Full Yield Research Articles

Sources and splitting of special fertilizers application in coffee crop

This study assesses special and mineral fertilizers and the splitting of fertilizer application in coffee - a crop with high nutritional requirements for full yield potential. A 4 × 3 factorial scheme was implemented with four fertilizers [mineral, mineral with polymer, organomineral with cellulosic residue (OM-CR), or sugarcane filter cake (OM-FC)] and three application times, or splits (100% at once, 50%+50%, 33.3%+33.3%+33.3%). Coffee plant height, canopy diameter, plagiotropic branch growth, leaf chlorophyll, nutrient contents in the soil and leaves, and harvest yield after fruit maturation were evaluated in two consecutive crop cycles. The results indicated that organomineral fertilizers performed similarly to other fertilizers regarding coffee leaf chlorophyll and plant height. Only one fertilizer application effectively increased canopy diameter in both crop cycles. In the first crop cycle, OM-FC and conventional mineral fertilizers were significantly better for coffee foliar N content. In contrast, in the second crop cycle, mineral-P, OM-CR, and OM-FC achieved satisfactory results with one fertilizer application, whereas conventional mineral fertilizer required three applications for superior results. There are no differences in leaf P content among different sources and frequencies of application. Still, mineral-P and OM-CR had better soil P content than the conventional mineral fertilizer. OM-CR required two applications to reach high levels of leaf K content, while other fertilizers achieved it with one application. Organomineral and protected mineral fertilizers performed similarly in both crop cycles, with two applications resulting in greater coffee yield in the second cycle, regardless of the fertilizer used.

Polyvinyl chloride microplastics and drought co-exposure alter rice growth by affecting metabolomics and proteomics

Microplastics, interacting with drought stress, have become threat to crops by altering soil environment. Currently, the effect of combined microplastic and drought stress on crop growth remain poorly understood. In this work, the mechanism of multi-stress responses was investigated under the exposure of polvinylchloride microplastic (PV) and drought (D) individually and in combination (DPV) on rice varieties Hanyou73 and Q280 through proteomics and metabolomic analysis. All treatments negatively affect chlorophyll content, antioxidant enzyme activities, rice grain composition, metabolome and proteomic profiling of both rice varieties. Full rice grain yield was decreased under all treatments except PV treatment in which it was increased in both rice varieties. DPV treatment shows the lowest grain yield and more adverse effects on metabolome by affecting glycerophospholipid metabolism, tryptophan metabolism and alanine, aspartate and glutamate metabolism. Soluble sugar contents were decreased in H73 but in Q280 increased by 159 % under DPV and 123 % in PV treatment, compared to their control group. The results from metabolomics illustrate that glycerophospholipid metabolism is commonly altered in both rice types under all treatments. PV and drought alone and in combination induce extensive alterations in proteomics of rice leaves especially impacting proteins related to binding, translation and photosynthetic process. The results reveal that PV and DPV treatments highly distort the abundance of metabolites and proteins in both rice types, demonstrating that microplastic toxicity effects on rice plants become more severe when combined with drought stress.

Strength and leaching behavior of CaO- and MgO-treated Cd-contaminated soils subjected to partial and full carbonation

Cadmium (Cd)-contaminated soils may pose a significant threat on human health. They are often treated with quick lime (CaO) and reactive magnesia (MgO), but these treatments often result in low strength. Hence, in this study, partial and full carbonation are used to enhance the stabilization/solidification of CaO- and MgO-treated Cd-contaminated soils, aiming to achieve CO2 sequestration, strength improvement, and Cd immobilization. Performance of treated contaminated soils is evaluated through unconfined compressive strength (UCS), leaching, X-ray diffraction (XRD), and thermogravimetric analysis (TGA) tests. The results indicate that carbonation significantly enhances the UCS of both CaO- and MgO-treated Cd-contaminated soils. After carbonation, MgO-treated soils exhibit higher UCS than CaO-treated soils. Partial and full carbonation yield similar UCS in CaO-treated soils, while full carbonation results in higher UCS in MgO-treated soils. For CaO-treated soils, partial carbonation keeps Cd leachability below the 1 mg/kg limit, but full carbonation increases it beyond this limit. In contrast, fully carbonated MgO-treated soils maintain Cd leachability below the limit, though partial carbonation leads to higher leachability. Formation of Ca and Mg carbonates contributes to the strength improvement of soils. Cd(OH)2 and its complex, as well as CdCO3 exist in partially and fully carbonated soils, lowering leached Cd concentration. Overall, partial carbonation is better for CaO-treated soils, while full carbonation is preferable for MgO-treated soils.

