National Germplasm Research Articles

Development of SSR markers related to agarwood production and genetic diversity of Aquilaria sinensis (Lour.) Spreng wild populations

Aquilaria sinensis (Lour.) Spreng is an economically important tree that produces agarwood when subjected to mechanical wounding. However, the information regarding its heredity is limited. The breeding of A. sinensis has been hindered due to ambiguity in the sources of germplasm, genetic background, and varietal information. Simple sequence repeat (SSR) markers are ideal for studying genetic diversity and germplasm identification in plants. They offer the advantages of high polymorphism, good reproducibility, and co–dominance. Here, we mined SSR markers within agarwood–inducing genes and used them to explore the genetic diversity among A. sinensis natural germplasm. A total of 407 SSR loci were identified within 92 genes. We designed 96 primer pairs, among which 16 showed polymorphism and were subsequently used to analyze the genetic diversity and population structure of 179 A. sinensis individuals. A total of 107 alleles were identified, with an average of 7 alleles per locus, and their polymorphism information content ranged between 0.424 and 0.769, with an average of 0.569. The analysis of molecular variance revealed that genetic variation within the individuals accounted for 94 % of the total variation, inditing that the variation of A. sinensis is derived from individual variation. Furthermore, the structure analysis indicated that the natural populations of A. sinensis could be theoretically divided into 16 subgroups. The 16 polymorphic SSRs had strong cross–species transferability and distinguished individuals of A. agallochum (Lour.) Roxb. ex Finl. and A. malaccensis Lam. Taken together, these findings provide a useful resource for germplasm identification and molecular marker–assisted breeding of A. sinensis.

Variation in the Photosynthetic Leaf Pigments of Different Basil (Ocimum spp.) Genotypes under Varying Conditions at the Flowering Stage

Basil is a culinary herb in high demand all year round, either fresh, dried, or frozen. Field basil crops are commercially predominant, while greenhouse crops can cover the demand for fresh basil during the off-season. The leaf aspect of basil has great importance for the food industry, and a great diversity of genotypes has been created. The aim of this research was to conduct a comparative characterization of 12 basil genotypes (green and purple leaf) that present interest for breeding programs from a national germplasm collection. The study examines the accumulation of photosynthetic pigments in basil cultivated in field versus greenhouse conditions as indicators of plant performance and herb quality from the perspective of ensuring fresh plant material all year round. The experimental median indicated that photosynthetic leaf pigments accumulated in higher concentrations in the field relative to the greenhouse conditions, in descending order: β-carotene, lutein, chlorophyll a, and chlorophyll b. The trend was not as consistent for chlorophyll b, since four out of twelve genotypes presented higher levels in the greenhouse than in the field, while the overall values were not much lower in the greenhouse than the field (16.82%). All genotypes accumulated much higher carotenoid contents in field conditions relative to greenhouse conditions (>200%) and could also provide better nutritional advantages given their demonstrated health benefits. The differences in photosynthetic leaf pigments have both nutritional (the carotenoids), shelf-life, and processing relevance (chlorophylls) and serve as quality markers.

Resilient Response to Combined Heat and Drought Stress Conditions of a Tomato Germplasm Collection, Including Natural and Ethyl Methanesulfonate-Induced Variants

Agricultural systems are currently facing significant issues, primarily due to population growth rates in the context of global climate change. Rising temperatures cause plant heat stress and impact crop yield, which in turn compromises global food production and safety. Climate change is also having a significant impact on water availability around the world, and droughts are becoming more frequent and severe in many regions. The combined effect of both heat and drought stresses increases plant damage, resulting in reduced plant development and productivity loss. Therefore, developing heat–drought-tolerant crop varieties is crucial for enhancing yield under these challenging conditions. Tomato (Solanum lycopersicum L.), a major vegetable crop highly appreciated for its nutritional qualities, is particularly sensitive to extreme temperatures, which have a significant negative impact on tomato fruit setting and cause male gametophyte abortion. In this work, a classical genetic approach was employed to identify tomato genotypes showing a resilient response to combined heat and drought stress conditions. A phenotype screening of a natural germplasm collection and an ethyl methanesulfonate (EMS) mutagenized population resulted in the identification of a significant number of tomato lines tolerant to combined heat and drought conditions, specifically 161 EMS lines and 24 natural accessions as tolerant. In addition, TILLING and Eco-TILLING analyses were used as proof-of-concept to isolate new genetic variants of genes previously reported as key regulators of abiotic stress responses in different species. The identification of these variants holds the potential to provide suitable plant material for breeding programs focused on enhancing tomato resilience to adverse climate conditions.

