Study of genetic variation in sesame (Sesamum indicum L.) using agro-morphological traits and ISSR markers

This research was conducted to study the genetic variation among eighteen genotypes of sesame (Sesamum indicum L.) collected from various agro-climatic regions of Iran along with six exotic genotypes from the Asian countries using both agro-morphological and ISSR marker traits. The results showed significant differences among genotypes for all agro-morphological traits and a relatively high genetic coefficient of variation observed for number of fruiting branches per plant, capsules per plant, plant height and seed yield per plant. Cluster analysis based on these traits grouped the genotypes into five separate clusters. Larger inter- than intra cluster distances implies the presence of higher genetic variability between the genotypes of different groups. Genotypes of two clusters with a good amount of genetic divergence and desirable agronomic traits were detected as promising genotypes for hybridization programs. The 13 ISSR primers chosen for molecular analysis revealed 170 bands, of which 130 (76.47%) were polymorphic. The generated dendrogram based on ISSR profiles divided the genotypes into seven groups. A principal coordinate analysis confirmed the results of clustering. The agro-morphological traits and ISSR markers reflected different aspects of genetic variation among the genotypes as revealed by a non significant cophenetic correlation in the Mantel test. Therefore the complementary application of both types of information is recommended to maximize the efficiency of sesame breeding programs. The discordance among diversity patterns and geographical distribution of genotypes found in this investigation implies that the parental lines for hybridization should be selected based on genetic diversity rather than the geographical distribution.     

Study of genetic variation in sesame (<Emphasis Type="Italic">Sesamum indicum</Emphasis> L.) using agro-morphological traits and <Emphasis Type="Italic">ISSR</Emphasis> markers

This research was conducted to study the genetic variation among eighteen genotypes of sesame (Sesamum indicum L.) collected from various agro-climatic regions of Iran along with six exotic genotypes from the Asian countries using both agro-morphological and ISSR marker traits. The results showed significant differences among genotypes for all agro-morphological traits and a relatively high genetic coefficient of variation observed for number of fruiting branches per plant, capsules per plant, plant height and seed yield per plant. Cluster analysis based on these traits grouped the genotypes into five separate clusters. Larger interthan intra cluster distances implies the presence of higher genetic variability between the genotypes of different groups. Genotypes of two clusters with a good amount of genetic divergence and desirable agronomic traits were detected as promising genotypes for hybridization programs. The 13 ISSR primers chosen for molecular analysis revealed 170 bands, of which 130 (76.47%) were polymorphic. The generated dendrogram based on ISSR profiles divided the genotypes into seven groups. A principal coordinate analysis confirmed the results of clustering. The agro-morphological traits and ISSR markers reflected different aspects of genetic variation among the genotypes as revealed by a non significant cophenetic correlation in the Mantel test. Therefore the complementary application of both types of information is recommended to maximize the efficiency of sesame breeding programs. The discordance among diversity patterns and geographical distribution of genotypes found in this investigation implies that the parental lines for hybridization should be selected based on genetic diversity rather than the geographical distribution.     

Association mapping of agro-morphological characters among the global collection of finger millet genotypes using genomic SSR markers

Identification of alleles responsible for various agro-morphological characters is a major concern to further improve the finger millet germplasm. Forty-six genomic SSRs were used for genetic analysis and population structure analysis of a global collection of 190 finger millet genotypes and fifteen agro-morphological characters were evaluated. The overall results showed that Asian genotypes were smaller in height, smaller flag leaf length, less basal tiller number, early flowering and early maturity nature, small ear head length, and smaller in length of longest finger. The 46 SSRs yielded 90 scorable alleles and the polymorphism information content values varied from 0.292 to 0.703 at an average of 0.442. The gene diversity was in the range of 0.355 to 0.750 with an average value of 0.528. The 46 genomic SSR loci grouped the 190 finger millet genotypes into two major clusters based on their geographical origin by the both phylogenetic clustering and population structure analysis by STRUCTURE software. Association mapping of QTLs for 15 agro-morphological characters with 46 genomic SSRs resulted in identification of five markers were linked to QTLs of four traits at a significant threshold (P) level of ≤0.01 and ≤0.001. The QTL for basal tiller number was strongly associated with the locus UGEP81 at a P value of 0.001 by explaining the phenotypic variance (R ²) of 10.8 %. The QTL for days to 50 % flowering was linked by two SSR loci UGEP77 and UGEP90, explained 10 and 8.7 % of R ² respectively at a P value of 0.01. The SSR marker, FM9 found to have strong association to two agro-morphological traits, flag leaf width (P—0.001, R ²—14.1 %) and plant height (P—0.001, R ²—11.2 %). The markers linked to the QTLs for above agro-morphological characters found in the present study can be further used for cloning of the full length gene, fine mapping and their further use in the marker assisted breeding programmes for introgression of alleles into locally well adapted germplasm.     