An easy decision-making graphic tool to improve herd level milk yield in a local scale dairy farming system

Several features prevent dairy farms from reaching their full potential milk yield levels. A plurality of methods are available to analyse a farm’s yield gap, but in practice, farmers rarely use them to understand their main constraints to production. We propose a simple and graphical approach to tune the limiting (feed-related) or reducing (management-related) factors to evaluate the likelihood of being a high-yielding farm. We gathered data from 32 farms within a local-scale dairy system in Northern Italy. Data regarded milk yield (MY), dry matter intake (DMI), feeding ration’s homogeneity index (Hi), feed sorting (Si) index, ration’s geometric mean particle length (GMPL), ration digestibility, income over feed cost (IOFC) and MY summer-winter ratio (SWR). Farms were classified according to their MY levels into high (H) and low or medium (L + M), with a 36.7 kg × cow−1 day−1 threshold. At an ANOVA model for MY class, H farms resulted in higher IOFC (p < 0.001), GMPL (p = 0.046), DMI (p = 0.006), digestible DM (DDM, p = 0.013), digestible crude protein (DCP, p = 0.011), digestible starch (Dstarch, p = 0.001), and feed efficiency (FE, p = 0.003). At a logistic AIC stepwise regression, the GMPL (odds = 6.528, 95% CI = 1.11-64.2) and DMI (odds = 3.889, 95% CI = 1.43-16.5) favoured farms being classified in the H production class. The nomogram was used to calculate a confusion matrix, achieving an overall accuracy of 0.70, demonstrating its ability to transform predictive models into a graphical, realisable tool.

THE EFFECT OF DIFFERENT LIME RATES ON THE YIELD AND QUALITY OF WINTER WHEAT UNDER MINERAL FERTILIZATION ON A SOD-PODZOLIC SOIL

Stable productivity, essential for winter wheat as a strategic crop, can only be achieved by meeting its growth and development requirements, especially nutrition. Soddy-podzolic soils, typically highly acidic in their natural state, are unsuitable for realizing winter wheat's full yield potential. Combined fertilizer and lime application is a key factor for grain yield and quality. While lime (CaCO3) is widely used to reclaim acidic soils, determining the optimal application rate, particularly in combination with mineral fertilizers, is crucial. This research investigated the effect of applying 0,5-2,0 lime norms based on soil hydrolytic acidity (Hh, mmol/100 g) combined with a moderate norm of N60P60K60 mineral fertilizers on winter wheat grain yield and quality. The soil had an initial pHKCl of 4.8 and a hydrolytic acidity of 2,3 mmol/100 g of soil. Field, laboratory, calculation, statistical, and generalization methods were employed. The experiment revealed the lowest grain yield in the control and N60P60K60 treatments without liming. Lime application at various rates with N60P60K60 increased grain yield by 0,74-0,89 t/ha compared to the control, with the 1,5 CaCO3 norm by Hh achieving the best results. The application of 2,0 norms of CaCO3 led to a statistical decrease in yield by 0,14 t/ha (p≤0,05) due to a reduction in available nutrient compounds in the soil. Liming also affected the main indicators of grain quality of winter wheat. An increase to the control was found for the weight of 1000 grains and protein content, while the actual weight of the grain decreased. As the most optimal treatment, regarding grain quality, was found out the option of 1,0 CaCO3 norm based on soil hydrolytic acidity in combination with N60P60K60, with the winter wheat grain yield of 3,54 t/ha and an increase in the protein content in it by 6,8% to the background

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.

