This study was carried out during three successive seasons. 2001. 2002. and
2003 at the Experimental Farm of EI-Kassasein Horticullure Research Station. The
main objective of this work was to study the performance of developmental and yield
characters of the three pea (Pisum sativum) parental genotypes and their F" F2, BC,
and Be2 also to study the type of gene action and the potymorphism in the esterase
and malate dehydrogenase molecular forms in each of root, stem. leaf and seed
tissues. The six generations, P" P2, F" F2, Bc, and BC2 were grown in 2003 season
and data were recorded on the means of all generations.
The F, "Atol X Marnoth" was higher than both parents for number of seeds per
pod, weight of seeds per pod and diameter per pod. The BC, cross "Mammoth X
Jurbo" had the higl'1est mean values (or all characters except (or stem length and
number of leaves per plant. The BC2 of the cross "Jurbo X Mammoth" had the highest
mean values (or all characters except for the stem length.
Significant values of the three scaling tests indicated the presence of non-allelic
interaction in almost all characters of the four crosses.
Both positive and negative signifiant additive gene effects were observed in most
characters ot three out of the four crosses. MeanWhile, negtive significant additive
gene eHects were observed in (our characters o( the cross "Mammoth X Alai".
The dominance gene effects were significant (or all characters over all crosses
except for number of branches in all crosses, grow1h rate and weight of seeds per pod
in the cross "Mammoth X Atcr indicating that the improvement of these characters
could be achieved through recurrent selection.
Non-allelic interactions of the types "additive X additive", "additive X dominance"
and "dominance X dominance' were found to be controlling the inheritance of most
characters in all the four crosses.
Isozyme polymorphism showed both qualitative and quantitative changes in either
isoesterase or malate dehydrogenase banding patterns. A total of twenty-two and
thirteen molecular (arms was observed (or esterase and malate dehydrogenase
isozymes, respectively.
Tissue specificity in segregated generations showed that the different molecular
forms could be assigned to ten loci and five loci for the esterase and malate
dehydrogenase isozymes. respectively.
These results indicated that both the developmental and yield characters under
study are expressed through biochemical path ways ',',;'Ich might not be affected
directly by either esterase or malate dehydrogenase.