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Ashok Kumar Singh - One of the best experts on this subject based on the ideXlab platform.
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differential rna editing of mitochondrial genes in wa cytoplasmic based male sterile line pusa 6a and its maintainer and Restorer Lines
Rice Science, 2019Co-Authors: Umakanta Ngangkham, Ashok Kumar Singh, Swarup K Parida, Trilochan MohapatraAbstract:Abstract RNA editing changes the nucleotides at the transcript level of mitochondrial genes which results in synthesis of functional proteins. This study was designed to find the editing sites which could be implicated in male fertility restoration and to develop editing based markers for differentiation of cytoplasmic male sterility and maintainer Lines from each other. DNA and RNA from young panicles were isolated from three-line system of hybrid rice PRH10, wild abortive (WA) cytoplasm based male sterile (A line Pusa 6A), maintainer (B line Pusa 6B) and Restorer (R line PRR78) Lines. Pusa 6A and PRR78 having the same WA cytoplasm are allo-nuclear and iso-cytpolasmic Lines. The genomic and cDNA amplicons for eight mitochondrial genes (18SrRNA, atp6, atp9, cobII, coxI, coxIII, nadI and rps3) were sequenced and compared. Differences in genomic and cDNA sequences were considered as editing. Two hundred and thirty editing sites having base substitution or insertion/deletion were identified with the highest in 18SrRNA (5.74%) and the lowest in coxI (0.60%). The highest editing sites were observed in fertile maintainer Pusa 6B followed by PRR78 and Pusa 6A, of which random five editing sites in five different rice mitochondrial transcripts namely atp9, cobII, coxIII, rps3 and 18SrRNA were chosen and validated through cleaved amplified polymorphism sequence (CAPS) analysis and found to be partially edited in four genes. The identical editing sites of different mitochondrial genes from maintainer and Restorer Lines might reflect their possible contribution to fertility restoration of sterile WA cytoplasm.
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marker assisted identification of Restorer gene s in iso cytoplasmic Restorer Lines of wa cytoplasm in rice and assessment of their fertility restoration potential across environments
Physiology and Molecular Biology of Plants, 2017Co-Authors: Amit Kumar, Prolay Kumar Bhowmick, Vikram Jeet Singh, Manoj Malik, Ambrish Gupta, Rakesh Seth, M Nagarajan, Subbaiyan Gopala Krishnan, Ashok Kumar SinghAbstract:Iso-cytoplasmic Restorers possess the same male sterile cytoplasm as the cytoplasmic male sterile (CMS) Lines, thereby minimizing the potential cyto-nuclear conflict in the hybrids. Restoration of fertility of the wild abortive CMS is governed by two major genes namely, Rf3 and Rf4. Therefore, assessing the allelic status of these Restorer genes in the iso-cytoplasmic Restorers using molecular markers will not only help in estimating the efficiency of these genes either alone or in combination, in fertility restoration in the hybrids in different environments, but will also be useful in determining the efficacy of these markers. In the present study, the efficiency of molecular markers in identifying genotypes carrying Restorer allele of the gene(s) Rf3 and Rf4, restoring male fertility of WA cytoplasm in rice was assessed in a set of 100 iso-cytoplasmic rice Restorers using gene linked as well as candidate gene based markers. In order to validate the efficacy of markers in identifying the Restorers, a sub-set of selected 25 iso-cytoplasmic rice Restorers were crossed with four different cytoplasmic male sterile Lines namely, IR 79156A, IR 58025A, Pusa 6A and RTN 12A, and the pollen and spikelet fertility of the F1s were evaluated at three different locations. Marker analysis showed that Rf4 was the predominant fertility Restorer gene in the iso-cytoplasmic Restorers and Rf3 had a synergistic effect on fertility restoration. The efficiency of gene based markers, DRCG-RF4-14 and DRRM-RF3-10 for Rf4 (87%) and Rf3 (84%) genes was higher than respective gene-linked SSR markers RM6100 (80%) and RM3873 (82%). It is concluded that the gene based markers can be effectively used in identifying fertility Restorer Lines obviating the need for making crosses and evaluating the F1s. Though gene based markers are more efficient, there is a need to identify functional polymorphisms which can provide 100% efficiency. Three iso-cytoplasmic Restorers namely, PRR 300, PRR 363 and PRR 396 possessing both Rf4 and Rf3 genes and good fertility restoration have been identified which could be used further in hybrid rice breeding.
