Marker assisted selection in plant breeding

Marker assisted selection (MAS) is ‘smart breeding’ or fast track plant breeding technology. It is one tool utilized in breeding companies and research institutes for fast development of improved varieties, giving possibility to select desirable traits more directly using DNA markers. In this review, we discussed the use of MAS in biotic, abiotic, quality and other agronomic traits. Besides, we emphasized the importance of MAS at ICARDA and underlined the successful application of MAS in the last 10 years. The use of molecular markers makes the process of selecting parental lines more efficient based on genetic diversity analysis. It can aid the conventional breeding, especially for certain biotic and abiotic traits laborious to manage. Still, MAS contributed very little to the release of improved cultivars with greater tolerance to abiotic stresses, with only a few exceptions. MAS was extensively used to improve rice varieties, mainly resistant to bacterial blight and blast disease and was applied in drought tolerance along with GPC (Grain protein content) in quality traits. MAS at ICARDA is used to characterize new parental materials for disease resistance genes as well as in screening advanced lines with a focus on association mapping and identification of new QTLs. The application of MAS increased in the last decade. It is more and more used in different crops. However, rice is still the dominant crop in terms of number of publications using MAS. Keywords: marker assisted selection, plant, biotic stress, abiotic stress, quality, ICARD

Amélioration de la production des plantes haploïdes et haploïdes doublés utilisant la culture des anthères du blé

La production des plantes haploïdes et haploïdes doublés, fournit aux sélectionneurs du blé un moyen très efficace pour accélérer la production des lignées homozygotes. La culture des anthères est un parmi les processus d’induction et de régénération des haploïdes et des haploïdes doublés à partir des gamètes mâles. Son haut potentiel de production des plantes haploïdes et son applicabilité chez nombreuses espèces rendent cette technique remarquablement utilisable dans l’amélioration des plantes et l’exploitation commerciales des haploïdes doublés. De ce fait, l’objectif de cette revue est de discuter les publications les plus récentes sur l’amélioration de la culture des anthères de blé et les comparer aux résultats plus ou moins anciens. Ces publications seront d’une grande utilité dans l’amélioration du rendement des plantes haploïdes et haploïdes doublés et ils vont contribuer à faciliter les prochains travaux sur la culture des anthères. Mots clés: Blé, culture des anthères, haploïdes, haploïdes doublés, amélioration génétique.The production of haploids and double haploids, are widely used techniques in advanced breeding programs to speed-up the production of homozygote lines. Anther culture is one of the processes of induction and regeneration of haploids and double haploids from male gametic cells. Due to its high effectiveness and applicability in numerous plant species, it has outstanding potential for plant breeding and commercial exploitation of double haploids. Therefore, the objective of this revue is to discuss recent publications on improvement of wheat anther culture and compare it with older literature. Those publications will be of great utility in yield improvement of haploid and double haploid plants and will contribute for future research on anthers culture. Keywords: Wheat, anther culture, haploids, doubled haploids, genetic improvement

Exploring new biodiversity hotspots in Tuber aestivum natural distribution

Tuber aestivum is associated with a wide range of tree species and is the most widespread edible truffle. Its capability of colonizing many different areas along with a long reaping period, increased in the last decades scientific studies and commercial interest. A number of large- and fine-scale population genetics studies have been conducted to explore its genetic diversity and genetic structure. Recent investigations based on ITS sequence analyses revealed a strong phylogenetic pattern and a higher level of genetic diversity in Turkish and southern European populations than in northern European populations, suggesting that Turkey and southern Europe may have acted as glacial refugia for this species. Despite these findings, the southernmost distributional range of the species is not yet fully explored. With the aim of evaluating other potential diversity hotspots in this study we expand previous investigation, extending the sampling to other southernmost natural T. aestivum areas, such as Moroccan mountainous regions (Middle Atlas), Serbia and several Spanish regions. The ongoing analyses based on haplotypes alignment of the ITS region of the rDNA, reveal as preliminary result a pronounced genetic variability among Moroccan T. aestivum populations, suggesting a possible phylogeographic differentiation also in these new areas of investigation. Additional analyses are underway to better trace natural populations of T. aestivum according to their geographic origin. These aims could be critical both for truffle industry interest in selecting well-adapted inoculum for the production of mycorrhizal seedlings or traceability of truffles provenance, and for the establishment of programs devoted to biodiversity conservation

Understanding photothermal interactions will help expand production range and increase genetic diversity of lentil (Lens culinaris Medik.)

