RAPD Analysis Research Articles

Vitrification-cryopreservation of Shoot Tips Excised from Dormant Bulbs in Fritillaria przewalskii Maxim: Assessing Histological lnjuries and Evaluating Genetic Fidelity in Cryo-Derived Plants

Fritillaria przewalskii Maxim. an essential medicinal plant in the Fritillaria genus of the Liliaceae family, is widely used in traditional medicine. This study focused on developing a cryopreservation protocol for F. przewalskii, an endangered and endemic species in China. We aimed to determine if ex vitro bulbs from field-grown F. przewalskii plants could serve a source of shoot tips for cryopreservation. Key factors influencing cryopreservation outcomes were studied using a vitrification-based approach. Prior to cryopreservation, cold hardening and sucrose preculture conditions were optimized. The best results were achieved by hardening bulbs at 4℃ for 3-4 months,followed by surface disinfection and isolation of 2-5mm Shoot tips. The tips were then then precultured on a medium with 0.5M sucrose for 3 days. Cryopreservation steps included a 20-minute loading treatment, 60-minute PVS2 dehydration at room temperature, and storage in liquid nitrogen more than one hour. After thawing, this protocol resulted in 93% shoot survival rate, with tips regenerating into small bulbs within 5 weeks without intermediary callus formation. Histological analysis showed that while cooling and rewarming caused severe bud damage, apical meristem cells are the primary survival sites. Although loading and PVS2 treatment induced cell plasmolysis, it was not lethal. Optimal PVS2 treatment enhanced cellular dehydration resistance, promoting cell viability at ultralow temperature. RAPD analysis of regenepercentaged plants showed no genetic variation, confirming strong genetic stability. The direct use of ex vitro shoot tips provides a straightforward and effective cryopreservation method for F. przewalskii, combining convenience, efficiency, and genetic stability.

Molecular characterisation of virulence genes in bacterial pathogens from daycare centres in Ile-Ife, Nigeria: implications for infection control

BackgroundDaycare centres play a critical role in early childhood development but are high-risk environments for infectious disease transmission due to close physical contact, shared toys, inadequate hygiene, and poor ventilation. These risks are especially concerning in low- and middle-income countries (LMICs) like Nigeria, where resources for infection control may be limited. This study aimed to identify and characterise virulence genes in bacterial isolates from daycare centres in Ile-Ife, Nigeria, to assess infection risks.MethodsBetween November 2017 and July 2019, 233 samples were collected from 76 children, 33 daycare workers, and 124 fomites in 17 daycare centres. The bacterial isolates were analysed using conventional PCR and RAPD analysis to detect the presence of virulence genes. The frequency of crucial virulence genes and the prevalence of each bacterial species were recorded.ResultsKey virulence genes were detected, including fimH in Klebsiella species (22.73% of Gram-negative isolates), algD in Pseudomonas aeruginosa (50%), and icaA and cna in Staphylococcus aureus (16.67%). Staphylococcus aureus was the most prevalent species (35%), followed by Klebsiella (28%) and Pseudomonas aeruginosa (20%).ConclusionThis study highlights the presence of virulent bacterial pathogens in daycare environments, posing a severe infection risk to children. To mitigate these risks, it is essential to implement enhanced infection control measures, such as regular microbial screening, improved hand hygiene practices, and disinfection protocols for fomites. Training programs for daycare workers on hygiene practices and routine monitoring could also significantly reduce infection transmission. These interventions are vital for safeguarding the health of daycare children in Nigeria and similar settings globally.

