Comparison of different selection traits for identification of phosphorus use efficient lines in mungbean

Phosphorus (P) is one of the major constraints for crop growth and development, owing to low availability and least mobility in many tropical soil conditions. Categorization of existing germplasm under P deficient conditions is a prerequisite for the selection and development of P efficient genotypes in the mungbean. In the present investigation, 36 diverse genotypes were categorized for phosphorus use efficiency traits using four different techniques for identification of phosphorus use efficient mungbean genotypes. The studied genotypes were categorized for P efficiency based on efficiency, responsiveness, and stress tolerance score of genotypes under normal and low P conditions. The mean values of traits, root dry mass, root to shoot ratio, and P utilization efficiency are significantly higher under low P conditions indicating the high responsiveness of traits to P deficiency. The presence of significant interaction between genotypes and P treatment indicates the evaluated genotypes were significantly affected by P treatment for studied traits. The total P uptake showed significant and positive correlations with root dry mass, shoot dry mass, total dry mass,and P concentration under both P regimes. Out of the four techniques used for the categorization of genotypes for P efficiency, three techniques revealed that the genotype PUSA 1333, followed by Pusa Vishal, PUSA 1031, and Pusa Ratna is efficient. The categorization based on stress tolerance score is the finest way to study variation and for the selection of contrasting genotypes for P efficiency. The identified P efficient genotypes would be valuable resources for genetic enhancement of P use efficiency in mungbean breeding.

Optimizing Casing Cut and Pull Operations Efficiency Using Ultrasonic Logging Data

Thousands of wells will enter the plug and abandonment (P&A) phase across the Norwegian Continental Shelf (NCS), either for permanent well abandonment or section abandonment with subsequent sidetracks. In the medium and long term, more wells will be added to follow the same path as exploration, drilling, and production continues. The cost of abandonment operations demands improvement of how P&A operations are performed. A critical, and often time-consuming operation, of well or section abandonment is to cut and pull (C&P) some of the casing strings. Uncertainties about the status of the annular contents and the material within it, such as settled solids, contaminated cement, or well geometry might pose restraints that could hinder the C&P efficiency. The uncertainties may cause operations to deviate from the plan, increasing the time and the costs required. New-generation ultrasonic tools, in combination with sonic tools, provide information about the annulus material with a detailed map of the axial and azimuthal variations of the annulus contents. The geometric position of the inner pipe can be determined relative to the outer casing or borehole using advanced measurements. Logging with ultrasonic and sonic tools is a noninvasive method that can increase the efficiency of C&P operations. In this paper we discuss three case studies of wells ranging from 2 to 40 years old. Some of the wells have reached the end of their economic life and are now ready for permanent plug and abandonment (PP&A) or slot recovery. Each case is unique with different casing sizes being retrieved, along with varied annulus contents observed from ultrasonic and sonic log data. The innovative use of the data interpretation with advanced workflows decreased uncertainties about the annulus contents and enabled following an informed C&P strategy. In all three cases, the casing sections were retrieved without difficulties from the recommended depths of the analysis. Casing milling was performed in intervals where C&P was not supported by the data analysis.

Evaluating Heritability and Relationships among Phosphorus Efficiency Traits in Maize under Low P Soils of Western Kenya

Low available phosphorus (P) remains a major limitation to maize (Zea mays L.) productivity across the world. Selection for P efficiency is key as part of strategies to achieving agricultural sustainability. The objectives of this study were to: (i) determine the phenotypic and genetic relationships among P-efficiency traits in maize under low P soils and (ii) determine the heritability of some of these traits under similar conditions. A total of 32 experimental maize hybrids were evaluated for tolerance to low P in a replicated trial at four locations for one season. The experiment was laid out in a split plot arrangement in RCBD replicated 3 times across two P levels (36 kgP/ha and 6 KgP/ha). Grain yield had the highest correlation (r= 0.44-0.95) with most P- efficiency traits at both P conditions. It also exhibited high positive and significant correlations with plant height (rg = 0.72**) ear height (rg = 0.54*), cob Length (rg =0.81**) and stover yield (rg = 0.61**) while it was negatively correlated with days to anthesis and silking. The correlation between grain and shoot P concentration and grain P content with majority of the P efficiency indices (P acquisition &Utilization efficiencies &P efficiency) at both P levels was low & tended to be negative and non-significant indicating that seed P reserve, and stover P concentration, had minimal contribution to differential P efficiency. However, the relationship between shoot P content with P-efficiency traits was significant (r= 0.51-0.95), suggesting that shoot P content is a useful parameter in selecting for P efficiency in maize. Moderate to high heritability (0.50-0.95) was observed for the various traits showing that a large proportion of the observed variations were due to genetic differences among the hybrids. This study has determined genetic and phenotypic associations among P selection parameters that can help in flexing the selection methodologies to suite unique circumstances and environments.

Optimizing the P balance: How do modern maize hybrids react to different starter fertilizers?

Phosphorus (P) is an essential macronutrient for plants, but also a limited resource worldwide. Strict regulations for fertilizer applications in the European Union are a consequence of the negative environmental effects in case of improper use. Maize is typically grown with the application of P starter fertilizer, which, however, might be reduced or even omitted if suitable varieties were available. This study was performed with the 20 commercially most important maize hybrids in Germany evaluated in multi-location field trials with the aim to investigate the potential to breed for high-performing maize hybrids under reduced P starter fertilizer. At the core location, three starter fertilizers with either phosphate (triple superphosphate, TSP), ammonium nitrate (calcium ammonium nitrate, CAN), or a combination of ammonium and phosphate (diammonium phosphate, DAP) were evaluated relative to a control and traits from youth development to grain yield were assessed. Significant differences were mainly observed for the DAP starter fertilizer, which was also reflected in a yield increase of on average +0.67 t/ha (+5.34%) compared to the control. Correlations among the investigated traits varied with starter fertilizer, but the general trends remained. As expected, grain yield was negatively correlated with grain P concentration, likely due to a dilution effect. Importantly, the genotype-by-starter fertilizer interaction was always non-significant in the multi-location analysis. This indicates that best performing genotypes can be identified irrespective of the starter fertilizer. Taken together, our results provide valuable insights regarding the potential to reduce starter fertilizers in maize cultivation as well as for breeding maize for P efficiency under well-supplied conditions.

