The
concept of a Fertile Family, members of which produce more members of the
same family when intercrossed, has been used by hybridizers for decades to
describe the more intricate workings of wide crosses.
Most hybridizers work with just one fertile family (like the TBs).
Aril/arilbred hybridizers, however, have three families available (diploid arils, tetraploid arils,
and amphidiploidlike arilbreds).
While each affords ample
opportunity for traditional line-breeding, collectively they are a
tempting realm to explore.
In its
most precise form, a separate symbol is used for each aril species.
The more general version, however, recognizes only aril and bearded
chromosome sets and makes no distinctions among the many different types
in each group. This simplifies to only 12 types involved in
producing arils and arilbreds.
In
the following chart, "A" stands for one set of aril chromosomes
and "B" stands for one set of bearded chromosomes.
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That
may still seem like a lot, but when these crosses are charted they sort
themselves out quite neatly into manageable categories.
In
the chart below,
the parental types are shown as both row and column labels.
If you pick a column corresponding to one type and a row
corresponding to the other, the cell where they intersect gives the
results of that cross – the possibilities,
not the expected ratios. Fertile
families are shown in light green and the relatively infertile
intermediate types in yellow. Other
color codes are explained in the categorical descriptions below the chart.
Clickable links lead to the corresponding Photo Gallery.
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