Evaluation of Quick Assessment Method for Mechanical Damage in Soybean Seed

Abstract

Mechanical damage plays an important role in seed quality. According to high protein and oil components, soybean seed becomes fragile during harvesting and processing, resulting in reduced seed yield and quality. Mechanical damage to the seed is monitored after threshing and processing to reduce loss of quantity and quality. Although the Indoxyl acetate (IDA) test is recommended for mechanical soybean seed damage detection, it is complicated, expensive, and difficult to apply in the field. Therefore, quick assays were conducted on 15 soybean (cv. DOA Chiangmai 60) seed lots to detect mechanical damage to soybean seed, namely fast green (FG), ferric chloride (FC), and sodium hypochlorite (SDH), and the results were then compared with the IDA method. The germination and vigor—as measured by accelerated aging tests—ranged from 71% to 90% and 46% to 86%, respectively. The average mechanical damage to 15 seed lots tested by IDA equated to 7.9%, significantly different from FG (11.3%), FC (11.2%), and SDH (11.6%) methods determined by the paired t-test. The correlation coefficient (r) and linear regression (R²) among mechanical damage methods were analyzed, with the greatest significance found between IDA and SDH. Although the mechanical damage determined by SDH was significantly higher than IDA, this method revealed the closest relationship with IDA and exhibited the moderate negative correlation with germination, as well as being the easiest, cheapest, and most feasible for soybean seed cv. DOA Chiangmai 60 application in the field compared to other methods.