The Fertile Families - and Beyond

 

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.  

Type Description Functional Gametes

AA

Diploid Aril A
AAA Triploid Aril A & AA
AAAA Tetraploid Aril AA
AB Diploid Arilbred A & B
AAB Triploid Arilbred A & AB
ABB Triploid Arilbred AB & B
AAAB Tetraploid Arilbred AA and AB
AABB Amphidiploid Arilbred AB
ABBB Tetraploid Arilbred AB & BB
BB Diploid Bearded B
BBB Triploid Bearded B & BB
BBBB Tetraploid Bearded BB

 

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.

AA

AAA

AAAA

AB

AAB

ABB

AAAB

AABB

ABBB

BB

BBB

BBBB

AA

AA

AA AAA

AAA

AA AB

AA AAB

AB AAB

AAA AAB

AAB

AAB ABB

AB

AB ABB

ABB

AAA

AA AAA

AA AAA AAAA

AAA AAAA

AA AAA AAB AAB

AA AAA AB AAAB

AB AAB AAAB 

AAA AAAA AAB AAAB

 AAB AAAB

 AAB ABB AAAB AABB

 AB AAB

AB ABB AAB AABB

ABB AABB

AAAA

AAA

AAA AAAA

AAAA

AAA AAB

AAA AAAB

AAB AAAB

AAAA AAAB

AAAB

AAAB AABB

AAB

AAB AABB

AABB

AB

AA AB

AA AAA AB AAB

AAA AAB

AA AB BB

AA AAB AB ABB

AB AAB BB ABB

AAA AAB ABB

AAB ABB

AAB ABB BBB

AB BB

AB ABB  BB BBB

ABB BBB

AAB

AA AAB

AA AAA AAB AAAB

AAA AAAB

AA AAB AB ABB

AA AAB AABB

AB AAB ABB

AAA AAB AABB AAAB

AAB AABB

AAB ABB ABBB AABB

AB

AB ABB ABBB

ABB ABBB

ABB

AB AAB

AB AAB AAAB 

AAB AAAB

AB AAB BB ABB

AB AAB ABB AABB 

BB ABB AABB

AAB ABB AABB AAAB

ABB AABB

ABB AABB ABBB BBB

ABB BB

BB BBB ABB ABBB

 BBB ABB

AAAB

AAA AAB

AAA AAB AAAA AAAB

AAAA AAAB

AAA AAB ABB  

AAA AAB AABB AAAB

AAB ABB AABB AAAB

AAAA AAAB AABB

AAAB AABB

AAAB AABB ABBB 

AAB ABB

ABB ABBB ABB ABBB

AABB ABBB

AABB

AAB

AAB AAAB

AAAB

AAB ABB

AAB AABB

ABB AABB

AAAB AABB

AABB

ABBB AABB

ABB

ABB ABBB

ABBB

ABBB

AAB ABB

AAB ABB AAAB AABB

AAAB AABB

AAB ABB BBB

AAB ABB ABBB AABB

ABB AABB ABBB BBB

AAAB AABB ABBB

ABBB AABB

BBBB ABBB AABB

ABB BBB

ABB ABBB BBB BBBB