scholarly journals Genetic Variability of Tef [Eragrostis Tef (Zucc.) Trotter] Genotypes for Acid Soil Tolerance

2019 ◽  
pp. 162-171
Author(s):  
Misgana Merga ◽  
Hussein Mohammed ◽  
Kebebew Assef

Genetic variability studies provide basic information for breeders to develop different stress-tolerant varieties. In the present study, forty-nine Tef genotypes were evaluated under strong acid soil (pH 4.97) and lime treated (pH 5.90) soils in the lathouse at Assosa Agricultural Research Center in 2017 to estimate the genetic variability, heritability and genetic advance of various traits of tef genotypes in relation to soil acidity stress. The result indicated that there was high significant (p<0.01) differences among genotypes for all traits under both environments; except for shoot biomass in the combined data analysis. The two environments differed significantly in their effect on all traits except on plant height, panicle length, culm length, total and fertile tillers and number of primary branches, although environment contribution to total TSS was less than 10% in 13 of the 17 traits studied; its high contribution was to harvest index (42.6%) and grain yield pot-1 (32.5%). Big reduction due to soil acidity was recorded for yield of primary panicle (27.78%), grain yield pot-1 (33.85%) and harvest index (35.6%). A contribution of G was from 44.5% in harvest index to 90.5% in panicle length. The GxE interaction was also significant for all traits and it contributed more than 15% in 11 of the traits, indicating inconsistency of performance of genotypes under acidic and lime treated soils. PCV, GCV, and GAM were high (>20%) for fertile tillers per plant, panicle weight, yield of primary panicle, grain yield, and harvest index under both acidity levels and in the combined analysis. Heritability was high (>60%) for all traits except for shoot biomass in the combined analysis and lime treated soil. In general, there was wide genetic variability in the traits studied pointing to the possibility of improving the desired traits, including grain yield under both environments and over environments through the selection of elite genotypes.

1970 ◽  
Vol 18 ◽  
pp. 1-8
Author(s):  
SK Yadav ◽  
BG Suresh ◽  
Praveen Pandey ◽  
Binod Kumar

Context: Direct selection based on crop yields is often a paradox in breeding programmes because yield is a complex polygenically inherited character, influenced by its component traits.   Objectives: The present research work was taken up to assess genetic variability, phenotypic and genotypic associations between various components of grain yield to provide basis for selection and yield improvement in rice.   Materials and Methods: Correlation coefficient and path association are used to find out the degree (strength) and direction of relationship between two or more variable and for fixing up the characters which are having decisive role in influencing the yield. Therefore, a field experiment was carried out to establish the extent of association between yield and yield components and others characters in rice. Analysis of variance revealed that significant amount of genetic variability was present in the entire characters studied.   Results: High heritability coupled with high to moderate genetic advance as % of mean was observed on plant height seed yield per plant, biological yield, harvest index, test weight and number of spikelets per panicle suggesting preponderance of additive gene action in the expression of these characters. The correlation coefficient between seed yield per plant and other quantitative attributing to yield showed that grain yield was significantly and positively associated with harvest index, number of tillers per hill, number of panicle per plant, panicle length, number of spikelet's per panicle and test weight at both genotypic and phenotypic levels. Path coefficient at genotypic level revealed that harvest index, biological yield, number of tillers per hill, panicle length, number of spikelets per panicle, plant height and test weight had direct positive effect on seed yield per hill, indicating these are the main contributors to yield.Conclusion: From the correlation and path study it may be concluded that harvest index, number of tillers per hill, panicle length, and number of spikelet per panicle and test weight are the most important characters that contributed directly to seed yield per hill. Thus a genotype with higher magnitude of these traits could be either selected from existing genotypes or evolved by breeding program for genetic improvement of yield in rice.   Key words: Rice; variability; heritability; agro-morphological traits; correlation; pathDOI: http://dx.doi.org/10.3329/jbs.v18i0.8767 JBS 2010; 18(0): 1-8


Genetika ◽  
2007 ◽  
Vol 39 (2) ◽  
pp. 251-258
Author(s):  
R.M. Pandey

Combining ability, heterosis and inbreeding depression were estimated in grain amaranths for ten characters. Non-additive genetic variance was predominant for majority of characters in both F1 and F2 generations. The parent AG-21 was good general combiner for yield/plant also showed high GCA effects for panicles/plant and harvest index in both F1 and F2 generations. Seven characters, the best F2s on the basis of SCA involves one parent with high GCA effect and the other with poor or average GCA effects. The hybrids which exhibited highest heterosis also showed high inbreeding depression. Heterosis over better parent was highest for economic grain yield (145.047%), followed by panicles/plant (113.675%), panicle length (33.656%) and grain weight/panicle (23.566%).


