RAPD Analysis of Indian Isolates of Rice Sheath Blight Fungus Rhizoctonia solani

Rice sheath blight fungus Rhizoctonia solani has a wide host range and is highly variable in pathogenecity, sclerotial production and cultural characteristics. In India, breeding for sheath blight resistant cultivars has been a priority area of research. However, lack of adequate information about the genetic variability of the fungal populations occurring in India, non-availability of appropriate markers and the non-availability of resistant donors are some of the limiting factors to achieve this objective. To assess the genetic variability in sheath blight fungus, 18 isolates collected from different rice growing regions of India were analyzed by using random amplified polymorphic DNA (RAPD) markers.The similarity values of RAPD profiles ranged from 0.41 to 0.85 with an average of 0.66 among all the isolates. The percentage polymorphism detected per primer varied from 79.2 to 100%. All the primers could be used to fingerprint the individual isolates. The cluster analysis using unweighted paired group method with arithmetic averages could distinguish between R. solani isolates as well as the virulent and avirulent isolates on rice.     

Pathogenic and molecular characterisations of pigeonpea wilt pathogen Fusarium udum

Thirty two pathogenic isolates of Fusarium udum from different pigeonpea growing areas in India were studied for pathogenic and molecular variability. Pathogenic variability was tested on 12 pigeonpea differential genotypes, which revealed prevalence of five variants in F. udum. The amount of genetic variation was evaluated by Polymerase Chain Reaction (PCR) amplification with 20 random amplified polymorphic DNA (RAPD) markers and nine microsatellite markers. All amplifications revealed scorable polymorphisms among the isolates, and a total of 137 polymorphic fragments were scored for the RAPD markers and 16 alleles for the simple sequence repeat (SSR) markers. RAPD primers showed 86% polymorphism. Genetic similarity was calculated using Jaccard's similarity coefficient and cluster analysis was used to generate a dendrogram showing relationships between them. Isolates could be grouped into three subpopulations based on molecular analysis. Results indicated that there is high genetic variability among a subpopulation of F. udum as identified by RAPD and SSR markers and pathogenicity on differential genotypes.     

ERIC and REP-PCR Banding Patterns and Sequence Analysis of the Internal Transcribed Spacer of rDNA of Stemphylium solani Isolates from Cotton

The genetic diversity of the Stemphylium solani isolates from cotton was assessed by Enterobacterial Repetitive Intergenic Consensus (ERIC) and Repetitive Extragenic Palindromes (REP)-PCR fingerprinting. Twenty eight monosporic isolates of S. solani from cotton were used along with five isolates from tomato and one isolate of Alternaria macrospora from cotton for comparison. The dendrogram obtained revealed clear differences between the cotton and tomato isolates as well as between the tomato isolates from different geographic regions. The genetic relationships among S. solani isolates were also analyzed by sequencing the internal transcribed spacer (ITS) region of four isolates representing the three ERIC and REP groups. The tomato isolate from the State of S?o Paulo showed a distinct ITS sequence from that of the cotton isolates and tomato isolate from the State of Goiás, giving evidence that it belongs to a different genotype of S. solani. This is the first report of the entire sequence of the ITS1-5.8S-ITS2 regions of S. solani.     

A Comparative Analysis of ISSR and RAPD Markers for Study of Genetic Diversity in Shisham (<Emphasis Type="Italic">Dalbergia sissoo</Emphasis>)

Shisham (Dalbergia sissoo) is one of the most preferred timber tree species of South Asia. Two DNA-based molecular marker techniques, intersimple sequence repeat (ISSR) and random amplified polymorphism DNA (RAPD), were compared to study the genetic diversity in this species. A total of 30 polymorphic primers (15 ISSR and 15 random) were used. Amplification of genomic DNA of 22 genotypes, using ISSR analysis, yielded 117 fragments, of which 64 were polymorphic. Number of amplified fragments with ISSR primers ranged from five to ten and varied in size from 180 to 1,900 bp. Percentage polymorphism ranged from 0 to 87.5. The 15 RAPD primers produced 144 bands across 22 genotypes, of which 84 were polymorphic. The number of amplified bands varied from five to 13, with size range from 180 to 2,400 bp. Percentage polymorphism ranged from 0 to 100, with an average of 58.3 across. RAPD markers were relatively more efficient than the ISSR assay. The mental test between two Jaccard’s similarity matrices gave r ≥ 0.90, showing very good fit correlation in between ISSR- and RAPD-based similarities. Clustering of isolates remained more or less the same in RAPD and combined data of RAPD and ISSR. The similarity coefficient ranged from 0.734 to 0.939, 0.563 to 0.946, and 0.648 to 0.920 with ISSR, RAPD, and combined dendrogram, respectively.     