Genome-wide association studies reveal stable loci for wheat grain size under different sowing dates.

Wheat (Tritium aestivum L.) production is critical for global food security. In recent years, due to climate change and the prolonged growing period of rice varieties, the delayed sowing of wheat has resulted in a loss of grain yield in the area of the middle and lower reaches of the Yangtze River. It is of great significance to screen for natural germplasm resources of wheat that are resistant to late sowing and to explore genetic loci that stably control grain size and yield. A collection of 327 wheat accessions from diverse sources were subjected to genome-wide association studies using genotyping-by-sequencing. Field trials were conducted under normal, delayed, and seriously delayed sowing conditions for grain length, width, and thousand-grain weight at two sites. Additionally, the additive main effects and multiplicative interaction (AMMI) model was applied to evaluate the stability of thousand-grain weight of 327 accessions across multiple sowing dates. Four wheat germplasm resources have been screened, demonstrating higher stability of thousand-grain weight. A total of 43, 35, and 39 significant MTAs were determined across all chromosomes except for 4D under the three sowing dates, respectively. A total of 10.31% of MTAs that stably affect wheat grain size could be repeatedly identified in at least two sowing dates, with PVE ranging from 0.03% to 38.06%. Among these, six were for GL, three for GW, and one for TGW. There were three novel and stable loci (4A_598189950, 4B_307707920, 2D_622241054) located in conserved regions of the genome, which provide excellent genetic resources for pyramid breeding strategies of superior loci. Our findings offer a theoretical basis for cultivar improvement and marker-assisted selection in wheat breeding practices.

Uncovering key salt-tolerant regulators through a combined eQTL and GWAS analysis using the super pan-genome in rice.

For sessile plants, gene expression plays a pivotal role in responding to salinity stress by activating or suppressing specific genes. However, our knowledge of genetic variations governing gene expression in response to salt stress remains limited in natural germplasm. Through transcriptome analysis of the Global Mini-Core Rice Collection consisting of a panel of 202 accessions, we identified 22 345 and 27 610 expression quantitative trait loci associated with the expression of 7787 and 9361 eGenes under normal and salt-stress conditions, respectively, leveraging the super pan-genome map. Notably, combined with genome-wide association studies, we swiftly pinpointed the potential candidate gene STG5-a major salt-tolerant locus known as qSTS5. Intriguingly, STG5 is required for maintaining Na+/K+ homeostasis by directly regulating the transcription of multiple members of the OsHKT gene family. Our study sheds light on how genetic variants influence the dynamic changes in gene expression responding to salinity stress and provides a valuable resource for the mining of salt-tolerant genes in the future.

Characterization of mono‐varietal virgin olive oils obtained from Turkish National Germplasm Bank according to fatty acid composition, volatile profile, and sensory properties