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development and evaluation of iso cytoplasmic rice Restorer Lines for different agro morphological traits
Indian Journal of Genetics and Plant Breeding, 2017Co-Authors: Amit Kumar, Prolay Kumar Bhowmick, Gopala S Krishnan, Ashok Kumar SinghAbstract:A set of 390 iso-cytoplasmic Restorer Lines were developed from 25 popular rice hybrids grown in India through pedigree breeding exercising selection for spikelet fertility, yield and extent of panicle exsertion were evaluated for various agromorphological traits. Correlation analysis showed that yield per plant was significantly correlated with number of tillers (0.208), panicle length (0.127) and spikelet fertility (0.134). Principal component analysis indicated that the first four principal components had eigenvalue of > 1.0 and cumulatively explained 74.3% of total variance. Grain characters namely, test weight (0.451), kernel length before cooking (0.418), kernel breadth before cooking (0.136) and spikelet fertility (0.402) contributed positively towards principal component I. Yield per plant showed a positively skewed distribution with panicle length and a nearly linear relationship with spikelet fertility. A core set of 21 genotypes capturing the entire range of phenotype for different traits, was identified from 390 genotypes using advanced M (maximization) strategy and statistically validated. Besides this, promising iso-cytoplasmic Restorer Lines originating from different hybrids were identified for various agromorphological traits. This is the first report on developing iso-cytoplasmic Restorers from popular rice hybrids, which can be used in developing heterotic hybrids when crossed with diverse non-parental CMS Lines.
M K Dhillon - One of the best experts on this subject based on the ideXlab platform.
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inheritance of resistance to spotted stem borer chilo partellus in sorghum sorghum bicolor
Euphytica, 2007Co-Authors: H C Sharma, M K Dhillon, G Pampapathy, Belum V S ReddyAbstract:The spotted stem borer, Chilo partellus, is one of the most important pests of sorghum, and host plant resistance is an important component for the management of this pest. Most of the sorghum hybrids currently under cultivation are based on cytoplasmic male-sterility (CMS). In order to develop a strategy for resistance to stem borer, we studied the traits associated with resistance, and their nature of gene action in F1 hybrids derived from resistant, moderately resistant, and susceptible CMS and Restorer Lines. The hybrids based on stem borer-resistant, moderately resistant, or susceptible CMS and Restorer Lines were equally resistant or susceptible as the parents for leaf feeding [Damage rating (DR) 5.8 to 6.6 vs. 5.9 to 6.6], and had significant and decreasing trend in deadheart formation (resistant CMS × resistant Restorer Lines < moderately resistant CMS × moderately resistant Restorer Lines < susceptible CMS × susceptible Restorer Lines), respectively. Proportional contributions of Restorer Lines were greater than those of the CMS Lines for leaf feeding, deadhearts, recovery and overall resistance, stalk length, nodes per plant, stem borer holes per plant, and peduncle tunneling. The general (GCA) and specific combining ability (SCA) estimates suggested that leaf feeding score, number of nodes, overall resistance score, panicle initiation, recovery score, and stalk length (dominance type of gene action) have been found to be associated with resistance to spotted stem borer, governed by additive type of gene action, their correlation and direct effects in the same direction, and explained 65.3% of the variation in deadhearts, and thus could be used as marker traits to select and breed for resistance to C. partellus in sorghum. The parents having significant SCA effects for two or more resistance traits for either or more parents have also been discussed for their use in the stem borer resistance breeding.
