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To assess broad sense heritability and phenotypic and genetic correlations among sugarcane yield components, an experiment was conducted at Wonji and Metehara Sugar Estates of Sugar Corporation of Ethiopia during 2012/2013. High broad sense heritability (h 2 ) was detected for stalk diameter (0.730), single cane weight (0.672), millable cane number (0.624), stalk height (0.624) and pol % (0.608), indicating that these traits could be selected for easily. Expected genetic gain of the yield components was moderate to high. All traits had low to high genetic correlations (rg = −0.005 to 0.884) with cane yield and (rg = 0.027 to 0.999) with sugar yield. On average genetic correlations were higher than phenotypic correlations. High Genotypic Coefficient of Variation (GCV), broad sense heritability and expected genetic advance were recorded for stalk diameter, single cane weight and millable cane number. A selection strategy based on these traits could lead to improvement in cane and sugar yield.

To study the relations of certain morphological and sugar quality characters with sugarcane yield, an experiment was conducted at Wonji and Metehara Sugar Estates, Ethiopia between March 2012 and October 2013. The experiment, comprising of 400 sugarcane genotypes of which 174 were local that were collected from different regional states of Ethiopia and 226 introduced, was laid out in partial balanced lattice design with two replications. Data was collected on cane yield and its components, sugar yield and sugar quality traits. ANOVA, correlation and path coefficient analysis were done. Analysis of variance revealed significant differences (P < 0.01) for all the characters studied. Cane yield showed strong positive and highly significant (P < 0.01) correlation with millable cane number (r = 0.832), single cane weight (r = 0.528), stalk height (r = 0.517) and sugar yield (r = 0.987). There was also positive significant (P = 0.05) correlation of tiller count and cane diameter with cane yield. Path analysis revealed the highest positive direct effect of millable cane number (0.812) on cane yield followed by single cane weight (0.682) and pol percent (0.550). However, stalk diameter and brix percent had considerable negative direct effects and indirect positive effects through single cane weight on cane yield. Therefore, in view of their significant positive association with cane yield, indirect effects of stalk diameter and brix percent via single cane weight should be considered during selection. Genotypes should be selected on the basis of millable cane number, single cane weight and pol percent for getting higher cane and sugar yield.

Smallholder sugarcane production sector is under researched and underdeveloped with limited industrial link and support. The objectives of this study were to assess the current state of sugarcane production, farmers' perceived production constraints and preferred traits, and to collect germplasm grown by smallholder farmers in southern Ethiopia for strategic breeding and conservation. The study was conducted across 16 administrative zones, 28 districts and 56 peasant associations involving 560 smallholder sugarcane growers in southern Ethiopia using a participatory rural appraisal (PRA) approach. Sugarcane genetic resources were collected through structured sampling. Findings from this study indicated that monocropping was identified as the predominant sugarcane farming system. Respondent farmers prioritized drought tolerance (21%), increased cane yield (20%), early maturity (18%), marketability (17%), and Downloaded by [76.179.95.103] at 20:58 04 June 2016high biomass (14%) as the top preferred traits of sugarcane. Ninety diverse sugarcane landraces were collected from homesteads of smallholder farmers. Findings from this study would serve as baseline information towards sugarcane research and development emphasising the constraints and preferences of smallholder sugarcane growers in Ethiopia or similar agro-ecologies. This is the first study to report farmers preferred traits and constraints, and genetic resources of sugarcane under smallholder farming systems in Ethiopia.

Information about the amount and distribution of genetic variation in germplasm collections is important for their efficient management and effective utilization in plant breeding. Therefore this study was conducted to assess genetic diversity of sugarcane germplasm in Ethiopia. An experiment comprising of 400 sugarcane genotypes (174 local and 226 introduced) was conducted between March 2012 and October 2013 at Wonji and Metehara Sugar Estates using partial balanced lattice design with two replications. Data was recorded on 21 quantitative characters which included cane yield and its components, sugar yield and sugar quality traits. ANOVA portrayed highly significant differences (P < 0.01) among the genotypes for 21 quantitative traits. Cluster analysis revealed intra cluster D 2 values ranging from 2.16 -10.60 and inter cluster from 7.24 -5864. There were six principal components accounting for 79.26% of the total variation in the tested materials. Millable stalk count, single cane weight, stalk diameter, cane yield, sugar yield and sugar quality traits showed high positive loading on the first two PCs and accounted for most of the variation observed among the genotypes. Therefore, this study suggested that the important characters responsible for diversity in the sugarcane genotypes could be grouped in two principal components namely "Yield" and "Quality" with "Yield" traits being comparatively more important than "Quality". Genotypes clustered for high mean values of various traits could be exploited for further improvement of the crop either through selection or through hybridization. The clusters having high mean value for yield could be selected for yield per se as well.

Biological control of sugarcane smut (Ustilago scitaminea Syd.) using Trichoderma isolates is one of the untapped potentials in Ethiopian sugarcane plantations. To this end, this study was carried out with the objective to identify potential native Trichoderma isolates for the management of sugarcane smut. A total of 120 soil samples were collected from Kesem, Metehara, and Wonji sugarcane plantation fields. Consequently, 21 Trichoderma isolates were recovered from the samples, and in-vitro antagonist study of Trichoderma isolates against U. scitaminea was done using dual culture technique on fresh PDA. Among the native isolates, 12 of them revealed a pathogen suppression potential of >90% at 7 days after inoculation and most of them had higher pathogen suppression than the commercial isolate. However, five of the isolates were selected as potential candidates based on distinct suppression features, growth rate, and antagonistic performance. Identification of the five effective Trichoderma isolates (WI4-27, MKI2-k17, MI3-m33, WI12-25, and MKI3) was done based on macroscopic and

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