Influence of Seed Coat Integrity on the Response of Pepper Seeds to Dielectric Barrier Discharge Plasma Treatment

Abstract

This study investigated the response of pepper seeds with varying seed coat conditions (SCs) to dielectric barrier discharge plasma treatment (PT). The experimental design was a split plot with three replications. The primary plot factor was the SC (normal seeds [NMS], nicking at the hilum part [NHP], and removed seed coat [RSC]), while the subplot factor was the plasma exposure time (0.4–2.0 s/cm), including a control, to determine the effects on seed viability, germination, and vigor. The results indicate that NMS seeds exhibit the highest performance in terms of seed viability. The NMS and NHP had statistically significantly higher seed germination, electrical conductivity, radical emergence, and germination index at 14 days after sowing, and the shoot length measured longer than RSC. Plasma exposure at 1.2 s/cm improved germination and vigor, whereas 2.0 s/cm exposure significantly decreased seed viability and increased the number of abnormal seedlings. The interaction between SC and PT significantly affected seedling abnormalities, with RSC seeds being more vulnerable to damage under prolonged exposure. These findings highlight the crucial role of seed coat integrity in maintaining seed quality and suggest that carefully controlled PT can be a promising and sustainable method to enhance pepper seed performance.