Registration of ‘Independence’ switchgrass

AbstractSwitchgrass (Panicum virgatum L.), a valuable forage and bioenergy crop, is established more easily than other native perennial warm‐season grasses, but its establishment is still slower than that of annual crops. Vigorous switchgrass establishment is crucial for achieving its full potential yield and for effectively competing with weeds for water and nutrient availability. To satisfy this demand, ‘Independence’ (Reg. no. CV‐295, PI 704577) switchgrass was developed at the University of Illinois at Urbana‐Champaign. Independence was selected for establishment vigor, winter survivorship, and high biomass yield for two cycles from ‘Kanlow’. It is characterized by rapid establishment, robust seedling growth, and the capacity to achieve peak production by the second year. Independence is well adapted to USDA hardiness zones 5b–7b. In field experiments conducted from 2016 to 2017, averaged over seven locations and all years, Independence annually yielded 13 Mg ha−1 of biomass, outperforming ‘Cave‐in‐Rock’ by 31%, ‘Liberty’ by 15%, ‘Shawnee’ by 42%, ‘Summer’ by 81%, and ‘Sunburst’ by 129%. In wet marginal sites in Illinois from 2020 to 2023, Independence exhibited an average biomass yield of 12 Mg ha−1, outperforming Shawnee by 31%, Liberty by 27%, and Kanlow by 19%, indicating its potential use on less productive land for annual crops. Independence was publicly released by the University of Illinois at Urbana‐Champaign in October 2021.

Boron Impact on Maize Growth and Yield: A Review

Maize (Zea mays L.) is a vital crop, contributing significantly—at least 30%—to global dietary energy intake and biofuels and ethanol production. This review article delves into the dynamic interplay between boron (B) and maize growth, yield, and agricultural sustainability. Boron, a crucial micronutrient, is pivotal in essential physiological processes such as root development, leaf expansion, and cob formation. These processes are fundamental for ensuring the vigour and productivity of maize crops. Conversely, boron deficiency manifests as thinner leaves with reduced chlorophyll content, compromising plant health, and hindering yield potential. Maintaining adequate boron levels, particularly during reproductive stages, is critical for mitigating the risk of abnormal ears and maximizing the quantity and quality of maize production. Emerging research underscores the significance of foliar boron application at various growth stages of maize, which stimulates growth, facilitates cell wall development, and increases leaf area. This translates to improved light interception and photosynthetic efficiency, ultimately contributing to increased plant vigour and biomass accumulation. Furthermore, exploring innovative approaches for sustainable boron management is crucial. This includes precision fertilization techniques and biofortification strategies to ensure optimal maize production while minimizing environmental impacts. By gaining a deeper understanding of the complex relationship between boron and maize, farmers can develop customized fertilization plans that utilize strategic foliar boron application. This approach unlocks maize's full yield potential and contributes to sustainable agricultural practices, supporting global food security.

Coadaptation of coexisting plants enhances productivity in an agricultural system

Growing crops in more diverse crop systems (i.e., intercropping) is one way to produce food more sustainably. Even though intercropping, compared to average monocultures, is generally more productive, the full yield potential of intercropping might not yet have been achieved as modern crop cultivars are bred to be grown in monoculture. Breeding plants for more familiarity in mixtures, i.e., plants that are adapted to more diverse communities (i.e., adaptation) or even to coexist with each other (i.e., coadaptation) might have the potential to sustainably enhance productivity. In this study, the productivity benefits of familiarity through evolutionary adaptation and coevolutionary coadaptation were disentangled in a crop system through an extensive common garden experiment. Furthermore, evolutionary and coevolutionary effects on species-level and community-level productivity were linked to corresponding changes in functional traits. We found evidence for higher productivity and trait convergence with increasing familiarity with the plant communities. Furthermore, our results provide evidence for the coevolution of plants in mixtures leading to higher productivity of coadapted species. However, with the functional traits measured in our study, we could not fully explain the productivity benefits found upon coevolution. Our study investigated coevolution among randomly interacting plants and was able to demonstrate that coadaptation through coevolution of coexisting species in mixtures occurs and promotes ecosystem functioning (i.e., higher productivity). This result is particularly relevant for the diversification of agricultural and forest ecosystems, demonstrating the added value of artificially selecting plants for the communities they are familiar with.