2007 ◽  
Vol 58 (8) ◽  
pp. 816 ◽  
Author(s):  
P. M. Damon ◽  
Z. Rengel

A novel approach to the sustainable management of potassium (K) resources in agro-ecosystems is through better exploitation of genetic differences in the K efficiency of crop plants. Potassium efficiency is a measure of genotypic tolerance to soils with low potassium availability and can be quantified as the K efficiency ratio (the ratio of growth at deficient and adequate K supply). This study investigated the magnitude of variation in K efficiency among wheat (Triticum aestivum L.) genotypes grown in a glasshouse and in the field. Genotypes differed significantly in response to low soil K availability in terms of shoot biomass during the vegetative growth phase and grain yield at maturity under glasshouse (144 genotypes) and field (89 genotypes) conditions. K-efficient and K-inefficient genotypes were identified. The main factor determining K efficiency for grain yield was the capacity of genotypes to maintain a high harvest index (grain yield/total shoot weight) at deficient K supply. Genotypes that had reduced harvest index under deficient K supply were K-inefficient. Capacity to tolerate low concentrations of K in shoot tissue where K supply was deficient was also important in determining K efficiency for grain yield. Potassium-efficient genotypes have the potential to enhance the productivity and sustainability of cereal cropping systems.


1970 ◽  
Vol 23 (1) ◽  
pp. 19-30
Author(s):  
MM Islam ◽  
U Sarker ◽  
MG Rasul ◽  
MM Rahman

An experiment was conducted to study the heterosis of 27 F1 hybrids produced from nine CMS lines and three restorer lines of rice with their parental lines and BRRI Dhan29 as standard check for 17 yield and its contributing traits. Mid parent, better parent and standard heterosis of most of the crosses were significant for most of the characters studied either in positive or in negative direction. Desirable and significant mid parent and better parent heterosis was observed in 13 and seven cross combinations, respectively for grain yield and most of its related traits. Considering more than 20% mid parent and better parent heterosis for grain yield along with most of its related traits, nine and five cross combinations, respectively were identified as good heterotic combinations over mid parental and better parental value. On the basis of individual trait significant and desirable mid parent heterosis was observed in eight cross combinations for plant height, 12 for leaf blade length, nine for flag leaf blade length, 13 for flag leaf sheath length, eight for tillers per hill, eight for panicles per hill, 14 for days to 50% flowering, four for days to maturity, four for panicle length, 14 for panicle weight, nine for primary branches per panicle, 16 for secondary branches per panicle, six for filled grains per panicle, 15 for 1000 seed weight, 13 for grain yield per hill and 15 for harvest index. Significant and desirable better parent heterosis was observed in 12 cross combinations for plant height, 11 for leaf blade length, 5 for flag leaf blade length, nine for flag leaf sheath length, seven for tillers per hill, seven for panicles per hill, 25 for days to 50% flowering, one for days to 100% flowering, seven for days to maturity, three for panicle length, nine for panicle weight, five for primary branches per panicle, 12 for secondary branches per panicle, four for filled grains per panicle, nine for 1000 seed weight, seven for grain yield per hill and nine for harvest index. None of the crosses were identified as good heterotic over standard check for grain yield per hill but many good and desirable heterotic crosses were identified over standard check for most of the yield related characters. Twenty cross combinations were identified as heterotic over standard check due to desirable and significant standard heterosis for most of the yield related traits.   Keywords: Heterosis; rice; Oryza sativa; boro DOI: http://dx.doi.org/10.3329/bjpbg.v23i1.9314 BJPBG 2010; 23(1): 19-30


2018 ◽  
Vol 10 (2) ◽  
pp. 797-804
Author(s):  
Satnam Singh Nagar ◽  
Pradeep Kumar ◽  
S.R. Vishwakarma ◽  
Gyanendra Singh ◽  
B. S. Tyagi

