The Suwan population is a well-known maize germplasm that has greatly contributed to the development of maize breeding in tropical and subtropical regions, especially in southern China. Inbred lines ...derived from the Suwan population always contain stronger resistance and extensive adaptability in different environments. To evaluate the genetic character of inbred lines derived from the Suwan population, a panel including 226 inbred line derived from the Suwan population and temperate resources was assembled and genotyped by using MaizeSNP50 BeadChip, which contained 56,110 genome-wide single nucleotide polymorphism (SNP) markers. This panel contained 98 temperate inbred line and 128 lines derived from the Suwan population.
The results showed that high genetic diversity was found, with PIC and GD to be 0.67 and 0.60, respectively. In addition, two novel subgroups were identified, with representative inbred lines as HCL645 and Ki32, respectively. One acknowledged heterotic group of Iowa Stiff Stalk Synthetic (SS) was also identified in this study. This study can provide some additional scientific evidence for heterotic group division and use in maize. Additionally, lower linkage disequilibrium (LD) levels and weaker genetic relationships were found, with an average LD level of 41.15 kb that varied from 3.5 to 96 kb. A total of 82.8% of paired relative kinships ranged from 0.05 to 0.28.
These results would not only facilitate maize breeding practices in tropical and subtropical regions, but also revealed that this panel can be used in dissecting the genetic basis of complex quantitative traits' variations by using genome-wide association studies (GWAS).
The herbal medicinal genus
L., belonging to the Ranunculaceae family, represents the earliest diverging lineage within the eudicots. It currently comprises of two subgenera,
. subgenus
and
. subg.
. ...The complete chloroplast (cp) genome sequences were characterized in three species:
,
, and
in subg.
and compared to other
species to clarify their phylogenetic relationship and provide molecular information for utilization of
species particularly in Eastern Asia. The length of the chloroplast genome sequences were 156,109 bp in
, 155,625 bp in
and 157,215 bp in
, with each species possessing 126 genes with 84 protein coding genes (PCGs). While genomic rearrangements were absent, structural variation was detected in the LSC/IR/SSC boundaries. Five pseudogenes were identified, among which Ψ
19 and Ψ
1 were in the LSC/IR/SSC boundaries, Ψ
16 and Ψ
A in the LSC region, and Ψ
15 in the IRb region. The nucleotide variability (
) of
was estimated to be 0.00549, with comparably higher variations in the LSC and SSC than the IR regions. Eight intergenic regions were revealed to be highly variable and a total of 58-62 simple sequence repeats (SSRs) were detected in all three species. More than 80% of SSRs were present in the LSC region. Altogether, 64.41% and 46.81% of SSRs are mononucleotides in subg.
and subg.
, respectively, while a higher percentage of di-, tri-, tetra-, and penta- SSRs were present in subg.
. Most species of subg.
in Eastern Asia were first used for phylogenetic analyses. The availability of the complete cp genome sequences of these species in subg.
will benefit future phylogenetic analyses and aid in germplasm utilization in
species.
Trichoderma species are found in soil and in association with plants. They can act directly or indirectly in the biological control of plant diseases and in the promotion of plant growth, being among ...the most used fungi in the formulation of bioproducts applied to agricultural systems. The main objective of this study was to characterize at a first-tier level a collection of 67 Trichoderma isolates from various tropical sources, based solely on sequencing of the internal transcribed spacer (ITS) region of the rRNA genes. Our goal was to provide a preliminary idea of the baseline diversity in this collection, to combine this information later with an array of other isolate-specific physiological data. This study provides a required knowledge at molecular level for assessment of this germplasm potential as a source of biotechnological products for beneficial effects in plants.
Sequencing of the ITS region showed that the 67 Trichoderma isolates belonged in 11 species: T. asperellum, T. atroviride, T. brevicompactum, T. harzianum, T. koningiopsis, T. longibrachiatum, T. pleuroticola, T. reesei, T. spirale, T. stromaticum and T. virens. A total of 40.3% of the isolates were very closely related to each other and similar to T. harzianum. The baseline genetic diversity found indicates that the collection has different genotypes, which can be exploited further as a source of bioproducts, aiming at providing beneficial effects to plants of interest to cope with biotic and abiotic stresses.