Genetic diversity in basmati rice (<Emphasis Type="Italic">Oryza sativa</Emphasis> L.) germplasm as revealed by microsatellite (SSR) markers

Genetic diversity among rice genotypes, including 15 indica basmati advance lines and 5 basmati improved varieties were investigated by 28 SSR markers including one indel marker. The SSRs covered all the 12 chromosomes that distributed across the rice genomes. The mean number of alleles per locus was 3.60, showing average number of polymorphism information content was 0.48. A total of 101 alleles were also identified from the microsatellite marker loci. A number of SSR markers were also identified that could be utilized to differentiate between rice genotypes. Pair wise Nei’s genetic distance between rice genotypes ranged from 0.07 to 0.95. The dendrogram based on cluster analysis by using SSR polymorphism that grouped the 20 genotypes of rice in to five clusters based on their genetic similarity. The result could be useful for the identification and selection of the diverse genotypes for the future cross breeding program and development of new rice varieties.     

Morphological and molecular characterization of sweet,grain and forage sorghum (Sorghum bicolor L.) genotypes grown under temperate climatic conditions

Abstract

In the present study, we used 12 genotypes of sorghum originated from different countries (five sweet, four grain and three forage). These different genotypes and types of sorghum were evaluated for the agro-morphological traits that are associated with the estimated sugar and bioethanol yield to estimate their phenotypic diversity. Analysis of variance showed significant differences between different types of sorghum for all the evaluated traits. Sweet sorghum genotypes, however, showed better performance with respect to all studied traits than the other genotypes. A positive significant correlation was observed between plant height, leaf number, leaf area, biomass yield, cane and bagasse yields, and the predicted bioethanol yield. Both, cluster and principal component analysis were performed to group the genotypes according to their agro-morphological and molecular similarity coefficients. For analytical approaches, the Iranian grain and forage genotypes clustered separately from the other genotypes. The clustering patterns obtained from the molecular dominant markers had higher discriminatory power than using morphological characters to separate sweet genotypes from the forage and grain sorghum ones. The results clearly indicated that sweet sorghum can be grown in Germany and maintains its superiority in biomass production and sugar yield over grain and forage sorghum types.     

Molecular profiling in relation to drought tolerance in advance breeding lines of rice using microsatellite markers

Using agro-morphological characters and microsatellite markers, advance breeding lines of rice were discriminated for their ability to tolerate drought stress at reproductive stage. Experimental materials consisting of 17 advance breeding lines and a check were evaluated in randomized block design with three replications under irrigated condition and drought condition created under rainout shelter during three consecutive years. An analysis of variance revealed significant differences among the genotypes for all the ten agro-morphological characters evaluated under both the conditions across the years. Principal component analysis showed the relative importance of root length, number of tillers per plant, number of grains per panicle, harvest index and grain yield per plant among agro-morphological characters and stress tolerance level, stress susceptibility index, stress tolerance index and drought tolerance efficiency among drought tolerance indices as the important classification variables. Relative mean performance in respect of grain yield as well as drought tolerance indices reflected remarkably greater degree of drought tolerance in 11 advance breeding lines and the check, discriminating them from remaining entries under evaluation. Utilizing a panel of 32 microsatellite primers, selective amplification of targeted genomic regions revealed that the primers RM 72, RM 163, RM 212, RM 225, RM 231, RM 302, RM 327, RM 518, RM 521, RM 555, RM 1349, RM 3549 and RM 5443 were highly informative with greater gene diversity and discrimination ability. Hierarchical cluster analysis based on molecular profiles discriminated the entries into five genotypic groups and drought tolerant entries were accommodated into three distinct groups with remarkably greater efficiency (85.7%). Principal coordinate analysis based two dimensional plots of microsatellites dependent genetic profiles displayed a very close correspondence with the genotypic clustering pattern revealed from a perusal of dendrogram. Sequential exclusion of primers in cluster analysis led to identification of RM 212, RM 231, RM 324, RM 431, RM 521, RM 3549 and RM 6374 as the most useful primers for discrimination of drought tolerant and susceptible lines of rice. Molecular profiling based on these markers can be utilized as efficient tools for discrimination and identification of drought tolerant lines.

