Affects PSII reaction; green seedling. Green seedling, fluorescence induction kinetics class IX, 90% reduced plastoquinone (Miles 1980); reduced in photosystem II electron transport (Miles 1980, 1982), resistant to diquat (Miles 1975). TB-6Sa uncovers (Miles et al. 1985). Viability: seedling lethal at 3- to 4-leaf stage. (Polacco). Genetic 2005 6 coordinates determined from these recombination and map data: hcf5 TB-6Sa; see MaizeGDB ID:104698. This gene was originally curated in MaizeGDB Database and the map position was displayed on the maize bins map if feasible.