Population structure and genome-wide association studies in bread wheat for phosphorus efficiency traits using 35 K Wheat Breeder’s Affymetrix array

Soil bioavailability of phosphorus (P) is a major concern for crop productivity worldwide. As phosphatic fertilizers are a non-renewable resource associated with economic and environmental issues so, the sustainable option is to develop P use efficient crop varieties. We phenotyped 82 diverse wheat (Triticum aestivum L.) accessions in soil and hydroponics at low and sufficient P. To identify the genic regions for P efficiency traits, the accessions were genotyped using the 35 K-SNP array and genome-wide association study (GWAS) was performed. The high-quality SNPs across the genomes were evenly distributed with polymorphic information content values varying between 0.090 and 0.375. Structure analysis revealed three subpopulations (C1, C2, C3) and the phenotypic responses of these subpopulations were assessed for P efficiency traits. The C2 subpopulation showed the highest genetic variance and heritability values for numerous agronomically important traits as well as strong correlation under both P levels in soil and hydroponics. GWAS revealed 78 marker-trait associations (MTAs) but only 35 MTAs passed Bonferroni Correction. A total of 297 candidate genes were identified for these MTAs and their annotation suggested their involvement in several biological process. Out of 35, nine (9) MTAs were controlling polygenic trait (two controlling four traits, one controlling three traits and six controlling two traits). These multi-trait MTAs (each controlling two or more than two correlated traits) could be utilized for improving bread wheat to tolerate low P stress through marker-assisted selection (MAS).

Phosphate Uptake and Transport in Plants: An Elaborate Regulatory System

Phosphorus (P) is an essential macronutrient for plant growth and development. Low phosphate (Pi) availability is a limiting factor for plant growth and yield. To cope with a complex and changing environment, plants have evolved elaborate mechanisms for regulating Pi uptake and use. Recently, the molecular mechanisms of plant Pi signaling have become clearer. Plants absorb Pi from the soil through their roots and transfer Pi to various organs or tissues through phosphate transporters, which are precisely controlled at the transcript and protein levels. Here, we summarize the recent progress on the molecular regulatory mechanism of phosphate transporters in Arabidopsis and rice, including the characterization of functional transporters, regulation of transcript levels, protein localization, and turnover of phosphate transporters. A more in-depth understanding of plant adaptation to a changing Pi environment will facilitate the genetic improvement of plant P efficiency.

Delivering improved phosphorus acquisition by root systems in pasture and arable crops

Improving low efficiency of phosphorus (P) use in agriculture is an imperative because P is one of the key nutrients underpinning sustainable intensification of food production and the rock-phosphate reserves, from which P fertilisers are made, are finite. This paper describes key soil, root and microbial processes that influence P acquisition with a focus on factors that can be managed to ensure optimal use of fertiliser, and development of root systems for improved P acquisition. A case study describes grasslands in southern Australia where the P-balance efficiency of production is very low, mainly because soils are P deficient and moderately to highly P-sorbing. Use of soluble P fertiliser, P-banding and soil testing to guide soil P management ensures effective use of P fertiliser. Progress towards improved P efficiency using pasture legumes with high P-acquisition efficiency is outlined. Development of a ‘whole-of-system’ understanding for effective P acquisition by roots is highlighted.

Variantenmanagement in Entwicklung und Produktion/Variant management in engineering and production

Aufgrund der zunehmend individualisierten Nachfrage bieten Hersteller ihren Kunden die Möglichkeit Produkte zu konfigurieren. Daraus ergibt sich eine hohe Variantenvielfalt, die oft nur mit komplexen Prozessen abbildbar ist. Um die Wirtschaftlichkeit sicherzustellen, muss der Umgang mit Produkt- und Produktionsvielfalt optimiert werden. In diesem Ansatz werden ein Datenmodell und softwarebasierte Werkzeuge zur ganzheitlichen Planung und Kontrolle von Zielen und deren Umsetzung im Variantenmanagement entwickelt. Dadurch wird die vorhandene Variantenvielfalt transparent und die Durchführung von Maßnahmen zur Variantenreduktion möglich.   Due to increasingly individualized demand, manufacturers provide customers with the option to configure products. Often, this results in a high number of variants that only can be managed with complex processes. To ensure economic   efficiency it is necessary to optimize the handling of product and production variety. This approach develops a data model together with software-based tools to allow for the holistic planning and controlling of goals and their implementation in variant management. This makes the existing variant diversity visible and enables the implementation of measures to reduce variants.

Highly Efficient and Robust Catalysts for Hydrogen Evolution Reaction by Surface Nano Engineering of Metallic Glass

Efficiency and stability are the key parameters for hydrogen evolution reaction (HER) of water electrolysis, thereby developing effective and robust catalysts have been long standing pursuits. In this work, we...

Luminance efficiency roll-off mechanism in CsPbBr3−xClx mixed-halide perovskite quantum dot blue light-emitting diodes

Efficiency roll-off is a significant issue in blue light-emitting diodes (LEDs), but its origin still remains controversial.