Detection of genetic variability in various isolates of cattle tick, <Emphasis Type="Italic">Boophilus microplus</Emphasis> from Tamil Nadu,India using PCR-RAPD analysis

The genomic DNA from ten isolates of the cattle tick, Boophilus microplus collected in and around Chennai, India, was analyzed by random amplified polymorphic DNA (RAPD) using PCR. Selected five random primers were used for the study of genetic variability among different isolates of B. microplus. A high degree of genetic polymorphism with a different pattern of RAPD profiles for each tick isolate was detected with all these random primers. This variability was also confirmed by similarity coefficient values and dendrogram which were performed using mean RAPD profiles for all the primers between various isolates of ticks. The findings suggest the existence of a complex genotypic diversity of the tick B. microplus in an endemic region such as Chennai.     

Genetic diversity of <Emphasis Type="Italic">Macrophomina phaseolina</Emphasis> isolates from certain agro-climatic regions of India by using RAPD markers

Genetic diversity analysis of Macrophomina phaseolina isolates obtained from different host range and diverse geographical locations in India was carried out using RAPD fingerprinting. Of the thirteen 10-mer random primers used, primer OPB-08 gave the maximum polymorphism and the UPGMA clustering could separate 50 isolates in to ten groups at more than 65% similarity level. The ten clusters correlated well with the geographical locations with exceptions for isolates obtained from Eastern and Western Ghats. There was a segregation of isolates from these two geographical locations in to two clusters thus, distributing 10 genotypes in to eight geographical locations. All the isolates M. phaseolina irrespective of their host and geographical origin, exhibited two representative monomorphic bands at 250 bp and 1 kb, presence of these bands suggests that isolates might have evolved from a common ancestor but due to geographical isolation fallowed by natural selection and genetic drift might have segregated in to subpopulations. Genetic similarity in the pathogenic population reflects the dispersal of single lineage in all locations in India.     

Comparison of RAPD and ISSR markers for assessment of genetic diversity among endangered rare Dalbergia oliveri (Fabaceae) genotypes in Vietnam

Dalbergia oliveri is a leguminous tree of the Fabaceae family. This species is popular and valuable in Vietnam and is currently listed on the Vietnam Red List and on the IUCN Red List as endangered. Two PCR techniques using RAPD and inter-simple sequence repeat (ISSR) markers were used to make a comparative analysis of genetic diversity in this species. Fifty-six polymorphic primers (29 RAPD and 27 ISSR) were used. The RAPD primers produced 63 bands across 35 genotypes, of which 24 were polymorphic. The number of amplified bands varied from one to four, with a size range from 250 to 1400 bp. The percentage polymorphism ranged from 0 to 75. Amplification of genomic DNA of the 35 genotypes, using ISSR analysis, yielded 104 fragments, of which 63 were polymorphic. The number of amplified fragments using ISSR primers ranged from one to nine and varied in size from 250 to 1500 bp. The percentage polymorphism ranged from 0 to 100. ISSR markers were relatively more efficient than RAPDs. The mental test between two Jaccard's similarity matrices gave r ≥0.802, showing good fit correlation between ISSRs and RAPDs. Clustering of isolates remained more or less the same for RAPDs compared to combined RAPD and ISSR data. The similarity coefficient ranged from 0.785 to 1.000, 0.698 to 0.956 and 0.752 to 0.964 with RAPD, ISSR, and the combined RAPD-ISSR dendrogram, respectively.     

