Agriculture Reference
In-Depth Information
Fig. 1.1.
Daniel Zohary collecting wild relatives of domesticated plants. (a) Wild rye
(
Secale
) in Turkey, late 1990s. (b) Wild lettuce (
Lactuca
) in Georgia, late 1990s.
populations, (ii) the domestication of various crops and fruit trees in
view of their genetic relationships with wild relatives, and (iii) the
interface between crop evolution and human societies as shown by
archeological
findings had on the origin of
agriculture and on human evolution (Fig. 1.1).
findings and the impact these
II. GENETIC RELATIONSHIPS AMONG RELATED PLANT SPECIES
Zohary
s Ph.D. thesis with Stebbins at Berkeley dealt with the
Dactylis
glomerata
species complex, which consists of diploid and tetraploid
populations across the Mediterranean Basin and the Near East. In
locations in Israel where diploid and tetraploid plants coexisted, natural
triploid hybrids were found (Zohary and Nur 1959). Plants introduced
from wild populations were crossed to each other and their progeny
were thoroughly examined cytologically and morphologically. Many
diploid plants also contained up to three supernumerary chromosomes,
and in some populations, their frequency reached 50% (Zohary and
Ashkenazi 1958). Although
D. glomerata
(orchard grass) is an important
forage plant, Zohary
'
s interests soon shifted to Mediterranean genera
that included the most important crops associated with the rise of
agriculture, namely, wheat, barley, oats, peas, and lentils.
In the
Triticum
'
Aegilops
wheat group, Zohary andhis students (Zohary
and Feldman 1962; Feldman 1965; Pazy and Zohary 1965) investigated
genetic relationships and natural hybridization among the tetraploid
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