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multiple resistance to sorghum shoot fly spotted stemborer and sugarcane aphid in sorghum
International Journal of Tropical Insect Science, 2006Co-Authors: H C Sharma, M K Dhillon, G PampapathyAbstract:Sorghum is one of the most important cereal crops in the semi-arid tropics. Several insect pests damage it. The possibility of identifying genotypes with multiple resistance to these pests and transferring the relevant genes into high-yielding varieties and hybrids has been considered as an attractive approach to reducing yield losses. A set of 12 cytoplasmic male-sterile and maintainer Lines, 12 Restorer Lines and their F1 hybrids were evaluated for resistance to sorghum shoot fly Atherigona soccata Rondani, spotted stemborer Chilo partellus (Swinhoe) and sugarcane aphid Melanaphis sacchari (Zehntner) under field conditions. There were significant differences among the genotypes tested. A total of 50% of male-sterile Lines, 41.7% maintainers, 58.3% Restorers and 35.4% of the hybrids tested showed moderate to high level of resistance to the three pests. The male- sterile and Restorer Lines showing resistance to different insects can be exploited for developing hybrids with multiple insect resistance for cultivation by the resource-poor farmers in the semi-arid tropics.
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expression of resistance to atherigona soccata in f1 hybrids involving shoot fly resistant and susceptible cytoplasmic male sterile and Restorer Lines of sorghum
Plant Breeding, 2006Co-Authors: H C Sharma, M K Dhillon, Belum V S ReddyAbstract:In recent years, cytoplasmic male-sterility (CMS) has been recognized as a potential danger to the stability of crop production and resistance to insect pests in sorghum. Therefore, the influence of CMS on the expression of resistance to sorghum shoot fly was studied at the ICRISAT, Patancheru, India using the interlard fishmeal technique. The experimental material consisted of 12 Restorer, 12 CMS and the maintainer Lines, and their 144 F1 hybrids. Shoot fly-resistant CMS Lines were preferred for oviposition and had more damage because of deadhearts than the corresponding maintainer Lines. The hybrids based on shoot fly-resistant CMS × resistant Restorer Lines were significantly less preferred for oviposition than the hybrids based on other cross combinations and exhibited the highest frequency (69.1%) of shoot fly-resistant hybrids. The hybrids based on glossy and trichomed parents had the highest frequency (>90%) of hybrids with glossy and trichome traits, emphasizing the need to transfer these traits into both parents for better expression in the F1 hybrids. The expression pattern of trichome density, leaf glossiness and leaf sheath pigmentation in the F1 hybrids and their parents suggested that the interactions between cytoplasmic and nuclear genes possibly control the expression of traits associated with resistance to sorghum shoot fly in the F1 hybrids.
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inheritance of resistance to sorghum shoot fly atherigona soccata
Crop Science, 2006Co-Authors: M K Dhillon, Belum V S Reddy, H C Sharma, Ram Singh, J S NareshAbstract:The sorghum shoot fly, Atherigona soccata Rond. (Diptera: Muscidae), is one of the most important pests of sorghum [Sorghum bicolor (L.) Moench], and host plant resistance is an important component for the management of this pest. Most of the sorghum hybrids currently under cultivation are based on cytoplasmic malesterility (CMS). To develop a strategy to develop sorghum hybrids with resistance to shoot fly, we studied the nature of gene action for resistance to this pest in F1 hybrids derived from shoot fly-resistant and -susceptible CMS and Restorer Lines. The hybrids based on shoot flyresistant CMS and Restorer Lines were glossy and trichomed and had lower proportion of plants with eggs (78.5% vs. 88.4 to 93.3%) and deadhearts (40.8% vs. 60.8 to 75.3%) than the hybrids based on other cross combinations, suggesting that resistance is required in both CMS and Restorer Lines for obtaining shoot fly-resistant hybrids. Proportional contributions of CMS Lines for oviposition, deadhearts, leaf glossiness, and recovery resistance were greater than those of the Restorer Lines. The general (GCA) and specific combining ability (SCA) estimates suggested that inheritance for oviposition nonpreference, deadhearts, recovery resistance, and the morphological traits associated with resistance or susceptibility to A. soccata were governed by additive-type of gene action. The SCA effects and heterosis estimates indicated that heterosis breeding would not be rewarding in breeding for resistance to shoot fly.
Yingguo Zhu - One of the best experts on this subject based on the ideXlab platform.