     

Genetic diversity in basmati rice (Oryza sativa L.) germplasm as revealed by microsatellite (SSR) markers

Genetic diversity among rice genotypes, including 15 indica basmati advance lines and 5 basmati improved varieties were investigated by 28 SSR markets including one indel marker. The SSRs covered all the 12 chromosomes that distributed across the rice genomes. The mean number of alleles per locus was 3.60, showing average number of polymorphism information content was 0.48. A total of 101 alleles were also identified from the microsatellite marker loci. A number of SSR markers were also identified that could be utilized to differentiate between rice genotypes. Pair wise Nei,s genetic distance between rice genotypes ranged from 0.07 to 0.95. The dendrogram based on cluster analysis by using SSR polymorphism that grouped the 20 genotypes of rice in to five clusters based on their genetic similarity. The result could be useful for the identification and selection of the diverse genotypes for the future cross breeding program and development of new rice varieties.     

Genetic diversity in wild sweet cherries (Prunus avium) in Turkey revealed by SSR markers

Wild sweet cherry (Prunus avium) trees are abundant in the northern part of Turkey, including the Coruh Valley. We analyzed 18 wild sweet cherry genotypes collected from diverse environments in the upper Coruh Valley in Turkey to determine genetic variation, using 10 SSR primers. These SSR primers generated 46 alleles; the number of alleles per primer ranged from 3 to 7, with a mean of 4.6. The primer PS12A02 gave the highest number of polymorphic bands (N = 7), while CPSCT010, UDAp-401 and UDAp-404 gave the lowest number (N = 3). Seven groups were separated in the dendrogram, although most of the genotypes did not cluster according to phenological and morphological traits. This level of genetic diversity in these wild sweet cherry genotypes is very high and therefore these trees would be useful as breeders for crosses between cultivated sweet cherry and wild genotypes.     

Comparative evaluation of genetic diversity using RAPD,SSR and cytochrome P450 gene based markers with respect to calcium content in finger millet (<Emphasis Type="Italic">Eleusine coracana</Emphasis> L. Gaertn.)

Genetic relationships among 52 Eleusine coracana (finger millet) genotypes collected from different districts of Uttarakhand were investigated by using randomly amplified polymorphic DNA (RAPD), simple sequence repeat (SSR) and cytochrome P450 gene based markers. A total of 18 RAPD primers, 10 SSR primers, and 10 pairs of cytochrome P450 gene based markers, respectively, revealed 49.4%, 50.2% and 58.7% polymorphism in 52 genotypes of E. coracana. Mean polymorphic information content (PIC) for each of these marker systems (0.351 for RAPD, 0.505 for SSR and 0.406 for cyt P450 gene based markers) suggested that all the marker systems were effective in determining polymorphisms. Pair-wise similarity index values ranged from 0.011 to 0.999 (RAPD), 0.010 to 0.999 (SSR) and 0.001 to 0.998 (cyt P450 gene based markers) and mean similarity index value of 0.505, 0.504 and 0.499, respectively. The dendrogram developed by RAPD, SSR and cytochrome P450 gene based primers analyses revealed that the genotypes are grouped in different clusters according to high calcium (300–450 mg/100 g), medium calcium (200–300 mg/100 g) and low calcium (100–200 mg/100 g). Mantel test employed for detection of goodness of fit established cophenetic correlation values above 0.95 for all the three marker systems. The dendrograms and principal coordinate analysis (PCA) plots derived from the binary data matrices of the three marker systems are highly concordant. High bootstrap values were obtained at major nodes of phenograms through WINBOOT software. Comparison of RAPD, SSR and cytochrome P450 gene based markers, in terms of the quality of data output, indicated that SSRs and cyt P450 gene based markers are particularly promising for the analysis of plant genome diversity. The genotypes of finger millet collected from different districts of Uttarakhand constitute a wide genetic base and clustered according to calcium contents. The identified genotypes could be used in breeding programmes and amajor input into conservation biology of cereal crops.     

