value after storage in dark conditions. It is worth noting that both cultivars exhibited signs of deterioration during storage. However, the rate of deterioration was slowed down due to lightless condition.

Soybean planting dates and maturity groups: Maximizing yield potential and decreasing risk in Louisiana

AbstractSoybean [Glycine max (L.) Merr.] producers in Louisiana began shifting to an early soybean production system (ESPS) in the early 2000s by planting earlier maturing varieties in April and May. Although this shift in planting practices has been supported by research elsewhere beginning in the mid‐1990s, there is minimum data focusing on the ESPS across Louisiana. The overall objective of this research was to evaluate the effect of planting date, maturity group (MG), and their combination across a comprehensive set of yield environments in the state of Louisiana to determine the combination of optimum planting date and MG for soybean production. We gathered field data from the 2013 to 2020 seasons originated from three Louisiana State University AgCenter research stations and four seed companies. A total of 428, 926, and 331 observations were analyzed from the Northeast, Central, and Southwest Louisiana regions, respectively. When including all data from across Louisiana, the optimum planting date was April 30. Breaking by regions, the average optimum planting date for the Northeast Louisiana region was April 9. The Central and Southwest results were divided by MG section, and the approximate optimum planting dates were April 15 and May 15, respectively. These results support the ESPS for the Northeast and Central Louisiana regions, but not for the Southwest Louisiana region. Optimizing planting recommendation is a critical component for supporting the development of varieties suitable for the southern production systems of the United States.

Optimal Plant Density Is Key for Maximizing Maize Yield in Calcareous Soil of the South Pannonian Basin.

Plant density, the number of plants per unit area, is an important factor in maize production. Plant density exhibits high variability and depends on a number of factors, i.e., the length of the growing period of the hybrid, the morphological characteristics of the plant, the amount and distribution of precipitation during the growing season, the reserve of winter moisture in the soil, the level of soil fertility, the time of sowing, agronomic management practices, and biomass and yield. The objective of this paper was to determine the agronomic optimal plant density for maize in calcareous soil in the semiarid conditions of the South Pannonian Basin. Field experiments were conducted at the experimental field-IFVCNS (two locations: Rimski Šančevi and Srbobran) to evaluate four plant densities (55,000; 65,000; 75,000; and 85,000 plants ha-1). The experimental sites "Rimski Šančevi" and "Srbobran" are located in the typical chernozem zone of the southern part of the Pannonian Basin. On average for all hybrids, the grain yield followed a second-degree polynomial model in response to the increasing planting density, with the highest value at plant density (PD2: 65,000 plants ha-1). To achieve maximum yield, the optimal planting density for corn hybrids of the FAO 200 group should be 57,600 plants ha-1, for the FAO 300 group 64,300 plants ha-1, for the FAO 400 group 68,700 plants ha-1, for the FAO 500 group 66,800 plants ha-1, and for the FAO 600 group 63,500 plants ha-1. "Which-Won-Where" biplot showed that the hybrid H24 from FAO 600 group was the highest yielding in all of the environments. Hybrid H17 from the same FAO group was the most stable across all of the environments. Selected hybrids may further be studied for planting density and nutritional requirements for getting maximum yield. By introducing new maize hybrids with higher genetic yield potential and better agronomic management practices, modern mechanization and agricultural techniques allowed to increase planting densities.

Deep tillage combined with straw biochar return increases rice yield by improving nitrogen availability and root distribution in the subsoil

ContextAfter over 20 years of practicing shallow rotary tillage combined with straw direct return in the middle and lower Yangtze regions of China, the yield potential has gradually disappeared, and new alternative tillage practices are required to continuously increase rice yield. ObjectiveThis paper investigates the yield effect and mechanism of deep tillage combined with straw return through two consecutive years of a field experiment. MethodsThree tillage depths (shallow tillage 6–7 cm, ST; medium tillage 12–14 cm, MT; and deep tillage 25–28 cm, DT) plus three straw management methods (no straw return, NR; straw direct return, SR; and straw biochar return based on the same amount of carbon input as SR, BR) were set up as experiment treatments. The aboveground and belowground growth traits of rice and soil nitrogen (N) status were determined. ResultsCompared with ST and MT, the DT enlarged rice root distribution and increased soil N content in the middle and lower soil layers (7–28 cm) and decreased the root–shoot ratio at the flowering stage, which was conducive to absorbing more soil nutrients from the subsoil and allocating more photosynthetic products to the aboveground parts and grain. The MT and DT increased spike number and rice yield compared with ST. Compared with NR, both SR and BR increased soil total and available N contents, and the remaining soil available N content at the harvest stage of BR was lower than that of SR. Straw return (SR and BR) improved rice yield by increasing spike number and kernels per spike, and the effect of BR on increasing rice yield was greater than that of SR. ConclusionsThe DT combined with BR increased root distribution and N content in the subsoil, promoted the utilization of subsoil's nutrients, and increased rice yield. It is therefore a promising tillage practice for achieving high rice yields.

