Comportamiento del tizón temprano del tomate (Alternaria solani) en las condiciones del municipio de Holguín, Cuba . Ricardo, N.S., Dirección Provincial. Evaluación de fungicidas para el control de tizón temprano (Alternaria solani) en tomate . Maeso, D. Access the full text: NOT AVAILABLE. Lookup the. Se recogen resultados del estudio de la interacción de “A. solani” con tomate y papa empleando aislados fúngicos de Cuba, EEUU, Turquía, Grecia, Rusia y.
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Induction of tomato resistance to Alternaria solani Sor. BoxGuayaquil, Ecuador. Tomato early blight Alternaria solani Sor. The effect of pretreatment of the susceptible tomato cultivar HC with Glomus clarumArthrospira platensis and acibenzolar-S-methyl ASM was determined under sooani conditions. Seven treatments mycorrhizas, spirulina, ASM, their combinations, and an untreated control were studied to assess the plant enzymatic activity and response to the disease after artificial inoculations of a mixture of A.
The mycorrhizas were inoculated only once at planting by gomate the seeds. The induction of six enzyme systems was determined at 0d, 1d, 7d and 10d after pathogen inoculation.
After d of pathogen inoculation, the necrotic leaf area NLAnumber of spots per leaf SPL and yield were determined. The increase in enzyme activity and protection against the pathogen were minimal in the spirulina and control treatments. The combination mycorrhizas-ASM induced higher enzyme activity than the other treatments, with significant differences for glucanase, phenylalanine ammonia-lyase, peroxidase, and polyphenoloxidase. In general, those treatments including ASM showed better results.
Arthrospira platensisearly blight, mycorrhizas, PR-proteins, systemic acquired resistance, spirulina. Se estudiaron siete tratamientos: Todo el experimento fue asperjado con una mezcla de cepas de A. En general, los tratamientos que incluyeron ASM mostraron mejores resultados.
Early blight disease of tomato Alternaria solani Sor. Its control by fungicides, long-term crop rotations and soil fumigation 1 have tomaate largely assayed. The complexity of the inheritance pattern and strong influence of the environmental conditions in natural epidemics of early blight hamper the commercial availability of resistant cultivars 1,2. Induction of resistance, especially by chemical or biological activators, is another alternative quite often used in crop protection to control the disease.
Among the chemical activators of the systemic acquired resistance are salicylic acid, its analogues 2,6-dichloro-isonicotinic acid and benzo 1,2,3 thiadiazolecarbothioic acid S-methyl ester, and its derivative benzo 1,2,3 thiadiazole with S methyl-benzo 1,2,3 thiadiazolecarbo-thiate. SAR is a long distance signaling mechanism that provides broad spectrum and long-lasting resistance to secondary infections throughout the plant 4. This unique feature makes SAR a highly desirable trait in crop production.
The resistance inductors have no direct antimicrobial effects, so it is assumed that the best results in field application are obtained by combining them with fungicides or antibacterial treatment 5. Activation of resistance against A. The ASM showed itself to be effective in the greenhouse, sufficing a single application of the product to achieve protection in the field; however, ASM does not always provide protection against pathogens 8.
Glomus intraradices was highly efficient in harvest index values and fruit fresh weight, respectively Enzymatic activities showed different responses in tomato seedlings according to VAM strains, being Glomus fasciculatum Thaxt. The cyanobacterium Arthrospira alrernaria Nordstedt Gomont Spirulina is marketed primarily as a nutritional supplement in humans Particularly in Germany, it has been registered in the markets for organic products as a plant restorer, not been required to prove its effectiveness Due to the presence of exopolysaccharides in its cultures, it is expected that there is a positive effect on the defense system of plants.
Achieving natural activation of the defense systems of plants as an alternative control is compatible for both cropping systems, where monoculture and the curative approach predominates, as well as in farms managed with an agroecological approach where the nonuse or reduction of traditional chemicals is imperative. The objective of the research was to measure the protection by chemical and biological resistance activators to the damage of A.
Plants of the tomato cultivar Toomate were solahi. This cultivar is susceptible to early blight and low inducing pathogenesis-related proteins PR proteins against A. Seedlings were sown in a dry heat sterilized mix of ferralitic red soil and peat contained in plastic trays.
They were grown at room temperature in houses protected with anti-aphid mesh and ultraviolet-radiation-absorbent plexiglass roof for 45 days.
Then, the seedlings were transplanted to the field in the morning at a planting distance of 0. Previous soil analysis of the experimental area indicated an average number of viable young VAM spores of Table 1 shows the different resistance-inducing products and treatments.
