Maximum Genetic Diversity Research Articles

Genetic diversity analysis in Bt introgressed and non-Bt lines of upland cotton (Gossypium hirsutum L.)

Diversity analysis of Bt lines, a prerequisite to heterosis breeding, are rarely published. Diversity analysis of 140 cotton genotypes comprising of BGI, BGII and Non-Bt lines resulted in the grouping of genotypes into 20 clusters among which five had multiple genotypes and 15 others were solitary. Specific clustering of genotypes of BGI and BGII was not observed which got distributed across the clusters. The maximum and minimum inter-cluster distances were observed between two solitary clusters XVI and XVIII (159.8) as well as clusters VII and XI (6.4), respectively, reflecting diverse and close relationship among the Bt genotypes of those clusters. Two pairs of isogenic lines were located in the same clusters as they shared the same genetic background. The genetic background played important role in the diversity rather than the Bt status of genotype. Also, the maximum genetic diversity (64%) was arising from traits which were not related to Bt genes such as plant height, boll weight, and ginning out-turn when compared to the characters related to Bt gnes such as seed cotton yield and boll number (33%). In general, for seed cotton yield, BGI outperformed BGII lines. The study helped in developing high yielding hybrids through diverse parental line selections. Key words: Bt cotton, Genetic diversity, Introgression, D2 analysis

Resetting the paradigm of reproductive science and conservation

In the application of reproductive science to conservation breeding, it has long been assumed that artificial insemination using frozen thawed sperm would be the default technology. This has always been problematic considering the wide range of tolerance to freeze thawing among vertebrate sperm. Furthermore, those providing leadership for genome banking should be proactive to preserve maximum genetic diversity, however, for many species there is little or no sperm motility after thawing of cryopreserved sperm. In this review article, there is the contention that a much wider range of tissues should be banked, and the range of evolving advanced reproductive and developmental technologies should be considered for conservation breeding programs, to realize the maximum opportunities of genome banking to contribute to conservation of animal species.

Genetic Diversity of Tamarixia radiata Populations and Their Associated Endosymbiont Wolbachia Species from China

Tamarixia radiata is one of the established biocontrol pests against the major Asian citrus psyllid, Diaphorina citri, a vector of Candidatus Liberibacter that is a causal agent of citrus Huanglongbing (HLB) disease. Updated information and regional exploration on biocontrol pests are important elements for effective disease management strategies. In this study, the diversity and parasitism rate of T. radiata populations were evaluated. Due to the importance of the host–parasitoid relationship, the presence of Wolbachia as an endosymbiont was also investigated. The parasitism rate of various T. radiata populations from Ecuador and China ranged between 57.27% and 66.32%, respectively, with a non-significant emergence rate and a statistically similar sex ratio. Sequence analysis of ITS and COI from T. radiata populations was consistent with the morphological hypothesis that the collections represent a single species, whereas phylogeny of the wsp gene confirmed the presence of Wolbachia pipientis as an endosymbiont within T. radiata populations. Based on partial COI sequences, the maximum genetic diversity such as total haplotype diversity (Hd = 0.788), nucleotide, diversity (π = 0.2439), and average nucleotide difference (k = 171.844) was also estimated for different T. radiata populations. Furthermore, neutrality tests based on COI sequences indicated an overall contraction in T. radiata populations, whereas an expansion trend was observed in associated W. pipientis strains. This study clearly demonstrated the presence of genetically diverse T. radiata populations that were able to parasitize D. citri effectively, and these can be further explored as promising biocontrol candidates in integrated pest management strategies to solve citriculture economic loss caused by D. citri.

Development of genic-SSR markers and their application in revealing genetic diversity and population structure in an Eastern and North-Eastern Indian collection of Jack (Artocarpus heterophyllus Lam.)