Growth and Nutritional Responses of Zucchini Squash to a Novel Consortium of Six Bacillus sp. Strains Used as a Biostimulant

The use of biostimulants consisting of plant growth-promoting rhizobacteria (PGPR) has been rapidly expanding in horticulture in recent years. In the current study, a novel mix of six Bacillus sp. strains (B. subtilis, B. pumilus, B. megaterium, B. amyloliquefaciens, B. velezensis, B. licheniformis) was tested as a PGPR biostimulant in two experiments with zucchini squash (Cucurbita pepo L.). The first experiment took place in greenhouse soil in winter, while the second experiment was conducted in an open field during summer. In both experiments, seeds of the local landrace “Kompokolokytho” and the commercial hybrid “ARO-800” were either inoculated or non-inoculated with the PGPR biostimulant. The application of the six Bacillus sp. strains increased both the vegetative growth and the yield of zucchini squash, and these effects were associated with significantly higher shoot phosphorus levels in both experiments and both genotypes. Furthermore, at the end of the cultivation, the colony-forming units of Bacillus sp. were appreciably higher in plants originating from inoculated compared to non-inoculated seeds, indicating that the tested mix of Bacillus sp. can be successfully applied through seed inoculation. “ARO-800” produced more vegetative and fruit biomass than “Κompokolokytho” under greenhouse cropping conditions, while in the open field crop, both genotypes performed equally. Presumably, this response occurred because “ARO-800” did not express its full yield potential in the open field due to stress imposed by the high summer temperatures, while the local landrace, which is traditionally grown in open fields, may be more resilient to stress conditions frequently encountered in open fields.

Winter wheat irrigation parameters in the Brazilian Cerrado

Wheat is the second most produced cereal in the world. The gap between production and consumption in Brazil shows that wheat production must be increased to meet the domestic demand. In this context, the objective of this study was to determine the crop coefficient of wheat and the ideal moment for irrigation, based on the soil water depletion rate (f). The study was carried out in the tropics, on an Oxisoil (Typic Haplustox), in an experimental field of Embrapa Cerrados in Planaltina, Federal District of Brazil. The experimental design consisted of randomized blocks with three replications. The treatments were differentiated by the soil water depletion index (f) of 0.2, 0.4, 0.6, and 0.8. In other words, irrigation was initiated when 20, 40, 60 and 80% of the available soil water capacity (AWC) at a soil depth of 0.4 m was consumed by the crop. Wheat yield and yield components were evaluated. The phenological development was monitored based on Zadok’s scale, in days after emergence, and the management parameters crop coefficient (Kc) and irrigation timing were determined. The results indicated a soil water depletion index of 0.4 as the best indicator for beginning wheat irrigation. Under this condition, Kc can be estimated daily as a function of days after emergence (DAE) by the quadratic polynomial regression or curve fitting method, adjusted as follows: Kc = −0.000298 × DAE² + 0.036695 × DAE + 0.332486. Alternatively, the means of Kc of each phenological crop phase can be used: Kc = 0.45 (establishment); 0.81 (tillering); 1.21 (booting); 1.43 (flowering); 1.27 (grain formation); and 0.89 (maturation). Thus, there is a limit of consumption of soil available water, at which wheat still achieves the full yield potential, with a rational use of water which varies according to the development phase.

Productivity and Econometric Analysis of Leguminous Monkey-nut (Arachis hypogaea L.) as Influenced by Growth Retardant

Background: Groundnut (Arachis hypogaea L.) holds significant importance as a staple food legume and a key economic crop, serving as a valuable source of edible oil and protein in India. However, its full yield potential is often hampered by excessive vegetative growth, which leads to suboptimal yields. With this background, a field experiment was conducted at the Perunthalaivar Kamaraj Krishi Vigyan Kendra in Puducherry during 2020 and 2021. The objective was to investigate the influence of different concentrations and timing of paclobutrazol (PBZ) application on the growth and yield of groundnut. Methods: The experiment was laid out in a split-plot design with three replications, six main plot treatments (Including PBZ concentrations of 25, 50, 100, 150, 200 ppm and a control) and three sub-plot treatments (Involving single sprays at 30 days after emergence (DAE), single sprays at 50 DAE and double sprays at 30 and 50 DAE). Result: The results revealed that the application of paclobutrazol at different concentrations had a positive effect on reducing plant height during the later stages of growth, particularly when a double spray was applied at 30 and 50 DAE. Notably, the application of paclobutrazol at a concentration of 200 ppm in groundnut cultivation proved to be economically viable, resulting 29% increase in pod yield compared to the control group. Specifically, PBZ at 200 ppm, with a double spray, significantly boosted the total pod yield to 2724 kg ha-1. Furthermore, the correlation and regression analyses indicated a positive relationship between growth and yield.

