English (United Kingdom)

https://curated-unify.zendy.io/wp-json/zendy-region/v1/featured_content/oa?rat=en

https://curated-unify.zendy.io/wp-json/zendy-region/v1/highlighted_journal/

Global: Zendy Plus annual

Presents the access of premium content as premium feature

Premium Content

Presents the keyphrase highlighting as premium feature

Keyphrase Highlighting

Presents the summarisation as premium feature

Summarisation

Insights

Presents the pdf analysis as premium feature

PDF Analysis

Presents the zaia usage as premium feature

ZAIA

Global: Zendy Tools annual

Global: Zendy Free Plan

Global: Zendy Tools monthly

Global: Zendy Plus monthly

Substrate solution testing is an essential management tool for greenhouse plug production. Current methods of plug solution extraction error, the recommendations are to test substrate pH and soluble salts or electrical conductivity (EC) frequently (Fonteno et al., 1995). Nearly 80% of nutritional problems are due to fluctuations in substrate pH and soluble salts levels that should be monitored on a regular basis (Styer, 1996). However, the rapid production cycle for most plugs of 3 to 5 weeks (from seed to transplant) negates the usefulness of analysis if a lengthy turnaround is involved, as is often the case with analytical laboratories. Thus, there is a need to develop a dependable, yet quick, method of substrate solution extraction (Bunt, 1986) that can be implemented on a regular basis by plug growers. Analysis of the true, displaced solution best assesses the nutrient status of the growth substrate (Bunt, 1986). The press extraction method (PEM) is a variation of the “squeeze” method introduced by Fonteno et al. (1995). The substrate is brought to container capacity and not further diluted. Pressing the top of the plug and collecting the expelled solution provides an extract that closely resembles the root zone solution. Solution pH and EC can be determined within minutes, and the extracted solution can be sent on to an analytical laboratory for nutrient testing. The objective of these experiments was to quantify how extraction force may affect solution chemical properties. We investigated the effect of extraction force on solution pH and EC initially with one fertilizer concentration, then over a range of concentrations. We also examined the effect of variable force on the nutrient analysis of coir, an alternative substrate component.

horttechnology

Development of the Press Extraction Method for Plug Substrate Analysis: Effects of Variable Extraction Force on pH, Electrical Conductivity, and Nutrient Analysis