Jack (Artocarpus heterophyllus) is a multi-purpose out-breeding tree species of the family Moraceae. We generated 42,928,887 high-quality expressed sequence reads, assembled them into 89,356 unigenes, and discovered 16,853 unigene-based perfect SSRs in A. heterophyllus. Thirty-eight polymorphic SSRs were used to analyze the genetic diversity and population structure of 224 germplasm accessions of A. heterophyllus constituting three populations from three agro-climatic zones, namely Eastern Plateau and Hills, Middle Gangetic Plain Region, and Eastern Himalayan Region, encompassing five Eastern and North-Eastern states of India. At the 38 SSR loci, we detected 142 alleles with a mean of 3.74 alleles per locus. The PIC values for the loci ranged from 0.25 to 0.69. The maximum genetic diversity was recorded in Eastern Plateau and Hills (I = 0.98, He = 0.52). The ANOVA analysis indicated significantly higher within-population variation (90%) than between populations (10%). The indirect estimation of gene flow (Nm) from PhiPT indicated significant gene flow among all three populations. The population structure analysis showed at least four distinct groups among the three populations with different introgression degrees. The NJ-based clustering grouped the 224 germplasm accessions into three main clusters, each with three sub-clusters. However, we did not observe distinct geographical structure among populations except some clustering among the germplasm accessions of the populations of geographically close locations. The transcriptome dataset and the SSR markers developed in the study would boost the species' molecular characterization, conservation, and specific need-based improvement.

Assessment of genetic diversity and population structure of oil palm (Elaeis guineensis Jacq.) field genebank: A step towards molecular-assisted germplasm conservation.

Oil palm (Elaeis guineensis) germplasm is exclusively maintained as ex situ living collections in the field for genetic conservation and evaluation. However, this is not for long term and the maintenance of field genebanks is expensive and challenging. Large area of land is required and the germplasms are exposed to extreme weather conditions and casualty from pests and diseases. By using 107 SSR markers, this study aimed to examine the genetic diversity and relatedness of 186 palms from a Nigerian-based oil palm germplasm and to identify core collection for conservation. On average, 8.67 alleles per SSR locus were scored with average effective number of alleles per population ranging from 1.96 to 3.34 and private alleles were detected in all populations. Mean expected heterozygosity was 0.576 ranging from 0.437 to 0.661 and the Wright’s fixation index calculated was -0.110. Overall moderate genetic differentiation among populations was detected (mean pairwise population FST = 0.120, gene flow Nm = 1.117 and Nei’s genetic distance = 0.466) and this was further confirmed by AMOVA analysis. UPGMA dendogram and Bayesian structure analysis concomitantly clustered the 12 populations into eight genetic groups. The best core collection assembled by Core Hunter ver. 3.2.1 consisted of 58 palms accounting for 31.2% of the original population, which was a smaller core set than using PowerCore 1.0. This core set attained perfect allelic coverage with good representation, high genetic distance between entries, and maintained genetic diversity and structure of the germplasm. This study reported the first molecular characterization and validation of core collections for oil palm field genebank. The established core collection via molecular approach, which captures maximum genetic diversity with minimum redundancy, would allow effective use of genetic resources for introgression and for sustainable oil palm germplasm conservation. The way forward to efficiently conserve the field genebanks into next generation without losing their diversity was further discussed.

English

The molecular diversity of Tomato spotted wilt virus (TSWV) isolates from Pakistan was investigated based on nucleocapsid protein (N) gene. It revealed that the Pakistani isolates shared 98.2–99.3% (nt) and 95.7–97.4% (aa) identities with each other and 97.2–99.3% (nt) and 92.7–97.8% (aa) with other TSWV isolates retrieved from Genbank. In a neighbour-joining phylogenetic reconstruction, four Pakistani isolates clustered with South Korean and Turkish isolates and one with Australian and South African isolates. All the Pakistani isolates shared maximum genetic diversity (0.024–0.039 and 0.026–0.029) with South African (AJ296600) and Australian (AY879109) isolates and the lowest values of genetic diversity (0.009–0.013) was recorded with Czech Republican isolate (AJ296599). The gene differentiation co-efficient value (Fst) was 0.33 less than standard value noticed as 0.05145, between globally reported and Pakistani TSWV isolates considering it a frequent gene flow. The significant values of statistical tests based on three genetic differentiation analysis; Ks⃰; 4.86231, Z; 34.27778 and Snn; 0.55556 were observed. The negative values were recorded according to statistical test as Fu, & Li’s D ⃰ (-2.55465), Fu, & Li’s F ⃰ (-2.78103) and one positive value from Tajima’s D (2.10697). These results indicate low polymorphism frequency in TSWV population of Pakistan. © 2021 Friends Science Publishers

