Genus Sorghum Research Articles

Evaluation of new sorghum varieties for grain production cultivated in mineral soil

Sorghum bicolor L. (Sorghum) has been recognized as the fifth largest cereal crop in the world, following maize, wheat, rice, and barley, with a mean annual production of more than 5.89 million tons over the past five years. Grain sorghum is one of the cultivated varieties of the sorghum genus. It is primarily used as human food and animal feed due to the beneficial effects of bioactive compounds in the grain. Sorghum is less popular and unrecognizable in Malaysia, as it was not included in the reports by the Agriculture Department regarding plantation areas. In Malaysia, sorghum is limited because this crop is considered new, and no studies were conducted on the adaptability of its varieties to Malaysian soil and local climatic conditions. Crop production practices such as variety selection, planting density and fertilization will affect yield production. Therefore, a study on grain sorghum varieties (Brachy Sorgho, Jumbo Super, India and Pacific Seed 99) was conducted to evaluate the growth and yield performance of sorghum. Jumbo Super had a significantly higher value for plant height, followed by Brachy Sorgho, India and Pacific Seed 99. India showed the highest value of leaf fresh and dry weight, but no significant difference compared with Brachy Sorgho. Brachy Sorgho recorded the highest value of stem fresh and dry weight, while the least was recorded for Pacific Seed 99. Brachy Sorgho and India showed significantly higher grain yields than Jumbo Super and Pacific Seed 99 in terms of panicle length, panicle weight without grain, grain weight without panicle per plant, number of grains per panicle, and 100-grain weight. The highest gross weight of grain sorghum is Brachy Sorgho (140.00 g/plant), which showed no significant difference compared to the India variety (131.13 g/plant). Meanwhile, Jumbo Super and Pacific Seed 99 varieties showed the lowest grain weight, 77.27 g/plant and 80.16 g/plant, respectively. Overall, all four varieties are adaptable in mineral soil and are considered potential alternative crops for grain production. Bachy Sorgho and India varieties showed the best performance on grain yield compared to Jumbo Super and Pacific Seed 99 varieties. Thus, Brachy Sorgho and India varieties can be recommended for future grain production in mineral soil.

The geographic distributions and complex genetic relationships among four Sorghum taxa identified in Taiwan

AbstractThe genus Sorghum consists of 25 species, including Sorghum bicolor (L.) Moench, one of the top five cereal crops cultivated globally, and S. halepense, one of the most noxious weeds. Weedy Sorghum possesses outstanding adaptability and drought tolerance thrives in diverse environments and becomes an invasive plant worldwide. Taiwan is a unique place possessing suitable habitats for four Sorghum taxa, S. bicolor ssp. bicolor, var. technicum, ssp. verticilliflorum and S. halepense, which were identified by key morphological features. The four Sorghum taxa showed distinct geographic distributions, revealing that invasiveness was influenced by their own characteristics and human activities. The sporadic distributions of cultivated S. bicolor ssp. bicolor and var. technicum may be attributed to human disturbance and agricultural activities. The rhizomatous S. halepense was widely distributed and showed the highest genetic diversity (He > 0.776) among the four taxa, with its strong adaptation to various environments threatening the agricultural practices and ecosystem in Taiwan. In contrast, the newly naturalised S. bicolor ssp. verticilliflorum was confined to and dominant in southern Taiwan, with the lowest genetic diversity (He < 0.272). Significant genetic differentiation (FST = 0.5207) between the two ssp. verticilliflorum subpopulations was associated with natural geographic isolation. This study concretely elucidated the geographic distributions, genetic diversity and relatedness of invasive and escaped Sorghum taxa, indicating the potential aggressiveness and hazard of weedy Sorghum in Taiwan.