ANALISIS PENERAPAN SISTEM PENGUPAHAN BAWON PADA MASA PANEN PADI DALAM PERSPEKTIF EKONOMI ISLAM

The bawon wage system is a system using rice reaping wages, namely (profit sharing). the distribution of bawon is 20% profit sharing for Bawon workers and 80% for rice field owners, the wage system applied in bandar jaya village is 5:1. describes a problem by examining existing data in Bandar Jaya Village, Rantau Rasau District and then analyzing it based on the Islamic Economic Perspective. Using the data collection method, observation, interviews, and documentation were found. From the results of this study, it was found that: (1) in Bandar Jaya Village, the bawon system was considered a very suitable wage system compared to daily and piece rate wages. They considered the value of rice to be more valuable than rice. other than that money for rice that has good quality can be made as seeds. And for owning land the bawon system can reduce the risks that might occur, such as fraud and the quality of work and the bawon system also strengthens the brotherhood of mutual help between landowners and Bawon workers. (2) seen from the Perspective of Islamic Economics The "bawon" wage system that has been used by farmers in Bandar Jaya Village, Tanjung Jabung Timur District, is a rice farming wage system that begins with a work agreement, categorized as valid and justifiable, although there is an element of ambiguity in wages because it is not yet known the full yield of the crop. However, the previous rice field owner was able to estimate the yield he would get. With other considerations, the practice of the bawon/wages contract is valid according to Islamic law because it is in accordance with the rules,

Upscaling rocks mechanical properties to study Underground Hydrogen Storage feasibility

Underground Hydrogen Storage (UHS) is a feasible option for large-scale energy storage considering the advancements of the large-scale production of green hydrogen. One of the main engineering objective is to ensure the continuous safety of the storage, such that subsurface operations can be carried under safe stress regimes. Despite obvious similarities to Carbon Capture and Storage, a few differences make the task a new research challenge.&#x0D; The first one relates to the cyclic nature of UHS, which is expected to be carried at variable frequency and injection/production loads. Current models are not adequate for the lower frequency range considered in this application. In that case, the visco-plastic nature of rocks becomes non-negligible and needs to be taken into account.&#x0D; As a second observation, UHS revolves around a new gas, much lighter than CH4 and super critical CO2. Hydrogen’s atoms are so small they can diffuse even inside rock and this absorption causes rock matrix mechanical properties to weaken. This process is know as Hydrogen Embrittlement. When unaccounted for, such physical phenomenon could lead to catastrophic failure of the caprock, which is supposed to maintain stability to ensure safe storage. The caprock being responsible for the confinement of the hydrogen in the reservoir, development of cracks would enhance greatly permeability of an otherwise impermeable medium, resulting in an environmental disaster as the hydrogen suddenly leaks towards the subsurface and through groundwater aquifers.&#x0D; No empirical model is able to capture those two behaviours at the macro-scale since they are both phenomena principally related to grain-scale physics. As such, this contribution presents a Digital Rock Physics framework to upscale rock mechanical properties from the grain-scale. Rocks of interest are microCT-scanned to extract the digitized microstructure. Direct numerical simulations of elasto-plasticity are performed for different stress paths in order to compute the full yield surface (see Figure 1) instead of just the Uniaxial Compressive Strength. While most studies use Discrete Element Modelling to consider grain contacts explicitly, our simulator uses Finite Element Modelling which allows more flexibility in the approach to model multiphysics processes present during UHS. The contacts are modelled instead as an upscaled plastic law. Details of the numerical algorithms are presented in [1].&#x0D; As a first case study for this framework, we present a comprehensive parametric study on the impact of cementation on rock strength for real microstructures of granular materials. The framework is then coupled with a numerical erosion algorithm that simulates homogeneous precipitation of mineral matter to represent cementation. New results on the influence of cement property namely Young’s modulus, friction and cohesion on the rock’s yield surface are explored. This study contributes to preliminary results on Hydrogen Embrittlement which directly influences those same mechanical properties. However more work is needed to model realistically the Hydrogen Embrittlement, which is the aim of our new PhD project OCEAN. The process will be observed experimentally at the micro-scale in order to calibrate the simulator. MicroCT-scan images will determine the spatial distribution of the phenomenon. Visco-plasticity will be implemented from [2] to go one step further and determine the effect of Hydrogen Embrittlement during cyclic injection/production of hydrogen.