Isolation and characterization of Streptococcus agalactiae inducing mass mortalities in cultured Nile tilapia (Oreochromis niloticus) with trials for disease control using zinc oxide nanoparticles and ethanolic leaf extracts of some medicinal plants

BackgroundStreptococcus agalactiae (Group B streptococcus, GBS) induces a serious infection that can harm not only aquatic life but also humans and other animals. In a fish farm in southern Egypt, Nile tilapia (Oreochromis niloticus) has developed an epidemic with clinical symptoms resembling piscine streptococcosis.ResultsInitial microscopic inspection of the affected fish brain and kidney indicated the presence of Gram-positive cocci. S. agalactiae was effectively isolated and identified using nucleotide homology of the 16S rRNA and species-specific PCR. The partial 16S rRNA sequence was deposited in the GenBank database at the NCBI and given the accession number MW599202. Genotyping using RAPD analysis indicated that the isolates in the present study belonged to the same genotypes and had the same origin. The challenge test, via immersion (9.2 × 107, 9.2 × 106, and 9.2 × 105 CFU/ml for 1 h) or intraperitoneal injection (4.6 × 107, 4.6 × 106, and 4.6 × 105 CFU/fish), elicited clinical symptoms resembling those of naturally infected fish with a mortality rate as high as 80%. The ability to create a biofilm as one of the pathogen virulence factors was verified. Zinc oxide nanoparticles and the ethanolic leaf extracts of nine medicinal plants demonstrated considerable antibacterial activities against the tested S. agalactiae strain with low minimum bactericidal concentrations (MBC) and minimum inhibitory concentrations (MIC). The ethanolic leaf extracts from Lantana camara and Aberia caffra showed potent antibacterial activity with MBC values of 0.24 and 0.485 mg/ml, and MIC values of 0.12 & 0.24 mg/ml, respectively.ConclusionThis study isolated S. agalactiae from O. niloticus mortalities in a fish farm in Assiut, Egypt. The pathogen persists in fish environments and can escape through biofilm formation, suggesting it cannot be easily eliminated. However, promising findings were obtained with in vitro control employing zinc oxide nanoparticles and medicinal plant extracts. Nevertheless further in vivo research is needed.

Morphological and molecular diversity analysis vis-a-vis phylogenetic correlation among pomegranate (Punica granatum L.) varieties

Abstract Identification of different pomegranate (Punica granatum L.) genotypes using morphological descriptors and further substantiated through molecular means is essential for a breeding program. Characterization using molecular markers has an advantage over its morphological counterpart due to its low expense, quick and reliable results, and the requirement of less sophisticated equipment. In this study, eight different pomegranate cultivars were characterized based on their morphological and molecular characters in sub-tropical regions between 2018 and 2019. Morphological experiments were conducted in a randomized block design replicated thrice for each cultivar, whereas RAPD markers were employed for molecular studies. Principal component analysis revealed significant morphological variation (79.61%) among the cultivars. A high level of polymorphism, similar to PCA, was observed with RAPD analysis (80.49%). Some discrepancies between morphological and molecular results were noted in UPGMA cluster analysis. However, eight primers (total = 41) distinctively separated the Bhagwa variety from others, with the maximum similarity coefficient value (ca. 0.54) and superior fruit quality distinguished in PCA analysis with the maximum mean Euclidean distance (ca. 16). Hence, RAPD markers could be used along with morphological markers for a quick screening of germplasms in further crop improvement programs.

Assessment of genetic diversity of Stephania rotunda Lour. collected in Northern Vietnam using RAPD and ISSR markers

Stephania rotunda Lour. is a valuable traditional medicinal plant that is in danger of extinction. This research aimed to examine the genetic relationship of 32 Stephania rotunda Lour. accessions collected in Vietnam by using RAPD and ISSR markers. 14 RAPD and 14 ISSR primers successfully detected 163 loci of which 133 (80.19%) were polymorphic and a total of 3047 scorable bands were obtained. The 14 RAPD markers produced 1346 scorable bands, 89.63% of which were polymorphic while 14 ISSR primers resulted in 1701 bands, 70.76% of which were polymorphic. The RAPD primers showed a mean PIC of 0.3 and Rp value of 2.28 while the average PIC and Rp indexes for ISSR markers were 0.20 and 1.47, respectively. UPGMA dendrogram obtained from cluster analysis of RAPD and ISSR combined data grouped 32 accessions into five clusters at 76% variation with Jaccard's similarity coefficient varying from 0.586 to 0.951. Moreover, principal component analysis was also used to determine genetic relationships among 32 collected accessions. The results showed high genetic dissimilarity among 32 Stephania rotunda Lour. Correlation analysis between the matrices of similarity coefficient was measured using Mantel’s test. A moderate correlation value (r = 0.543) between RAPD vs ISSR matrices, but the strong correlation value between RAPD and pooled data (r = 0.930) and between ISSR and combined matrices (r = 0.814) were obtained, suggesting a combination of RAPD and ISSR markers appears to be productive in studying the genetic variance in Stephania rotunda Lour. Our results could provide a solid foundation for further conservation management and breeding programs of Stephania rotunda Lour.