Profiling of selected indigenous rice (Oryza sativa L.) landraces of Rarh Bengal in relation to osmotic stress tolerance

A total of ten rare indigenous rice landraces of West Bengal were screened for germination potential and seedling growth under varying concentrations of sodium chloride (NaCl) and polyethylene glycol (PEG) solutions as osmotic stress inducing agents. Among the studied rice landraces Kelas and Bhut Moori showed highest degree of tolerance to induced osmotic stresses. Proline content of the studied lines was also determined. Genetic relationship among the studied rice landraces was assessed with 22 previously reported osmotic stress tolerance linked Simple Sequence Repeat (SSR) markers. The identified allelic variants in form of amplified products size (molecular weight) for each SSR marker were documented to find out allele mining set for the linked markers of the studied genotypes in relation to osmotic stress tolerance. A Microsatellite Panel was constructed for the different allelic forms (size of amplified products) of each used marker. Among 22 SSR markers, ten showed unique alleles in form of single specific amplified product for the studied four genotypes which can be used for varietal identification. Genetic relationship among the studied rice lines was determined and a dendrogram was constructed to reveal their genetic inter-relationship. Polymorphism Information Content (PIC) for each used marker was also calculated for the studied rice lines.     

Cross-genera amplification of Cajanus spp. specific SSR markers in Clitoria ternatea (L.) and their application in genetic diversity studies

Clitoria ternatea (L.) is a medicinal leguminous plant and is cultivated to cater the need of herbal industries and asthetic purposes. The unavailability of steady molecular marker impedes the genetic improvement of C. ternatea. In the present study, transferability of 98 pairs of Cajanus spp. specific SSR primers were assessed among 14 genotypes of C. ternatea, varied for their flower color, floral architecture and bio-metabolite (taraxerol and delphinidin) content, and out of them 43 had successfully amplified the fragments. Among them, 36 pairs of primers showed 100% transferability, whereas rest seven varied from 42.86 to 92.85% transferability. The transferable 43 pairs of SSR primers generated 196 alleles across the 14 genotypes and the AMOVA analysis showed moderate genetic variation (55.1%) among the genotypes of C. ternatea, which was also reinforced by Nei’s genetic distance and gene identity estimates derived haplotype matrix. Similarly, both the principal coordinate analysis and dendrogram grouped these 14 genotypes of C. ternatea into two major clusters based on SSR allele distribution and frequency, and the clustering pattern is in accordance with petal color but in contrast to floral architecture. MCheza based outlier analysis revealed 16 alleles for balancing selection, which are putatively involved in the maintenance of genetic polymorphism in C. ternatea. Moreover, the estimates of molecular diversity and bio-metabolite content revealed the possible use of these genotypes in future breeding programme of this species.Electronic supplementary materialThe online version of this article (10.1007/s12298-020-00907-x) contains supplementary material, which is available to authorized users.     

Water stress mediated root trait dynamics and identification of microsatellite markers associated with root traits in rice ( Oryza sativa L.)

To identify microsatellite markers associated with root traits for drought tolerance in rice (Oryza sativa L.) a study was conducted at Department of Plant Physiology, College of Agriculture, Trivandrum, Kerala Agricultural University. A set of thirty-five rice genotypes were exposed to water stress and evaluated for physio-morphological components as indices of water stress tolerance. Observations were made on leaf rolling score and root traits, especially the root length, root dry weight, root volume and root shoot ratio at booting stage. As of the data obtained, ten tolerant and ten susceptible varieties were selected for bulk line analysis to identify the DNA markers linked with target gene conferring drought tolerance. Out of 150 SSR primers screened, RM474 showed polymorphism between the tolerant and susceptible bulks. Individual genotypes of the bulks also showed the same product size of the respective tolerant and susceptible bulks.     

