Published in Scientific Papers. Series A. Agronomy, Vol. LXIX, Issue 1
Written by Elena NICOLAE, Valentina VASILE, Costică CIONTU
This study presents a comprehensive six-year analysis (2019-2024) of inter-laboratory analytical variability across Romania's 30-laboratory seed testing network through 11 biannual proficiency testing rounds. Following ISTA Standard Proficiency Test (PT-P-01) methodology, the research examined all three purity components across 11 crop species representing diverse ISTA crop groups. Mathematical analysis revealed that while overall physical purity demonstrated exceptional standardization (mean CV 0.36%), constituent components exhibited dramatically different variability
patterns due to mathematical amplification effects in constrained compositional systems. Inert matter showed extreme variability (mean CV 70.7% - 197-fold higher than purity), other seeds demonstrated intermediate variability (CV 32.0% - 89-fold higher), while pure seed maintained exceptional consistency. This component-specific analysis reveals that traditional purity-focused proficiency testing masks substantial analytical complexity at component level. Z-score analysis confirmed outstanding network competency (95.45% excellent ratings), validating that observed variability
reflects mathematical constraints and biological factors rather than analytical incompetence. The study demonstrates that mechanical separation methodology achieves chemical-procedure precision under quality-assured conditions, while providing new insights into compositional data analysis for seed testing networks.
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{simplepopup popup="false" name="Citation55"}NICOLAE E., VASILE V., CIONTU C. 2026, COMPARATIVE STUDY ON ANALYTICAL VARIABILITY OF PHYSICAL PURITY IN SEED TESTING LABORATORIES. Scientific Papers. Series A. Agronomy, Vol. LXIX, Issue 1, ISSN 2285-5785, 449-458. {/simplepopup}