AbstractMono‐varietal virgin olive oils were obtained from Olea europaea L. olives grown in the National Olive Germplasm Bank in the same agronomic conditions for two harvesting years. Samples were characterized according to fatty acid composition, volatile profile, and sensory attributes, and varieties were compared using Pearson correlation, principal component analysis (PCA), and cluster analysis. Odor activity values (OAVs) of the volatiles were calculated to discuss relationships between individual sensory properties and volatiles. Although most of the samples overlapped on the score plots, some samples were located away from the others. The sample groupings on the dendrogram plotted using Ward's linkage were generally suitable with PCA results. Ethanol had a negative correlation with 9 out of 14 pleasant attributes. According to OAVs, trans‐2‐hexenal content had the most important effect on sensory attributes and positively correlated with flower odor, whereas hexenal content contributed to sweet attributes. Similarly, the effect of 1‐hexanol content strengthened the flower attribute but weakened the bitter taste. These findings were also confirmed by separating some varieties rich in those volatiles on the PCA bi‐plot of sensory attributes. Samples were grouped on a dendrogram in accordance with total ester and total C3, C5, and C6 acid contents.Practical Application: Most olive production in Turkey is based on a few varieties, whereas 95 different endemic varieties were registered by Turkish National Germplasm Bank. This study provides information on the volatile composition, sensory profile, and fatty acid composition of virgin olive oils produced from some rare varieties with high oil content. Moreover, relationships and correlations between individual volatiles and sensory attributes were evaluated, and the main differences in fatty acid composition, volatile profile, and sensory attributes of these Turkish virgin olive oils and those produced from well‐known varieties from major producing countries were compared. Thus, data on the main characteristics of extra virgin olive oils produced from Turkish olives were provided to the literature, these varieties were promoted internationally, and their cultivation was encouraged.

Wild relatives of potato (Solanum L. sec. Petota) poorly sampled and unprotected in Colombia

AbstractWild potato relatives (Solanum L. sec. Petota) play a vital role in crop improvement, understanding crop evolution, and conserving potato diversity. However, these invaluable resources are often neglected and underutilized and are susceptible to threats such as climate change, urbanization, and agricultural expansion. Little is known about the diversity, conservation status, and distribution of wild potato species in Colombia. To address this gap, we assessed the conservation status of five wild potato relatives conserved in the ex situ Colombian Central Collection. Five species were analyzed for their spatial patterns of biodiversity, conservation status, and conservation gaps. Colombia was found to have six centers of species richness, four areas of endemism, and six biogeographical regions. Of the five native species, only one was classified as adequately conserved for ex situ conservation, while the other four were considered low priority. In contrast, for in situ conservation, three species showed high priority, one was classified as medium priority, and one as low priority. In light of these findings, we propose three conservation strategies: (1) conducting collection missions to increase accessions in the national germplasm bank, prioritizing high‐priority species; (2) identifying and protecting unprotected natural habitats and engaging stakeholders to enhance in situ conservation efforts; and (3) establishing regional community genebanks to ensure localized conservation efforts.

Efforts to cryopreserve shrimp (Penaeid) genetic resources and the potential for a shrimp germplasm bank in the United States

Shrimp are an important global protein source and the most consumed seafood in the United States. Despite the importance of shrimp to the United States and to global food production, genetic diversity and germplasm preservation has not received critical attention. At this time, shrimp genetic resources have not been added to the USDA National Animal Germplasm Program gene bank in the United States. Here we summarize the importance of shrimp genetic resources to US and global food production and describe the need for shrimp germplasm cryopreservation. We also describe past and current research efforts to cryopreserve shrimp germplasm in the forms of embryos, larvae, and spermatophores. While early work has focused on protocol development, these protocols have not been successfully implemented on a commercial scale. It has also not been documented that cryopreserved larvae can reach reproductive maturity. Therefore, additional research and stakeholder efforts are needed to develop and validate larval cryopreservation methods capable of producing larvae reaching reproductive maturity. Finally, we discuss the necessary material needed to establish a shrimp germplasm collection in the USDA repository. We describe the numbers of larvae or families needed to reconstitute a breeding population given varying levels of cryopreservation success. Early work relating to shrimp germplasm cryopreservation is laying the foundation for the successful cryopreservation of larvae and spermatophores as well as the establishment of a national germplasm bank for shrimp larvae within the United States.