VIRULENCE OF PSEUDOMONAS SYRINGAE STRAINS FROM SORIZ (SORGHUM ORYSOIDUM) AND THEIR SPECIALIZATION

Objective. To study the virulence properties of Pseudomonas syringae strains isolated from soriz and various representatives of sorghum crops in Ukraine and to establish the sensitivity range of plants to these pathogens. Methods. Ten strains freshly isolated from soriz (Sorghum orysoidum) were used to study virulence properties, namely: Pseudomonas syringae 210342, 211141a, 211141, 210341, 21034, 210541b, 210541, and Pseudomonas sp. 210521, 21052, 21054, pathogenic strains of sorghum crops from the collection of the Department of Phytopathogenic Bacteria of D. K. Zabolotny Institute of Microbiology and Virology of the National Academy of Sciences of Ukraine and collection strains of phytopathogens that can be potential causative agents of bacterial diseases of soriz or are causative agents of diseases of agricultural crops that can be used in crop rotation. The virulence properties of strains isolated from sorghum were determined on plants of the genus Sorghum. To establish the range of crops sensitive to these pathogens, a number of plants belonging to other genera and families, both cultivated and weed, were tested. Artificial inoculation was carried out in the greenhouse and in the field as injection of bacterial suspension of 1×109 CFU/mL into the leaf surface and stem at all phases of the development of soriz and sorghum cultures. Accounting for artificial contamination was carried out in 7 to 14 days using a locally modified 6-point scale. Aggressiveness of bacteria was assessed by the size of necrosis that formed at the site of injection of the bacterial suspension. Aggressiveness was calculated as the arithmetic mean of the results. Results. P. syringae strains isolated from soriz were found to be virulent for soriz and sorghum crops, however, heterogeneous in aggressiveness. The most aggressive strains were P. syringae 211141a, 210341, and 21034. Some collection strains, isolated from different cultures, showed higher aggressiveness against sugar and grain sorghum than against soriz and Sudan grass. The studied strains of phytopathogens were found to affect segetal vegetation; the most sensitive to the studied strains were horsetail, field bindweed, goldenrod. They showed high aggressiveness against setaria, ragweed, and common sedge. Strains of P. syringae affecting potato, beet, sunflower and tomato plants were identified. Conclusion. Pseudomonas syringae strains isolated from contaminated sorghum plants are virulent and capable of infecting a wide range of plants, including plants of the sorghum family, other types of agricultural crops, and various types of segetal vegetation. Strains of Pectobacterium carotovorum, Xanthomonas vasicola pv. holcicola, Diskeya chryzanthemy, Pantoea agglomerans can be potential pathogens of sorghum crops. The results indicate that segetal vegetation can serve as a reservoir of bacterial infections and play a role in the transfer of bacterial pathogens.

The use the VIR world collection in the selection of new varieties and hybrids of sugar sorghum for arid regions of the Russian Federation

Relevance . Currently, a highly productive agricultural crop, unique in drought resistance, sugar sorghum is traditionally used in the crop industry of the agro-industrial complex mainly for fodder purposes for the production of hay, silage, haylage, monofeed, briquettes from biomass, and in recent years the direction related to technical and food processing has been developing. Breeders are widely attracted to the source material from the world collection of VIR, on the basis of which new highly productive varieties and hybrids are created, characterized by a high sugar content in the juice of stems, as well as maturing in the conditions of the cultivation region. The multidirectional selection of new varieties of sugar sorghum with specified economic characteristics is relevant for providing raw materials for various branches of the agro-industrial complex. Methods . The field assessment of morphometric indicators, the yield of biomass and seeds of the studied samples was carried out according to the Methodology of the state variety testing of agricultural crops, as well as according to the Broad unified classifier of cultivated species of the genus Sorghum bicolor (L.) Moench. Results . The study of the gene pool of sugar sorghum made it possible to identify 18 samples that are donors of economically valuable traits, which are included in the working collection for the creation of new forms. Some samples are donors of several economically valuable signs: 6 signs — Volonter, 5 signs — Scheherezada, k-302, L-39/12; 4 signs — Izolda, Sahara, Seviliay, k-256, k-257, k-10092, L-66/13, L-67/13; 3 signs — Moment, Chaika, k-327, L-44/13. According to the developed model of the variety and the results of the tests, a new variety of sugar sorghum Izolda was isolated, surpassing the zoned variety Volzhskoe 51 in biomass yield by 21,0% and in seeds yield — by 11,1% in the conditions of 2020–2021.

