Accelerated aging test and image analysis for barley seed

Barley ('Hordeum vulgare' L.) planted area has increased in Brazil after a decline from 2005-2009, but the country continues to import malt for the brewing industry. The physiological quality of the seed lot is essential for plant establishment and for screening for high yield grain. However, a uniform accelerated aging (AA) procedure has not been developed for testing barley seeds. Thus, this study aimed to determine the best AA method for measuring barley seed vigor. Seeds of three barley cultivars (BRS Caue, BRS Brau, and MN 6021) were subjected to four AA treatment (T1: 41 degreesC for 72 h; T2: 42 degreesC for 48 h; T3: 42 degreesC for 60 h; and T4: 43 degreesC for 48 h). The following variables were evaluated using traditional vigor tests: seed viability in the first and last count of the germination test, number of seminal roots, shoot length, and radicle length. In addition, digital images of seedlings were acquired with the Seed Analysis System (SAS) to compute seedling vigor, growth, and uniformity. AA methods T2 and T3 were effective in separating barley cultivars into vigor categories at day four of the germination test. Computer analysis of digital images of barley seedlings is a valuable tool for testing barley seed vigor. Accelerated aging methods T2 and T3 also gave the best separation in seed lot vigor and seedling growth using the SAS index, respectively.