In cucumbers, heart-shaped leaves (hl) are recessive to normal leaves (Hl), and having numerous fruit spines (ns) is recessive to having few fruit spines (Ns). The genes for leaf shape and number of spines are located on the same chromosome; mapping experiments indicate that they are 32.6 map units apart. A cucumber plant having heart-shaped leaves and numerous spines is crossed with a plant that is homozygous for normal leaves and few spines. The F1 are crossed with plants that have heart-shaped leaves and numerous spines.
a. Write the genotypes of the parental (P), F1 and F2 generations. Write the genotypes showing each chromosome, separated by a backslash (/).
b. What phenotypes and proportions are expected in the progeny of this cross?