Bioenergy routes for valorizing constructed wetland vegetation: An overview

Valorizing constructed wetlands vegetation into biofuels can be a way to contribute to mitigating the increasing energy demand, avoiding the use of arable land, freshwater, and fertilizers consumption, while simultaneously treating wastewater with eco-friendly technology. This work shortly overviews the main genera of wetland plants and the main routes of vegetal biomass conversion into biofuels including biochemical and thermochemical processes, and through a cross-search, in the Scopus database, the research intensity in bioenergy application for each genus was assessed. A total of 283 genera of wetland plants were identified and classified into five groups, from very common to very rare genera. The very common group includes 10 genera and contributes to 62% of the literature hits, while the 147 genera classified as very rare contribute to only 3% of the hits. Concerning the bioenergy applications, four genera stand out from the remaining. The plants of the genus Sorghum are the most referred to in bioenergy applications, followed by the genera Brassica, Miscanthus, and Saccharum. Miscanthus is a less common wetland plant, while the other genera are rarely applied in constructed wetlands. The relevance of bioenergy routes depends on the plants' group. For common wetland plants, the most relevant applications are biogas production, followed by bio-ethanol production, and pyrolysis processing. As a recommendation for future research works the genera with high energy potential should be evaluated as wetland vegetation, and it is recommended that the goal to recover wetland vegetation for bioenergy applications be viewed as an integral step of the design and implementation of constructed wetlands facilities.

Variant analysis of grain size related genes in the genus Sorghum

Grain size and weight are two of the most important determinants of crop yield. Key genes associated with the grain size and weight have been identified in major crops. However, studies on the genetic basis of the grain size and weight related genes in wild Sorghum are limited. In this study, we analysed the variation of grain size related genes using variant analysis of 15 accessions across one cultivated and six tertiary gene pool species representing the five subgenera of Sorghum. A wide variation in grain size related parameters was observed. The highest grain weight, width, and thickness was observed for the accession S. bicolor (L.) Moench 314,746, while the highest grain length was observed for the accession S. macrospermum E.D. Garber 302,367. The wild sorghum species exhibited high morphological diversity. The six candidate genes related to grain size, Sobic.001G335800 (qGW7/GL7), Sobic.001G341700 (GS3), Sobic.002G257900 (GW8), Sobic.003G035400 (GW5/qSW5), Sobic.004G107300 (GW2), and Sobic.009G053600 (GS5) showed polymorphism in the coding sequence regions including variants generating premature stop codons. These variants might contribute to the observed variation in grain size and weight. The tertiary wild sorghum species may be a useful source of genes for understanding and engineering grain size in sorghum and other cereals.

Optimization of elements of forage sorghum cultivation in the south-west of the Central region of Russia

