179 research outputs found
Resistance verification in Prunus selections to a mixture of thirteen Meloidogyne isolates and resistance mechanisms of a peach-almond hybrid to M. javanica
Treize isolats de #Meloidogyne originaires d'Espagne comprenant #M. incognita (six), #M. arenaria (six) et #M. javanica (trois) ont Ă©tĂ© utilisĂ©s pour vĂ©rifier le niveau de rĂ©sistance de douze porte-greffe de #Prunus. La majoritĂ© de ces porte-greffe Ă©tait constituĂ©e d'hybrides pĂȘcher-amandier en cours de sĂ©lection. Lors d'un premier essai, les hybrides G X N Nos 3, 7, 14, 16 et Cachirulo, l'amandier D-3-5 et le pĂȘcher Nemared ont montrĂ© diffĂ©rents niveaux de rĂ©sistance Ă un mĂ©lange de douze isolats de #Meloidogyne. Le cv. Garrigues s'est rĂ©vĂ©lĂ© sensible. Un second essai a montrĂ© que les hybrides G X N Nos 2, 9 et le cv. Nemaguard sont hautement rĂ©sistants Ă dix isolats de #Meloidogyne, encore que les amandiers D-3-5 et Moncayo, le pĂȘcher GF-305 et l'hybride GF-677 se soient rĂ©vĂ©lĂ©s sensibles. La pĂ©nĂ©tration des nĂ©matodes, ainsi que des bio-essais concernant le dĂ©veloppement, ont indiquĂ© qu'une rĂ©action d'hypersensibilitĂ© est impliquĂ©e dans le mĂ©canisme de rĂ©sistance de G X N No 9 infestĂ© par #M. javanica. Le nĂ©matode induit une rĂ©action nĂ©crotique dans le parenchyme cortical l'entourant, isolant ainsi le tissu mort par une barriĂšre compacte formĂ©e de plusieurs couches de cellules dont les parois contiennent de la callose. Dans la descendance (F2) d'une population de plants de G X N, 92 % de ces derniers se sont montrĂ©s rĂ©sistants. (RĂ©sumĂ© d'auteur
Comparative analysis of morphological and morphometrical characters in six isolates of Pratylenchus vulnus Allen & Jensen, 1951 (Nemata : Tylenchida)
Six populations de #Pratylenchus vulnus$ Allen & Jensen, 1951 provenant d'Europe et d'AmĂ©rique ont Ă©tĂ© analysĂ©es du point de vue morphologique et morphomĂ©trique. Certaines diffĂ©rences ont Ă©tĂ© observĂ©es pour quelques caractĂšres morphologiques (structure du sac post-vulvaire, forme de la spermathĂšque, largeur des champs latĂ©raux). Par contre, des diffĂ©rences significatives concernant tous les caractĂšres morphomĂ©triques (exceptĂ© le rapport "m") ont Ă©tĂ© constatĂ©es entre les populations. Une analyse de corrĂ©lation canonique montre que les relations entre populations pourraient ĂȘtre fonction de leur origine gĂ©ographique et/ou de leur plante hĂŽte. (RĂ©sumĂ© d'auteur
Growth and nutritional response of Nemared peach rootstock infected with Pratylenchus vulnus and the mycorrhizal fungus Glomus mosseae
Les effets de l'interaction entre #Pratylenchus vulnus et le champignon mycorrhizien #Glomus mosseae sur les porte-greffe de pĂȘcher "Nemared" ont Ă©tĂ© Ă©tudiĂ©s en microparcelles pendant deux saisons de croissance. Le poids frais des pieds, le diamĂštre de la tige, la longueur des pieds et le poids frais des racines sont significativement plus faibles chez les pieds infestĂ©s par le nĂ©matode - qu'ils soient ou non colonisĂ©s par #G. mosseae Ă l'aide de mycorrhizes provoquent une diminution de la population finale du nĂ©matode et du nombre de nĂ©matodes par gramme de racine par rapport aux pieds infestĂ©s par #P. vulnus et non traitĂ©s Ă l'aide du champignon. La colonisation par les mycorrhizes n'est pas affectĂ©e par la prĂ©sence du nĂ©matode. Chez les pieds infestĂ©s par le nĂ©matode, le Cu est le seul Ă©lĂ©ment dĂ©ficitaire dĂ©tectĂ© par analyse foliaire, quoique des taux faibles de fer y aient Ă©tĂ© observĂ©s. Les taux les plus Ă©levĂ©s de Ma, Mg, Mn et Zn ont Ă©tĂ© dĂ©tectĂ©s chez les pieds infestĂ©s par #P. vulnus. Les pieds mycorrhizĂ©s recĂšlent les taux les plus Ă©levĂ©s de Cu et d'Al. #G. mosseae est bĂ©nĂ©fique pour la croissance des pĂȘchers "Nemared" mais ne leur confĂšre aucune protection contre #P. vulnus. (RĂ©sumĂ© d'auteur
Wetting pattern of cow urine patch in an Andisol assessed through bromide concentration distribution: A pilot study
Cow urine is a rich source of mobile nutrients such as nitrate (NO3â) and potassium (K+). The aim of this experiment was to evaluate the wetting pattern distribution through soil profile of cow urine patch in an andisol. Two field experiments across two consecutive years were carried out to compare cow urine patches in relation to initial wetting pattern and volume of soil affected. Bromide (Brâ) has successfully been used as an inert hydrologic tracer to indicate the movement of NO3â and K+ in soilâwater systems. The distribution of Brâ (used as a urine tracer) on the soil surface and down the profile was irregular in all the patches. Cow urine patches covered a surface area of 0.27 and 0.35 m2, respectively, and penetrated to a depth of 70 cm. The rapid downward movement of urine occurred through macropore flow but even so, between 27% and 40% of the applied Br- was detected in the 0â5 cm soil layer. Brâ showed concentrations greater than 1500 mg kgâ1 and up to 3000 mg kgâ1, and as the concentration of Brâ decreases, the frequency and depth of affected layers increases. Despite the differences in moisture and in the distribution of the Brâ concentration in both years, the concentration frequency of 500 to 1500 mg kgâ1 represented around 37% of the affected volume of soil (bulb of urine) in both years. Up to 40% of the bulb represented N equivalent rates between 187 and 975 kg N haâ1. These values can potentially be emitted in gases such as NH3, N2O, and N2. It is suggested that the presence of N in the volume of affected soil could vary due to the moisture content of the soil, and that in andisols of southern Chile under permanent grasslands there are a large number of macropores that would induce preferential flows
Bilateral variation of the venous corona mortis with a presentation previously undescribed
The corona mortis is an anatomic variant that involves anastomosis between obturator vessels, external iliac vessels and/or inferior epigastric vessels. It is clinically and surgically important because its section may lead to fatal consequences when pelvic procedures are performed. We report a case in which, during an anatomical dissection in a female cadaver, a bilateral corona mortis that involved obturator vessels and external iliac vessels was found, presenting differences on each side, an undescribed type of corona mortis was found and a classification modification was proposed
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