DIGITAL IMAGE-ANALYSIS SYSTEM FOR DETERMINING TISSUE-BLOT IMMUNOASSAYRESULTS FOR RATOON STUNTING DISEASE OF SUGARCANE

A digital image analysis system (DIAS) was evaluated for enumerating c olonized vascular bundles (CVB) from membranes resulting from the tiss ue-blot immunoassay (TBIA) of sugarcane clones being screened for resi stance to ratoon stunting disease. Fourteen sugarcane clones were inoc ulated, transplanted to the field, grown to maturity, and sampled in a prescribed manner for TBIA. Tissue blots were developed, and immunoas sayed membranes were counted by both DIAS and the standard visual meth od. The correlation between mean CVB for clones determined by DIAS vs. visual counting was statistically significant (r = 0.90). DIAS is qui cker than visual counting and eliminates problems related to operator bias and fatigue. The number of samples evaluated during an 8-hr perio d was 1,200-1,350 using DIAS vs. 450-600 using visual counting techniq ues.