Inheritance studies with inbred lines of maize having different activity levels of the AP 1 controlled acid phosphatase isozymes

Abstract

The genetic control of acid phosphatase-1 (AP ₁) activity in pollen of maize was studied by crossing inbred lines having different AP ₁ isozymes and different activity levels of the A P ₁ enzyme. Usually, the intensities of the SS and FF isozyme bands were not equal in pollen of A P ₁ ^S /A P ₁ ^F heterozygous F ₁ hybrids, but the relative intensities of the two bands were not correlated to the activity levels of the parental lines. The A P ₁ ^S /A P ₁ ^S and A P ₁ ^F /A P ₁ ^F F ₂ populations differed in their mean level of activity. Both populations showed segregation in the activity levels indicating single gene control. The intensity ratios of the SS and FF bands in the different heterozygous A P ₁ ^S /A P ₁ ^F F ₂ plants did not segregate. The results support the competition model for gene regulation proposed by Schwartz (1971).