Affects PSII thylakoid membrane core complex; green seedling. Green, fluorescence induction kinetics class III, 70% reduction in photosystem II activity (Miles 1980, 1982). TB-1La uncovers (Leto and Miles 1979; Leto 1982; Miles et al. 1985). Classification by hcf trait very good. (Polacco). Genetic 2005 1 coordinates determined from these recombination and map data: TB-1La(1) hcf41; see MaizeGDB ID:104692. This gene was originally curated in MaizeGDB Database and the map position was displayed on the maize bins map if feasible.