Gamma irradiation induced thermotolerance in Metarhizium spp. enhancing biocontrol of Nilapavarta lugens (Stål)

The Brown Planthopper (BPH), Nilaparvata lugens (Stål), is a devastating pest to rice crops in Southeast Asia, primarily due to its resistance to insecticides. As a result, the fungus Metarhizium spp. is used as an alternative control for BPH. However, their efficiency is limited due to delayed infectivity and sensitivity to environmental variables. In this study, two isolates of Metarhizium spp. MLUBN038 and MNMHN031, were induced for thermotolerance and biocontrol potential against Nilapavarta lugens (Stål). A multilocus phylogeny of four protein-coding genes including Beta-tubulin, rpb1, rpb2, and tef has identified the two isolates to be Metarhizium koreanum. Seventy-nine potential thermotolerant mutants were screened from the two isolates. These mutant isolates demonstrated significant tolerance to vegetative heat at 39 °C and enhanced resistance to wet heat stress at 45 °C after exposure for 60 h, outperforming the wild-type (WT) isolates. The mutant isolates also showed increased mycelial growth, conidial germination, and spore production compared to the WT isolates. Two mutant isolates, ML038_Mt 71 and MN031_Mt 46, exhibited the highest efficacy against BPH nymphs (4th-5th instars), resulting in a maximum mortality of 88.82 % and 83.55 %, respectively, compared to the WT (54.07 % and 47.54 %) after 14 days of inoculation in the greenhouse. These two highly virulent mutant isolates presented the lowest LT50 values of 2.88 and 3.72 days at a concentration of 1 × 109 conidia/mL. RAPD analysis revealed genetic diversity between the mutant and WT isolates, indicating distinct diversity profiles and supporting the successful generation of mutant variants. These findings suggest that the use of gamma irradiation and heat stress to induce mutations is crucial for the successful production of thermotolerant mutant isolates. Our results suggest that ML031_Mt 71 and MN031_Mt 46 have potential as effective biocontrol agents.

Genetic relatedness and diversity of Capillaria species infecting bayad (Bagrus bajad) in upper Egypt

BackgroundThis study investigates the genetic characteristics of Capillaria isolates from the infected fish, Bagrus bajad, and their relation to human Capillaria philippinensis using Random Amplified Polymorphic DNA (RAPD-PCR) analysis. Fifteen fish Capillaria were isolated and compared to identified human C. philippinensis using six primers: M-are, M-1, G-7, G-11, G-15, and G-18.ResultsAll six primers successfully amplified DNA, highlighting their efficacy in distinguishing between human and fish Capillaria isolates. The analysis revealed distinctive banding patterns between fish and human isolates, with variations in size and number of DNA fragments. Additionally, genetic similarity analysis showed intriguing patterns of relatedness, with certain pairs exhibiting high similarity percentages. Comparative assessment of RAPD polymorphism demonstrated consistent findings of 100% polymorphism across all primers. The Unweighted Pair Group Method with Arithmetic Mean Algorithm (UPGMA) evaluated the closest relationship between human and fish isolates. These results underscore the utility of RAPD analysis in delineating the genetic diversity among Capillaria isolates from different hosts.ConclusionOverall, this study contributes to our understanding of the genetic variability and relatedness among Capillaria isolates, shedding light on their evolutionary dynamics and zoonotic potential.

Characterization of Alternaria blotch disease of apple in Himachal Pradesh, India: insights on morphology, pathogenicity, and molecular features.