Genetic analysis of the variation for mineral accumulation in the leaves and seeds of natural germplasm of Brassica rapa L. (AA) and the its derived forms extracted from an allotetraploid B.juncea L.(AABB)

Brassica rapa L. (2n = 20; AA) is a vegetable and oilseed crop that is grown all over the world. Its leaves, shoots, and seeds store significant amounts of minerals. We used inductively coupled plasma-optical emission spectroscopy (ICP-OES) to determine the concentrations of eleven minerals in the leaves and seeds of 195 advanced generation inbred lines, of which 92 represented natural (NR) B. rapa and the remaining 103 were derived (DR) from a set of mother genotypes originally extracted from an allotetraploid B. juncea (2n = 36; AABB). The inbred lines differed for the composition of leaf and seed minerals. Leaf concentrations of N, K, Zn, and Se were higher in the DR subpanel as compared to NR subpanel, along with high seed accumulations of K and Se. DArT genotyping and genome wide association mapping led to the identification of SNPs associated with leaf and seed mineral compositions. Chromosomes A03, A05, and A10 harboured the most associated loci. Annotations of the regions adjacent to respective GWAS peaks allowed prediction of genes known for acquisition, transport, and accumulation of minerals and heavy metal detoxification. Transcriptome analysis revealed differential expression patterns of the predicted candidates, with most genes either down-regulated in derived genotypes relative to natural forms or their expression being comparable between the two. General downregulation may be a consequence of extracting B. rapa from allotetraploid B. juncea through genome resection. Some of the identified SNPs may be used as DNA markers for breeding programmes designed to modify the leaf and seed mineral compositions.

Screening the Citrus Greek National Germplasm Collection for fruit quality and metabolic footprint

Citrus fruits are one of the most important fruits in the global food industry due to their unique taste and nutritional benefits. Herein, we characterize the physicochemical and bioactive attributes of twenty-nine Greek citrus accessions, including oranges, mandarins/clementines, lemons, bergamot, citrons and lime along with twenty-seven highly commercial international cultivars. The assessed genotypes differ in various quality traits including color, ripening, and textural attributes. Several indigenous cultivars displayed desirable organoleptic traits, such as the oranges ‘Valencia Oval Porou’ (e.g., juice content and ascorbic acid) and ‘Sanguine Gouritis’ (eg., soluble solids (SSC) and acidity (TA) ratio), the mandarin ‘Clementine Porou’ (e.g., SSC/TA) and the lemon ‘Vakalou’ (e.g., firmness, acidity). Differences in primary metabolites, mainly in sugars, organic acids and amino acids were recorded among the tested species and cultivars. In addition, the autochthonous orange cultivars ‘Sanguine Gouritsis’ and ‘Valencia Oval Porou’ contained high sucrose levels whereas ‘Lainato Chanion’ had high hesperidin content. This large-scale analysis supports the ample availability of genetic resources for the development of citrus cultivars with improved nutritional quality traits.

Spontaneous movement of a retrotransposon generated genic dominant male sterility providing a useful tool for rice breeding.

Male sterility in plants provides valuable breeding tools in germplasm innovation and hybrid crop production. However, genetic resources for dominant genic male sterility, which hold great promise to facilitate breeding processes, are extremely rare in natural germplasm. Here we characterized the Sanming Dominant Genic Male Sterility in rice and identified the gene SDGMS using a map-based cloning approach. We found that spontaneous movement of a 1978-bp long terminal repeat (LTR) retrotransposon into the promoter region of the SDGMS gene activates its expression in anther tapetum, which causes abnormal programmed cell death of tapetal cells resulting in dominant male sterility. SDGMS encodes a ribosome inactivating protein showing N-glycosidase activity. The activation of SDGMS triggers transcription reprogramming of genes responsive to biotic stress leading to a hypersensitive response which causes sterility. The results demonstrate that an ectopic gene activation by transposon movement can give birth to a novel trait which enriches phenotypic diversity with practical utility.

