Essais de prolifération et d'enracinement de matériel issu de rajeunissement par bouturage d'oliviers adultes (Olea europaea L.) et de germination in vitro : effets de cytokinine et d'auxines

Proliferation and rooting of juvenile and adult olive explants (Olea europaea L.): effects of cytokinin and auxins. The micropropagation trials conducted concerned juvenile and adult material from the ‘Moroccan Picholine’ olive cultivar. Zeatin, added to the proliferation medium, was tested at 0, 1, 5, 10 et 20 mg/l. Root induction was performed on media contaning IAA, IBA or NAA tested at 0, 0.5, 1, 2 et 4 mg/l. A significant (P<0.001) interaction exists between the explant type and the cytokinine concentration on one hand and the type and concentration of auxin on the other hand. The highest bud sprouting and shoot development were obtained on medium supplemented with 5 mg/l zeatin. For economical reasons, satisfying results can be obtained with only 1 mg/l. Rooting of microcuttings reached 100% when NAA, which proved to be the best auxin for root induction, was used at 1 mg/l. No rooting was observed in the case of adult plant material. Further investigations are being undertaken to improve the reactivity of this recalcitrant type of material

Review of agronomic and genetic diversity of Moroccan rice varieties, and their resistance to blast disease (Pyricularia oryzae)

Received: October 25th, 2022 ; Accepted: January 25th, 2023 ; Published: March 9th, 2023 ; Correspondence: [email protected] study on agronomic and genetic characteristics of rice has given us scope to select varieties with desirable characteristics to mitigate various constraints. Rice (Oryza sativa) is the staple food for half of the world's population. However, its production is hampered by a variety of biological constraints. The Blast disease (Pyricularia oryzae) is an important rice disease, and one of the most effective control methods is to use resistant varieties. Study areas in Morocco include the Gharb plains. For all methods, cultural practises like soil levelling seem to be important, but biological control is not widely adopted due to cost, efficacy, and climatic conditions. The bibliographic synthesis was carried out in this context with the main goals of contributing to a better understanding of rice cultivation in Morocco; to identify and characterise the structure of the rice blast pathogen (Pyricularia oryzae), which will allow us to characterise the effects of rice blast; and to research on the Gharb rice field, which resulted in resistant varieties, which will potentially allow producers to have resistant varieties to overcome the diseases. The introduction and development of new rice varieties with high agronomic and socioeconomic value; the selection of lines with high yield, good grain quality, and precocity that are adapted to Moroccan conditions; as well as the development of new lines from Moroccan rice, are among the specific goals

Effet du milieu de culture sur le microbouturage de l'olivier (Olea europeae L.) cv. Picholine Marocaine

Effect of culture medium on micropropagation of olive (Olea europeae L.) cv. Moroccan Picholine. The effect of the basal media OM (Olive Medium), 1/2 MS (Murashige et Skoog with half strength macronutrients), WPM (Lloyd and McCown), 1/2 Miller (Miller with half strength macronutrients), and K&H (medium with Knop macronutrients and Heller micronutrients), supplemented with 5 mg/l Zeatine, on shoot proliferation of mature Moroccan Picholine'cultivar (30 years old) was investigated. OM and 1/2 MS media were the most effective at the early stages of proliferation. A microcutting percentage of up to 91,6 and 90,9 % were achieved in OM and 1/2 MS media respectively but OM was distinguished later by permitting a better shoot growth with no vitrification symptoms The highest percentages of new shoots per explant were obtained with 1/2 MS and OM media (67 and 65 % respectively). OM was the most effective for shoot height (12,42 mm) followed by 1/2 MS (8,92 mm). The other tested media induced an important callus development and leaf chlorosis, and the reduction of shoot growth was noticeable

Otimização de um protocolo para micropropagação da oliveira Ascolano 315

O objetivo foi induzir a multiplicação em explantes de oliveira. Para tanto, foram utilizados segmentos nodais de aproximadamente 2 cm, sem folhas, oriundos de plântulas da variedade Ascolano 315 mantidas in vitro. Os segmentos foram excisados e inoculados em tubos de ensaio contendo 15 mL do meio de cultura Olive Medium (OM) suplementado com 2 g L-1 de carvão ativado, quatro concentrações de 6-benzilaminopurina (BAP) e quatro concentrações de água de coco verde, solidificado com 5,5 g L-1 de ágar e pH ajustado para 5,8 antes da autoclavagem. O meio de cultura foi autoclavado a 121 ºC e 1 atm durante 20 minutos. O delineamento experimental foi inteiramente casualizado, em esquema fatorial 4 x 4. Durante 70 dias, os explantes foram mantidos em sala de crescimento a 25 ± 1ºC, intensidade luminosa de 32 ì mol m-2 s-1 e fotoperíodo de 16 horas. O meio de cultura OM adicionado de 1,0 mg L-1 de BAP e 100 mL L-1 de água de coco proporcionou maior comprimento e biomassa fresca da parte aérea. Maior número de raízes foi obtido com 0,5 mg L-1 de BAP associado a 25 mL L-1 de água de coco. O aumento da concentração de BAP e da dose de água de coco incrementa a biomassa dos calos formados

Genome Modification Approaches to Improve Performance, Quality, and Stress Tolerance of Important Mediterranean Fruit Species (Olea europaea L., Vitis vinifera L., and Quercus suber L.).

In the last decades the interest on traditional Mediterranean fruits highly increased, not only due to the constant demand of consumers for new crop alternatives, but also due to the identification in such species of molecules with important properties for human health (e.g. resveratrol from grapes and oleuropein from olives). Efforts to improve the production capacity and fruit quality in such fruit species, as well as the resistance to biotic and abiotic stress, was achieved by plant breeders using mainly classical breeding approaches (e.g. selection, hybridization and mutagenesis), nevertheless, breeding support by plant tissue culture techniques, marker assisted selection, as well as by genome modification, was also used. Here we will present the state of the art related with the production of transgenic plants in three Mediterranean fruit species with important impact on the economy, olive, grapevine and cork. The achievements, problems and future perspectives will be discussed.This work was financially supported by national funds through FCT (Foundation for Science and Technology) under the Project UID/AGR/00115/2013, PTDC/BIA-BQM/28539/2017, by the Project OLEAVALOR (ALT20-03-0145-FEDER000014) funded by FEDER funds through the Program Alentejo 2020; Hélia Cardoso and Susana Serrazina were supported by FCT through post-doc fellowship SFRH/BPD/109849/2015 and SFRH/BPD/108653/2015, respectively; Andreia Figueiredo was also supported by the investigator FCT program IF/00819/2015