Plant Biotechnology

Pineapple (Ananas comosuss, var. Smooth cayenne), which is a popular tropical fruit, is propagated vegetatively. Conventional propagation alone does not provide clean and adequate planting material demanded in Ethiopia. Recently, in vitro multiplication has become a promising technique for large-scale production. However, the acclimatization to the external environment procedure impedes the efficiency, which needs carefully optimized acclimatization techniques. We report optimized acclimatization procedures following first-and second-stage hardening methods for in vitro pineapple plantlets. Primarily, Jiffy-7 peat pellet allowed growing plants vigorously and provided above 8% survival rate over soil mix. Nevertheless, in Ethiopia, soil mix is cheaper and locally accessible. The primarily acclimatized plantlets are needed to be hardened further for better establishment and survival in the field. Black polybag and polysleeve pots filled with soil mix were evaluated in the greenhouse. A significant difference was obtained between pots for number of roots and substrate weight. Polybags had higher root number than polysleeves and saved about 27% of substrates per plant, which is a reduction of 25% of total transportation cost. Hence, the soil mix and polybags were found to be preferable over substrates and pots, for subsequent in vitro pineapple acclimatization.

Pineapple (Ananas comosus L.) is one of the most potential fruit crop growing in Ethiopia due to suitable agro-ecology and economic importance. However, it is difficult to meet the demand for planting materials using the conventional propagation techniques due to production inefficiency and disease transmission. The experiment is laid in Completely Randomized Design with three treatments of vessels used along its media type, Temporary Immersion Bioreactor, TIB (RITA®, Vitropic, France) , Glass jam jar and plastic jars , replicated six times on MS medium. A highly significant difference (p<0.001) was observed between culturing vessels with the same media supplement. From this study, it was found that pineapple explants cultured on TIB having full strength MS media supplemented with 2 mgl -1 BA and 30gl –1 sucrose was found to be better which gave an average multiplication of 13.17 shoots per explant within six weeks of culture. Similarly plantlets cultured on TIB with half strengt...

Different mechanisms are tried so far to reduce the production cost of plant tissue culture through increasing multiplication rate and/or substituting expensive components for wider usage of the technology. Subsequently, replacing the most common gelling agent, agar, took an attention since higher proportion of media cost comes from it. Up to now different alternatives were tried though they have drawbacks due to their inherent chemical characteristics. Therefore the search for new alternatives like Enset ventricosum is important. Enset flour, 'Bulla', has been tried in this study for the first time to substitute agar and showed no significant difference for shoots number, root number, shoot height, leaf number and an associated fresh weight of the plantlets besides good gelling ability than Agar. Subsequently, 'Bulla' at 80g L -1 gelled well and gave 11.8 shoots with 0.95g and 13.33 roots having 1.37 cm length. This rate can also save up to 76 % cost of gelling thou...

Aloe vera Linn., plant belongs to Liliaceae family, is a plant originated in the warm, dry climates of Africa readily adaptable and grows worldwide. Slow propagation rate of axillary shoots and male sterility to use its seeds hinders its efficient propagation. Hence, the present study aimed to standardize optimum in vitro propagation conditions for it. Based on this purpose MS media supplemented with 0.6 mg/L BAP and 0.2 mg/L of IBA; 1.0 mg/L BAP; and devoid of hormone were selected as the optimum medium for Aloe vera establishment, multiplication and rooting respectively. The higher mean number of shoots, 2.90 and multiplication factor, 2.87 were registered on MS media with 0.2 mg/L IBA & 1.0 mg/L BAP respectively. During their rooting and acclimatization, the selected treatment yields 100% rooted plant and 92.59 survival percentage during acclimatization on 3:1 mixture of filter cake and sand after their fifth week. Application of this protocol helps to propagate thousands of Aloe vera plants from few initial mother plants in year period.

Sorghum [Sorghum bicolor (L.) Moench], is believed to be originated in Ethiopia and Sudan. Although, many morphological and molecular diversity studies reveal the existence of genetic variations with sorghum populations, their distribution within basic races were not considered. Hence, the present study aimed to analyze the extent and distribution of genetic variation within basic Ethiopian sorghum landraces using SSR markers. A total of 107 landraces obtained from Ethiopian Biodiversity Institute (EBI) representing 12 ecological zones grouped according to their race types based on inflorescence and spiklet on field at their maturity time. Twelve SSR markers revealed a total of 110 alleles with average polymorphic content of 0.76 and the allele frequencies show 42 of them were rare (less than 0.05), 22 ranged from 0.05 to 0.1, while 46 of them were higher than 0.1. Expected and observed heterozygosity were 0.78 and 0.2, respectively. The genetic differentiation between populations were also moderate (FST=0.07 for races and 0.13 for E/zones) indicating continuous exchange of genes among them. Partitioning the total genetic variation also indicated 61.38 and 55.17% of the variations were among individuals within racial and zonal populations, respectively. Neighbor-Joining cluster analysis also indicated four major grouping of the landraces according to their racial groups where majority of race caudatum and durra form separate groups while intermediate durra-bicolor form two separate subclusters. Overall locus, the intra-racial population diversity showed the greatest genetic diversity (He=0.77 and 0.75) among race dura-bicolor and caudatum, respectively. Information with sorghum races along their important agronomic traits could be used for conservation and future breeding programs of sorghum.