Genetic variability and relationships among thirty genotypes of finger millet (Eleusine coracana L. Gaertn.) using RAPD markers

Ragi or finger millet (Eleusine coracana L.) is an important crop used for food, forage, and industrial products. It is distributed in tropical and temperate regions of the world. The germplasm identification and characterization is an important link between the conservation and utilization of plant genetic resources. Traditionally, species or varieties identification has relied on morphological characters like growth habit, leaf architecture or floral morphology. Investigation through RAPD (random amplified polymorphic DNA) markers was undertaken for identification and determination of the genetic variation among thirty genotypes of ragi of the family Poaceae. Thirteen selected decamer primers were used for genetic analysis. A total of 124 distinct DNA fragments ranging from 300-3000 bp was amplified by using selected random RAPD marker. The genetic similarity was evaluated on the basis of the presence or absence of bands. Cluster analysis was made by the similarity coefficient. It indicated that the 30 genotypes of ragi form two major clusters, first, a major cluster having only one genotype, i. e. Dibyasinha and a second major cluster having twenty-nine genotypes. The second major cluster again subdivides into two minor clusters. A first minor cluster has only three varieties, i. e. Neelachal, OEB-56 and Chilika. The genotypes Neelachal and OEB-56 exhibit a 86% similarity with each other and 80% similarity with Chilika. A second minor cluster has 26 genotypes and is divided into two sub-minor clusters. The first sub-minor cluster has only one genotype (VL-322). The second sub-minor cluster again subdivides into two groups. One group has one genotype and the second group again is divided into two sub-groups, one with 13 genotypes and the other with 11 genotypes. The highest similarity coefficient was detected in a genotype collected from southern India and the least from northern India. The genotypes of finger millet collected from diverse agroclimatic regions of India constitute a wide genetic base. This is helpful in breeding programs and a major input into conservation biology of cereal crop.     

Molecular diversity of Fusarium oxysporum causing rot diseases of vanilla in south India

Incidence of root, stem and beans rot of vanilla (Vanilla planifolia Andrews) caused by Fusarium oxysporum Schlecht was surveyed in vanilla growing areas of south India during December 2008. The incidence of the disease varied from 1 to 100% in different locations. A total of 60 isolates of F. oxysporum were obtained from diseased samples, and nine morphologically different isolates were taken for molecular characterization using Randomly Amplified Polymorphic DNA (RAPD) markers to study the genetic variability if any, among them. PCR amplification of total genomic DNA with random oligonucleotide primers generated unique banding patterns depending upon primers and isolates. Nine oligonucleotide primers were selected for the RAPD assays, which resulted in 384 bands for nine isolates of F. oxysporum. The number of bands obtained was entered into a NTSYS and the results showed that the variability among the pathogen isolates was moderate. The nine isolates studied were grouped into single major cluster at 0.66 similarity index. Hence, it is inferred that F. oxysporum infecting vanilla in south India consists of a single clonal lineage with a moderate level of genetic diversification.     

Comparison of RAPD and RFLP genetic markers in determining genetic similarity among Brassica oleracea L. genotypes

Genetic similarity among 45 Brassica Oleracea genotypes was compared using two molecular markers, random amplified polymorphic DNA (RAPD) and restriction fragment length polymorphisms (RFLPs). The genotypes included 37 broccolis (var. italica), five cauliflowers (var. botrytis) and three cabbages (var. capitata) which represented a wide range of commercially-available germplasm, and included open-pollinated cultivars, commercial hybrids, and inbred parents of hybrid cultivars. Fifty-six polymorphic RFLP bands and 181 polymorphic RAPD bands were generated using 15 random cDNA probes and 62 10-mer primers, respectively. The objectives were to compare RFLP and RAPD markers with regard to their (1) sampling variance, (2) rank correlations of genetic distance among sub-samples, and (3) inheritance. A bootstrap procedure was used to generate 200 random samples of size n (n=2,3,5,... 55) independently from the RAPD and RFLP data sets. The coefficient of variance (CV) was estimated for each sample. Pooled regressions of the coefficient of variance on bootstrap sample size indicated that the rate of decrease in CV with increasing sample size was the same for RFLPs and RAPDs. The rank correlation between the Nei-Li genetic similarity values for all pairs of genotypes (990) based on RFLP and RAPD data was 0.745. Differences were observed between the RFLP and RAPD dendrograms of the 45 genotypes. Overlap in the distributions of rank correlations between independent sub-samples from the RAPD data set, compared to correlations between RFLP and RAPD sub-samples, suggest that observed differences in estimation of genetic similarity between RAPDs and RFLPs is largely due to sampling error rather than due to DNA-based differences in how RAPDs and RFLPs reveal polymorphisms. A crossing algorithm was used to generate hypothetical banding patterns of hybrids based on the genotypes of the parents. The results of this study indicate that RAPDs provide a level of resolution equivalent to RFLPs for detemination of the genetic relationships among genotypes.     

