A recessive single gene mutant, 7B-1, in @entity523 was originally selected for its photoperiod-dependent male sterility. The 7B-1 mutant also has some pleiotropic effects including reduced light-induced inhibition, i.e. de-etiolation, of the hypocotyl in long days (LD), increased seed size and weight, and reduced transpiration rate. These traits led us to investigate the sensitivity of 7B-1 to exogenous hormones and the interaction of these responses with daylength. In LD, but not in short days (SD), 7B-1 was more sensitive than wild-type (WT) to exogenous @entity2271 ( @entity2272 ) for inhibition of seed germination, root elongation and transpiration rate. 7B-1 mutant also exhibited reduced responses to exogenous @entity15150 (GA(3)) for hypocotyl elongation, and to inhibitors of GA biosynthesis for seed germination and root and hypocotyl elongation. 7B-1 hypocotyls contained a higher level of endogenous @entity2272 than WT in both photoperiods, although @entity2272 levels were higher in LD than in SD. In contrast, growth-active GAs, i.e. GA(1), GA(3) and GA(4), and IAA were low in the mutant hypocotyls. The 7B-1 mutant appears to be an @entity2272 -overproducer, and the photoperiod-regulated @entity2272 levels may be responsible for the @entity56 of the mutant to exogenous @entity2272 .

Reduced de-etiolation of hypocotyl growth in a XXXX mutant is associated with @entity56 to, and high endogenous levels of, @entity2271 .

@entity2272 :: ('CHEBI:2365', 'Chemical') :: ['ABA'] @entity2271 :: ('MESH:D000040', 'Chemical') :: ['abscisic acid'] @entity523 :: ('4081', 'Species') :: ['tomato'] @entity15150 :: ('CHEBI:28833', 'Chemical') :: ['gibberellin'] @entity56 :: ('MESH:D004342', 'Disease') :: ['hypersensitivity']
@entity523 :: (4081,Species) :: ['tomato']