Banana and plantain are monocotyledonous herbs in the genus Musa (Musa spp.) and grown globally due to their diverse uses as export income, food and fiber. Banana is also grown widely in Ethiopia; however, the crop attracted very limited research attention and has little genetic information available. Therefore, the main objective of this study was to assess the genetic diversity and population structure of banana genotypes using 14 SSR markers. The genetic diversity of 96 banana genotypes obtained from Melkasa Agricultural Research center was analyzed using 14 SSR markers. A total of 187 alleles were identified, and the number of alleles per marker (Na) ranged from 6 to 21 with an average of 13.36. The range of polymorphic information content per marker was 0.52 to 0.93, with an average of 0.82. The results of phylogenetic analysis, principal coordinate analysis, and structure analysis showed an admixture of the populations indicating that the genotype grouping pattern did not exactly correspond to the genotypes' breeding history and genome composition. However, Clusters I to III from the phylogenetic analysis and K=3 from the population structure analysis confirmed the existence of 3 major groups among the genotypes as a whole. Analysis of molecular variance (AMOVA) revealed the presence of higher genetic variation within the population than between the population. Generally, genetic diversity and population structure obtained from this study provide inputs for the improvement of the crop.

Sorghum [Sorghum bicolor (L.) Moench], a cereal crop of family Poaceae, is believed to be originated in Ethiopia and Sudan. It is an important food security crop mainly in semi arid and tropical parts of the African countries. Although many morphological and molecular diversity studies reveal the existence of genetic variations with sorghum populations, their distribution within basic races were not considered. Hence, the present study aimed to analyze the extent and distribution of genetic variation within basic Ethiopian sorghum landraces using SSR markers. A total of 107 landraces obtained from Ethiopian Biodiversity Institute (EBI) representing 12 ecological zones grouped according to their race types based on inflorescence and spiklet on field at their maturity time. Twelve SSR markers revealed a total of 110 alleles with average polymorphic content of 0.76 and the allele frequencies shows 42 of alleles were rare (less than 0.05), 22 ranged from 0.05 to 0.1, while 46 of them were higher than 0.1. Expected and observed heterozygosity were 0.78 and 0.2 respectively. The genetic differentiation between populations were also moderate (FST=0.07 for races and 0.13 for E/zones) indicating continuous exchange of genes among them. Partitioning the total genetic variation also indicated 61.38% and 55.17% of the variations were among individuals within racial and zonal populations respectively. Neighbor-Joining cluster analysis also indicated four major grouping of the landraces according to their racial groups where majority of race caudatum and durra form separate groups while intermediate durra-bicolor form two separate sub-clusters. Overall locus the intra-racial population diversity showed the greatest genetic diversity (He=0.77 and 0.75) among race bicolor and caudatum respectively. Information with sorghum races along their important agronomic traits could be used for conservation and future breeding programs of sorghum.

Biogas is an alternative sources of energy that produced by bacteria spp particularly methanogenic through the bio-degradation of organic material under anaerobic conditions. The main objective this study was biogas production from co-digestion of goat manure and watermelon peels under anaerobic digestion and although to analyze different physicochemical parameters of substrates. Biodigestes; The 1 st Biodigester (A) contain, 100% GM and 0% WP, the 2 nd Biodigester(B) contain 70% GM and 30% WP, the 3 rd Biodigester(C) contain 50% GM and 50% WP, the 4 th Biodigester(D) contain 30% GM and 70% WP and the last 5 th Biodigester(E) contain 0% GM and 100% WP. The experiment was done in mesophilic condition (38ºc) using batch fermentation type from microbiology and central laboratories of Haramaya University. All physico-chemical parameters were measured and the result shows in each substrate there was significantly varied between previous to and after digestion. The gas production was measured started from first day of the fermentation and stop until it stop any more gas production using water displacement method for 30 days of retention time in the Biodigester. Since, the rate of biogas production was started in the third day of the experimental observation in all Biodigester and becomes 0 ml after 23 day of the retention time.