RAPD based genetic diversity among different isolates of <Emphasis Type="Italic">Fusarium oxysporum</Emphasis> f. sp<Emphasis Type="Italic">. lycopersici</Emphasis> and their comparative biocontrol

Fusarium wilt of tomato (Solanum lycopersicum Mill.) caused by Fusarium oxysporum f. sp. lycopersici (Sacc.) W. C. Snyder and H. N. Hans (Fol.), is most serious and versatile pathogen. Chemical control of disease is not satisfactory and biological control is an attractive and potential alternative to the use of chemicals to control fusarium wilt of tomato. No any bioagent is universally effective everywhere therefore, search for potential biocontrol agent is continuous process and mandatory for several and individual ecological niches. In this experiment biocontrol efficacy of five species of Aspergillus and five species of Trichoderma were evaluated in vitro against Fusarium oxysporum f. sp. lycopersici. In both the experiments (dual culture and culture filtrates) T. harzianum was found to be highly effective against the isolates of Fol. followed by A. niger biocontrol potential of A. terreus is least among all the isolates tested. Culture filtrates obtained from A. luchuensis exerted least inhibition of Fol. The most sensitive isolate of Fol. against all the antagonists tested was identified as IIVR-2 (Fol. 9). Inherent diversity among Fol. isolates, from different tomato growing regions in India, was determined using RAPD primers. The genetic similarity coefficients ranged from 0.20 to 0.96, indicating that no any two or more isolates were 100% similar. RAPD profiles revealed up to 20% genetic diversity among ten isolates of Fusarium oxysporum f. sp. lycopersici.     

不同来源鼠李糖乳杆菌的随机扩增多态DNA分析

[目的]建立鼠李糖乳杆菌(Lactobacillus rhamnosus,Lr)菌株之间的分子鉴别方法并分析不同分离株之间的遗传多样性.[方法]从56份采集自中国新疆和田和广西巴马瑶族自治县的长寿老人粪便样本中分离得到的乳酸菌中,经生理生化分析和API 50CHL试验条鉴定,获得10株Lr.对10株Lr分离株和1株Lr标准株ATCC7469进行了随机扩增多态DNA分析,从50条随机引物中筛选到5条在菌株水平上具有鉴别力的引物P14、OPG28、OPG25、P7和P4并建立和优化了Lr菌株RAPD指纹图谱扩增方法.根据RAPD结果计算菌株间的遗传相似系数并进行聚类分析.[结果]获得了清晰稳定的DNA指纹图谱,扩增产物大小在100～2000bp之间,菌株间呈现显著的DNA多态性,不同来源的Lr分离株的遗传相似系数在0.581～0.935之间,在相似系数0.80水平上可以将11株Lr菌株分为5个类群,其中分离自新疆和田的Lr菌株归在类群B和类群C,而分离自广西巴马瑶族自治县的Lr菌株归在类群D和类群E.[结论]应用RAPD方法对Lr菌株进行分子鉴别是可行的,不同来源的Lr之间存在着较大的种内遗传多态性和不同的亲缘关系.     

Biochemical and molecular characteristics of indigenous strains of the entomopathogenic fungus Beauveria bassiana of Central India

Forty-eight isolates of indigenous strains of Beauveria bassiana from various insect hosts collected from Central India were characterised by employing protease zymography and RAPD analysis. Results of protease zymographic profiles were reproducible and significant enough to contribute to the biochemical diversity of this species. RAPD analysis revealed the presence of high level of genetic diversity and indicated that 0-66% significant differences has evolved between these isolates. The sets of amplified bands showing identical pattern to others were grouped at 100% similarity level. A wide range in the value (0.25-1.00) of Jaccard similarity coefficient was observed among all the isolates. The grouping of the indigenous strains, obtained from numerical analysis of these data, appears to be related to the host specificity in B. bassiana. Clear groups were seen for strains isolated from Lepidopteran and Coleopteran insect hosts.     