Alternaria blotch disease in Himachal Pradesh, India, caused by Alternaria spp., adversely affects apple cultivars, resulting in reduced fruit size and quality accompanied by premature leaf fall. Sixteen Alternaria isolates from apple growing regions underwent comprehensive analysis including morphology, pathogenicity, and molecular characterization. Variations in conidiophore and conidia dimensions, shapes, and divisions were observed among isolates. Pathogenicity assays revealed differences in incubation periods, latent phases, and disease responses. Molecular characterization via nuclear ITS rDNA and RAPD analysis indicated 99-100% homology with Alternaria alternata, Alternaria mali, and other Alternaria spp., with a close phylogenetic relationship to Chinese isolates. Differentiation of isolates based on origin, cultural characteristics, and morphology was achieved using RAPD markers. The study identifies diverse genotypes and morphotypes of Alternaria contributing to apple blotch disease in Himachal Pradesh. These findings highlight the complexity of the pathogenic environment and hold significant implications for disease management in apple orchards.

Genetic Characterization of Three Soil Streptomyces Isolates Exhibiting Antiviral Activity Against TMV; Insights from 16S rRNA Gene Sequencing and RAPD Analysis

Genetic Characterization of Three Soil Streptomyces Isolates Exhibiting Antiviral Activity Against TMV; Insights from 16S rRNA Gene Sequencing and RAPD Analysis

Morphological, anatomical and genetic diversity of Nanhaia speciosa (Champ. ex Benth.) J.Compton & Schrire from Northern Vietnam

Abstract. Ong PX, Cao CB, Khang DT, Huy TG, Cao PB, Chu HD, Nguyen DV, La HV. 2024. Morphological, anatomical and genetic diversity of Nanhaia speciosa (Champ. ex Benth.) J.Compton & Schrire from Northern Vietnam. Biodiversitas 25: 1174-1184. Nanhaia speciosa (Champ. ex Benth.) J.Compton & Schrire has been considered a captivating plant species known for its remarkable attributes and contributions to ecological systems and human use. This medicinal plant originated from tropical Southeast Asia regions. However, the investigation of this species in Vietnam has been still lacking. This study comprehensively analyzed N. speciosa samples obtained in Vietnam; the morphological and anatomical characteristics of N. speciosa leaflets and flower samples collected from different regions were analyzed. As a result, the structural components of the flower were slightly similar between these samples, whereas the leaflet shape exhibited variations in the leaflet base, petiole, and leaflet apex. According to the ISSR and RAPD analysis, we demonstrated that N. speciosa found in ND genotypes (Tan Yen, Bac Giang) exhibited clearly different genetic backgrounds from CSS (Loc Binh, Lang Son) and CSD (Son Dong, Bac Giang) genotypes. Based on the clustering diagram of ISSR markers, 15 plant genotypes were classified into 2 large clusters, A and B, with genetic similarity ranging from 0.62 to 0.90. The RAPD dendrogram illustrated two main clusters, C and D, with genetic similarity ranging from 0.57 to 0.92. Therefore, this study could provide a solid foundation for identifying and characterizing N. speciosa species in Vietnam and a direction for advanced research on conservation, sustainable breeding, and exploiting pharmaceutical values.

Phylogenetic analysis among five medicinally significant Phyllanthus L. Species in Bangladesh based on taxonomic and molecular approach

A combination of taxonomical and molecular technique had done for authentic characterization of medicinally important five Phyllanthus species viz. P. acidus, P. emblica (small and large fruit form), P. niruri, P. reticulatus and P. urinaria. They were analyzed with several taxonomical parameters such as branching pattern, morphology of bark, leaves, flowers, fruits and seeds. A dichotomous bracketed key is created for easy identification of the species. RAPD analysis of five Phyllanthus species displayed that P. emblica and P. reticulatus were closely related whereas P. acidus and P. emblica were genetically distantly related. The genus Phyllanthus are diverse, as seen by the 71.68% polymorphism among the five studied species determined by RAPD analysis. The two forms (small and large fruit forms) of P. emblica showed similarity as well as dissimilarity in taxonomic and molecular features. Thus, a subtle revision is necessary in the taxonomical point of view to update their taxa. Dhaka Univ. J. Biol. Sci. 33(1): 121-131, 2024 (January)