Harnessing rooftop solar photovoltaic potential in Islamabad, Pakistan: A remote sensing and deep learning approach

Solar energy shines as a beacon for sustainable development, with rooftop solar photovoltaic (PV) installations playing a crucial role. This study proposes a novel framework to precisely assess citywide existing solar power generation and analyze future potential under various rooftop utilization scenarios (10–50 %). To illustrate the methodology, the existing solar PV yield and future potential of Islamabad are explored as a case study. Employing open-source satellite data and deep learning (DL), this study quantified the electricity generation from current solar infrastructure and projected future possibilities. DL models like Mask R–CNN and Deeplab-v3 are trained on extensive custom datasets for solar panels and rooftops extraction. The study delineated 19,000 solar arrays, covering an area of 0.8 sqkm, and extracted 75.08 sqkm of suitable rooftops for future installations. The analysis revealed, current solar infrastructure generates 141.42 GWh electricity, satisfying 6.34 % of Islamabad's annual energy demand. Utilizing 50 % rooftop area could generate 6578 GWh annually, meeting 294 % of the city's electricity needs. This research contributes to the strategic planning for solar energy infrastructure, demonstrating the substantial role rooftop solar can play in meeting urban energy needs. This can inform policy decisions and guide investment opportunities for expanding clean energy in the city.

Proximal canopy sensing of twenty-two bread wheat genotypes for nutritional quality, yield attributes and grain yield under Mediterranean climate

To ensure nutritional security of rapidly increasing population, research interest has revitalized in determining the nutritional quality traits of staple food crops, especially wheat. Besides higher yield potential, research gaps exist regarding nutritional quality assessment of promising wheat genotypes grown under the Mediterranean climate. A field study was conducted to determine the relationship between yield components and quality characteristics of 22 bread wheat genotypes using the SPAD meter, GreenSeeker (NDVI), and CM-1000 chlorophyll meter at different growing stages (Stem elongation, Heading, Anthesis and Milk stage). The recorded findings revealed that G-41 genotype surpassed the rest of bread wheat genotypes by recording the maximum grain yield, whereas G-60 genotype exhibited the highest protein and wet gluten content. Among response variables, SPAD and NDVI values at the heading stage and CM-1000 values at the milk stage were found to be statistically insignificant. According to the correlation and biplot analysis, a significant positive correlation was found between the SPAD values measured for the stem elongation, anthesis and milk stage and yield and quality characteristics. Significant positive correlations were found between the NDVI values at the stem elongation, anthesis, and milk stages and the yield components, and between the CM-1000 value at the heading stage and the grain yield.

Numerical investigation of diesel spray combustion characteristics in the ammonia/air atmosphere

Ammonia/diesel dual-fuel combustion mode is a promising strategy for decarbonizing internal combustion engines. However, the impact of a premixed ammonia/air atmosphere on diesel spray combustion characteristics is not fully understood. This study analyzes the effects of premixed ammonia/air atmosphere, including premixed equivalence ratio, the cooling effect of liquid ammonia vaporization, and ambient oxygen concentration on the ignition and combustion characteristics and soot yield potential of diesel spray. Numerical simulations using n-heptane as a single-component diesel surrogate reveal that increasing the premixed ammonia equivalence ratio and lowering ambient oxygen concentration extend the ignition delay times and flame lift-off length of n-heptane spray. Liquid ammonia vaporization further prolongs the ignition delay by lowering the ambient temperature during n-heptane auto-ignition. Moreover, there is a trade-off between ignition delay and soot yield potential as longer ignition delays allow more thorough mixing of diesel and premixed gas, reducing soot formation. Given the substantial extension of ignition delay in ammonia/air atmospheres, it is recommended that ammonia/diesel dual-fuel engines operate with higher charged gas temperatures to ensure stable and repeatable ignition events. The negative effects of increased soot yield could be mitigated by using ammonia to reduce soot precursors. Overall, these results underline the need for further fundamental studies on ammonia/diesel co-combustion to facilitate the commercial adoption of ammonia/diesel dual-fuel engines.