Induced mutagenesis in Jatropha curcas L. using gamma rays and detection of DNA polymorphism through RAPD marker

The aim of this study is to examine the effect of different doses (control, 5, 10, 15, 20 and 25 Kr) of gamma irradiation on seed germination, flowering, fruit and seed traits of Jatropha curcas and to identify DNA polymorphism among the mutants through a Randomly Amplified Polymorphic DNA (RAPD) marker analysis. The improved agronomic traits such as flowering, fruits and seeds were recorded in 5 Kr dose and seed germination percentage in 10 Kr dose treated plants, while corresponding parameters were reduced significantly (P>0.05) in 25 Kr dose gamma rays treated plants when compared to that of control. All the twenty-three random primers used except six primers, namely OPAW16, OPAK07, OPAK15, OPS01, OPAK20 and OPAL09 were showed polymorphic bands. The primers: OPAW16, OPAK07, OPAK15, OPS01, OPAK20 and OPAL09 produced only one band each across the six mutants, while the primers: OPU13, OPAB 15, OPF01 and OPAB11 were produced with maximum number of bands (8). The number of amplicons varied from 1 to 8 with an average of 3.9 bands, of which 2.3 were polymorphic. The percentage of polymorphism per primer ranged from 0 to 100 with an average of 55.16%. The Jaccard's coefficients of dissimilarity varied from 0.324 to 0.397, indicative of the level of genetic variation among the mutants studied. The maximum dissimilarity value (0.397) was observed in 5 Kr mutant while the minimum value (0.250) was observed in 20 Kr mutant when compared to that of control. In a dendrogram constructed based on genetic similarity coefficients, the mutants were grouped into three main clusters; (a) control, 10, 15 and 20 Kr dose mutants clustered together, (b) 25 Kr dose grouped alone, (c) 5 Kr dose also grouped alone. The mutants showing the differences in morphological traits showed DNA polymorphism in PCR profile amplified by RAPD marker. It is concluded that DNA polymorphism detected by RAPD analysis offered a useful molecular marker for the identification of mutants in gamma radiation treated plants.     

SSR based genetic diversity of pigmented and aromatic rice (<Emphasis Type="Italic">Oryza sativa</Emphasis> L.) genotypes of the western Himalayan region of India

A set of 24 of SSR markers were used to estimate the genetic diversity in 16 rice genotypes found in Western Himalayas of Kashmir and Himachal Pradesh, India. The level of polymorphism among the genotypes of rice was evaluated from the number of alleles and PIC value for each of the 24 SSR loci. A total of 68 alleles were detected across the 16 genotypes through the use of these 24 SSR markers The number of alleles per locus generated varied from 2 (RM 338, RM 452, RM 171) to 6 (RM 585, RM 249, RM 481, RM 162). The PIC values varied from 0.36 (RM 1) to 0.86 (RM 249) with an average of 0.62 per locus. Based on information generated, the genotypes got separated in six different clusters. Cluster 1 comprised of 4 genotypes viz; Zag 1, Zag 13, Pusa sugandh 3, and Zag 14, separated from each other at a similarity value of 0.40. Cluster second comprised of 3 landraces viz; Zag 2. Zag 4 and Zag10 separated from each other at a similarity value of 0.45. Cluster third comprised of 3 genotypes viz; Grey rice, Mushk budji and Kamad separated from each other at a similarity value of 0.46. Cluster fourth had 2 landraces viz; Kawa kreed and Loual anzul, and was not sub clustered. Fifth cluster had 3 genotypes viz; Zag 12, Purple rice and Jhelum separated from each other at a similarity value of 0.28. Cluster 6 comprised of a single popular variety i.e. Shalimar rice 1 with independent lineage.     

Analysis of the genetic diversity of garlic (Allium sativum L.) by simple sequence repeat and inter simple sequence repeat analysis and agro-morphological traits

The genetic diversity of 39 garlic accessions was investigated using eight simple sequence repeat (SSR) primer combinations and 17 inter-simple sequence repeat (ISSR) primer combinations. A total of 109 polymorphic loci were detected among these accessions, with an average of 4.63 polymorphic loci per SSR primer combination and 4.29 polymorphic loci per ISSR primer combination. The mean effective number of alleles, the mean Nei's genetic diversity, and the mean Shannon's information index for SSR were 1.4799, 0.2870, and 0.4378, respectively; and those for ISSR were 1.4847, 0.2898 and 0.4415, respectively. Cluster analysis, using the unweighted pair-group method with arithmetic averages (UPGMA) based on the allele frequency data, classified the accessions into three groups. The results of principal component analysis (PCA) were consistent with those of the cluster analysis. PCA showed that each of these three groups exhibited significant variation in agro-morphological traits. These findings suggest that the eight SSR and 17 ISSR primers identified could define valuable markers for genetic diversity for use by plant breeders.     