Genetic discrimination of button mushroom Agaricus bisporus by DNA fingerprinting using RAPD marker

The investigation was conducted for DNA fingerprinting and genetic diversity analysis of five button mushroom strains (Agaricus bisporus-6, Agaricus bisporus-2, Agaricus bisporus-3, Agaricus bisporus-8 and Agaricus bisporus-5) using eight decamer RAPD primers (OPA01, OPA02, OPA03, OPA04, OPA07, OPB17, OPB12 and OPA10). A modified CTAB technique was used to isolate DNA. RAPD analysis resolved 152 scorable bands, 89 bands were monomorphic and 63 bands were polymorphic. The primer OPB17 amplified the highest number of band (30) and OPA01 amplified the lowest number of bands (09). The primer OPA04 produced the 8 polymorphic bands. Thus, it showed higher level of polymorphism (80%). Dendrogram based on linkage distance using Unweighted Pair Group Method of Arithmetic Means (UPGMA) indicated segregated of five button mushroom strains into two main clusters. Only Agaricus bisporus-6 (V1) grouped in cluster 1 (C1) while the major cluster C2 included all other strains, as well as V2 (Agaricus bisporus-2), V3 (Agaricus bisporus-3), V4 (Agaricus bisporus-8) and V5 (Agaricus bisporus-5). At the linkage distance of 50.5, the major cluster C2 formed sub-cluster C2A (Agaricus bisporus-3) and C2B (Agaricus bisporus-2, A. bisporus-8 & A. bisporus-5). Overall results from the dendrogram indicated that the V1 (Agaricus bisporus-6) button mushroom was shown to be outliers in the dendrogram, that is different from other strains because of its unique genetic makeup and high yields of this starin. The present work revealed that the DNA fingerprinting of five button mushroom strains based on RAPD showed significant different among the strains.

Anatomical and Molecular Study of Capsicum L. Taxa (Solanaceae Family) Cultivated in Iraq

Background: The anatomy of the stem and leaves are important to separate and identify species. The present work includes comparative anatomical and molecular studies of six taxa belonging to the genus Capsicum L. which are grown widely in Iraq. Anatomical and phylogenetic traits were observed for the identification of different taxa.Methods: For the anatomical study, stem, leaves and petioles of leaves were microscopically investigated, while for phylogenetics traits DNA was extracted from fresh and young leaves from each sample using RAPD and ISSR indices.Results: The anatomical results indicate that all taxa have anomocytic type of stomata. The glandular trichomes were found in the taxa C. frutescens and the taxa C. annum var. kkwari-gochu and C. annum was free from it, and these characteristics were important in the classification of the taxa of this genus. Phylogenetic results showed that 10 decamers of primers from 20 observed primers had diversity in cultivars of the genus Capsicum L. The genetic set of 10 RAPD primers and 8 Inter Simple Sequence Repeats (ISSR), and the pooled RAPD and ISSR data analyses support a genetic similarity range of 0.54, and 0.5 sequentially, and the taxa C. frutescens formed a single cluster in both molecular analyses in the genetic tree. The phylogenetic tree results also showed that other Capsicum cultivars are divided into two subgroups, one of which refers to the same variety C. annuum var. annuumm, and it was among the most important taxa studied, as it showed that it has two stages of maturity, physiological and vegetative maturity, so it appears morphologically different, but genetically integrated with the same taxa (Capsicum). Conclusions: The anatomical and molecular study of Capsicum taxa cultivated in Iraq provides valuable insights into the diversity and relationships between different species of this taxa.

Limited genetic variability and spatial population structure in grasshoppers between natural and metal-contaminated areas in Egypt.