Model-based scenarios for achieving net negative emissions in the food system

Most climate mitigation scenarios point to a combination of GHG emission reductions and CO2removal for avoiding the most dangerous climate change impacts this century. The global food system is responsible for ~1/3 of GHG emissions and thus plays an important role in reaching emission targets. Consumers, technology innovation, industry, and agricultural practices offer various degrees of opportunity to reduce emissions and remove CO2. However, a question remains as to whether food system transformation can achieve net negative emissions (i.e., where GHG sinks exceed sources sector wide) and what the capacity of the different levers may be. We use a global food system model to explore the influence of consumer choice, climate-smart agro-industrial technologies, and food waste reductions for achieving net negative emissions for the year 2050. We analyze an array of scenarios under the conditions of full yield gap closures and caloric demands in a world with 10 billion people. Our results reveal a high-end capacity of 33 gigatonnes of net negative emissions per annum via complete food system transformation, which assumes full global deployment of behavioral-, management- and technology-based interventions. The most promising technologies for achieving net negative emissions include hydrogen-powered fertilizer production, livestock feeds, organic and inorganic soil amendments, agroforestry, and sustainable seafood harvesting practices. On the consumer side, adopting flexitarian diets cannot achieve full decarbonization of the food system but has the potential to increase the magnitude of net negative emissions when combined with technology scale-up. GHG reductions ascribed to a mixture of technology deployment and dietary shifts emerge for many different countries, with areas of high ruminant production and non-intensive agricultural systems showing the greatest per capita benefits. This analysis highlights potential for future food systems to achieve net negative emissions using multifaceted “cradle-to-grave” and “land-to-sea” emission reduction strategies that embrace emerging climate-smart agro-industrial technologies.

Evaluation of yield attributing characters and grain yield in some promising red rice lines (Oryza sativa L.) grown in the lowland conditions

The research experiment conducted on the farmer paddy field in Ranomeeto village, District of South Konawe, Indonesia from January to May 2022, to evaluate the yield attributing characters and the grain yield in some new promising lines or cultivar of red rice. The red rice lines tested are GS12-1, GS12-2, GS16-1, GS16-2, GS44-1, and control variety Inpari-33, were laid out and arranged in field using randomized complete block design (RCBD) in three replications. The parameter measured were plant height, tiller density, productive tiller density, flowering time, harvesting times, panicle length, panicle density, filled grain percentage, 1000-grain weight, and grain yield. Differences between promising lines of red rice were found to exist when data on various yield-attributing features and grain yield were analysed. GS16-1 (89.37 cm) was the tallest plant and GS12-2 the shortest (72.74 cm). GS16-2 had the longest panicle (25.96 cm) and most grains per panicle (146.62). GS44-1 full grains, 1000-grain weight, and grain yield were highest. G12-1 lines had the most productive tillers, days to flowering, and harvest. Tiller number and productivity are positively correlated (0.908**). Tillers, productive tillers, and full grains percentage positively affect grain yield per plant.

Variable Yield Responses among Grafted and Nongrafted Late blight–resistant Tomato (Solanum lycopersicum L.) Hybrids in North Carolina

Host resistance is an environmentally and economically sustainable disease management strategy that may be especially beneficial to small-scale and organic growers for whom other management tools such as synthetic pesticides are too costly or not permitted. In western North Carolina, the demand for vine-ripened tomatoes (Solanum lycopersicum L.) from local and organic farms has led to the development of cultivars bred for resistance to geographically relevant diseases, including late blight of tomato, which causes rapid defoliation and lesions on fruit. Grafting tomato plants has the potential to increase plant vigor and yield; however, this effect is known to be dependent on multiple factors, including scion and geographic location. In this study, we evaluated the yield response of one determinate (‘Mountain Gem’) and four indeterminate (‘Mountain Heritage’, ‘Mountain Girl’, ‘Mountain Rouge’, and ‘NC10291’) late blight–resistant tomato cultivars, grafted on tomato rootstock ‘Maxifort’ or nongrafted, on a commercial farm and at two research facilities in western North Carolina. Yield of marketable fruit from grafted plants was greater than that from nongrafted plants at one location (P = 0.008); however, yield response of each cultivar, grafted or not grafted, differed by location. Yield was consistently greater from ‘Mountain Gem’ plants than other cultivars, and grafted ‘Mountain Gem’ plants had greater yields later in the season at two locations than nongrafted plants. Because of the late planting date intended to expose cultivars to the late blight pathogen, the full yield potential of the indeterminate cultivars was not realized at all locations. Disease severity caused by Verticillium wilt (Verticillium dahliae Kleb., Verticillium albo-atrum Reinke &amp; Berthold) was lowest for cultivar Mountain Heritage at two of three locations. Results from this study emphasize the importance of conducting evaluations of grafted tomato plants at multiple locations, including on farm, to optimize the benefits associated with their use.