Genetic fingerprint construction and genetic diversity analysis of sweet potato (Ipomoea batatas) germplasm resources

BackgroundChina is the largest producer of sweet potato in the world, accounting for 57.0% of the global output. Germplasm resources are the basis for promoting innovations in the seed industry and ensuring food security. Individual and accurate identification of sweet potato germplasm is an important part of conservation and efficient utilization.ResultsIn this study, nine pairs of simple sequence repeat molecular markers and 16 morphological markers were used to construct genetic fingerprints for sweet potato individual identification. Combined with basic information, typical phenotypic photographs, genotype peak graphs, and a two-dimensional code for detection and identification were generated. Finally, a genetic fingerprint database containing 1021 sweet potato germplasm resources in the “National Germplasm Guangzhou Sweet Potato Nursery Genebank in China” was constructed. Genetic diversity analysis of the 1021 sweet potato genotypes using the nine pairs of simple sequence repeat markers revealed a narrow genetic variation range of Chinese native sweet potato germplasm resources, and Chinese germplasm was close to that from Japan and the United States, far from that from the Philippines and Thailand, and the furthest from that from Peru. Sweet potato germplasm resources from Peru had the richest genetic diversity, supporting the view that Peru is the center of origin and domestication of sweet potato varieties.ConclusionsOverall, this study provides scientific guidance for the conservation, identification, and utilization of sweet potato germplasm resources and offers a reference to facilitate the discovery of important genes to boost sweet potato breeding.

Estimating genetic diversity among durum wheat (Triticum durum desf.) landraces using morphological and SRAP markers

The durum wheat (Triticum turgidum L. ssp. durum Desf.) Landraces are a valuable source of natural germplasm for enhancing the genetic diversity of existing durum wheat cultivars. The study analyzed the genetic diversity of twenty-two durum wheat landraces including eight local Saudi landraces and fourteen introduced landraces using sixteen morphological descriptors and sequence-related amplified polymorphism (SRAP) markers. The results showed significant differences between the analyzed agro-morphological parameters and a large degree of genetic variation across the tested landraces. Principle components analysis (PCA) was used to determine agro-morphological relationships among different traits. The first six principal components (PCs) accounted for 78.47 % of the cumulative variability among 22 landraces. The PC1demonstrated variability in coleoptile anthocyanin coloration, straw pith, culm neck glaucosity, flag leaf glaucosity, ear glaucosity, and length of awn at tip relative to length of ear. Wheat landraces (L8, L14, L497, L569, L590, L594, L600, L601, and L602) showed increased diversity in dry region and contributed to PC1. A couple landraces had higher plant height (L12, L598, and L654), heading days (650, 656), and ear length (L12, L594, and L650) respectively. The dendrogram generated from the standardized morphological data separated the twenty-two durum wheat genotypes mainly into two clusters. The landraces 14, 600 and 602 grouped into separate cluster with strong correlation to ear glaucosity. Genetic diversity of these landraces was also evaluated using eight SRAP markers, with 482 amplified fragments and an average polymorphic information content (PIC) of 0.27. The dendrogram based on SRAP markers separated into two clusters with some diversified landraces (L8, 594, 602, 977, and L650). The Mantel test found no significant correlation (phenotypic or genetic) between 22 wheat durum landraces (r = 0.013, p = 0.84, =0.05). The results demonstrated the power of morphological and SRAP markers for detecting diversity among durum wheat landraces in the semi-arid region of Saudi Arabia. Thus, study provides insights into wheat diversity for better in-situ and ex-situ conservation and paves the road for their use in a Saudi durum wheat breeding program.

First Report of Fusarium citri Causing Postharvest Fruit Rot of Chayote in Mexico.