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development of elite bph resistant wide spectrum Restorer Lines for three and two line hybrid rice
Frontiers in Plant Science, 2017Co-Authors: Fengfeng Fan, Yunping Chen, Xingdan Liu, Heng Sun, Jie Wang, Yingguo ZhuAbstract:Hybrid rice has contributed significantly to the world food security. Breeding of elite high-yield, strong-resistant broad-spectrum Restorer line is an important strategy for hybrid rice in commercial breeding programs. Here, we developed three elite brown planthopper (BPH)-resistant wide-spectrum Restorer Lines by pyramiding big-panicle gene Gn8.1, BPH-resistant genes Bph6 and Bph9, fertility Restorer genes Rf3, Rf4, Rf5 and Rf6 through molecular marker assisted selection. Resistance analysis revealed that the newly developed Restorer Lines showed stronger BPH-resistance than any of the single-gene donor parent Luoyang-6 and Luoyang-9. Moreover, the three new Restorer Lines had broad spectrum recovery capabilities for Honglian CMS, Wild abortive CMS and two-line GMS sterile Lines, and higher grain yields than that of the recurrent parent 9311 under nature field conditions. Importantly, the hybrid crosses also showed good performance for grain yield and BPH-resistance. Thus, the development of elite BPH-resistant wide-spectrum Restorer Lines has a promising future for breeding of broad spectrum BPH-resistant high-yield varieties.
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genetic variation of main Restorer Lines of hybrid rice in china was revealed by microsatellite markers
Acta Genetica Sinica, 2002Co-Authors: Shihua Duan, Jianing Mao, Yingguo ZhuAbstract:A total of thirty-five Restorer Lines of hybrid rice (Oryza sativa L.) were analyzed by twenty-five SSR (simple sequence repeats) primer pairs, which disperse on 12 chromosomes in rice. Those primers detected 65 alleles among 35 Restorer Lines of hybrid rice. Per primer pair detected 2.6 alleles on the average. PIC (polymorphism index content) values ranged from 0.206 to 0.682. PIC value is 0.414 on the average. The result from cluster analysis shows that hybrid rice Restorer Lines have abundant resource in China, but the genetic diversity is small and the genetic background is vulnerable among them. The utilization of rice heterosis was limited seriously.
H C Sharma - One of the best experts on this subject based on the ideXlab platform.
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inheritance of resistance to spotted stem borer chilo partellus in sorghum sorghum bicolor
Euphytica, 2007Co-Authors: H C Sharma, M K Dhillon, G Pampapathy, Belum V S ReddyAbstract:The spotted stem borer, Chilo partellus, is one of the most important pests of sorghum, and host plant resistance is an important component for the management of this pest. Most of the sorghum hybrids currently under cultivation are based on cytoplasmic male-sterility (CMS). In order to develop a strategy for resistance to stem borer, we studied the traits associated with resistance, and their nature of gene action in F1 hybrids derived from resistant, moderately resistant, and susceptible CMS and Restorer Lines. The hybrids based on stem borer-resistant, moderately resistant, or susceptible CMS and Restorer Lines were equally resistant or susceptible as the parents for leaf feeding [Damage rating (DR) 5.8 to 6.6 vs. 5.9 to 6.6], and had significant and decreasing trend in deadheart formation (resistant CMS × resistant Restorer Lines < moderately resistant CMS × moderately resistant Restorer Lines < susceptible CMS × susceptible Restorer Lines), respectively. Proportional contributions of Restorer Lines were greater than those of the CMS Lines for leaf feeding, deadhearts, recovery and overall resistance, stalk length, nodes per plant, stem borer holes per plant, and peduncle tunneling. The general (GCA) and specific combining ability (SCA) estimates suggested that leaf feeding score, number of nodes, overall resistance score, panicle initiation, recovery score, and stalk length (dominance type of gene action) have been found to be associated with resistance to spotted stem borer, governed by additive type of gene action, their correlation and direct effects in the same direction, and explained 65.3% of the variation in deadhearts, and thus could be used as marker traits to select and breed for resistance to C. partellus in sorghum. The parents having significant SCA effects for two or more resistance traits for either or more parents have also been discussed for their use in the stem borer resistance breeding.