Genetic conservation strategies of endemic plants from edaphic habitat islands: The case of Jacobaea auricula (Asteraceae)

Conservation genetics is a well‐established and essential scientific field in the toolkit of conservation planning, management, and decision‐making. Within its framework, phylogeography allows the definition of conservation strategies, especially in threatened endemic plants. Gypsum and salt-rich outcrops constitute a model example of an edaphic island-like habitat and contain rare and endemic species, many of them threatened. This is the case of Jacobaea auricula, an Iberian gypsohalophytic species with biological, ecological, and conservation interest. Genetic-based criteria were used to preserve the highest possible percentage of the species' genetic pool as well as to dispose of a set of genotypes for translocation and/or reinforcement planning of degraded populations. Relevant Genetics Units for Conservation (RGUCs) were selected as in situ conservation planning. As a complementary ex situ measure, the optimal contribution for the populations to maximize the genetic pool within each genetic cluster was calculated. To preserve the maximum genetic diversity and the highest percentage of rare AFLP bands possible, eight RGUCs were selected; the ex situ conservation design included twenty-one populations, gathering all haplotypes and ribotypes. Our genetic conservation proposal of J. auricula would improve the implementation of future genetic conservation measures, as a species model of endemic plants from edaphic habitat islands.

All Populations Matter: Conservation Genomics of Australia’s Iconic Purple Wattle, Acacia purpureopetala

Maximising genetic diversity in conservation efforts can help to increase the chances of survival of a species amidst the turbulence of the anthropogenic age. Here, we define the distribution and extent of genomic diversity across the range of the iconic but threatened Acacia purpureopetala, a beautiful sprawling shrub with mauve flowers, restricted to a few disjunct populations in far north Queensland, Australia. Seed production is poor and germination sporadic, but the species occurs in abundance at some field sites. While several thousands of SNP markers were recovered, comparable to other Acacia species, very low levels of heterozygosity and allelic variation suggested inbreeding. Limited dispersal most likely contributed towards the high levels of divergence amongst field sites and, using a generalised dissimilarity modelling framework amongst environmental, spatial and floristic data, spatial distance was found to be the strongest factor explaining the current distribution of genetic diversity. We illustrate how population genomic data can be utilised to design a collecting strategy for a germplasm conservation collection that optimises genetic diversity. For this species, inclusion of all field sites will capture maximum genetic diversity for both in situ and ex situ conservation. Assisted cross pollination, within and between field sites and genetically structured groups, is recommended to enhance heterozygosity particularly at the most disjunct sites and further fragmentation should be discouraged to avoid loss of genetic connectivity.

