Does foliar nicotinamide application affect second crop corn (Zea mays)?

The largest corn yeld in Brazil is currently in the second harvest, which is the most susceptible period to climatic adversities occurring during the cycle. Thus, introducing beneficial elements for maintaining the adequate development of the plant can help producers in obtaining greater kernel yields. Among studied elements, nicotinamide has potential use since it is associated with accumulating secondary metabolites and manifesting defence metabolism in plants. The objective of this work was to evaluate the influence of nicotinamide applied in different doses (only once or in instalments) on the biometric and productive characteristics of corn. The treatments were composed by the number of nicotinamide applications (one or two) and five doses (0, 50, 100, 150 and 200 mg L-1). Plant diameter, plant height, ear insertion height, leaf area and dry matter, yield and 100-kernel mass were evaluated. It was found that doses close to 100 mg L-1 resulted in increases in vegetative and reproductive development, regardless of the number of applications. In this way, foliar nicotinamide application positively influences the biometric and productive characteristics of second crop corn. Highlights The use of nicotinamide in corn plants improves its growth, yield components and grain yield. A single application of nicotinamide during vegetative stage V3 at a dose of 100 mg L-1 is sufficient to increase the leaf area of corn plants. Corn grain yield can be increased by 12.6% with a single application of nicotinamide. There was no need for two applications of nicotinamide in corn crop.

Modifications to the delivery of NHS face-to-face general practice consultations during the COVID-19 pandemic in England

Background: In order to minimise transmission of SARS-CoV-2, the virus causing COVID-19, delivery of English general practice consultations was modified in March 2020 to enable the separation of patients with diagnosed or suspected COVID-19 from others. Remote triage and consultations became the default, with adapted face-to-face contact used only when clinically necessary. Face-to-face delivery modifications were decided locally and this study aimed to identify the different models used nationwide in spring/summer 2020. Methods: In June 2020, a survey was sent by email to the 135 Clinical Commissioning Groups (CCGs) responsible for planning and commissioning NHS health care services in England to identify the local organisation of face-to-face general practice consultations since March 2020. Results: All CCGs responded. Between March and July 2020, separation of patients with diagnosed or suspected COVID-19 (‘COVID-19 patients’) from others was achieved using the following models: zoned practices (used within 47% of CCGs), where COVID-19 and other patients were separated within their own practice;‘hot’ or ‘cold’ hubs (used within 90% of CCGs), separate sites where COVID-19 or other patients registered at one of several collaborating practices were seen;‘hot’ and ‘cold’ home visits (used within 70% of CCGs). For around half of CCGs, either all their GP practices used zoning, or all used hubs; in other CCGs, both models were used. Demand-led hub availability offered flexibility in some areas. Home visits were mainly used supplementally for patients unable to access other services, but in two CCGs, they were the main/only form of COVID-19 provision. Conclusions: Varied, flexible ways of delivering face-to-face general practice consultations were identified. Analysis of the modified delivery in terms of management of COVID-19 and other conditions, and other impacts on staff and patients, may both aid future pandemic management and identify beneficial elements for practice beyond this.

Modifications to the delivery of NHS face-to-face general practice consultations during the COVID-19 pandemic in England

Background: To minimise transmission of SARS-CoV-2, the virus causing COVID-19, delivery of English general practice consultations was modified in March 2020 to enable separation of diagnosed or suspected COVID-19 patients from others. Remote triage and consultations became the default, with adapted face-to-face contact used only when clinically necessary. This study aimed to identify the modified face-to-face delivery models used nationwide in spring/summer 2020. Information was also sought concerning COVID-19 outbreaks linked to English general practice. Methods: In June 2020, a survey was sent by email to the 135 Clinical Commissioning Groups (CCGs) in England to identify local organisation of face-to-face general practice consultations since March 2020. An email was sent to Public Health England (PHE) requesting data on COVID-19 outbreaks linked to general practice. Results: All CCGs responded. Between March and July 2020, separation of COVID-19 patients from others was achieved using combinations of the following models: zoned surgeries (reported by 47% of CCGs), where COVID-19 and other patients were separated within their own practice;‘hot’ or ‘cold’ hubs (reported by 90% of CCGs), separate sites where COVID-19 or other patients registered at one of several collaborating practices were seen;‘hot’ and ‘cold’ home visits (reported by 70% of CCGs). One of seven combinations of these models was used across each CCG, with some flexibility shown according to changing demand through hub availability. PHE data indicated 25 possible or confirmed COVID-19 outbreaks or clusters in English general practice to July 31st 2020. Conclusions: Varied, flexible ways of delivering face-to-face general practice consultations were identified. Analysis of the modified delivery in terms of management of COVID-19 and other conditions, and impacts on staff and patients, together with learning from investigations into confirmed COVID-19 outbreaks, may both aid future pandemic management and identify beneficial elements for practice beyond this.