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multiple resistance to sorghum shoot fly spotted stemborer and sugarcane aphid in sorghum
International Journal of Tropical Insect Science, 2006Co-Authors: H C Sharma, M K Dhillon, G PampapathyAbstract:Sorghum is one of the most important cereal crops in the semi-arid tropics. Several insect pests damage it. The possibility of identifying genotypes with multiple resistance to these pests and transferring the relevant genes into high-yielding varieties and hybrids has been considered as an attractive approach to reducing yield losses. A set of 12 cytoplasmic male-sterile and maintainer Lines, 12 Restorer Lines and their F1 hybrids were evaluated for resistance to sorghum shoot fly Atherigona soccata Rondani, spotted stemborer Chilo partellus (Swinhoe) and sugarcane aphid Melanaphis sacchari (Zehntner) under field conditions. There were significant differences among the genotypes tested. A total of 50% of male-sterile Lines, 41.7% maintainers, 58.3% Restorers and 35.4% of the hybrids tested showed moderate to high level of resistance to the three pests. The male- sterile and Restorer Lines showing resistance to different insects can be exploited for developing hybrids with multiple insect resistance for cultivation by the resource-poor farmers in the semi-arid tropics.
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expression of resistance to atherigona soccata in f1 hybrids involving shoot fly resistant and susceptible cytoplasmic male sterile and Restorer Lines of sorghum
Plant Breeding, 2006Co-Authors: H C Sharma, M K Dhillon, Belum V S ReddyAbstract:In recent years, cytoplasmic male-sterility (CMS) has been recognized as a potential danger to the stability of crop production and resistance to insect pests in sorghum. Therefore, the influence of CMS on the expression of resistance to sorghum shoot fly was studied at the ICRISAT, Patancheru, India using the interlard fishmeal technique. The experimental material consisted of 12 Restorer, 12 CMS and the maintainer Lines, and their 144 F1 hybrids. Shoot fly-resistant CMS Lines were preferred for oviposition and had more damage because of deadhearts than the corresponding maintainer Lines. The hybrids based on shoot fly-resistant CMS × resistant Restorer Lines were significantly less preferred for oviposition than the hybrids based on other cross combinations and exhibited the highest frequency (69.1%) of shoot fly-resistant hybrids. The hybrids based on glossy and trichomed parents had the highest frequency (>90%) of hybrids with glossy and trichome traits, emphasizing the need to transfer these traits into both parents for better expression in the F1 hybrids. The expression pattern of trichome density, leaf glossiness and leaf sheath pigmentation in the F1 hybrids and their parents suggested that the interactions between cytoplasmic and nuclear genes possibly control the expression of traits associated with resistance to sorghum shoot fly in the F1 hybrids.
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inheritance of resistance to sorghum shoot fly atherigona soccata
Crop Science, 2006Co-Authors: M K Dhillon, Belum V S Reddy, H C Sharma, Ram Singh, J S NareshAbstract:The sorghum shoot fly, Atherigona soccata Rond. (Diptera: Muscidae), is one of the most important pests of sorghum [Sorghum bicolor (L.) Moench], and host plant resistance is an important component for the management of this pest. Most of the sorghum hybrids currently under cultivation are based on cytoplasmic malesterility (CMS). To develop a strategy to develop sorghum hybrids with resistance to shoot fly, we studied the nature of gene action for resistance to this pest in F1 hybrids derived from shoot fly-resistant and -susceptible CMS and Restorer Lines. The hybrids based on shoot flyresistant CMS and Restorer Lines were glossy and trichomed and had lower proportion of plants with eggs (78.5% vs. 88.4 to 93.3%) and deadhearts (40.8% vs. 60.8 to 75.3%) than the hybrids based on other cross combinations, suggesting that resistance is required in both CMS and Restorer Lines for obtaining shoot fly-resistant hybrids. Proportional contributions of CMS Lines for oviposition, deadhearts, leaf glossiness, and recovery resistance were greater than those of the Restorer Lines. The general (GCA) and specific combining ability (SCA) estimates suggested that inheritance for oviposition nonpreference, deadhearts, recovery resistance, and the morphological traits associated with resistance or susceptibility to A. soccata were governed by additive-type of gene action. The SCA effects and heterosis estimates indicated that heterosis breeding would not be rewarding in breeding for resistance to shoot fly.