Pollutants in an environment can have long-term implications for the species living there, resulting in local adaptations with implications for their genetic structure. Heavy metal pollutants infiltrate soils and groundwater, bioaccumulate in food webs, and negatively impact biota. In this study, we investigated the degree to which the genetic structure and variability of the slender green-winged grasshopper (Aiolopus thalassinus (Fabricius) (Orthoptera: Acrididae)) were impacted by heavy metal pollution and distance. We used the random amplified polymorphic DNA-polymerase chain reaction (RAPD-PCR) method to examine the genetic variability of populations in 3 heavy metal-polluted and 3 unpolluted locations across varying geographical distances in Egypt. The heavy metal concentrations of cadmium, copper, lead, and zinc were measured from the grasshopper tissue and soils. Sixty-nine unique and polymorphic bands were produced by 4 primers. Cluster and principal component analyses separated the populations inside and outside Cairo into 2 main branches, which were further divided into smaller branches corresponding to their geographical regions. We found no differences in the Shannon genetic diversity index between populations or with increasing heavy metal concentrations in either the soil or the grasshopper tissue. Our results showed a greater genetic variation among populations than between populations within the same location, indicating populations within locations were less differentiated than those between locations. The moderate correlation between genetic similarity and spatial distance suggests geographical isolation influenced grasshopper population differentiation. Based on the RAPD analysis, environmental pollutants and geographical distances impact the A. thalassinus population structure, potentially restricting gene flow between sites even at small spatial scales.

RAPD and SRAP analysis on species of Rosaceae family reveal taxonomic status of Pentactina rupicola endemic to the Democratic People’s Republic of Korea

RAPD and SRAP analysis on species of Rosaceae family reveal taxonomic status of Pentactina rupicola endemic to the Democratic People’s Republic of Korea

Phytoremediation and genetic adaptation potential of Jatropha curcas on heavy metals enriched mine tailings

BackgroundPhytoremediation is aninexpensive green method that uses metal-tolerant plants to extract these contaminants and restore the soil. MethodsThe phytoremediation potential and genomic DNA/genetic adaptability nature of Jatropha curcas was investigated by 90 days of greenhouse experiment.The genomic DNA stability was determined through RAPD analysis. Soil characterization results the magnesite mine tailing physicochemical parameters (pH, Total carbon, Total hardness, NPK, Cr, Pb, Mn, and Cd) were beyond the acceptable limits. Thus, the mine soil diluted with fertile soil (group a-f) to create different treatment groups. Significant FindingsThe results stated that soil diluted with maximum quantity of fertile soil showed maximum growth and considerably extracted the metals from the soil compared to undiluted (group e) soil and other groups. The BAF and TF values strongly suggests that the J.curcas is suitable candidature with phytoextraction potential. The RAPD analysis on whole genomic DNA revealed that the plan possesses considerable metal adaptation potential under metal stress condition confirmed by GTS and DNA polymorphism analyses through RAPD and also TSP analyses. Hence, this J. curcas can be employed as considerable plant with phytoextraction (as hyperaccumulator) potential to remove the heavy metals from the soil.

Resistance of Lactobacillus Sp. SKG 34 in The Digestive Tract of Rats Detected Using Random Amplified Polymorphic DNA Technique

In recent years, interest in probiotics, particularly Lactobacillus strains like Lactobacillus sp. SKG34, isolated from Sumbawa mare milk, has surged due to their potential health benefits. This strain holds promise as a probiotic agent, but understanding its behavior in the gastrointestinal (GI) tract is essential for effective application. This study aimed to investigate the resistance and persistence of Lactobacillus sp. SKG34 in the GI tract of rats. Rats were orally administered the strain at a concentration of 10^8 cells for 30 days. The probiotic’s ability to modulate gut microbiota and improve host health is a key area of interest. By utilizing techniques like PCR-RAPD, this research sought to elucidate the fate of Lactobacillus sp. SKG34 in the complex environment of the rat GI tract. Results revealed a significant increase in LAB population in cecal contents, from 3.06 x 10^9 cfu/g in the control group to 1.25 x 10^10 cfu/g in the probiotic group. RAPD analysis also detected Lactobacillus sp. SKG34 in approximately 23% of the total population of lactic acid bacteria in cecal contents, indicating its resistance and proliferation within the GI tract. Further investigation is warranted to fully understand the potential of Lactobacillus sp. SKG34 as a beneficial probiotic strain for human application.