Interactions of Silicon With Essential and Beneficial Elements in Plants

Silicon (Si) is not classified as an essential element for plants, but numerous studies have demonstrated its beneficial effects in a variety of species and environmental conditions, including low nutrient availability. Application of Si shows the potential to increase nutrient availability in the rhizosphere and root uptake through complex mechanisms, which still remain unclear. Silicon-mediated transcriptional regulation of element transporters for both root acquisition and tissue homeostasis has recently been suggested as an important strategy, varying in detail depending on plant species and nutritional status. Here, we summarize evidence of Si-mediated acquisition, uptake and translocation of nutrients: nitrogen (N), phosphorus (P), potassium (K), calcium (Ca), magnesium (Mg), sulfur (S), iron (Fe), zinc (Zn), manganese (Mn), copper (Cu), boron (B), chlorine (Cl), and nickel (Ni) under both deficiency and excess conditions. In addition, we discuss interactions of Si-with beneficial elements: aluminum (Al), sodium (Na), and selenium (Se). This review also highlights further research needed to improve understanding of Si-mediated acquisition and utilization of nutrients and vice versa nutrient status-mediated Si acquisition and transport, both processes which are of high importance for agronomic practice (e.g., reduced use of fertilizers and pesticides).

Se Changed the Component of Organic Chemicals and Cr bioavailability in Pak Choi Rhizosphere Soil Contaminated with Cr

Rhizosphere organic chemicals response and its role on Cr/Se adsorption is of great importance to understand Cr/Se bioavailability in Cr contaminated soil with the application of Se. In the current work, the processes were carried out using rhizobox experiment (Brassica campestris L. ssp. Chinensis Makino). The results showed that in soil contaminated by 200 mg kg-1 Cr(III), Se(Ⅳ) complexed with Cr(Ⅲ) and carboxylic acid (cis-9,10-Epoxystearic acid, hexadecanedioic acid) reduced Cr(Ⅵ) to Cr(Ⅲ), thus increasing of Cr adsorption, furtherly, decreasing Cr bioavailability. While, in soil contaminated by 120 mg kg-1 Cr(Ⅵ), Se(Ⅵ) competed for adsorption sites with Cr(Ⅵ) and salicylic acid activated insoluble Cr(III), thus decreasing Cr adsorption, finally, increasing Cr bioavailability. Moreover, with Cr contamination, Se bioavailability in soil was enhanced by the secretion of carboxylic acid, which can reduce Se to lower valent state, compete the adsorption sites and complex with Se oxyanion. These results yielded a better understanding of rhizosphere dynamics regulating by Se application in Cr contaminated soil. Moreover, the current study supplemented the theoretical basis for beneficial elements application as an environment-friendly resource to facilitate cleaner production in heavy metal contaminated soil.

Effect of Silicate Fertilizer on the Growth and Yield of Two Local Indonesian Varieties of Rice (Oryza sativa L.)

Background: The beneficial elements availability such as silicon was determined rice growth and yield. Rice requires a different dose of silicon during the growing period. Experiment was aimed to investigate the effect of silicate levels, rice varieties and the interaction of the two on the growth and yields of two local Indonesian varieties of rice. Methods: A completely randomized design of factorial pattern with 4 replications was used in the experiment. Treatments consisted of No added SiO2 (Si-0); added 100 and 200 kg SiO2 ha-1, respectively for Si-100 and Si-200 and two local rice varieties, Pandan wangi (P1) and Mentik susu (P2). Result: The treatment had no significant effect on growth and yield of rice. Addition of 100 and 200 kg SiO2 ha-1 to P1 and P2 did not show a significant difference on the growth and yield of rice compared to control (P0). Plant height and root dry weight at P1 was lower than P2, but the 1,000-grain weight was showed, vice versa. Silicon addition up to 200 kg SiO2 ha-1 may not be recommended to be applied in rice cultivation, especially Pandan wangi and Mentik susu varieties. Improving the two varieties, further research is needed by increasing the silicon doses.

Plant nutrition and nutrient formulation.

This chapter focuses on plant nutrition and nutrient formulation. Water quality and sources for hydroponic production, reclaimed water sources, water testing, water analysis reports, water treatment options, water usage and supply requirements, plant nutrition in hydroponic systems, essential elements and its function in plants and deficiency symptoms, beneficial elements, nutrient formulation, hydroponic nutrient formulation - nitrogen sources, common hydroponic fertilizers, fertilizer composition and grades, chelation of trace elements, foliar fertilizers, electrical conductivity, pH, conditions which affect nutrient uptake rates, automation and testing equipment, plant tissue analysis, fertilizer and environmental concerns, water and nutrient solution treatment methods, and surfactants are the topics discussed in this chapter.