Amit Kumar - One of the best experts on this subject based on the ideXlab platform.
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marker assisted identification of Restorer gene s in iso cytoplasmic Restorer Lines of wa cytoplasm in rice and assessment of their fertility restoration potential across environments
Physiology and Molecular Biology of Plants, 2017Co-Authors: Amit Kumar, Prolay Kumar Bhowmick, Vikram Jeet Singh, Manoj Malik, Ambrish Gupta, Rakesh Seth, M Nagarajan, Subbaiyan Gopala Krishnan, Ashok Kumar SinghAbstract:Iso-cytoplasmic Restorers possess the same male sterile cytoplasm as the cytoplasmic male sterile (CMS) Lines, thereby minimizing the potential cyto-nuclear conflict in the hybrids. Restoration of fertility of the wild abortive CMS is governed by two major genes namely, Rf3 and Rf4. Therefore, assessing the allelic status of these Restorer genes in the iso-cytoplasmic Restorers using molecular markers will not only help in estimating the efficiency of these genes either alone or in combination, in fertility restoration in the hybrids in different environments, but will also be useful in determining the efficacy of these markers. In the present study, the efficiency of molecular markers in identifying genotypes carrying Restorer allele of the gene(s) Rf3 and Rf4, restoring male fertility of WA cytoplasm in rice was assessed in a set of 100 iso-cytoplasmic rice Restorers using gene linked as well as candidate gene based markers. In order to validate the efficacy of markers in identifying the Restorers, a sub-set of selected 25 iso-cytoplasmic rice Restorers were crossed with four different cytoplasmic male sterile Lines namely, IR 79156A, IR 58025A, Pusa 6A and RTN 12A, and the pollen and spikelet fertility of the F1s were evaluated at three different locations. Marker analysis showed that Rf4 was the predominant fertility Restorer gene in the iso-cytoplasmic Restorers and Rf3 had a synergistic effect on fertility restoration. The efficiency of gene based markers, DRCG-RF4-14 and DRRM-RF3-10 for Rf4 (87%) and Rf3 (84%) genes was higher than respective gene-linked SSR markers RM6100 (80%) and RM3873 (82%). It is concluded that the gene based markers can be effectively used in identifying fertility Restorer Lines obviating the need for making crosses and evaluating the F1s. Though gene based markers are more efficient, there is a need to identify functional polymorphisms which can provide 100% efficiency. Three iso-cytoplasmic Restorers namely, PRR 300, PRR 363 and PRR 396 possessing both Rf4 and Rf3 genes and good fertility restoration have been identified which could be used further in hybrid rice breeding.
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development and evaluation of iso cytoplasmic rice Restorer Lines for different agro morphological traits
Indian Journal of Genetics and Plant Breeding, 2017Co-Authors: Amit Kumar, Prolay Kumar Bhowmick, Gopala S Krishnan, Ashok Kumar SinghAbstract:A set of 390 iso-cytoplasmic Restorer Lines were developed from 25 popular rice hybrids grown in India through pedigree breeding exercising selection for spikelet fertility, yield and extent of panicle exsertion were evaluated for various agromorphological traits. Correlation analysis showed that yield per plant was significantly correlated with number of tillers (0.208), panicle length (0.127) and spikelet fertility (0.134). Principal component analysis indicated that the first four principal components had eigenvalue of > 1.0 and cumulatively explained 74.3% of total variance. Grain characters namely, test weight (0.451), kernel length before cooking (0.418), kernel breadth before cooking (0.136) and spikelet fertility (0.402) contributed positively towards principal component I. Yield per plant showed a positively skewed distribution with panicle length and a nearly linear relationship with spikelet fertility. A core set of 21 genotypes capturing the entire range of phenotype for different traits, was identified from 390 genotypes using advanced M (maximization) strategy and statistically validated. Besides this, promising iso-cytoplasmic Restorer Lines originating from different hybrids were identified for various agromorphological traits. This is the first report on developing iso-cytoplasmic Restorers from popular rice hybrids, which can be used in developing heterotic hybrids when crossed with diverse non-parental CMS Lines.