1. A review of the cytology of the Sorgheae (excluding
Sorghum) is presented. Chromosome behavior at meiosis is discussed whenever available.
2. An artificial key is given for the eight genera. All but two have been studied cytologically and these are both monotypic. One is the primitive
Lasiorrhachis and the other the very specialized
Asthenochloa.
3. Of the eighteen species reported, seven are studied meiotically for the first time.
4. Five is concluded to be the most likely basic chromosome number for the subtribe, but one species (
Cleistachne sorghoides) is 2
n=36 and is considered to have a basic number of nine.
5. Although polyploidy is common it seems to be less frequent than in other subtribes.
6. Noticable differences in chromosome size are seen in different genera and subgenera but their relationship to phylogeny is not certain.
7. A discussion of the phylogenetic patterns of the subtribe is presented. In general these patterns are rather direct with what appears to be two distinct lines of development. However, there are several suggestions of interconnections between these lines that need additional study.
8. It is suggested that the time is ripe for detailed hybridization studies between species within the different genera, between the subgenera in
Sorghum, between selected genera, and in a few cases between subtribes.
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