Growth responses of 21-day-old ‘Pathumthani1’ rice seedlings to 1% (v/v) lactic acid alone or containing the indicated
types of chitosan at 20 or 40 mg/L, as determined by the (A) plant height, (B) shoot fresh weight, (C) shoot dry weight, (D) root length, (E) root fresh weight and (F) root dry weight. Data are shown as the mean±1 SD and are derived from 4 independent repeats. Means with a different superscript letter are significantly different (p