Chemoraces and habitat specialization of Claviceps purpurea populations

We studied genetic variability of 100 isolates of Claviceps purpurea by using randomly amplified polymorphic DNA (RAPD), an EcoRI restriction site polymorphism in the 5.8S ribosomal DNA (rDNA), the alkaloids produced, and conidial morphology. We identified three groups: (i) group G1 from fields and open meadows (57 isolates), (ii) group G2 from shady or wet habitats (41 isolates), and (iii) group G3 from Spartina anglica from salt marshes (2 isolates). The sclerotia of G1 isolates contained ergotamines and ergotoxines; G2 isolates produced ergosine and ergocristine along with small amounts of ergocryptine; and G3 isolates produced ergocristine and ergocryptine. The conidia of G1 isolates were 5 to 8 microm long, the conidia of G2 isolates were 7 to 10 microm long, and the conidia of G3 isolates were 10 to 12 microm long. Sclerotia of the G2 and G3 isolates floated on water. In the 5.8S rDNA analysis, an EcoRI site was found in G1 and G3 isolates but not in G2 isolates. The host preferences of the groups were not absolute, and there were host genera that were common to both G1 and G2; the presence of members of different groups in the same locality was rare. Without the use of RAPD or rDNA polymorphism, it was not possible to distinguish the three groups solely on the basis of phenotype, host, or habitat. In general, populations of C. purpurea are not host specialized, as previously assumed, but they are habitat specialized, and collecting strategies and toxin risk assessments should be changed to reflect this paradigm shift.     

Detection of molecular variation in the insect pathogenic fungus Metarhizium using RAPD-PCR

Abstract DNA polymorphism among isolates of the insect pathogenic fungus Metarhizium anisopliae and M. flavoviride was investigated by RAPD-PCR. DNA fragments of between 0.3 and 2.7 kb were obtained using eight 10-mer PCR primers of arbitrary nucleotide sequence, and each isolate differed in the size and number of RAPD products, indicating considerable polymorphism. Isolate-specific RAPD fingerprints were used to calculate relative genetic similarity; this differentiated isolates into two major groups, separating nine of the ten isolates of M. anisopliae from the two of M. flavoviride . However, an Australian M. anisopliae isolated from an Orthopteran host exhibited a higher degree of genetic similarity to the M. flavoviride group. M. anisopliae isolates were further segregated into three subgroups which were loosely related to their geographical origins. although considerable polymorphism was observed within these groups. There was no apparent association between genotype and original insect host.     

RAPD cluster analysis and chlorate sensitivity of some Indian isolates of Macrophomina phaseolina from sorghum and their relationships with pathogenicity

Charcoal rot caused by Macrophomina phaseolina is an economically important disease in sorghum grown during the post rainy season in India. Variations in random amplified polymorphic DNA (RAPD) polymorphisms, chlorate sensitivity and pathogenicity were studied among sorghum isolates of M. phaseolina collected from different parts of India. RAPD data based on 14 random primers of Kit A and C (OPA and OPC) on 20 isolates showed a high degree of polymorphism (98.1%) in different isolates. UPGMA dendrogram on RAPD data produced 7 clusters at the level of 37% similarity. Isolates from the same locations showed a tendency to group closer, substantiating closer genetic relatedness. Sorghum infecting Macrophomina isolates showed a mixed response for sensitivity to potassium chlorate (120 mM). Chlorate-resistant isolates were predominant (>65% of the isolates) over sensitive isolates. Chlorate-sensitive isolates were found to be genetically closer among them than the resistant ones. For the first time it was shown that chlorate sensitivity in Macrophomina had some relations with charcoal rot severity in sorghum.     

Morphological, Biochemical and Molecular Characterization of Trichoderma harzianum Isolates for their Efficacy as Biocontrol Agents

The random amplified polymorphic DNA (RAPD) procedure was used to examine the genetic variability among 8 isolates of Trichoderma harzianum , and their ability to antagonize Sclerotium rolfsii using a dual culture assay was correlated with RAPD profiles. Eight oligodeoxynucleotide primers were selected for the RAPD assays, which resulted in 86 bands for 8 isolates of T . harzianum . The data were entered into a binary matrix and a similarity matrix was constructed using the DICE similarity (SD) index. An unweighted pair grouping mathematical averaging (UPGMA) cluster based on SD values was generated using the NTSYS computer program. A mean coefficient of similarity obtained for pairwise comparisons was c. 30% and it showed that the variability among the isolates of T. harzianum was very high. Using the dual culture method in antagonism experiments, the T. harzianum isolates were classified in to antagonism classes. Further, T. harzianum isolates were screened for chitinase and β-1,3-glucanase activity. RAPD was efficient in demonstrating the high intraspecific genetic variation among isolates. The dendrogram did not show the grouping of isolates by their level of antagonism. Relationship among polymorphism existent, the aggressiveness and the origin of isolates were not found.     

