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In respect to breeding problems in Hannover the
transference of the cleistogamy and self fertility from the
wild to the cultivated species by crossing and backcrosses
became successful. In the middle of the Fig.
2 a derivative of this cross is represented ; the empty
anthers of which are pushed out from the flowers by the
developing grains (KUCKUCK und PETERS 1967 and 1970).
Tetraploid derivatives induced by colchicine treatment
proved to be semidwarfs of about 80-100 cm with very long
dense ears. They are fully self fertile and cleistogamous
(KUCKUCK unpublished).
As regards to resistance studies WATSON stated that S.
vavilovii is fully susceptible to all strains of
Puccinia graminis secalis and tritici
(information through correspondence). This result was
very well received by the scientists dealing with resistance
studies.
Recently cytoplasmatic male sterile types were found by
GEIGER (1971) in a so-called macropopulation II of primitive
"weed" rye growing in wheat fields. This macropopulation II
covers the area Marand-Koy-Maku in Asarbaidshan (Table
5). After the rye populations had been screened by my
student KRANZ (1957) some populations which seemed to be
more or less identical as to their gene pool were bulked
(=combined) in order to facilitate the preservation.
To conclude it is to be noted that it takes several years of
screening and investigations in order to find out which
collected material might be considered to be useful and
valuable for breeding programmes or research purposes in the
related fields. As to the utilization of collected material
in plant breeding programmes of other countries one should
not rely too much on ecological analogies and should not
spent too much time and energy in order to collect the
necessary data for these analogies. Screening on a large
scale through international cooperation should be given
preference.
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