Optimizing nitrogen fertilization for hybrid canola (Brassica napus L.) production across Canada

Context or problemHybrids are currently the dominant varieties in canola production, but their yield response to nitrogen (N) application across Canada has not been adequately updated. As a result, there is a lack of effective N management guidelines for modern hybrid canola to reach their full yield potential and cope with growing abiotic stresses caused by climate change. Objectives or research questionsThis study was designed to investigate the responses of yield and N use efficiency (NUE) of modern canola hybrids to N fertilization for determining site-specific economic optimum N rates (EONR). Additionally, the key driving factors of canola yields and N recommendations were identified. MethodsA 32 site-year field study across Canada was conducted to test 8 combinations of N rates and application methods on 2 site-specific hybrids in each trial. ResultsNitrogen fertilization greatly increased canola yield by an average of 41%, with significant responses in 19 out of 32 trials. Split-N strategy led to similar yield, NUE, and yield response index compared to preplant-only N application. However, these traits varied among hybrids due to different growing environments and hybrid-specific tolerance to abiotic stresses. The number of heat-stress days and heat-induced thermal accumulation surrounding the 4 weeks before and post-flowering stage directly determined the canola responses to N fertilization and EONR. ConclusionsOur results suggest a site-specific EONR of 146–166 kg N ha−1 in the Black soil zone, 85–100 kg N ha−1 in the low-yielding Brown soil zone, and 140 kg N ha−1 in Ontario, preferably with a split-N strategy for hybrid canola production. The split-N fertilization is generally recommended, as it provides an opportunity to adjust the amount of topdressing N based on historical and early season weather conditions to achieve the dual goals of increasing canola productivity and reducing greenhouse gas (GHG) emissions from fertilizer use. The energy and time costs must be considered when making practical decisions. Environment-specific selection of canola hybrids also played an important role in the response to N, with ‘6074RR’ in favorable weather and ‘L233P’ in drought-prone conditions appearing to be good choices for specific ecoregions.

PENGARUH TEMPERATUR DAN TEKANAN TERHADAP HASIL CETAKAN POLYPROPYLENE MENGGUNAKAN MESIN INJECTION MOLDING VERTIKAL

Currently, the use of plastic products is increasing in various fields, due to their flexibility and low production costs. The injection molding process is a technique that is often used in the formation of plastic products. The focus of the problem of this study is the effect of heating temperature and hydraulic pressure on the results of box and gear molds using the injection molding process. The test method uses variations in temperature and hydraulic pressure to produce the maximum mold shape in the box and gear. From the results of the injection molding test for full yield gear products with a melt temperature of 368ºC, a mold temperature of 40ºC, and an injection pressure of 490 Psi, there was a failure in the test results due to the release of liquid which did not come out directly to fill the mold, because the pressure from the hydraulic jack must gradually.

Yield criteria for voided materials with anisotropic matrix behavior

This paper presents a theoretical and micromechanical procedure for determining the macroscopic behavior of voided materials with anisotropic matrix constitutive behavior. Within the Gurson approach (Gurson, 1977), it combines the IPE (Isotropy Plasticity Equivalent) concept proposed by Karafillis and Boyce (1993) to the procedure proposed by Benallal (2017) to build macroscopic behavior of voided materials with general isotropic matrix behavior. For sake of clarity, the simple Gurson kinematically admissible velocity field is used and can be replaced by any more suitable trial field. The matrix may have any anisotropic behavior represented by the linear transformation of the IPE setting, which is traceless. A general parametric constitutive relation is obtained for the six-dimensional yield surface of the porous solid. A numerical algorithm is then proposed to evaluate and visualize arbitrary sections of this full six-dimensional macroscopic yield surface and various illustrations are provided for different matrix plastic constitutive behavior including Lode angle effects and materials symmetries. Some qualitative aspects of the macroscopic yield locus are summarized and discussed.