Valeriana jatamansi Jones germplasm collected from sub-temperate Himalayan region of Uttarakhand and North-East state of Meghalaya, India was evaluated under identical conditions at National Bureau ...of Plant Genetic Resources, Bhowali, India, to study germplasm diversity based on essential oil composition. Twenty one compounds were identified in V. jatamansi root oil by GC and GC-MS. The major compounds identified were patchouli alcohol (0.4-63.7%), maaliol (2.9-53.8%), seychellene (4.1-27.4%), calarene/ί-gurjunene (3.0-20.8%), α-santalene (0.6-12.0%). Other compounds present were bornyl acetate (0.6-1.5%), α-guaiene (0.7-2.3%), α-bulnesene/d-guaiene (0.7-6.3%), 7-epi-α-selinene (0.4-1.4%), kessane (2.1-3.3%), spathulenol (0.7-3.4%), viridiflorol (0.9-7.1%), α-patchoulene (0.8-6.6%), ί-patchoulene (0.4-0.8%). Two superior chemotypes identified in V. jatamansi oil from Uttarakhand were: patchouli alcohol rich (IC573221, 63.7%) and maaliol rich (IC573222, 53.8%; IC589096, 51.7%), while accession from north-east was patchouli alcohol rich chemotype (IC574522, 57.2%). These superior chemotypes with higher amounts of patchouli alcohol and maaliol could be used for promoting cultivation as well as for meeting need of pharmaceutical industries.
Iron and zinc are essential micronutrients for normal human growth and development and are commonly deficient in diets of the most vulnerable. Common bean (Phaseolus vulgaris L.), one of the leading ...staple foods in East and Central Africa, is a valuable source of quality protein and micronutrients, specifically iron, zinc, and vitamins. Natural variation in micronutrient concentration exists among bean germplasm. Identification of varieties with high iron and zinc seed concentration (FESEED/ZNSEED) for promotion in food systems and utilisation in breeding programs is one strategy of addressing the problem of malnutrition in Africa. Three hundred and four lines sourced from the International Centre for Tropical Agriculture (CIAT) and its partners through the Pan Africa Bean Research Alliance (PABRA), were evaluated for agronomic traits, disease response, yield, FESEED, and ZNSEED. They were organized in four groups; PABRA fast track, Rwanda seeds of hope, HarvestPlus regional nutrition nursery and Uganda collection. Six checks were included; a universal high FESEED climbing bean (MIB465), low FESEED regional climbing bean (Decelaya), universal low FESEED bush bean (DOR500), regional high FESEED bush bean (RWR2154), and two yield checks (CAL96 and Vuninkingi for bush and climbing bean). The FESEED checks were selected based on their relative performance to other genotypes in several experiments by a community of bean breeders through the H+ program. Field trials were established at the National Agricultural Laboratories, Kawanda from 2011 to 2013. Days to maturity and flowering, vigor, yield, and reaction to diseases were evaluated. Micronutrient analysis was conducted using X-ray Fluorescence (XRF) and data confirmed using Inductively Coupled Plasma Atomic Emission Spectrometry (ICP-AES). Lines were significantly different (Pless than or equal to0.05) in all the parameters assessed. FESEED and ZNSEED varied highly between seasons and among the entries ranging between 36-90 ppm and 24-47 ppm across the four nurseries. Twenty-six lines were selected as high iron beans (HIBs) based on XRF data; 12 of these were confirmed as HIB based on ICP data that is more accurate. Of these, two bush beans, Jesca (large purple speckled) and RW547 (medium grey) and two climbing beans, CAB2 (medium white seeded) and Ndimirakaguja (small cream) were the most superior in FESEED across seasons. With the exception of CAB2, these lines were relatively high yielding >2000 kgha.sup.-1. There was no significant correlation of FESEED or ZNSEED to yield. Nonetheless, FESEED and ZNSEED positively (0.59) correlated indicating that selection for superiority in one variable would result in a high value in the other.