Selection of parents for crossing based on genotyping and phenotyping for stripe rust (<Emphasis Type="Italic">Puccinia striiformis</Emphasis>) resistance and agronomic traits in bread wheat breeding

Bread wheat (Triticum aestivum L.) germplasm consisting of 45 genotypes were clustered phenotypically using ten morphological traits and Area Under Disease Progress Curve (AUDPC) as measure of stripe rust resistance. The clustering was ratified by using twenty three molecular markers (SSR, EST and STS) linked to stripe rust (Puccinia striiformis f. sp. tritici) resistant QTLs. The aim was to asses the extent of genetic variability among the genotypes in order to select the parents for crossing between the resistant and susceptible genotypes with respect to stripe rust. The Euclidian dissimilarity values resulted from phenotypic data regarding morphological traits and AUDPC were used to construct a dendrogram for clustering the accessions. Using un-weighted pair group method with arithmetic means, another dendrogram resulted from the similarity coefficient values was used to distinguish the genotypes with respect to stripe rust. Clustering based on phenotypic data produced two major groups and five clusters (with Euclidian dissimilarity ranging from 2.44 to 16.16) whereas genotypic data yielded two major groups and four clusters (with percent similarity coefficient values ranging from 0.1 to 46.0) to separate the gene pool into highly resistant, resistant, moderately resistant, moderately susceptible and susceptible genotypes. With few exceptions, the outcome of both type of clustering was almost similar and resistant as well as susceptible genotypes came in the same clusters of molecular genotyping as yielded by phenotypic clustering. As a result seven genotypes (Bakhtawar-92, Frontana, Saleem 2000, Tatara, Inqilab-91, Fakhre Sarhad and Karwan) of diverse genetic background were selected for pyramiding stripe rust lesistant genes as well as some other agronomic traits after hybridization.     

Molecular characterization of intra-population variability of <Emphasis Type="Italic">Jatropha curcas</Emphasis> L. using DNA based molecular markers

Jatropha curcas L. (Euphorbiaceae) has acquired a great importance as a renewable source of energy with a number of environmental benefits. Very few attempts were made to understand the extent of genetic diversity of J. curcas germplasm. In the present study, efforts were made to analyze the genetic diversity among the elite germplasms of J. curcas, selected on the basis of their performance in field using random amplified polymorphic DNA (RAPD), amplified fragment length polymorphism (AFLP) and simple sequence repeats (SSR). The plants were selected on the basis of height, canopy circumference, number of seeds per fruit, weight of 100 seeds, seed yield in grams per plant and oil content. Out of 250 RAPD (with 26 primers), 822 AFLP (with 17 primers) and 19 SSR band classes, 141, 346 and 7 were found to be polymorphic, respectively. The percentage polymorphism among the selected germplasms using RAPD, AFLP and SSR was found to be 56.43, 57.9, and 36.84, respectively. The Jaccard’s similarity coefficient was found 0.91, 0.90 and 0.91 through RAPD, AFLP and SSR marker systems, respectively. Principle component analysis (PCA) and dendrogarm analysis of genetic relationship among the germplasm using RAPD, AFLP and SSR data showed a good correlation for individual markers. The germplasm JCC-11, 12, 13, 14 and 15 whose yield found to be high were clustered together in dendrogram and PCA analysis though JCC11 is geographically distinct from others. In overall analysis JCC6 (in RAPD), JCC8 (in AFLP) and JCC 6 and JCC10 (in SSR) were found genetically diverse. Characterization of geographically distinct and genetically diverse germplasms with varied yield characters is an important step in marker assisted selection (MAS) and it can be useful for breeding programs and QTL mapping.     