Isozyme and PCR-based genotyping of epidemic Phytophthora colocasiae associated with taro leaf blight

The Oomycetous fungus Phytophthora colocasiae causing leaf blight of taro is widely distributed in India. Wide geographic range or sexual recombination provides genetic differentiation within this species. To determine how genetic variation is partitioned in P. colocasiae, 14 isolates were isolated from different regions of India, where the incidence of leaf blight is great. Molecular and biochemical techniques were employed for assessing and exploiting the genetic variability among isolates of P. colocasiae. Seven polymorphic enzyme systems revealed 23 isozyme patterns, each uniquely characterised by the presence or absence of electromorphs. Further, 10 oligodeoxynucleotide primers were selected for random amplified polymorphic DNA (RAPD) assays, which resulted in 123 polymorphic bands for 10 isolates of P. colocasiae. The data were entered into a binary matrix and a similarity matrix was constructed using a DICE similarity (SD) index. A UPGMA cluster based on SD values was generated using a NTSYS computer program. Shannon's index was used to partition genetic diversity. Similarly, isozymes and RAPDs yielded high estimates of genetic variability. Genetic diversity estimates via isozyme and RAPD pattern indicated 78.26% and 100%, respectively, total diversity among populations. This type of genetic variation in P. colocasiae indicates that variation due to asexual and/or possibly infrequent sexual mechanisms is possible and that genetic differentiation has taken place as a result of geographic isolation. The presence of larger than expected RAPD variation in isolates of P. colocasiae and the presence of distinct different zymotypes among these isolates suggests that genetic recombination (or less likely hybridisation) is at least possible in this fungus and that geographic differentiation has taken place. Even isolates obtained from the same habitat have different RAPD patterns, indicating that many populations of this fungus are made up of more than one genet and that few are derived clonally.     

Analysis of Genetic Diversity in Cicer arietinum L Using Random Amplified Polymorphic DNA Markers

PCR-based random amplified polymorphic DNA (RAPD) markers were employed to assess genetic diversity in 23 chickpea genotypes. Forty of the 100 random primers screened revealed polymorphism among the genotypes. Most of the primers revealed single polymorphic band, and only 14.1 2% of the products were polymorphic. Estimates of genetic similarity based on Jaccard’s coefficient ranged from 0.92 to 0.99, indicating narrow genetic variability among the genotypes based on RAPD markers.The 23 chickpea genotypes formed two major clusters in the dendrogram.The low RAPD polymorphism among chickpea genotypes suggests that more number of polymorphic primers need to be analysed to determine genetic relationships. It was observed that RAPD analysis employing 30 polymorphic primers could provide better estimates of genetic relationships in chickpea.     

Determination of genetic diversity among Indian isolates of Rhizoctonia bataticola causing dry root rot of chickpea

Genetic diversity among 27 isolates (23 from chickpea and 4 from other host crops) of Rhizoctonia bataticola representing 11 different states of India was determined by random amplified polymorphic DNA (RAPD), internal transcribed spacer restriction fragment length polymorphism (ITS-RFLP) and ITS sequencing. The isolates showed variability in virulence test. Unweighted paired group method with arithmetic average cluster analysis was used to group the isolates into distinct clusters. The clusters generated by RAPD grouped all the isolates into six categories at 40% genetic similarity. High level of diversity was observed among the isolates of different as well as same state. Some of the RAPD (OPN 4, OPN 12, and OPN 20) markers clearly distinguished majority of the isolates into the area specific groups. The ITS I, 5.8rDNA and ITS II regions of 11 isolates representing different RAPD groups were amplified with primers ITS 1 and ITS 4 and digested with seven restriction enzymes. The restriction enzymes DraI, MboI, RsaI, and AluI were found to be suitable for differentiating the isolates into five categories by showing isolate specific ITS-RFLP patterns. The isolates were variable in their nucleotide sequences of the ITS regions. This is the first study on genetic diversity among chickpea isolates of R. bataticola.