The Conception of Microbial Preparations Development for a Crop Production

As a result of the analysis of scientific literature data and based on our experimental data, we present the conception of mutual relations between beneficial microorganisms and plants in the soil: a) for the purposeful management of processes in agro- and natural phytocenoses it is necessary to consider all components of the plant-microbial community (plant, arbuscular mycorrhizas, nodule bacteria and all microorganisms stimulating plants growth and development, both endophytic and epiphytic), as a uniform gen-metabolic net; b) it is necessary to consider, that the rate of microsymbionts genomes evolution exceeds the rate of plant evolution and consequently the plant should be considered as the most genetically stable in time, key component controlling the efficiency of plant-microbial systems functioning. According to the basic conception of intensive agriculture within several decades all over the world, the selection of new breeds of agricultural plants was conducted on a high agrotechnical level with the application of high doses of fertilizers and chemicals. The attention was paid only to the negative influence of a pathogenic microbiota on plants and according to this, the resistance of plants to such conditions. As a rare example, in the case of legumes farmers took into account the symbiotic nitrogen fixation that is mutualistic interactions of plants with nodule bacteria. It is necessary to notice, that the genetic systems of legumes controlled the interaction with nodule bacteria, arbuscular mycorrhiza and plant growth promoting bacteria (PGPB), have a series of common genes. It should be considered as a uniform polygene net and to be the object of selection on integral feature “efficiency of interaction with microorganisms beneficial to plants”, instead on separate signs characterizing the efficiency of formation of separate types of mutually advantageous plant-microbial symbioses; c) at the beginning of plant selection history, not having the effective technologies and knowledge about the structure of plant genetic system, monitoring mutual relations of plants with microorganisms, scientists breeders intuitively followed the laws dictated by natureconducted selection against an undisturbed structure of plant beneficial microorganisms community on the integral feature of plant productivity. Today it is necessary to return to the initial practice of selection, but with the account of effective technologies and new knowledge of plant-microbial interactions and to make plant selection to increase the symbiotic potential of such interaction against its maximum genetic diversity. It is reasonable to conduct plant selection on such features as additional biomass, saved up by the formation of the mutualistic plant-microbial system and quality of received production. Due to such selection, the commercial breeds of agricultural plants maximum efficiently operating the interaction with microorganisms in agrophytocenosis will be received. As a result of applying this conception, the technologies for production of complex microbial preparations BIST, Pseudorizobin and Zamin were developed, patented and successfully tested in the Republic of Uzbekistan.

Adaptive Gene Content and Allele Distribution Variations in the Wild and Domesticated Populations of Saccharomyces cerevisiae.

Recent studies on population genomics of Saccharomyces cerevisiae have substantially improved our understanding of the genetic diversity and domestication history of the yeast. However, the origin of the domesticated population of S. cerevisiae and the genomic changes responsible for ecological adaption of different populations and lineages remain to be fully revealed. Here we sequenced 64 African strains from various indigenous fermented foods and forests in different African countries and performed a population genomic analysis on them combined with a set of previously sequenced worldwide S. cerevisiae strains representing the maximum genetic diversity of the species documented so far. The result supports the previous observations that the wild and domesticated populations of S. cerevisiae are clearly separated and that the domesticated population diverges into two distinct groups associated with solid- and liquid-state fermentations from a single ancestor. African strains are mostly located in basal lineages of the two domesticated groups, implying a long domestication history of yeast in Africa. We identified genes that mainly or exclusively occur in specific groups or lineages and genes that exhibit evident group or lineage specific allele distribution patterns. Notably, we show that the homing endonuclease VDE is generally absent in the wild but commonly present in the domesticated lineages of S. cerevisiae. The genes with group specific allele distribution patterns are mostly enriched in functionally similar or related fundamental metabolism processes, including the evolutionary conserved TOR signaling pathway.

Genetic diversity and population structure analysis of Emmenopterys henryi Oliv., an endangered relic species endemic to China

A simple sequence repeat (SSR) marker was used to assess the genetic diversity and population structure of an endangered relic species Emmenopterys henryi Oliv., endemic to China. A total of 124 samples from six populations were analyzed using eight pairs of SSR primers. Total 114 alleles were detected with an average of 14.3 alleles per locus. The presence of null alleles can result in low genetic diversity parameters (He and allelic richness) for all loci and mostly likely caused the deviation from Hardy–Weinberg equilibrium (HWE). The Polymorphism information content (PIC) values were higher which indicates that selection of SSR markers were suitable choice for assessing the genetic diversity in E. henryi. Our results revealed that the natural populations of E. henryi have a high degree of genetic diversity. Genetic diversity amongst the six E. henryi populations in decreasing order were: GJY > LS > DWS > WYS > HS > JGS. Further, genetic structure and the Neighbor-Joining (NJ) cluster analysis indicated that there were cross-mixing among the 124 samples. Four populations (i.e., HS, DWS, JGS and WYS) were clustered in one group, whereas LS and GJY population were clustered separately as two groups. A Principal Component Analysis (PCA) also showed a similar clustering trend. The results of Fst (0.085) and AMOVA indicated that the genetic variation resided within the populations and existence of frequent gene exchanges among populations. Based on these results, populations with abundant genetic variation and rare alleles should be conserved in situ and ex situ. Furthermore, seeds from the different populations with high levels of genetic diversity could be collected and propagated in order to capture the maximum available genetic diversity. The present study on genetic diversity of E.henryi could be helpful in expanding the understanding on species survival and also for developing an effective long term conservation strategy.