Optimal Nitrogen Fertilizer Rates for Soybean Cultivation

The soybean (Glycine max. L. Merr) can satisfy a large portion of its requirement for nitrogen (N) by living in symbiosis with symbiotic bacteria. However, this source of N may be inadequate in varieties with high yield potential. To fully exploit this potential, soybeans should additionally utilize mineral forms of nitrogen present in the soil. The aim of this study was to determine the effect of varied nitrogen fertilizer application rates on the dry weight of the separated parts of soybean plants and the whole plant, including the number and weight of root nodules, the potential to reduce atmospheric nitrogen (N2), and the content and uptake of nitrogen. Four levels of pre-sowing nitrogen fertilizer supply were tested: 0, 60, 120, and 180 kg N·ha−1. Measurements of the tested parameters were taken during the flowering stage and the fully ripe stage. During the flowering stage, a reduction in the number of root nodules was observed following the application of 120 and 180 kg N·ha−1. In the fully ripe stage, each increase in nitrogen application caused a systematic decrease in the number of nodules on the roots. Increasing the level of nitrogen application therefore reduced the N2 fixation potential of soybeans, regardless of the developmental stage. The use of high doses of nitrogen in soybean cultivation did not increase seed yield or the weight of the entire plant. With high doses of nitrogen, the content and accumulation of nitrogen in soybean seeds and total mass did not increase. Therefore, the content and yield of crude protein did not increase. The main organ of nitrogen accumulation in the soybean flowering stage was the leaves (58.6–64.8% of total N uptake), however, in the fully ripe stage, it was the seeds (66.8–74.2% of total N uptake).

Effects of drought on morpho-physiological attributes and secondary metabolites of wheat genotypes: Growth traits, seed yield and stress tolerance indices

In parallel with rapid growth in human population, increasing deficiency of water for irrigation along with abruptly changing environmental conditions has increased the food insecurity problem which needs immediate attention to secure the future food security. This study aimed to identify the water stress tolerance and high yielding potential of newly developed wheat genotypes, based on agronomic, morphological and biochemical aspects, along with the stress tolerance indices (STI). These genotypes were developed through conventional breeding from a cross (Bhakkar x S-24) and named as BS following the names of the parental genotypes. The experiment comprised a total 20 newly developed genotypes and 2 parental genotypes. Split plot field experiment was conducted using reduced number of irrigations as water stress treatment. All studied genotypes exhibited distinct negative impacts of deficit irrigation with respect to various studied agronomic attributes but was genotype specific. There were genotype-specific variations to deficit irrigation, regarding leaf chlorophyll contents, water relations, membrane lipid peroxidation, as well as antioxidative defense mechanism. Under deficit irrigation genotypes BS3, BS4, BS8, BS9, and BS20 demonstrated superiority in growth and grain yield related attributes that was attributed to their effective performance in maintaining better water content through better osmotic adjustment, chlorophyll levels, as well as better defense against oxidative stress. Comparatively less reductions in growth and yield i.e 26.43 % and 30.56 %, 28.94 % and 28.01 %, 32.13 % and 30.07 %, 34.35 % and 31.36 %, and 24.14 % and 26.55 % were recorded in BS3, BS4, BS8, BS9, and BS20 respectively as compared with remaining genotypes. However, the opposite was true for genotypes BS7, BS13, BS15 followed by BS6 and BS7. Stress tolerance indices also showed the better tolerance of the genotype BS3, BS4, BS8, BS9 and BS20. In conclusion, breeding programs for the development of stress-tolerant wheat genotypes should also consider the physio-biochemical mechanisms alongside the agronomic traits. This holistic approach will contribute significantly for the selection of genotypes that exhibit resilience to water deficit stress with high yield potential.