Relevance. In the agro-climatic conditions of the southwestern part of the Central region of Russia, studies have been conducted aimed at improving the zonal agrotechnology of forage sorghum in order to optimize individual elements of cultivation that are relevant and timely. The main task was to assess the effectiveness of mineral fertilizers and seeding rates on yield, crop structure, nutritional value of the aboveground mass of sorghum varieties and hybrids, their energy assessment in the conditions of gray forest soils of the Bryansk region.Material and methods. The experimental work was carried out in 2015–2020 at the experimental field of Bryansk GAU. The objects of research were 3 sorghum-sudan grass hybrids: Slavyanskoe pole 15 F1, Sabantuy F1, Solaris and 5 varieties of sweet sorghum: Zernogradskij yantar, Debut, Listvenit, Sazhen, Sever. Agricultural technology of experiments —adopted in the region for silage and fodder crops. The laying of experiments, field records and observations were carried out according to the Broad Unified Classifier of the CMEA, the International Classifier of the CMEA of cultivated species of the genus Sorghum Moench and the Methodology of the state variety testing of agricultural crops.Results. The significant influence of azophoska , borophosphate and ammonium nitrate on the growth, development, yield and quality of the feed massof sorghum-sudan grass hybrids has been established. The highest yield of 14.8–15.8 t dry matter or 65–71 t ofgreen mass per 1 ha formed sorghum-sudan grass hybrids Sabantuy F1 and Solaris in the variant with N90 feeding on the main background 1 — azophoska N60P60K60. High-yielding agrocenoses of sweet sorghum Listvenit were marked—, 65–70.9 t/ha of green mass with a seeding rate of 500 thousand pieces of germinating seeds per 1 ha. The highest yield of gross energy with the harvest was provided by the Listvenit variety (54.8 GJ/ha), in the Sazhen and Sever varieties in the range of 50.1–50.7 GJ/ha. A high energy coefficient of 4.3–4.5 and an energy efficiency coefficient of 2.1 and 2.4respectively were shown by crops of Listvenitand Sever varieties.

Regulation of cyanogenic glucosides in wild and domesticated Eusorghum taxa.

Domesticated sorghum (Sorghum bicolor [L.] Moench subsp. bicolor) diverts significant amounts of nitrogen away from primary metabolism to the synthesis of cyanogenic glucosides (CNglc) - specialized metabolites that release toxic hydrogen cyanide (HCN). Our aim was to identify the point in the genus Sorghum Moench at which plants gained the ability to maintain hazardous concentrations of cyanogenic glucosides in their leaves into maturity (HCN potential >0.4 mg g-1 ). This ability occurs in domesticated sorghum (in the subgenus Eusorghum), but not in wild taxa in other Sorghum subgenera. Eight accessions from the subgenus Eusorghum were grown in a common garden: an improved sorghum line, five sorghum landraces, the crop's wild progenitor (S. bicolor subsp. verticilliflorum [Steud.] de Wet ex Wiersema & J. Dahlb.) and wild Sorghum propinquum (Kunth) Hitchc. HCN potential was measured in plants (n = 80) at the three-leaf stage and at 6 weeks old. All study accessions, including the wild taxa, had hazardous CNglc concentrations in the leaves at both the three-leaf stage (mean HCN potentials > = 2.5 mg g-1 ) and at 6 weeks old (mean HCN potentials > = 0.68 mg g-1 ), greatly contrasting the much lower mature leaf HCN potentials previously found in wild Sorghum taxa outside subgenus Eusorghum (generally <= 0.01 mg g-1 ). Our results suggest that the ability to maintain hazardous leaf HCN potentials into maturity might have arisen during the divergence of Eusorghum from other Sorghum subgenera, rather than during the speciation or domestication of S. bicolor, and highlights the value of utilizing Sorghum taxa outside Eusorghum in efforts to improve the crop safety of sorghum.

Cyanogenesis in the Sorghum Genus: From Genotype to Phenotype.

Domestication has resulted in a loss of genetic diversity in our major food crops, leading to susceptibility to biotic and abiotic stresses linked with climate change. Crop wild relatives (CWR) may provide a source of novel genes potentially important for re-gaining climate resilience. Sorghum bicolor is an important cereal crop with wild relatives that are endemic to Australia. Sorghum bicolor is cyanogenic, but the cyanogenic status of wild Sorghum species is not well known. In this study, leaves of wild species endemic in Australia are screened for the presence of the cyanogenic glucoside dhurrin. The direct measurement of dhurrin content and the potential for dhurrin-derived HCN release (HCNp) showed that all the tested Australian wild species were essentially phenotypically acyanogenic. The unexpected low dhurrin content may reflect the variable and generally nutrient-poor environments in which they are growing in nature. Genome sequencing of six CWR and PCR amplification of the CYP79A1 gene from additional species showed that a high conservation of key amino acids is required for correct protein function and dhurrin synthesis, pointing to the transcriptional regulation of the cyanogenic phenotype in wild sorghum as previously shown in elite sorghum.