Lentil is a staple in many diets around the world and growing in popularity as a quick-cooking, nutritious, plant-based source of protein in the human diet. Lentil varieties are usually grown close to where they were bred. Future climate change scenarios will result in increased temperatures and shifts in lentil crop production areas, necessitating expanded breeding efforts. We show how we can use a daylength and temperature model to identify varieties most likely to succeed in these new environments, expand genetic diversity, and give plant breeders additional knowledge and tools to help mitigate these changes for lentil producers.This research was conducted as part of the ‘Application of Genomics to Innovation in the Lentil Economy (AGILE)' project funded by Genome Canada and managed by Genome Prairie. We are grateful for the matching financial support from the Saskatchewan Pulse Growers, Western Grains Research Foundation, the Government of Saskatchewan, and the University of Saskatchewan. We acknowledge the support from our international partners: University of Basilicata (UNIBAS) in Italy; Institute for Sustainable Agriculture (IAS) in Spain; Center for Agriculture Research in the Dry Areas (ICARDA) in Morocco, India and Bangladesh; Local Initiatives for Biodiversity, Research and Development (LI-BIRD) in Nepal; and United States Department of Agriculture (USDA CRIS Project 5348-21000-017-00D) in the USA, for conducting field experiments in their respective countries

Selection of Salt-Stress-Tolerant Genotypes during Germination, Growth, and Development in Durum Wheat (Triticum turgidum subsp., durum Desf.)

Salinity is a serious threat to agriculture, causing the inhibition of and alterations in germination and plant growth and development. Durum wheat is highly sensitive to salinity. Therefore, the main objective of this study was to establish a screening method of wheat genotypes, under saline conditions, at the germination and plant growth stages. Our results show a very significant effect of salt stress on the different parameters evaluated in durum wheat, for all treated genotypes. The tolerance screening test during growth and development was more effective than the germination test. The chlorophyll content allowed distinguishing tolerant from sensitive genotypes

Desert Truffles and Truffles in Morocco: Biodiversity of Promising Fungi to Combat Desertification

The desert truffle (Terfezia) and other truffles (Tuber) have a significant economic and ecological value and are considered as important fungi in Morocco. Desert truffles are important to combat desertification and enhance soil fertility. As these fungi form a mycorrhizal symbiosis with several specific desert shrubs, it protects the soil from degradation and assists plant growth in the semi- arid and desert areas. The aim of this short paper is to present the different species of desert truffle that exist in Morocco and identify their macroscopic and microscopic characteristics and their host plants as well as their areas of distribution. There are strong analogies between the species found in Morocco with those previously discovered in other countries. Terfezia arenaria, T. leptoderma and Delastria rosea were mainly available in Mamora forest and T. boudieri in Oualidia. Otherwise, the species Picoa juniperi, Terfezia claveryi, Tirmania pinoyi and T. nivea were present in the Oriental regions of Morocco

Genetic diversity and structure of a barley collection predominatly from North African region