A study was conducted for estimating genetic variability and characters association for eleven yield components using 169 genotypes (13 parents, 78 F1 and 78 F2) of bread wheat through half-diallel mating design during rabi season 2012-13 and 2013-14. The genetic variability, heritability in broad sense, genetic advance, correlation coefficients and path analysis were carried out for the assessment of genotypes through eleven yield component traits namely; days to 50% flowering, days to maturity, plant height, spike length, number of effective tillers per plant, number of grains per spikelet, number of grains per spike, 1000-grain weight, biological yield per plant, harvest index and grain yield per plant. Analysis of variance showed significant differences (at1% level of significance) for all the traits under study in both the generations (F1 and F2). The phenotypic coefficient of variation (PCV) and genotypic coefficient of variation (GCV) were high for plant height followed by number of effective tillers per plant, biological yield per plant, grain yield per plant, while high heritability coupled with high genetic advance were recorded for plant height and spike length in both F1 and F2 generations, respectively. Grain yield per plant was positively and significantly associated with a number of effective tillers per plant, spike length, number of grains per spike, 1000-grain weight, biological yield per plant and harvest index while significantly but negatively associated with plant height. Path analysis revealed that the traits namely biological yield per plant, number of effective tillers per plant, number of grains per spike, plant height and harvest index exhibited positive direct effects on grain yield at both phenotypic and genotypic level in both generation (F1 and F2). These results, thereby suggests that yield improvement in breads wheats could be possible by emphasizing these traits while making selections in early generations.


Author(s):  
Babburi Dinesh ◽  
Gaibriyal M. Lal ◽  
L. Bhanuprasad

A set of twenty four rice genotypes including one check variety were grown to estimate study genetic variability, heritability, genetic advance, correlation and path coefficient for 13 quantitative characters, observation recorded to study the genetic variability parameters, correlation coefficient and path coefficient for yield and its attributing traits. High to moderate estimates of GCV and PCV were recorded for test weight followed by spikelets per panicle, grain yield per plant, flag leaf width, flag leaf length, tillers per hill, biological yield and panicles per hill. Grain yield indicated significant positive correlation with plant height followed by tillers per hill, panicles per hill, biological yield and harvest index in terms of phenotypic correlation coefficient whereas in terms of genotypic coefficient it showed positive and significant correlation with plant height, tillers per hill, panicles per hill, biological yield and harvest index. Path coefficient analysis showed positive significant direct effects on grain yield per hill were exhibited by plant height, tillers per hill and harvest index at genotypic level whereas it showed positive and significant direct effect for tillers per hill, flag leaf width, biological yield and harvest index at phenotypic level. Thus, these traits are identified as the efficient and potential for indirect selection for the improvement of rice productivity in the present experimental materials.


Author(s):  
M. S. Nikam G. C. Shinde ◽  
V. R. Awari M. S. Shinde ◽  
N. S. Kute

The forty four promising sorghum genotypes were evaluated for variability, correlation and path analysis for yield and yield contributing characters, at Sorghum improvement Project, Mahatma Phule Krishi Vidyapeeth, Rahuri during Rabi-2019-20. High estimates of PCV and GCV were observed for traits no. of green leaves per plant at harvest, panicle length (cm), panicle width (cm), panicle weight (g), harvest index and grain yield per plant (g).High estimates of heritability along with high genetic advance were recorded for plant height (cm), no. of green leaves per plant at harvest, panicle length (cm), panicle width (cm), panicle weight (g), 1000 grain weight (g), dry fodder yield per plant (g), harvest index and grain yield per plant (g).Correlation studies revealed a positive and significant association of grain yield with plant height (cm), number of internodes per plant, number of green leaves per plant at harvest, panicle length (cm), panicle width (cm), panicle weight (g), 1000 grain weight (g), dry fodder yield per plant (g) and harvest index at both genotypic and phenotypic level. Harvest index, panicle weight, dry fodder yield per plant, days to maturity and no. of internodes per plant recorded high magnitudes of direct effects accompanied by highly significant correlation with the grain yield at genotypic level, indicating true and perfect relationship between them. Thus suggesting that selection for these traits viz., harvest index, panicle weight, dry fodder yield per plant, days to maturity and no. of internodes per plant will be highly rewarding for improving the grain yield per plant.


2015 ◽  
Vol 2 (2) ◽  
pp. 261-269
Author(s):  
Shompa Rani Debnath ◽  
Md Sultan Uddin Bhuiya ◽  
M Rafiqul Islam ◽  
Md Mahboob Karim ◽  
ABM Shafiul Alam