The complete chloroplast genome sequence and phylogenetic analysis of Sudan grass (Sorghum bicolor subsp. drummondii) cultivar Sa (Poaceae) from Anhui province, China

The complete chloroplast genome of Sorghum bicolor subsp. drummondii cultivar Sa (a modern Sudan grass cultivar) was sequenced and analyzed in the present study. The chloroplast genome is 140,754 bp in length and includes a large single-copy region 82,688 bp in length, a small single-copy region 12,503 bp, and two inverted repeat regions 22,782 bp each. The genome contains 104 unique genes, including 4 rRNAs, 29 tRNAs, and 71 protein-coding genes. The phylogenetic analysis showed that Sudan grass cultivar Sa in a clade with five other complete chloroplast genomes of S. bicolor. The work facilitates studies on population genetic structure and phylogenetic relationships in genus Sorghum.

Comparative evolution of vegetative branching in sorghum.

Tillering and secondary branching are two plastic traits with high agronomic importance, especially in terms of the ability of plants to adapt to changing environments. We describe a quantitative trait analysis of tillering and secondary branching in two novel BC1F2 populations totaling 246 genotypes derived from backcrossing two Sorghum bicolor x S. halepense F1 plants to a tetraploidized S. bicolor. A two-year, two-environment phenotypic evaluation in Bogart, GA and Salina, KS permitted us to identify major effect and environment specific QTLs. Significant correlation between tillering and secondary branching followed by discovery of overlapping sets of QTLs continue to support the developmental relationship between these two organs and suggest the possibility of pleiotropy. Comparisons with two other populations sharing S. bicolor BTx623 as a common parent but sampling the breadth of the Sorghum genus, increase confidence in QTL detected for these two plastic traits and provide insight into the evolution of morphological diversity in the Eusorghum clade. Correspondence between flowering time and vegetative branching supports other evidence in suggesting a pleiotropic effect of flowering genes. We propose a model to predict biomass weight from plant architecture related traits, quantifying contribution of each trait to biomass and providing guidance for future breeding experiments.

The Evolutionary Dynamics of Repetitive DNA and Its Impact on the Genome Diversification in the Genus Sorghum

Polyploidization is an evolutionary event leading to structural changes of the genome(s), particularly allopolyploidization, which combines different genomes of distinct species. The tetraploid species, Sorghum halepense, is assumed an allopolyploid species formed by hybridization between diploid S. bicolor and S. propinquum. The repeat profiles of S. bicolor, S. halepense, and their relatives were compared to elucidate the repeats’ role in shaping their genomes. The repeat frequencies and profiles of the three diploid accessions (S. bicolor, S. bicolor ssp. verticilliflorum, and S. bicolor var. technicum) and two tetraploid accessions (S. halepense) are similar. However, the polymorphic distribution of the subtelomeric satellites preferentially enriched in the tetraploid S. halepense indicates drastic genome rearrangements after the allopolyploidization event. Verified by CENH3 chromatin immunoprecipitation (ChIP)-sequencing and fluorescence in situ hybridization (FISH) analysis the centromeres of S. bicolor are mainly composed of the abundant satellite SorSat137 (CEN38) and diverse CRMs, Athila of Ty3_gypsy and Ty1_copia-SIRE long terminal repeat (LTR) retroelements. A similar centromere composition was found in S. halepense. The potential contribution of S. bicolor in the formation of tetraploid S. halepense is discussed.

Phylogenetic relationships in the Sorghum genus based on sequencing of the chloroplast and nuclear genes.