Understanding farmers' needs and local genetic resources are crucial steps to improve and conserve the potato crop. A study was conducted to understand what potato traits Ethiopian farmers consider ...most important, and to characterize the diversity and distribution of local varieties. Growers from six districts were surveyed in 2012 and 2014. Based on the survey results, participatory variety selection (PVS) activities were conducted in two districts during two production seasons. Simultaneously, local varieties were collected from northwest and southern Ethiopia and characterized using molecular and morphological markers. Farmers identified 23 traits they considered important for variety selection, with the degree of importance for each trait varying across gender groups, agro-ecological zones, and growing seasons, as well as with extent of market access. The distribution of local varieties varied by agro-ecological zone, cropping system and proximity to markets. Our genetic fingerprinting and morphological characterization further revealed that, 34% of 44 local potato varieties collected are truly unique, the rest were duplicates, known by different names. These unique Ethiopian local varieties harbour considerable genetic variation, compared to the variation found in European and North American clones. Although local varieties may have lower yield than commercial varieties, they have other desirable attributes that make them well suited for alternative uses and different agro-ecologies.
Background. Miguel Hernandez University (Spain) created a germplasm bank of the varieties of pomegranate from different Southeastern Spain localities in order to preserve the crop's wide genetic ...diversity. Once this collection was established, the next step was to characterize the phenotype of these varieties to determine the phenotypic variability that existed among all the different pomegranate genotypes, and to understand the degree of polymorphism of the morphometric characteristics among varieties. Methods. Fifty-three pomegranate (Punica granatum L.) accessions were studied in order to determine their degree of polymorphism and to detect similarities in their genotypes. Thirty-one morphometric characteristics were measured in fruits, arils, seeds, leaves and flowers, as well as juice characteristics including content, pH, titratable acidity, total soluble solids and maturity index. ANOVA, principal component analysis, and cluster analysis showed that there was a considerable phenotypic diversity (and presumably genetic). Results. The cluster analysis produced a dendrogram with four main clusters. The dissimilarity level ranged from 1 to 25, indicating that there were varieties that were either very similar or very different from each other, with varieties from the same geographical areas being more closely related. Within each varietal group, different degrees of similarity were found, although there were no accessions that were identical. These results highlight the crop's great genetic diversity, which can be explained not only by their different geographical origins, but also to the fact that these are native plants that have not come from genetic improvement programs. The geographic origin could be, in the cases where no exchanges of plant material took place, a key criterion for cultivar clustering. Conclusions. As a result of the present study, we can conclude that among all the parameters analyzed, those related to fruit and seed size as well as the juice's acidity and pH had the highest power of discrimination, and were, therefore, the most useful for genetic characterization of this pomegranate germplasm banks. This is opposed to leaf and flower characteristics, which had a low power of discrimination. This germplasm bank, more specifically, was characterized by its considerable phenotypic (and presumably genetic) diversity among pomegranate accessions, with a greater proximity existing among the varieties from the same geographical area, suggesting that over time, there had not been an exchange of plant material among the different cultivation areas. In summary, knowledge on the extent of the genetic diversity of the collection is essential for germplasm management. In this study, these data may help in developing strategies for pomegranate germplasm management and may allow for more efficient use of this germplasm in future breeding programs for this species.
Climate change poses significant risks to future crop productivity as temperatures rise, rainfall patterns become more variable, and pest and disease pressures increase. The use of crop genetic ...resources to develop varieties more tolerant to rapidly changing environmental conditions will be an important part of agricultural adaptation to climate change. Finding new genetic traits that can facilitate adaptationand incorporating them into commercially successful varietiesis time-consuming, expensive, and technically difficult. This book reviews the types of genetic resources, the ways they have been used, and how they might be used in the future. The book also discusses economic, scientific, and institutional factors that will determine the extent of genetic resource use and the benefits it might bring to climate change adaptation. Moreover, this title evaluates economic and institutional factors influencing the flow of genetic resources, including international agreements, and their significance for agricultural research and development in the United States. Finally, the book examines the composition of U.S. and international seed markets, regulations affecting agricultural seeds, the structure and evolution of the seed industry, and trends in private and public R&D in plant breeding.