Genetic Resources and Crop Evolution最新文献

The aim of this study was to assess the genetic diversity and population structure of 94 common walnut germplasm resources from different provinces in China using simple sequence repeat (SSR) markers. The 10 pairs of simple sequence repeat (SSR) primers amplified a total of 137 clearly identifiable loci, with an average of 13.7 loci per marker. The mean values of observed number of alleles (Na), effective number of alleles (Ne), Nei’s diversity index (H), Shannon’s information index (I), and polymorphism information content (PIC) of the primers were 1.997, 1.295, 0.197, 0.327, and 0.504, respectively. Genetic relationship analysis was performed by principal coordinate analysis (PCoA) and neighbour-joining cluster analysis (NJ) to classify germplasm into 3 and 11 groups. Germplasm from different regions was interspersed in the groups, suggesting that there was also a certain degree of kinship between germplasm resources from different regions. All germplasms were divided into two populations by structural analysis, and there was low genetic differentiation between them, suggesting relatively narrow resource utilization and a relatively low genetic base of cultivars in breeding units over time. The above results indicated that the DNA clustering of walnut germplasm is not related to its geographical origin but rather to its genetic relationship, suggesting the complexity of the genetic background of walnut germplasm. These findings provide a theoretical basis for further rational use of walnut germplasm resources and for breeding new walnut cultivars with exceptional traits.

Five Selenicereus species are well-known in the fruit market as dragon fruit, pitahaya, or pitaya. Native to the New World, pitahayas are considered underutilized crops with nutraceutical properties and easily propagated with a distribution that could potentially be extended to dry climates. Our goal is to understand the relationships of wild and cultivated populations and to determine genetic variation in a spatial scenario to discover hotspots of haplotype and genetic variation that will allow the conservation of valuable germplasm, as well as crop wild relatives. Sampling consisted of 170 individuals for three plastid molecular markers comprising the five cultivated species and as outgroups populations of four closely related species were included in the haplotype analyses. Genealogical relationships were determined, along with genetic variation in spatial patterns. The majority of the haplotypes were shared among the nine species in a geographic pattern; however, distant populations of different species also shared haplotypes. Selenicereus monacanthus displayed the highest genetic variation; its haplotype network is complex and intricate, probably related to the management to which the populations have been subjected, in which certain attributes suitable for cultivation and valuable for the fruit market have been selected. Historical evidence suggests that S. undatus has been cultivated in home gardens in the Maya area since pre-Columbian times, and the highest genetic diversity was found there. Conservation of wild crop relatives is important to preserve underutilized crops, therefore southern Mexico and northern Central America are the most relevant regions to protect genetic diversity of pitahayas.

This study aimed to determine the karyological characteristics, DNA content, and agro-morphological plant characteristics of Vicia cassia Boiss. and Vicia aintabensis Boiss. & Hausskn. collected from natural flora of Turkiye. The results were also compared with those of Vicia sativa. The main stem length, the numbers of main stem branches per plant, the number of leaves of main stem, the number of leaflets per leaf, the number of grains per pod, the pod width and length as well as thousand seed weight characteristics showed significant variation across the species, with the exception of 50% inflorescences (p < 0.4987) and natural plant heights (p < 0.3276). Karyotype formulas of Vicia cassia, V. aintabensis and V. sativa were determined as 2n = 2x = 14 = 3 m + 1t^sat + 1sm + 2t, 2n = 2x = 14 = 1sm + 4st + 2t, and 2n = 2x = 12 = 5st + 1 m, respectively. The genome size of V. aintabensis (17,227.47 Mbp) was 5.26 and 5.01 times larger than V. cassia (3273.85 Mbp) and V. sativa (3435.22 Mpb), respectively. The importance of the karyomorphological data was also evaluated with the morphological evidences.