Molecular, morphological, and biomolecular characterization of ethyl methanesulfonate-induced mutations in Aerides odoratum, an orchid

Aerides odoratum L. is a medicinal and ornamental orchid of the Eastern Himalayas, India. Its uses in pharmacology are nought because of its rare occurrence, longer life cycle, and lack of artificial methods for large-scale propagation. Protocorms (60 days old) were treated with various concentrations of ethyl methanesulfonate ranging from 0.025% to 0.5% for different durations (2, 5, 7, and 10 days) during M0 (treatment) in vitro generation. The survival of these protocorms and the generation of shoots and roots were noted. 10–20 plantlets of each treatment showing variation in the number and weight of shoots in M0 generation (treatment generation) were maintained for three subsequent generations. M3 (third generation) axenic plantlets were hardened in the orchidarium with a 75% survival frequency. Four mutant lines (M3V1–M3V4) were established based on RAPD analysis of the leaf DNA of 300-day-old plants. M3V-1 was noted as the best among all mutant lines based on morphological analysis, whereas M3V-2 was noted as the most superior in terms of having the highest quantity of osmolytes, pigments, stomata, and phenol. M3V-3 had maximum root length, leaf breadth, and carotenoids. M3V-4 showed the viridis chlorophyll spectrum as the most distinguishing factor. Hence, this standardized protocol can be used for the genetic improvement of A. odoratum.

Characterization of three citrullus lanatus (thunb.) Matsum. & nakai varieties by fluorescent chromosome staining and rapd analysis

Three commercial Citrullus lanatus varieties, namely Sonya, Kanya and Sweet black-2, were investigated with cyto-molecular techniques for characterization. Despite having similar somatic chromosome numbers and karyotype formulae (2n = 22), these three varieties had considerable diversities in Chromomycin A3 (CMA)- and 4′, 6-diamidino-2-phenylindole (DAPI)-banding patterns. The total somatic chromosomal length was longest in Sweet black-2 (71.44 ± 2.94 µm) and shortest in Sonya (42.31 ± 2.45 µm). Each variety's unique GC- and AT-rich chromatin composition was represented by a variety of numbers, percentages, and patterns of distribution. Eleven random primers were employed to evaluate the genetic diversity among three varieties. Each variety showed a distinct fingerprinting pattern with 88.72% polymorphism while having 10 of the same RAPD bands. Bangladesh J. Bot. 52(4): 1033-1040, 2023 (December)

Metal accumulation and genetic adaptation of Oryza sativa to Cadmiun and Chromium heavy metal stress: A hydroponic and RAPD analyses

This research was performed to assess the influence of Cd and Cr metals on growth, pigments, antioxidant, and genomic stability of Oryza sativa indica and Oryza sativa japonica were investigated under hydroponic conditions. The results revealed that significant metal influence on test crop growth, pigment content, metal stress balancing antioxidant activity in a dose dependent manner. Since, while at elevated (500 ppm) concentration of Cd as well as Cr metals the pigment (total chlorophyll, chlorophyll a, b and carotenoids) level was reduced than control; however antioxidant activity (total antioxidant, H2O2, and NO) was considerably improved as protective mechanisms to combat the metal toxicity and support the plant growth. Furthermore, the test crops under typical hydroponic medium (loaded with Cd and Cr as 200, 300, 400, and 500 ppm) growth conditions, effectively absorb the metals from medium and accumulated in the root and least quantity was translocated to the shoot of this test crops. Furthermore, typical RAPD analysis with 10 universal primers demonstrated that the genomic DNA of the test crops was adaptable to develop metal resistance and ensure crop growth under increased concentrations (500 ppm) of tested heavy metals. These findings suggest that these edible crops have the ability to accumulate Cd along with Cr metals, and additionally that their genetic systems have the ability to adapt to metal-stressed environments.