In November 2018, symptoms of brown rot were observed on chayote (Sechium edule) var. nigrum spinosum with a 20% disease incidence of 120 harvested fruits in the National Germplasm Bank of Sechium edule, located in the Centro Regional Universitario Oriente (CRUO) from the Chapingo Autonomous University (Huatusco, Veracruz, Mexico). For fungal isolation, pieces from symptomatic fruits were surface disinfected by immersion in a 1.5% NaClO solution for 2 min, rinsed in sterile distilled water, placed in Petri plates containing potato dextrose agar (PDA) amended with kanamycin sulfate, and incubated at 25ºC. Fusarium-like colonies were consistently isolated on PDA and five monoconidial isolates were obtained. A representative isolate was selected for morphological characterization, phylogenetic analysis, and pathogenicity tests. On PDA, colonies exhibited white and fluffy aerial mycelia, with diffused pale brown pigment in the center at 7 days of incubation at 25℃ in darkness. Macroconidia (n= 100) were hyaline, falcate, with 4 to 5 septa, measuring 23.9 to 31.9 × 2.9 to 4.2 μm, and foot-shaped basal cells. Microconidia and chlamydospores were absent. Morphological features were consistent with the description of the Fusarium incarnatum-equiseti species complex (Xia et al. 2019). The isolate was deposited as FUS2 in the Culture Collection of Phytopathogenic Fungi of the Laboratory of Plant Pathology at the Colegio de Postgraduados. For molecular identification, genomic DNA was extracted, and the internal transcribed spacer (ITS) region, partial sequences of translation elongation factor 1-alpha (EF1-α), and the second-largest subunit of RNA polymerase II (rpb2) genes were amplified, and sequenced with the primer sets ITS5/ITS4 (White et al. 1990), EF1-728F/EF1-986R (Carbone and Kohn 1999), and RBP2-5F/RPB2-7R (Liu et al. 1999), respectively. DNA sequences were edited in BioEdit 7.2 and compared with those in the NCBI nucleotide database. Alignments were implemented in MEGA X using reference sequences from Fusarium spp. A phylogenetic tree, including published ITS, EF1-α, and rpb2 sequence data, was constructed for the Fusarium incarnatum-equiseti species complex (FIESC) based on Maximum Likelihood. The sequences were deposited in GenBank (accession nos. ON878083, ON890421, and ON890420). The phylogenetic analysis grouped the isolate FUS2 within the F. citri clade. Pathogenicity of the fungus was verified on 10 healthy chayote fruits var. nigrum spinosum previously disinfested by immersion in a 1% NaClO solution for 3 min and washed in sterile water. A total of 5 mL of a conidial suspension (1 × 106 spores/ml) was sprayed on each whole fruit. Ten control fruit were sprayed with sterile distilled water. The fruits were kept in a moist plastic chamber at 25°C and 12 h light/dark for 30 days. All inoculated fruits developed water-soaked brown lesions (3 to 5 cm in diameter) covered with white mycelium at 15 days after inoculation, whereas no symptoms were observed on the control fruits. The fungus was consistently re-isolated only from the diseased fruits and found to be morphologically identical to the isolate used for inoculation, fulfilling Koch´s postulates. Fusarium citri has been associated with Capsicum sp. and mandarin orange in China, Triticum sp. in Iran, alfalfa in Denmark, and lettuce in the Czech Republic and Italy (Farr and Rossman 2022). To our knowledge, this is the first report of F. citri causing postharvest fruit rot of chayote in Mexico and worldwide.

Seed-specific expression of the class 2 Phytoglobin (Pgb2) increases seed oil in Brassica napus

To examine the function of phytoglobin 2 (Pgb2) on seed oil level in the oil-producing crop Brassica napus L., we generated transgenic plants in which BnPgb2 was over-expressed in the seeds using the cruciferin1 promoter. Over-expression of BnPgb2 elevated the amount of oil, which showed a positive relationship with the level of BnPgb2, without altering the oil nutritional value, as evidenced by the lack of major changes in composition of fatty acids (FA), and key agronomic traits. Two key transcription factors, LEAFY COTYLEDON1 (LEC1) and WRINKLED1 (WRI1), known to promote the synthesis of fatty acids (FA) and potentiate oil accumulation, were induced in BnPgb2 over-expressing seeds. The concomitant induction of several enzymes of sucrose metabolism, SUCROSE SYNTHASE1 (SUS) 1 and 3, FRUCTOSE BISPHOSPHATE ALDOLASE (FPA), and PHOSPHOGLYCERATE KINASE (PGK), and starch synthesis, ADP-GLUCOSE PHOSPHORYLASE (AGPase) suggests that BnPgb2 favors sugar mobilization for FA production. The two plastid FA biosynthetic enzymes SUBUNIT A OF ACETYL-CoA CARBOXYLASE (ACCA2), and MALONYL-CoA:ACP TRANSACYLASE (MCAT) were also up-regulated by the over-expression of BnPgb2. The requirement of BnPgb2 for oil deposition was further evidenced in natural germplasm by the higher levels of BnPgb2 in seeds of high-oil genotypes relative to their low-oil counterparts.