Sorghum [Sorghum bicolor(L.) Moench] is an important food crop with a diverse gene pool residing in its wild relatives. A total of 15 sorghum accessions from the unexploited wild gene pool of the Sorghum genus, representing the five subgenera, were sequenced, and the complete chloroplast genomes and 99 common single-copy concatenated nuclear genes were assembled. Annotation of the chloroplast genomes identified a total of 81 protein-coding genes, 38 tRNA, and four rRNA genes. The gene content and gene order among the species was identical. A total of 153 nonsynonymous amino acid changes in 40 genes were identified across the species. Phylogenetic analysis of both the whole chloroplast genome and nuclear genes revealed a similar topology with two distinct clades within the genus. The species within the subgenera Eusorghum, Chaetosorghum, and Heterosorghum clustered in one clade, whereas the species within the subgenera Parasorghum and Stiposorghum clustered in a second clade. However, the subgenera Parasorghum and Stiposorghum were not monophyletic, suggesting the need for further research to resolve the relationships within this group. The close relationship between the two monotypic subgenera Chaetosorghum and Heterosorghum suggests that species within these subgenera could be considered as one group. This analysis provides an improved understanding of the genetic relationships within the Sorghum genus and defines diversity in wild sorghum species that may be useful for crop improvement.

B Chromosomes in Genus Sorghum (Poaceae).

B chromosomes (Bs) are supernumerary dispensable genomic elements that have been reported in several thousand eukaryotic species. Since their discovery, Bs have been subjected to countless studies aiming at the clarification of their origin, composition, and influence on the carriers. Despite these efforts, we still have very limited knowledge of the processes that led to the emergence of Bs, the mechanisms of their transmission, and the effects of Bs on the hosts. In the last decade, sophisticated molecular methods, including next-generation sequencing, have provided powerful tool to help answer some of these questions, but not many species have received much attention yet. In this review, we summarize the currently available information about Bs in the genus Sorghum, which has so far been on the periphery of scientific interest. We present an overview of the occurrence and characteristics of Bs in various Sorghum species, discuss the possible mechanisms involved in their maintenance and elimination, and outline hypotheses of the origin of Bs in this genus.

Wild Sorghum as a Promising Resource for Crop Improvement.

Sorghum bicolor (L.) Moench is a multipurpose food crop which is ranked among the top five cereal crops in the world, and is used as a source of food, fodder, feed, and fuel. The genus Sorghum consists of 24 diverse species. Cultivated sorghum was derived from the wild progenitor S. bicolor subsp. verticilliflorum, which is commonly distributed in Africa. Archeological evidence has identified regions in Sudan, Ethiopia, and West Africa as centers of origin of sorghum, with evidence for more than one domestication event. The taxonomy of the genus is not fully resolved, with alternative classifications that should be resolved by further molecular analysis. Sorghum can withstand severe droughts which makes it suitable to grow in regions where other major crops cannot be grown. Wild relatives of many crops have played significant roles as genetic resources for crop improvement. Although there have been many studies of domesticated sorghum, few studies have reported on its wild relatives. In Sorghum, some species are widely distributed while others are very restricted. Of the 17 native sorghum species found in Australia, none have been cultivated. Isolation of these wild species from domesticated crops makes them a highly valuable system for studying the evolution of adaptive traits such as biotic and abiotic stress tolerance. The diversity of the genus Sorghum has probably arisen as a result of the extensive variability of the habitats over which they are distributed. The wild gene pool of sorghum may, therefore, harbor many useful genes for abiotic and biotic stress tolerance. While there are many examples of successful examples of introgression of novel alleles from the wild relatives of other species from Poaceae, such as rice, wheat, maize, and sugarcane, studies of introgression from wild sorghum are limited. An improved understanding of wild sorghums will better allow us to exploit this previously underutilized gene pool for the production of more resilient crops.

Conservation and divergence in sorgoleone production of sorghum species.

