Abstract

The purpose of this study was to distinguish seed vigour in rice (Oryza sativa L.) through the speed of radicle emergence indices using image processing. Correlation of seed vigour levels was also analysed after evaluating using saturated salt accelerated aging (SSAA) test and image processing using visual and RiceSeedVigour® software. Nine indica rice seed samples from 5 popular cultivars in Thailand consist of Khao Dawk Mali 105, RD31, Pathum Thani 1, RD6 and Sang Yod Phattalung were tested. The standard germination test and radicle emergence speed were tested using image processing after seeds were germinated on the Top of Paper (TP technique) at 25 °C under 24 hours light. The SSAA test were performed at 42°C for 72 hours, germination then seeds were tested by Between Paper (BP) technique at 25 °C keep the lights on all the time. Results reveal that use of radicle emergence speed i.e. mean radicle emergence time (2 mm in length), could distinguish seed vigour into 4 groups and this method spend 140 hours to finish the process. Contrast to results of SSAA test, 400 hours method, this technique distinguished seed vigour levels of rice into 6 groups. The negative correlations between SSAA test and mean radicle emergence time using visually and RiceSeedVigour® were found. The coefficient of determination (R²) of SSAA test and visual and RiceSeedVigour® was equal -0.54.