Molecular diversity of babycorn (Zea mays) inbred lines by rice SSR Marker

A set of 24 maize inbred lines were analysed by using Rice SSR markers (40). Out of which, 14 SSR markers were found to be amplified and reproducible in which 10 markers showed polymorphism and rest showed monomorphic bands. A total of 32 polymorphic alleles were found. The average polymorphic information content (PIC) value was 0.28 with maximum 0.36 (RM552) and minimum 0.14 (RM216). By the use of Unweighted paired group method (UPGMA) for cluster analysis and formed four clusters in which genotype CML425 was found extremely diverse from rest of the genotypes. This represents its unique genetic structure from the rest genotypes. The overall result indicates that the genotypes present in these clusters have maximum genetic diversity that will help in classifying various genotypes in exact heterotic groups for future breeding programme. The study provided sufficient information about the genetic diversity of maize inbreds and that also identified common markers for rice and maize genetic studies that can be helpful for reducing cost effective measures for producing crop specific markers. In this way, identified clusters may be used for future breeding programme. This study also concluded that SSR marker can be taken as good complementing tool.

Unravelling the genetic diversity and phylogenetic relationships of Indian Capsicum through fluorescent banding

Hot chilli species of Capsicum are one of the most significant spice crops in India having several genetically distinct cultivars. The present study was targeted to upgrade chromosomal database of 15 cultivars belonging to C. annuum L., C. frutescens L. and C. chinense Jacq. EMA-based fluorochrome banding with GC-specific stain Chromomycin A3 (CMA) was elemental to reveal specialization in karyotypes that could not be traced out by Giemsa-stained preparations. CMA banding pattern was combined with karyomorphometric indices to statistically evaluate chromosomal relationship among the cultivars. The marker chromosome pairs 11 and 12 containing nucleolar CMA bands could be suggested as the evolutionary landmarks in ‘C. annuum complex’. We found direct correspondence between fruit morphotype variation and CMA banding pattern to demonstrate maximum genetic diversity within C. annuum, followed by C. frutescens while Bhut jolokia of C. chinense displayed genetic uniformity. UPGMA phenogram upheld distinct species separation, cultivar diversity and relationships within and among the species. Out of nine C. annuum cultivars, at least two cultivars showed some sort of genetic relationship with C. chinense, particularly the Ghee cultivar shares more proximity with C. chinense. The fluorescent karyotype database reliably symbolized uniqueness of Capsicum germplasm of India, especially from the NEH sector that grows Bhut jolokia. Our attempt is believed to complement genomic investigation in the popular and exotic chilli cultivars of India and interest breeders in search of alternative genetic resources.

Comparison Between Core Set Selection Methods Using Different Illumina Marker Platforms: A Case Study of Assessment of Diversity in Wheat.

Collections of plant genetic resources stored in genebanks are an important source of genetic diversity for improvement in plant breeding programs and for conservation of natural variation. The establishment of reduced representative collections from a large set of genotypes is a valuable tool that provides cost-effective access to the diversity present in the whole set. Software like Core Hunter 3 is available to generate high quality core sets. In addition, general clustering approaches, e.g., k-medoids, are available to subdivide a large data set into small groups with maximum genetic diversity between groups.Illumina genotyping platforms are a very efficient tool for the assessment of genetic diversity of plant genetic resources. The accumulation of genotyping data over time using commercial genotyping platforms raises the question of how such huge amount of information can be efficiently used for creating core collections. In the present study, after developing a 15K wheat Infinium array with 12,908 SNPs and genotyping a set of 479 hexaploid winter wheat lines (Triticum aestivum), a larger data set was created by merging 411 lines previously genotyped with the 90K iSelect array. Overlaying the markers from the 15K and 90K arrays enabled the identification of a common set of 12,806 markers, suggesting that the 15K array is a valuable and cost-effective resource for plant breeding programs.Finally, we selected genetically diverse core sets out of these 890 wheat genotypes derived from five collections based on the common markers from the 15K and 90K SNP arrays. Two different approaches, k-medoids and Core Hunter 3 were compared,and k-medoids was identified as an efficient method for selecting small core sets out of a large collection of genotypes while retaining the genetic diversity of the original population.