Guava is one of the important commercial fruit crops of India, but its production suffers from wilt and nematode complex infection. Thus, screening of wild species resulted in the identification of Psidium cattleianum as one of the sources of resistance. Involving resistant source, interspecific hybrids were developed using ‘Arka Poorna’ and ‘H 12-5’ (Psidium guajava) as the female parents with P. cattleianum var. cattleianum and P. cattleianum var. lucidum as the male parents. In the present study, previously identified 42 resistant interspecific hybrids were characterized based on morphological, molecular and biochemical (phenolic acid and volatile profiling) traits in comparison with their parents at vegetative stage. Among 15 morphological traits, leaf traits viz., leaf blade shape was obovate in eight progenies and leaf base shape was obtuse in 27 progenies resembling male parent. As regards leaf tip, acute shape was found in 35 progenies resembling to P. cattleianum (male parent) and this trait could act as a morphological marker for the identification of hybrid progenies at vegetative stage. The molecular markers (simple sequence repeats, SSR), mpgCIR220 and mpgCIR253 were highly reproducible and could effectively confirmed the hybridity of interspecific hybrid progenies of P. cattleianum var. lucidum and P. cattleianum var. cattleianum, respectively. In addition to morphological and molecular markers, the levels of few volatile compounds viz., β-borbonene, aristolene, (E, Z)-alpha-Farnesene, trans-gamma-bisabolene, neryl acetate, linalyl acetate and furan, 2-ethyl, were similar to those of their male parents. These novel volatiles, morphological traits and molecular markers can be used to enhance the speed of breeding by reducing time for progeny identification.

Sesame crop is susceptible to phyllody disease caused by phytoplasma leading to major yield losses across India and worldwide. Screening of sesame genotypes against phyllody is essential to identify reliable sources of resistance. The experiments were conducted in phyllody hot spot research field with different dates of sowing in 2018–2019 to identify the effective season for screening against sesame phyllody and durable source of resistance. The results from our study recorded that phyllody incidence was more prevalent during July sowings when compared to November, August and January. Furthermore, field screening for continuous three years (2019–2021) recorded phyllody tolerance in three sesame genotypes (GTG-30, G-10-P1-P5-P3 and G-10-P1-P5-P6) along with resistant check GT-10. Sesame genotype, RJR-170 was found to be highly susceptible among all genotypes. The leafhopper population ranged from 0.2 to 0.3 among genotypes showing tolerance. Our findings could be successfully exploited in phyllody resistant breeding programmes.

The Dolichos bean (Lablab purpureus L.), despite its rich history, diverse applications and impressive nutritional profile, faces limitations in adoption and productivity. This review highlight its potential for sustainable food security due to its genetic diversity, adaptability and nitrogen fixation, while acknowledging challenges like low awareness and restricted breeding programs. Collaborative efforts across research and practice are crucial to overcome these hurdles. Modern technologies like gene editing and omics approaches offer exciting prospects for improved stress tolerance and host plant resistance to pathogens and pests. Future research should focus on exploring genetic diversity, enhancing nutritional quality, developing sustainable cropping systems and leveraging biotechnological tools to develop climate resilient cultivars with higher production and improved nutrition. Ultimately, increasing awareness of the Dolichos bean benefits can foster wider adoption and support its sustainable use for food, feed and various value-added products across diverse regions.

Great genetic variation in bermudagrass [Cynodon dactylon (L.) Pers.] make it adapt to various environment of widely distributed regions and present valuable wild germplasm for turfgrass breeding. Understanding geographic distribution of genetic diversification of bermudagrass along latitudinal and longitudinal gradients is favor of assessing genetic variation and diverse germplasm conservation. The study explored genetic variability and phylogeographic structure of 28 populations using three chloroplast intergenic spacer regions sequences. Bermudagrass populations at different latitudes exhibited a high level of genetic differentiation from populations at different longitudes. Populations at different latitudes indicated higher gene flow than populations at different longitudes, which attributed to higher genetic variation within population along the latitudinal gradient than longitudinal gradient. Contrast to apparent phylogeographic structure in populations along the latitudinal gradient, majority haplotypes sharing occurred in populations along the longitudinal gradient. Populations at high-latitudes showed distinct genetic diversity and haplotypes from populations at mid-latitudes. The Dabieshan and Nanling Mountains acted as the geographic barriers along the latitudinal gradient, leading to the intraspecific phylogeographic subdivision and divergence. Our study is valuable to better set up evolutionary significant units and formulate appropriate strategies for conserving genetic resources of bermudagrass.