Sorgoleone-358 is an important allelochemical of the oily droplets exuded from root hairs of various species in the Sorghum genus. Due to its hydrophobic nature, sorgoleone-358 can be strongly adsorbed onto soil organic matter, resulting in increased sorgoleone soil persistence. Because of the herbicidal activity of sorgoleone on many small-seeded weeds, concerns have been raised that sorghum residues may have a detrimental effect on emergence of wheat used as a double crop in the southeastern United States. Laboratory experiments were conducted to evaluate root exudate production and its sorgoleone-358 content for 36 cultivated sorghum cultivars as well as eight shattercane [Sorghum bicolor (L.) Moench ssp. arundinaceum (Desv.) de Wet & Harlan] accessions and one johnsongrass [S. halepense (L.) Pers.] accession. Using a capillary growing mat system, root exudate was extracted with dichloromethane and subjected to chromatography analysis to determine sorgoleone-358 content. Root biomass of 7- to 12-d-old seedlings averaged 18.8mg g-1 seed, and root exudate production ranged from 0.2 and 4.8mg g-1 root fresh weight (RFW). The amount of sorgoleone produced varied greatly among sorghum accessions. Sorgoleone-358 amount in the root exudate averaged 0.5mg g-1 RFW and varied from 0.13 to 1.05mg g-1 for shattercane cultivar S7 and cultivated sorghum cultivar 992123, respectively. Regarding volume of root biomass, sorgoleone-358 levels averaged 0.49mg g-1 (range, 0.06-1.46mg g-1 ) for sorghum cultivar AAS3479 and shattercane cultivar S2, respectively. Segregation of commercial sorghum cultivars according to their maturity group did not show any difference in root biomass and dry extract production, but early-maturing cultivars produced on average 18% less sorgoleone-358 compared with medium- and late-maturing cultivars. These results suggest that sorgoleone production may be genetically constitutive because sorghum growing conditions were identical across cultivars.

Pedigree comparison highlights genetic similarities and potential industrial values of sugarcane cultivars

Cultivar pedigrees from two sugarcane origins, 9 Argentine (AR) and 7 American (AM) have been reconstructed, and their genetic similarities (based on coefficient of parentage, COP, estimates) show an average of 0.206 ± 0.054. CP clones that enter the pedigrees of AM cultivars are parents or grandparents of AR cultivars, demonstrating that these genotypes have a strong genetic lineage in common. On average, AR pedigrees are smaller and contain less number of founding species than AM pedigrees. However, the lower height of the former is not explained by the different participation of founding species in the pedigrees. The presence of founding species in AR and AM pedigrees increases with the year of cultivar selection, indicating that more founding species entered the pedigree in recently selected cultivars than in older ones. The ancestry of the 16 cultivars trace back to 3 founding species: Saccharum officinarum, S. barberi, and S. spontaneum, with S. officinarum showing the greatest percentage of participation. As S. sinensis participates in 13 pedigrees and S. robustum in 3, the 5 founding species are present in 2 out of 16 pedigrees. Interestingly, the genus Sorghum enters the pedigree of LCP 85-384 pedigree. Industrial parameters assayed indicate that AR and AM cultivars were preferentially selected for their relatively high sucrose content and sugar yield in accordance with two facts: (i) the genetic background and the sucrose genes of sugarcane hybrids provided by the 68% of participation S. officinarum clones, and (ii) no clones of high fiber S. spontaneum have entered the pedigrees in earlier generations.