Selection of parents for crossing based on genotyping and phenotyping for stripe rust (Puccinia striiformis) resistance and agronomic traits in bread wheat breeding

Bread wheat (Triticum aestivum L.) germplasm consisting of 45 genotypes were clustered phenotypically using ten morphological traits and Area Under Disease Progress Curve (AUDPC) as measure of stripe rust resistance. The clustering was ratified by using twenty three molecular markers (SSR, EST and STS) linked to stripe rust (Puccinia striiformis f. sp. tritici) resistant QTLs. The aim was to asses the extent of genetic variability among the genotypes in order to select the parents for crossing between the resistant and susceptible genotypes with respect to stripe rust. The Euclidian dissimilarity values resulted from phenotypic data regarding morphological traits and AUDPC were used to construct a dendrogram for clustering the accessions. Using un-weighted pair group method with arithmetic means, another dendrogram resulted from the similarity coefficient values was used to distinguish the genotypes with respect to stripe rust. Clustering based on phenotypic data produced two major groups and five clusters (with Euclidian dissimilarity ranging from 244 to 16.16) whereas genotypic data yielded two major groups and four clusters (with percent similarity coefficient values ranging from 0.1 to 46.0) to separate the gene pool into highly resistant, resistant, moderately resistant, moderately susceptible and susceptible genotypes. With few exceptions, the outcome of both type of clustering was almost similar and resistant as well as susceptible genotypes came in the same clusters of molecular genotyping as yielded by phenotypic clustering. As a result seven genotypes (Bakhtawar-92, Frontana, Saleem 2000, Tatara, Inqilab-91, Fakhre Sarhad and Karwan) of diverse genetic background were selected for pyramiding stripe rust resistant genes as well as some other agronomic traits after hybridization.     

Use of SSR,RAPD markers and protein profiles based analysis to differentiate <Emphasis Type="Italic">Eleusine coracana</Emphasis> genotypes differing in their protein content

Fifty-two genotypes of Eleusine coracana collected from Uttarakhand hills were subjected to simple sequence repeat (SSR), random amplified polymorphic DNA (RAPD)-PCR and protein profiling analysis to investigate the variation in protein content. The main objective of the present study was to detect variability among E. coracana and also assess the discriminating ability of these three molecular methods. A total of 21 RAPD and 24 SSR primers were assayed for their specificity in detecting genetic variability in E. coracana, of which 20 RAPD and 21 SSR primers were highly reproducible and were found suitable for use in PCR analysis. Assessing genetic diversity among E. coracana genotypes by RAPD-PCR using 20 polymorphic primers yielded 56 different RAPD markers which clustered the genotypes into different groups on the basis of protein content. Similarly, SSR-PCR with 21 polymorphic primers clustered the genotypes into different groups. On the other hand, biochemical typing of E. coracana using whole seed proteins generated profiles that showed no major difference indicating the technique to be not useful in typing genotypes of this crop. However, a few of the genotypes showed the presence of a unique band of 32 kDa that needs to be further investigated to understand the role of the protein from nutritional point of view, if any. In the present study, significant negative correlation (r = −0.69*) was found between the protein and calcium content of finger millet genotypes. Sodium Dodecyl Sulphate Polyacrylamide Gel Electrophoresis based seed storage proteins generated profiles showed no major differences in banding pattern among 52 finger millet genotypes while quantitative estimation of seed storage protein fractions using Lowry method revealed that glutelin was highest followed by prolamin, globulin and albumin.     

Genetic diversity among mulberry genotypes from seven countries

Mulberry (Morus alba) is an economically and ecologically important, widespread woody plant. It has served human beings for over hundreds of years, and it is still widely used in pharmaceuticals, food industry and farming nowadays. Using modern techniques, deeper understanding in classification and conservation resources of mulberry leads to higher-efficiency hybrids among populations. Genetic polymorphisms among 42 mulberry genotypes from seven countries over Asia and South America were detected using 17 inter simple sequence repeat (ISSR) primers. A dendrogram was constructed using the similarity matrix among genotypes and a principal component analysis (PCA) was carried out to further identify and cluster the mulberry genotypes. In the 42 genotypes, 175 distinct bands were displayed, among which 169 were polymorphic bands (96.57%). The polymorphic information content of 17 ISSR primers ranged from 0.2921 to 0.3746 with the mean of 0.3494. And Nei’s index and Shanon’s information index averaged 0.116 and 0.174, respectively, indicating low diversity of mulberry. For further study, cluster analysis and PCA were carried out and the results were similar. 42 genotypes were grouped, showing some hybridized combinations. Additionally, a connection between mulberry diseases and their genotypes was noted, which indicates possible application for ISSR in studying disease resistance of mulberry.