Sorghum verticilliflorum (Wild sorghum)

Dry seeds of S. purpureo-sericeum were irradiated with either X-rays or thermo-neutrons with three exposures each. No difference was shown in germination between the irradiated treatments and the control. The percentage of survival was greatly reduced to 2.2% in seeds treated with X-rays. However, there was no significant difference in survival between the thermo-neutron treatments and the control. Both radiation treatments inhibited seedling height to a considerable degree, and the variability of seedling height increased with higher exposures of irradiation. The types and the frequency of induced interchanges were proportional to the exposure of thermo-neutron irradiations.Twenty six translocation heterozygous plants were analyzed and considered to be semisterile plants. Spore quartet analysis revealed that the two types of adjacent segregations occur with nearly the same frequency.Six plants with pseudo-isochromosomes were detected. Pseudo-isochromosomes were often delayed in anaphase movement. They were excluded from daughter nuclei at telophase stages and eventually became micronuclei in the spore quartets.Two plants with a ring-of-six, and one plant with two pseudo-isochromosomes plus a ring-of-six were also found among the materials irradiated with high exposures of thermo-neutrons. Pollen counts showed that they had the lowest fertility among translocation heterozygous plants and no seed was obtained.

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Wild sorghum from different eco-geographic regions of Kenya display a mixed mating system

Theoretical and Applied Genetics ◽

10.1007/s00122-011-1560-5 ◽

2011 ◽

Vol 122 (8) ◽

pp. 1631-1639 ◽

Cited By ~ 14

Author(s):

Moses M. Muraya ◽

Evans Mutegi ◽

Hartwig H. Geiger ◽

Santie M. de Villiers ◽

Fabrice Sagnard ◽

...

Keyword(s):

Mating System ◽

Mixed Mating ◽

Wild Sorghum ◽

Mixed Mating System ◽

Geographic Regions

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Assessment of recent bottlenecks and estimation of effective population size in the Ethiopian wild sorghum using simple sequence repeat allele diversity and mutation models

Plant Genetic Resources ◽

10.1017/s1479262115000015 ◽

2015 ◽

Vol 13 (3) ◽

pp. 274-281 ◽

Cited By ~ 4

Author(s):

Asfaw Adugna ◽

Endashaw Bekele

Keyword(s):

Population Size ◽

Effective Population Size ◽

Simple Sequence Repeat ◽

Wild Relatives ◽

Sequence Repeat ◽

Wild Sorghum ◽

Effective Population ◽

Mode Shift ◽

Heterozygosity Excess ◽

Simple Sequence

Since the immediate wild relatives ofSorghum bicolor(L.) Moench are indigenous to Ethiopia, studying their population biology is timely for undertaking conservation measures. A study was conducted to investigate the occurrence of population bottlenecks and to estimate the long-term effective population size (Ne) in wild relatives of sorghum. For this, 40 samples of wild sorghum were collected from two remotely located populations that were allopatric to the cultivated sorghum. The presence of bottlenecks was investigated using heterozygosity excess/deficiency, mode shift and allelic diversity based on nine polymorphic simple sequence repeat (SSR) loci. We also estimated theNeof the studied populations using two different methods employing SSR mutation models. The expected heterozygosity was found to be 0.41 and 0.71 and allelic richness was 3.0 and 4.9, in Awash and Gibe populations, respectively. Neither the heterozygosity excess nor the mode-shift methods detected signatures of bottlenecks in the studied populations. The effective size of the two wild sorghum populations studied also showed no risk of population reduction in these regions of Ethiopia. Therefore, these allopatric wild sorghum populations can survive by occupying patches by the roadsides and fences, areas within abandoned farm lands, forests, etc., which shows that their wild characteristics of adaptation have been adequate for them to survive from extinction despite extensive deforestation of their habitat for modern agriculture and frequent grazing by livestock. However, this does not guarantee the survival of these species for the future andex situconservation measures or policies could help maintain their diversity.

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Seed shattering in a wild sorghum is conferred by a locus unrelated to domestication

Proceedings of the National Academy of Sciences ◽

10.1073/pnas.1305213110 ◽

2013 ◽

Vol 110 (39) ◽

pp. 15824-15829 ◽

Cited By ~ 33

Author(s):

H. Tang ◽

H. E. Cuevas ◽

S. Das ◽

U. U. Sezen ◽

C. Zhou ◽

...

Keyword(s):

Wild Sorghum ◽

Seed Shattering

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Geographical patterns of phenotypic diversity and structure of Kenyan wild sorghum populations (Sorghum spp.) as an aid to germplasm collection and conservation strategy

Plant Genetic Resources ◽

10.1017/s1479262110000225 ◽

2010 ◽

Vol 8 (3) ◽

pp. 217-224 ◽

Cited By ~ 3

Author(s):

Moses M. Muraya ◽

Hartwig H. Geiger ◽

Evans Mutegi ◽

Ben M. Kanyenji ◽

Fabrice Sagnard ◽

...

Keyword(s):

Phenotypic Diversity ◽

Diversity Index ◽

Flag Leaf ◽

Germplasm Collection ◽

Principal Component ◽

Conservation Strategy ◽

Ex Situ ◽

Regional Differentiation ◽

Wild Sorghum ◽

Geographical Patterns

Kenya lies within sorghum centre of diversity. However, information on the relative extent of diversity patterns within and among genetically defined groups of distinct ecosystems is lacking. The objective was to assess the structure and phenotypic diversity of wild sorghum populations across a range of geographical and ecological conditions in the country. Sixty-two wild sorghum populations (30 individuals per population) sampled from four distinct sorghum growing regions of Kenya and covering different agroecologies were characterized for ten qualitative traits. Plant height, number of tillers, panicle sizes and flag leaf dimensions were also recorded. Frequencies of the phenotypic classes of each character were calculated. The Shannon diversity index (H′) was used to estimate the magnitude of diversity. Principal component analysis was used to differentiate populations within and between regions. Wild sorghum is widely distributed in Kenya, occurring in sympatric ranges with cultivated sorghum, and both have overlapping flowering windows. All characters considered displayed great phenotypic diversity. Pooled over characters within regions, the mean H′ ranged between 0.60 and 0.93 in Western and Coast regions, respectively. Wild sorghum was found to show a weak regional differentiation, probably reflecting the importance of seed-mediated gene flow in shaping the wild sorghum population structure. Trait distribution was variable among regions, but there was no conspicuous distribution of the traits studied in any given region. Spontaneous hybridization and introgression of genes from cultivated to wild sorghum seems to be likely, and may already have occurred for a long time, although undocumented. Implications for in situ and ex situ genetic resources conservation are discussed.

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