Prioritizing Colombian plant genetic resources for investment in research using indicators about the geographic origin, vulnerability status, economic benefits, and food security importance

Germplasm banks are the most significant repository for plant genetic resources for food and agriculture (PGRFA) worldwide. Despite their strategic importance, national germplasm banks of tropical megadiverse developing countries such as Colombia have extremely limited funds. Therefore, making strategic decisions about research investment is essential. Here, we designed a data-driven approach to build an index that sorts Colombian PGRFA into three groups: high, medium, or low priority, based on four pillars of information from open-access databases and aligned with the sustainable goals of no poverty and zero hunger: Geographic origin, vulnerability status, economic benefits, and food security importance. We analyzed 345 PGRFA using the index, separating them into two groups, 275 already conserved in the Colombian germplasm bank (BGVCOL group) and 70 not currently conserved in the BGVCOL (NCB group). We used fuzzy logic to classify each PGRFA by each pillar and integrate it to obtain a priority index. Missing data for native crops were frequent in the BGVCOL group. Therefore we adopted an imputation strategy to fill the gaps and calculated the uncertainty. After applying the index, PGRFA with higher priority were 24 (8.72%) from the BGVCOL (i.e., 15 potatoes, three tomatoes, two tree tomatoes, pineapple, cocoa, papaya, and yacon) and one from NCB (i.e., coffee). We concluded that this methodology successfully prioritized PGRFA in Colombia and shows the big holes of knowledge for future research and alternatives to improve this index. The versatility of this methodology could be helpful in other genebanks with budget limitations for research investment.

Characterization of morpho-phenological traits in the traditional landraces of rice

The landraces of rice provide a wide range of genetic variations and environmental adaptation and act as excellent genetic resources for crop improvement. Natural germplasm that has been maintained through conservation is in desperate need of rigorous investigation in order to uncover new genes or alleles to introduce into rice breeding programmes. Given this context, an investigation was done to determine the degree of genetic divergence and variability across 31 rice landraces for various productivity, physiological, and grain quality traits. On evaluation of the mean performance of landraces and the influence of characters in genetic divergence resulted in the identification of better landraces viz., Vellaikuruvikar, Karupu Kavuni, Kichidi Samba and Athur Kichadi which are better for both grain yield and quality traits that can be used to create better recombinants, by hybridization. These gene pools could be used in selective breeding to significantly enhance the agronomic characters. Out of 20 traits that were investigated,15 traits viz., height of the plant, productive tillers per plant, length of panicle, spikelets per panicle, filled grains per panicle, grain yield per plant, seedling root to shoot ratio, harvest index, head rice recovery, length of the kernel, length to breadth ratio of kernel, breadth of kernel after cooking, length to breadth ratio of kernel after cooking, gelatinization temperature and aroma were noted for high heritability and genetic advancement suggesting that additive gene action predominates, there by opening up a wide range of opportunities for these traits to be improved through simple phenotypic selection. Keywords: Rice, landraces, GCV, PCV, heritability, PCA

Heterologous expression of SpsLAZY1a in Populus enhanced the sensitiveness of plant architecture