The cultivated barley ranks fourth cereal crop in the world. The demand for higher-yielding, nutritious, and better-adapted crop varieties has increased the need to exploit genebanks diversity. Thus, assessing the genetic diversity of barley is essential to determine the genetic relationship between lines and deploy novel alleles in breeding programs. Here, we used 14 polymorphic Simple Sequence Repeat (SSR) markers to assess genetic diversity, genetic relationship, and population structure of 113 barley lines originated from 14 countries, and the majority from Africa. The average alleles per locus of 5.36, Polymorphism Information Content (PIC) of 0.57, and genetic diversity of 0.61 indicate a high degree of genetic variation in this collection. The Analysis of Molecular Variance AMOVA showed genetic variation within countries to be higher (74%) than among countries (26%). The STRUCTURE analysis was consistent with neighbor-joining clustering and principal components analysis, which identified three main subpopulations clustered primarily according to their geographic origin. Growing environments, migration between and within countries might have caused a considerable genetic diversity observed in the North African barley germplasm. The results of this study contribute to the conservation and utilization of these barley germplasm

Characterization of Desert Truffles in the Great Moroccan Sahara: A Review

Desert truffles are edible mushrooms compulsorily living in symbiosis with plants’ roots. They are rich in essential nutrients and secondary metabolites, conferring therapeutic properties. In Morocco, around ten species can be found in semiarid and arid climate regions with low annual rainfalls and high average temperatures. They can be associated with the Cistus and Pinus species and some other species, but they are detected more often under the Helianthemum species. In this study, we present a short review of the distribution of Moroccan desert truffles in the Great Sahara, along with the progress achieved in their morphological and molecular identification and the evaluation of their nutritional content

Genetic diversity reduction in improved durum wheat cultivars of Morocco as revealed by microsatellite markers

ABSTRACT It has been argued that genetic diversity in crop varieties has been on the decline in recent times due to plant breeding. This can have serious consequences for both the genetic vulnerability of crops and their plasticity when responding to changes in production environments. It is, therefore, vital for plant breeding programs to maintain sufficient diversity in the cultivars deployed for multi-period cultivation. In this study, to understand the temporal genetic diversity in durum wheat, 21 improved durum wheat cultivars released in Morocco, since 1956 and five exotic cultivars currently used in crossing programs were analyzed using 13 microsatellite markers. The analysis revealed a total of 44 alleles and average genetic diversity of 0.485 with genetic distances ranging from 0.077 to 0.846 at 13 microsatellite loci in Moroccan durum wheat cultivars. All the durum cultivars of Morocco could be distinguished using the 13 microsatellite markers. The total number of alleles and unique alleles were highest in cultivars developed before 1990, decreasing in cultivars developed during the 1990s and 2000s, indicating that recent durum breeding efforts have reduced allelic richness in recent cultivars. Thus, deployment of exotic durum wheat lines in breeding programs could enhance genetic diversity in durum wheat cultivars

Seaweed extracts as promising biostimulants for enhancing lead tolerance and accumulation in tomato (Solanum lycopersicum)

Aqueous seaweed extracts are a biological product which have beneficial effects on plant growth as well as improving their resistance to several biotic and abiotic stresses. This work aimed to evaluate the effect of aqueous extracts of three seaweeds Fucus spiralis, Cystoseira ericoides (Phaeophyceae) and Ulva lactuca (Chlorophyceae) harvested from Atlantic coast of Rabat region in Morocco, on lead (Pb) tolerance and accumulation in tomato (Solanum lycopersicum) plants. Aqueous extracts were obtained by the combination of 2 extraction processes, ultrasonication and heating. The brown seaweeds F. spiralis and C. ericoides extracts had good antioxidant activity in the DPPH assay. The growth and physiological parameters were compared between Solanum lycopersicum seedlings grown in hydroponic conditions at 0 and 100 μmol Pb with or without 4% seaweed extract. The F. spiralis and C. ericoides extracts significantly increased the aboveground parts and roots biomass compared to control plants treated with Pb alone. In Pb stress conditions, these seaweed extracts enhanced the plant’s tolerance with a reduction of anthocyanin and proline content. F. spiralis extract treatment led to a significant Pb accumulation in aboveground parts of the plant. The effect of U. lactuca extract on tomato plants biomass, anthocyanin and proline was not significant. The study demonstrated that the aqueous extracts of F. spiralis and C. ericoides improved the plant response to heavy metals stress, highlighting the potential use of these seaweeds in phytoremediation processes