Geographical distribution, diversity and gap analysis of East African sorghum collection conserved at the ICRISAT genebank

The aim of the investigation was to assess the geographical distribution, diversity and gaps in sorghum collection from East African countries conserved at the ICRISAT genebank. The collection represents a total of 12,750 accessions including 11,672 landraces, 877 breeding materials, six improved cultivars, and 195 wild accessions. Passport data and FloraMap, a GIS software were used to assess geographical distribution and identify gaps. Range, mean, variance and phenotypic diversity index were estimated using GENSTAT 13.1. to assess the diversity in the collection. Cultivated sorghums classified into races and intermediate races based on spikelet and panicle morphology differed significantly, and races showed more variation than intermediate races for days to 50% flowering in postrainy season, plant height in rainy season, basal tillers per plant, panicle length, seed width and 100 seed weight. A total of 153 districts located in 50 provinces of 10 East African countries were found as the geographical gaps. Probably due to large variation for maturity, timing of collecting mission, and accessibility to the area under sorghum cultivation, both North and South Sudan were found as the major gaps with seven and 50 districts, respectively. The wild sorghum collection from East African countries belongs to S. bicolor, S. halepense, S. lanceolatum, S. macrochaeta, S. purpureosericeum and S. versicolor. Remaining species of genus sorghum were considered as taxonomic gaps. The gaps identified in the present study need to be explored on a priority basis to collect and conserve most diverse sorghum germplasm.

Genetic Diversity of Wild Sorghum (Sorghum bicolor ssp. verticilliflorum (L.) Moench) Germplasm from Ethiopia as Revealed by ISSR Markers

Ethiopia is one of the center of origin and diversity of Sorghum bicolor (L.) Moench. The genus Sorghum has been divided into three subspecies, namely, bicolor, verticilliflorum and drummondii. The study of the genetic diversity of the wild species of sorghum significantly contributes to the improvement of Sorghum. The aim of study was to investigate the genetic diversity of wild Sorghum from Ethiopia using Inter-Simple Sequence Repeat markers (ISSR) markers. ISSR were used to estimate genetic diversity among and within 12 populations of wild sorghum that were collected from different ecological zones of Ethiopia. Seven selected ISSR primers yielded 43 reproducible bands from 96 individuals, eight individuals representing each population. Jimma 1 population exhibited highest gene diversity of 0.2885. The least gene diversity (0.1192) was observed in East Wollega 1. Shannon diversity index also showed the same diversity pattern where Jimma 1 population showed the highest value (0.4067) and the least Shannon diversity index was exhibited by East Wollega 1 population (0.1757). Analysis of molecular variance showed that within population variation was higher (54.68%) than among population variation (45.32%). Un-weighted pair group method with arithmetic mean (UPGMA) based dendrogram showed Gambella 1 and Jimma 2 populations showed highest similarity. Individual based UPGMA clustering of overall analysis showed five major clusters and some of individuals were clustered with respect to their populations except few intermixed individuals from other populations. In two dimensional (2 D) Principal coordinate analysis (PCO), most of West Wollega 1 and West Wollega 2 individuals formed their separate group except few individuals from other populations mixed with them

Correlation coefficients of morphological: Productive traits of species of Sorghum genus

Objective of the research were phenotypic and genetic correlation coefficients of three species of Sorghum genus - forage sorghum S. bicolor Moench. (genotype NS-Dzin), Sudan grass S. sudanense L. (genotype Zora) and interspecies hybrid S. bicolor x S. sudanense (genotype Siloking). Studies were carried out on samples of plant material from the first cut. The following morphological-productive traits were studied: plant height, number of leaves per plant, mass of leaves on the stem, average stem mass and yield of green biomass. In the analysis of genetic and phenotypic coefficients, differences depending on the impact on studied morphological-productive traits are observed. The highest value of the stem height was recorded in Sudan grass (2.281 m), as well as number of leaves per plants (7.917). The greatest mass of leaves per plant was established in forage sorghum (49.05 g), and the highest average stem mass was recorded in interspecies hybrid plants (80.798 g). Variation of morphological-productive indicators per species was significant and very significant. Coefficients of simple correlations indicate the presence of very strong to almost complete, statistically very significant positive correlations, so these effects were expected. Plant height and number of leaves were not directly but indirectly statistically significant to yield of green biomass and varied from insignificant and very weak to sporadically medium strong and statistically significant.