Genome skimming and microsatellite analysis reveal contrasting patterns of genetic diversity in a rare sandhill endemic (Erysimum teretifolium, Brassicaceae).

Barriers between islands often inhibit gene flow creating patterns of isolation by distance. In island species, the majority of genetic diversity should be distributed among isolated populations. However, a self-incompatible mating system leads to higher genetic variation within populations and very little between-population subdivision. We examine these two contrasting predictions in Erysimum teretifolium, a rare self-incompatible plant endemic to island-like sandhill habitats in Santa Cruz County, California. We used genome skimming and nuclear microsatellites to assess the distribution of genetic diversity within and among eight of the 13 remaining populations. Phylogenetic analyses of the chloroplast genomes revealed a deep separation of three of the eight populations. The nuclear ribosomal DNA cistron showed no genetic subdivision. Nuclear microsatellites suggest 83% of genetic variation resides within populations. Despite this, 18 of 28 between-population comparisons exhibited significant population structure (mean FST = 0.153). No isolation by distance existed among all populations, however when one outlier population was removed from the analysis due to uncertain provenance, significant isolation by distance emerged (r2 = 0.5611, p = 0.005). Population census size did not correlate with allelic richness as predicted on islands. Bayesian population assignment detected six genetic groupings with substantial admixture. Unique genetic clusters were concentrated at the periphery of the species' range. Since the overall distribution of nuclear genetic diversity reflects E. tereifolium's self-incompatible mating system, the vast majority of genetic variation could be sampled within any individual population. Yet, the chloroplast genome results suggest a deep split and some of the nuclear microsatellite analyses indicate some island-like patterns of genetic diversity. Restoration efforts intending to maximize genetic variation should include representatives from both lineages of the chloroplast genome and, for maximum nuclear genetic diversity, should include representatives of the smaller, peripheral populations.

Molecular identification of seven new Zygopteran genera from South China through partial cytochrome oxidase subunit I (COI) gene

The study was carried out in eight provinces of China, with 16 different localities. A total of 150 adult damselflies were collected for the study from the area. Mitochondrial (COI) was the target gene to sequence from all 51 representative samples of the entire collection. From the resulted sequences, ten species belonging to seven genera and four families were identified. The families are Calopterygidae, Coenagrinidae, Chlorocyphidae and Devadattiade. After alignment through BioEdit v6, MEGA7 was used for phylogenetic tree construction as well as the calculation of genetic divergence, whereas genetic diversity was calculated by DnaSP v5. All species from the respective families had clustered together within the groups, but divided into sub-groups. Maximum genetic divergence (9.31%) was found in the genus Rhinocypha, followed by Hetaerina with (8.23%), while, minimum divergence was observed for the genus Ceriagrion (0.32%) followed by Ischnura (0.48%). However, significant genetic diversity was found for all sequences at 346 mutations confirmed by two tests, Tajima's D and Fu's Fs. Maximum genetic diversity among genera was also observed, the genus Hetaerina has maximum genetic diversity (181 mutations) followed by Rhinocypha (68 mutations) while minimum genetic diversity was observed for the genus Ceriagrion followed by Ischnura. The presented results showed a higher diversity of damselflies in the south China regions.

Genetic structure of Iranian indigenous sheep breeds: insights for conservation.