The legitimacy of 13 hybrid families resulting from crosses via manual pollination techniques was studied using single nucleotide polymorphism (SNP) markers. The aim of this study was to ensure the conformity of offspring resulting from simple crosses. Fifty-one individuals (39 descendants and 12 parent clones) were analysed using 84 SNP markers. The results revealed nonsignificant genetic differentiation between parents and progenies (P = 0.323). High allelic richness was also revealed, with the average number of alleles per locus ranging from 1.57 to 1.92, with an average of 1.77 in offspring and 2 in parents. Thus, 1% of the total variance was attributed to interpopulation variance, and 99% was attributed to intrapopulation variance. Low genetic differentiation (FST < 0.05) and genetic distances (0.03 < D < 0.09) were observed between hybrid families F2, F8, F10, F11, F12, F13 and F14 and their respective parents. These results confirm the legitimacy of the hybrids produced and suggest that the manual pollination work carried out at CNRA sites is reliable for faithfully reproducing hybrid material using known parents.

Oleaceae (olive family), includes 28 genera and about 700 species. Nevertheless, there remains a lot to uncover about the group’s historical development, the evolution of various reproductive and dispersal mechanisms, and polyploidization episodes appear to be linked to its diversification. In the current study, foliar epidermal anatomy of 13 plant species and 2 varieties from 7 genera of Oleaceae was examined under a light microscope. The qualitative and quantitative features like stomatal density, size,shape of guard cell, number of epidermal cell, subsidiary cells, and structure and density of trichomes were analysed using a light microscope. This was the first study on the foliar micromorphology of various Oleaceae taxa. Almost all species exhibited hypostomatic type except one in which Amphistomatic type was observed. Most of the stomata were anomocytic while some Paracytic and one diacytic stomata were also seen. Maximum stomatal length of (30.80 + 1.44 μm) and lowest of (18.30 + 0.21 μm) was noted. All trichomes observed were unicellular. Both glandular and non-glandular trichomes were observed with highest trichome length (237.75–248.00 = 242.25 + 1.73 μm) and the lowest (100.00–101.75 = 100.75 + 0.32 μm). Plant taxonomists might commence their future research with the micro-morphological aspects of foliar epidermal morphology, which exhibit a number of innovative qualities for accurate taxonomic identification.

Black plum (Vitex doniana Sweet) is a sub-Saharan African wild species of the family Lamiaceae that significantly contribute to improving local communities’ livelihoods, especially in women. It generated an average income of US$D 80 during the vegetable harvesting season, per individual seller. This species has numerous applications for not only rural dwellers, but also for those in urban areas where it is used for food, healthcare and arts. However, the plant is overexploited by users of this multipurpose species. Among the threatening factors are bushfires and the low natural regeneration due to poor seed germination caused by seed dormancy. This overexploitation will induce the depletion and disappearance of the species in its natural habitat, thus causing an ecological imbalance and genetic erosion. The conservation of this species must therefore be done through its preservation in the natural environment, production, domestication and awareness of the populations. In this work, we review the existing literature on the species, focusing on geographic distribution, utilisation and threats to natural populations, propagation and agronomy, national and international trade, conservation of genetic resources, prospects for domestication and commercial production, and methods for genetic improvement. The findings provide an overview to guide the development of strategies for genetic resource conservation, domestication, commercial production, and genetic improvement to meet the increasing demand for this resource.