Genetic Variability and Traits Association Study in Rainfed Lowland Rice (Oryza sativa L.) Genotypes in Southwestern Ethiopia
Abayneh Kacharo,
Wosene Gebreselassie,
Techale Birhan
Issue:
Volume 9, Issue 3, September 2021
Pages:
42-49
Received:
24 February 2020
Accepted:
23 April 2021
Published:
13 July 2021
Abstract: Background and Objective: Complete knowledge on the extent of genetic variability and interrelationships of yield and components traits is pre-request for designing an effective and efficient selection based rice improvement programs for generating high yielding rainfed lowland rice genotypes. The objective of this study was in order to determine the extent of genetic variability and association of characters with grain yield and among themselves. Materials and Methods: Twenty-five rainfed lowland rice genotypes were evaluated during the 2016 main cropping season at two rainfed lowland agro-ecologies of Southwestern Ethiopia. The experiment was laid out in a simple lattice design and data on 14 yield and yield component traits were collected and subjected to various statistical analyses. Results: Combined analysis of variance across locations revealed significant location, genotype and genotype x location interaction effects for several traits evaluated at p ≤ 0.01. The phenotypic coefficient of variation (PCV) ranged from 2.14% for days to 85% maturity to 18.09% for grain yield, while the genotypic coefficient of variation (GCV) ranged from 0.71% for days 85% to maturity to 10.48% for grain yield. Heritability estimate in broad sense was high for plant height (74.15) and low for days to 85% maturity (11.06) and harvest index (23.47). Plant height displayed high heritability along with moderate genetic advance as percent of mean value and days to 85% maturity and harvest index exhibited low GCV, heritability and genetic advance as percentage of mean estimates. Correlation coefficient analysis of grain yield showed positive and significant association with number of primary branches per panicle at both phenotypic and genotypic levels. Separation of correlation coefficients into direct and indirect effects of component traits on grain yield revealed that number of primary branches per panicle exerted the maximum positive direct effect on grain yield at both genotypic and phenotypic levels. Conclusion: The present study indicated sufficient amount of genetic variability for the majority of the characters studied in rainfed lowland rice genotype for future exploitation in selection based improvement programs.
Abstract: Background and Objective: Complete knowledge on the extent of genetic variability and interrelationships of yield and components traits is pre-request for designing an effective and efficient selection based rice improvement programs for generating high yielding rainfed lowland rice genotypes. The objective of this study was in order to determine t...
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Genetic Variability and Associations of Yield and Yield Related Traits for Fieldpea (Pisum stivum L.) Genotypes in Arsi Zone, Southeastern Ethiopia
Gizachew Yilma Kebede,
Gebeyaw Achenef Haile,
Temesgen Abo
Issue:
Volume 9, Issue 3, September 2021
Pages:
50-55
Received:
16 July 2021
Accepted:
27 July 2021
Published:
4 August 2021
Abstract: Field pea is an important pulse crops in Ethiopia, however the production is reduced due to many constraints including limited availability of improved variety and traditional farming systems. Twenty five advanced field pea genotypes were evaluate for ten traits at three locations during 2015/16 main cropping season using RCBD with two replications. Thus the objectives of this study were to estimate genetic variability of the genotypes and to assess the associations of yield and yield related traits. The ANOVA result showed that significant variation among genotypes. Mean square from genotype by environment interaction showed that highly significant variation among the genotypes for all traits. The genotypic and phenotypic coefficient of variation ranged from 2.4 to 12.9 and 2.9 to 22 respectively. Heritability estimates and genetic advance as present of mean also ranged from 20% to 90% and from 2.2% to 25.8% respectively. Higher estimate of heritability recorded from days to 50% flowering and thousand seed weight. Grain yield showed a significant and negative genotypic association with plant height and stand count. Stand count, days to 50% flowering, thousands seed weight and powdery mildew have a negative direct effects on grain yield while plant height has appositive direct effect on grain yield. The first two principal components explained about 58.36% of the total variation among the genotypes. The first components explained about 38.97% of the total variation and mostly explained by stand count, powdery mildew and days to 50% flowering. So the research gives as clear information about the 25 field pea genotypes for future breeding strategy.
Abstract: Field pea is an important pulse crops in Ethiopia, however the production is reduced due to many constraints including limited availability of improved variety and traditional farming systems. Twenty five advanced field pea genotypes were evaluate for ten traits at three locations during 2015/16 main cropping season using RCBD with two replications...
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Prediction of Body Weight from Linear Body Measurements for Horro Sheep Breeds in Oromia, Ethiopia
Dereje Bekele,
Tesfaye Tadesse
Issue:
Volume 9, Issue 3, September 2021
Pages:
56-60
Received:
25 July 2021
Accepted:
9 September 2021
Published:
29 September 2021
Abstract: The study was carried out in Bako Agricultural Research Center’s sheep farm and Horro district to determine the relationship between live weight and linear measurements and predict live weight from morphometric traits and morphometric measurements from 1589 Horro sheep (1131 female and 456 male) were used to determine relationships between body weight and linear body measurements. Accordingly, Body weight, Body length, Height at wither, Chest girth, Chest width, Rump length and Pelvic width measurements were recorded for each animal. Correlation and regression analysis between body weight and the linear body measurements were conducted independently for male and female within the different age categories defined using dentition. In most of the analyses, there was a significantly (p<0.001) higher correlation between body weight and the linear body measurements. Chest girth has showed the most higher and consistent correlation with body weight in both sex and the different age categories. Based on the correlation results chest girth was primarily used to fit the equation for prediction of body weight in stepwise regression. Thus, the general equations developed from the regression analyses were based only on sex rather than for different age categories. As a result the equations BW= -24.24 + 0.68CG for male Horro sheep, and BW= -29.03 + 0.75CG for female Horro sheep can accurately predict body weight of the breed at any age.
Abstract: The study was carried out in Bako Agricultural Research Center’s sheep farm and Horro district to determine the relationship between live weight and linear measurements and predict live weight from morphometric traits and morphometric measurements from 1589 Horro sheep (1131 female and 456 male) were used to determine relationships between body wei...
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