The experiment was conducted at the Agronomy Field Laboratory, Bangladesh Agricultural University, Mymensingh during July to December 2013 in the aman season to investigate the effect of age of seedling and nitrogen rates in the nursery bed on growth, yield and yield components of BRRI dhan52. The experiment comprised of three ages of seedlings viz., 30, 35 and 40 day old and four nitrogen rate N1-N@50 kg ha-1, N2-N@75 kg ha-1, N3-N@100 kg ha-1, N4-N@125 kg ha-1. The experiment was laid out in a split plot design with three replications. Age of seedling showed significant differences for shoot weight, survivor, no. grains panicle-1, panicle length, grain yield and straw yield. The highest root weight (0.072 gm-2), plant height (108 cm), total tillers hill-1 (8.22), effective tillers hill-1 (7.03), non-effective tillers hill-1 (1.19), survivor (95.1%), grains panicle-1 (106.2), grain yield (5.57 t ha-1), straw yield (6.26 t ha-1) and harvest index (0.47%) were found by transplanting 40 day old seedlings. The highest shoot weight (0.53 gm-2), 1000 grain wt. (25.3g) was found by transplanting 35 day old seedlings and 30 day old seedlings produced highest sterile spikelets (28.9) and panicle length (23.8 cm). Nitrogen rate in the nursery showed significant differences for shoot weight, root weight, survivor, plant height, total tillers hill-1, effective tillers hill-1, non-effective tillers hill-1, panicle length, grains panicle-1, grain yield and straw yield. Application of 50 kg N ha-1 gave higher plant height (108 cm) and harvest index (0.47%). On the other hand, application of 75 kg N ha-1 produced highest non–effective tillers hill-1 (1.0), grains panicle-1 (100.7), 1000 grain weight (25.3 g) and harvest index (0.47%). Application of 100 kg N ha-1 gave highest total tillers hill-1 (7.85), effective tillers hill-1 (6.85), non–effective tillers hill-1 (1.0), survivor (90.5%) and grain yield (5.01 t ha-1). Application of 125 kg N ha-1 gave highest panicle length (23.75 cm), grains panicle-1 (100.7), non–effective tillers hill-1 (1.0) and sterile spikelets (30.1). Forty day old seedlings grown with 100 kg N ha-1 at nursery found to be better in respect of grain yield. The result of the experiment also showed that aged seedlings regenerated quickly after desubmerge of water.Res. Agric., Livest. Fish.2(2): 261-269, August 2015


2018 ◽  
Vol 44 (4) ◽  
pp. 581-589
Author(s):  
AK Singh ◽  
RK Singh ◽  
Sunil Kumar ◽  
M Arya ◽  
PK Singh

One hundred F2 and F3 single plant progenies along with their parents and the infector rows were evaluated for 13 quantitative traits to assess the genetic variability, heritability, associations and estimation of number of genes for bacterial leaf blight resistance and yield related traits. In both F2 and F3, a wide range of variability was present for all the traits, indicating considerable scope for selection. High heritability accompanied with high genetic advance was observed for plant height, panicle length, panicle weight, number of effective tillers per plant and grain yield per plant. Positive and significant correlation were observed between grain yield per plant with days to 50% flowering, plant height, panicle length, panicle weight, number of effective tillers per plant, test weight and flag leaf length in either one of the generation or in combination of both F2 and F3. Path-coefficients analysis showed that plant height, panicle length and test weight had high direct positive effect in both the F2 and F3. The estimated number of gene(s) in the segregating generations for bacterial leaf blight was 2.14 in the F2 and 0.92 in the F3 revealed that two genes were involved in the inheritance of resistance to bacterial leaf blight in F2, while only one gene in F3 due to dominance effect.


2007 ◽  
Vol 20 (1) ◽  
pp. 39-45
Author(s):  
Khaleda Akter ◽  
S. H. Habib ◽  
M. K. Bashar ◽  
A. M. Nurunnabi

Thirty advanced breeding lines of deep-water rice were evaluated during T. Aman season (rainfed ecosystem) with a view to finding out variability and genetic association for grain yield and its component characters. All the tested characters showed significant variation. The highest genetic variability was obtained in filled grains/panicle followed by plant height. Panicles/plant, filled grains/panicle and grain yield had high genetic coefficient of variation and heritability in broad sense coupled with high genetic advance in percentage of mean. Panicle length, panicles/plant, plant height, filled grains/panicle and harvest index showed significant positive association with grain yield. Path coefficient analysis also revealed maximum positive and direct contribution of filled grain to grain yield followed by panicles/plant, 1000-grain weight and flag leaf area. Moreover, plant height had the highest indirect effect on grain yield through filled grains/panicle. Flag leaf area, harvest index and panicle length also had higher positive indirect effect on grain yield through filled grains/panicle.DOI: http://dx.doi.org/10.3329/bjpbg.v20i1.17024


Sign in / Sign up

Export Citation Format

Share Document