Plant tiller angle is a key agronomic trait that contributes to ideal plant architecture and grain production. However, the molecular mechanism regulating branch angle and plant architecture has not been fully explored in Salix psammophila. Here, we found that the natural germplasm of S. psammophila has a different plant architecture and determined that SpsLAZY1a participated in the control of agronomical traits. SpsLAZY1a was mainly expressed in the stem. SpsLAZY1a transformed with heterologous overexpression in poplar caused distortion at the base of the stem, increased the number of branches and influenced the sensitivity to gravity of the plant. Furthermore, SpsLAZY1a overexpression plants accumulated less auxin and cytokinin than the control. Transcriptome sequencing showed that the overexpression of SpsLAZY1a caused the differential expression of related genes in the plant hormone signal transduction, starch and sucrose metabolism pathways. The expression level of SpsLAZY1a can be rapidly induced by auxin. Taken together, we discovered the key genes related to S. psammophila plant architecture, which provided a basis for further research on the development of tree architecture.

Over-expression of the barley Phytoglobin 1 (HvPgb1) evokes leaf-specific transcriptional responses during root waterlogging

Oxygen deprivation (hypoxia) in the root due to waterlogging causes profound metabolic changes in the aerial organs depressing growth and limiting plant productivity in barley (Hordeum vulgare L.). Genome-wide analyses in waterlogged wild type (WT) barley (cv. Golden Promise) plants and plants over-expressing the phytoglobin 1 HvPgb1 [HvPgb1(OE)] were performed to determine leaf specific transcriptional responses during waterlogging. Normoxic WT plants outperformed their HvPgb1(OE) counterparts for dry weight biomass, chlorophyll content, photosynthetic rate, stomatal conductance, and transpiration. Root waterlogging severely depressed all these parameters in WT plants but not in HvPgb1(OE) plants, which exhibited an increase in photosynthetic rate. In leaftissue, root waterlogging repressed genes encoding photosynthetic components and chlorophyll biosynthetic enzymes, while induced those of reactive oxygen species (ROS)-generating enzymes. This repression was alleviated in HvPgb1(OE) leaves which also exhibited an induction of enzymes participating in antioxidant responses. In the same leaves, the transcript levels of several genes participating in nitrogen metabolism were also higher relative to WT leaves. Ethylene levels were diminished by root waterlogging in leaves of WT plants, but not in HvPgb1(OE), which were enriched in transcripts of ethylene biosynthetic enzymes and ethylene response factors. Pharmacological treatments increasing the level or action of ethylene further suggested the requirement of ethylene in plant response to root waterlogging. In natural germplasm an elevation in foliar HvPgb1 between 16h and 24h of waterlogging occurred in tolerant genotypes but not in susceptible ones. By integrating morpho-physiological parameters with transcriptome data, this study provides a framework defining leaf responses to root waterlogging and indicates that the induction of HvPgb1 may be used as a selection tool to enhance resilience to excess moisture.

THE QUALITATIVE OENOLOGICAL POTENTIAL OF THE WINE GRAPECULTIVARS FROM THE AMPELOGRAPHIC COLLECTION AT SCDVV DRĂGĂŞANI

Research was carried out during 2020-2022 period at SCDVV Drăgăşani and at the Wine Analysis Laboratory within Sâmbureşti Domains. The cultivars analyzed and studied were 'Negru vârtos', 'Novac', 'Cârlogancă' and 'Bikaver 13', from the national germplasm collection of the Drăgăşani unit. The first three cultivars are considered autochthonous and even local, the fourth is a Hungarian cultivar. These cultivars are valuable, which lend themselves best to the eco-pedological conditions of the wine-growing area. The qualities of the wines obtained from these cultivars were valued, through physical-chemical analyzes and statistical calculations, using indices such as mean, variance (s2), standard deviation (s) and the coefficient of variation (CV%), the aim being to obtain wines of the DOC type and GI and their promotion on the national and international wine market. Therefore, the wines from Drăgăşani continue their traditional performance even today, that of being present on the market with their famous and very good wines. Drăgăşani wines are known in the country and abroad, being appreciated among the best red and white wines.