Genetic structure and genetic diversity levels of indigenous Iranian sheep breeds are not clear, despite the interest this region has in itself as an important center for domestication of livestock. Early population genetic studies have reported high levels of diversity among Iranian sheep breeds until recently, when high admixture levels and genetic homogeneity have been detected. The rapid reduction of diversity observed in Iranian breeds might be due to an increasing trend of intensive crossbreeding practices or even total replacement of native breeds by highly specialized and productive ones. From a conservative perspective, this situation is highly concerning; thus, it might be wise to consider a conservation program in Iran to preserve the original genetic diversity in native sheep breeds. In this study, a total of 1065 animals with the purest morphological features representing 24 Iranian indigenous sheep breeds were sampled, corresponding to ancestral breed diversity. These samples were genotyped for 17 microsatellite loci in order to (1) determine the native ancestral diversity of Iranian breeds, (2) define the degree of genetic relationship among studied breeds, and (3) assess conservation priorities among defined groups. Our results showed no recent loss of diversity, but high genetic diversity levels for indigenous sheep breeds in Iran. Indeed, the analysis of conservation priorities pointed out the importance of 8 breeds for maintaining Iranian sheep breeds' maximum genetic diversity. Thus, under a genetic perspective, these 8 breeds should be the ones included into conservation programs for restocking endangered areas.

ANALYSIS OF FORESTS’ GENETIC VULNERABILITY AND ARGUMENTS TO REDUCE DEFORESTATION

Abstract Forests play an essential role in protecting natural resources such as soil, water and environmental services. The aims of the current study are to analyze definitions involving issues such as forest cover and its vulnerability, as well as to present arguments to help reducing deforestation. Solutions focused on mitigating tree vulnerability are herein presented, namely: genetic conservation and local creation of genetic databases on natural forests; pursuit of maximum genetic diversity to maintain reproduction index and avoid cloning effects; scientifically investigating how to help trees to adapt to environmental changes; use of genetic improvement and programs such as Payment for Environmental Services, Bolsa Floresta Program, Crop-Livestock-Forest Integration and ABC Program to reduce deforestation in tropical forests.

Genetic diversity and core subset selection inex situseed collections of the banana crop wild relativeMusa balbisiana

AbstractCrop wild relatives (CWRs) play a key role in crop breeding by providing beneficial trait characteristics for improvement of related crops. CWRs are more efficiently used in breeding if the plant material is genetically characterized, but the diversity in CWR genetic resources has often poorly been assessed. Seven seed collections ofMusa balbisiana, an important CWR of dessert and cooking bananas, originating from three natural populations, two feral populations and twoex situfield collections were retrieved and their genetic diversity was quantified using 18 microsatellite markers to select core subsets that conserve the maximum genetic diversity. The highest genetic diversity was observed in the seed collections from natural populations of Yunnan, a region that is part ofM. balbisiana's centre of origin. The seeds from theex situfield collections were less genetically diverse, but contained unique variation with regards to the diversity in all seed collections. Seeds from feral populations displayed low genetic diversity. Core subsets that maximized genetic distance incorporated almost no seeds from theex situfield collections. In contrast, core subsets that maximized allelic richness contained seeds from theex situfield collections. We recommend the conservation and additional collection of seeds from natural populations, preferentially originating from the species' region of origin, and from multiple individuals in one population. We also suggest that the number of seeds used forex situseed bank regeneration must be much higher for the seed collections from natural populations.

Evaluating Genetic Diversity Within Genus Jasminum L. (Oleaceae) Using Intersimple Sequence Repeats (ISSR) Marker

Jasmines are an important group of plants extensively used in the perfumery industry, preparation of garland and for ornamental purposes. To analyze the genetic potential of the group, the authors evaluated its genetic diversity. Intersimple sequence repeats (ISSR) markers were used to evaluate genetic diversity among 40 accessions of 23 Jasminum species including six endemic species. The present study is the first report of the efficacy of 10 shortlisted ISSR markers out of 30 primers screened. Among 23 Jasminum species, J. bignoniaceum revealed maximum genetic diversity and Shannon’s Index. Results revealed that the accessions of Jasminum species are grouped into three major clades, showing close agreement with the morphological relatedness. The diversity analysis also showed that the members of section Alternifolia are the ancestor to the rest of the Jasminum spp. The study provides direction for the future population study on Jasminum spp. This is the first report on the genetic diversity assessment of Indian Jasminum spp. incorporating approximately 50% species.