Optimisation de la transformation génétique de la pomme de terre par Agrobacterium tumefaciens. Utilisation de la résistance à l'hygromycine comme marqueur sélectif

Optimization of potato genetic transformation by Agrobacterium tumefaciens using hygromycin resistance as selective marker. The objective of this work is the optimization of a genetic transformation and a regeneration protocol of transgenic plants in Solanum tuberosum cv Désirée using hygromycin resistance as selective marker. The gene Cat2 of Nicotiana plumbaginifolia and the gene SU2 of Gossypium hirsutum, both coding for catalases, have been used. Two antibiotic concentrations (5 and 10 mg . l -1 of culture medium) combined with two preculture periods (5 and 20 days) on non-selective medium were tested. Coculture medium was supplemented with 10 mg . l -1 of acetosyringone to test its effect on potato transformation. The addition of this phenolic compound to the coculture medium affected positively the regeneration aptitude of transgenic SU2 plants. Only the combination of 5 mg . l -1 of hygromycin and 20 days of preculture without antibiotic allowed the obtention of plants transformed with the gene SU2. Screening of the rooted shoots with PCR showed 45% of transgenic plants for both molecular constructions used

Thermal analysis and determination of the heavy metal content of the plant Urtica Dioica L. by atomic absorption spectroscopy

Today, medicinal plants are still the primary reservoir of new drugs. They are considered an essential source of raw material for the discovery of new molecules needed for the development of future remedies.Among these plants, we find Urtica dioica L., which belongs to the Urticaceae family. It is a perennial herbaceous plant commonly known as "nettle" it has been reported to have various pharmacological activities like antibacterial, antioxidant, analgesic, anti-inflammatory, antiviral, and anticancer effects. In the present work, we are interested in one hand, in valuing this plant which was harvested from the region of Meknes, by thermal and gravimetric analysis ATD/ATG to determine the loss of mass as a function of temperature. This phenomenon was confirmed by the calcination technique in a muffle furnace at different temperatures (110°C and 300°C, 600°C). on the other hand, after the calcination of the plants, detection of the heavy metal content by an atomic absorption spectroscopy (AAS) technique was performed. The results obtained showed simultaneously high concentrations of Ca, K, Na, Li, and Cd and low concentrations of Pb, Ni, Cu, and Zn

Effects of crop sequences on soil population dynamics of Monosporascus cannonballus ascopsores and Monosporascus root rot and vine decline incidence

[EN] Crop sequences effect on the soil population dynamics of Monosporascus cannonballus ascospores and the incidence of Monosporascus root rot and vine decline (MRRVD), was investigated in a field in which three different cucurbit crops: melon, watermelon, and watermelon grafted onto Cucurbita rootstock, and tomato, were grown during two consecutive growing seasons. Cultivation of melon or watermelon crops in the first growing season resulted in an increase of soil ascopore densities. But, on the contrary, the soil ascospore densities in the second growing season were lower when grafted watermelon or tomatos were cultivated in the first growing season. In the second growing season, MRRVD incidence for each cucurbit crop was significantly different depending on the previous crop, being in general higher when melon or watermelon were the previous crops, slightly lower when the previous crop was grafted watermelon and the lowest when the previous crop was tomato. Disease incidence corresponded with the percentage of isolation of M. cannonballus from the roots, being always significantly lower when the previous crop was tomato. These results demonstrate the potential of crop rotation as a management strategy to reduce infection and reproduction of M. cannonballus, ascospore densities in soil and disease incidence in cucurbits.Ben Salem, I.; M'hamdi, M.; Armengol Fortí, J.; Boughalleb-Mhamdi, N. (2015). Effects of crop sequences on soil population dynamics of Monosporascus cannonballus ascopsores and Monosporascus root rot and vine decline incidence. International Journal of Current Microbiology and Applied Sciences (Online). 4(9):482-500. http://hdl.handle.net/10251/89413S4825004

The Importance of Viscoplastic Strain Rate in the Formation of Center Cracks during the Start-Up Phase of Direct-Chill Cast Aluminum Extrusion Ingots

A comparison of experimental observations and computer simulations shows that trends in the occurrence and severity of center cracks in direct-chill (DC) cast ingots due to different initial casting speed histories may best be explained by the changes in viscoplastic strain rate close to the center of the base of the ingot. The thermomechanical histories of five ingots were simulated and correlations between stresses, strains, strain rates, and liquid pressure drops due to feeding restrictions were considered

Semi-solid constitutive parameters and failure behavior of a cast AA7050 alloy

Materials innovation institute (www.m2i.nl) research framework, project number M42.5.09340; Norsk Hydro Fond for SINTEF; Modelling assisted INnovation for Aluminum DC Casting process (MINAC

The Edge of Perinatal Viability:Understanding the Dutch Position

Contains fulltext : 231104.pdf (publisher's version ) (Open Access