Plagas y enfermedades del tomate
Doses of the commercial products were adjusted as recommended by the manufacturer, except in the case of Spirulina that was chosen arbitrarily. The experiment time was optimal for growing tomatoes, so that a low natural infection was expected. At 59 d post-transplant, all treatments were inoculated with a mixture of four Rn pathogenic isolates of A.
Subsequently, the mycelium of each isolate was vacuum filtered through filter paper Whatman 1weighed and proportionally fragmented into blender for min. A tomatf suspension of fresh mycelium in sterile distilled water 4.
L -1 was prepared and each plant inoculated with ml of the suspension with a 1-liter one-hand pressure sprayer after It has been found that some inducers perform well when single pathogen isolates are used for inoculation, but not so well when mixtures of two or three pathogen alternarua are used 8. Leaf samples were taken from the plotstreated 59 days after planting, just before inoculation with the fungus.
This time was considered time 0. Subsequently, samples at 1, 7 and 10d post-inoculation for the enzymatic dynamics Table 2. Leaves between the 2nd to 4th positions from the ground were selected as the most susceptible to early blight The methodology 7 consisted of macerating with liquid nitrogen and homogenizing with sodium acetate 0. The homogenate was incubated with stirring in an ice bath for 45 min, filtered through gauze and centrifuged Protein concentration was determined by the Bradford Homate brilliant blue assay is accomplished by measurement of absorbance at nm.
The standard bovine serum albumin curve was calibrated from a stock solution of 1mg. These methods can be described briefly as follows. The product of reaction absorbs at nm.
Principales plagas y enfermedades del tomate
Phenylalanine ammonia lyase PAL: The reaction product, cinnamic acid, absorbs at nm, and the reaction rate was determined with its algernaria. The calibration pattern curve was performed with cinnamic acid at1 mg.
The reaction rate of oxidation was determined by recording the product absorbance at nm. Variation in the optical density was determined for two minutes at 15 sec. The reaction product absorbs at nm.
The specific activity of each enzyme was determined as Specific Act. Foliar damage by A. Leaf damage were determined by two recommended methods for this plant-pathogen interaction After 10 days of inoculating the pathogen, the numbers of spots per leaf SPL were counted in solwni plants per treatment.
At 12 days post-inoculation, the percentage of necrotic area per leaf NLA was determined in all plants by visual assessment by two evaluators see time line in Table 2. The yield of the harvests at 70 and 79d from transplanting was measured. Not marketable fruits were discarded. Experimental design and analysis. A random block design with three replications and seven treatments per block was used. Each alternraia consisted of six rows with about 14 plants in alernaria the two outer rows were discarded to eliminate edge effects.
Variance analysis was performed. The analysis of the nine response variables was integrated using analysis of the principal components with standardized data due to the different scales on a correlation matrix Detectable levels of all enzymes were observed in the control treatment Table 3confirming the existence of a constitutive enzyme level in the cultivar. The control plants showed the lowest enzyme levels in almost all treatments. It should be pointed out that there were a low level of mycorrhizas in the field blocks 22between young viable spores data not shown.
All treatments with acibenzolar-S-methyl induced the alternariw levels of foliar enzyme activity after A. The treatments with spirulina-mycorrhizas, spirulina alone, and the control not treated showed the lowest level of all the enzymes analyzed Fig. On average from all enzymes, covering the seeds with mycorrhizas showed an intermediate position among of all the treatments Fig.
In most treatments, glucanase was notably the enzyme with higher level over 4. On the other hand, none of the treatments showed enzymatic activity over 4. The content of enzymes increased with time 1d to 10d Fig.
It should be noticed that only the treatment with mycorrhizas and spirulina-mycorrhizas stimulated some enzymes between 7d to 10d significantly Fig. The enzyme CHIT showed no significant differences in none of the treatment at 0d, nor elicited at 24h after inoculations of the pathogen data not shownand in general at none of the times evaluated.
Only in ASM-spirulina and spirulina-mycorrhizas treatments, the differences were significant Fig. Ten days after inoculations with A. Comparing the effects of the treatments at 10d, the ASM-mycorrhiza combination induced significantly higher level of enzymes than the worst treatments control and spirulina-mycorrhizas.
Moreover, all treatments that included ASM were statistically superior to the control, excepting ASM-spirulina that did not show significant differences. All inoculated plants were infected, although the level of infection in all treatments was low. The overall average was Leaf necrosis development was yomate by its position on the plant age as expected for A. No significant differences among treatments were observed with ASM-mycorrhizas, although more damage was observed in all the treatments with spirulina Fig.
Figure 2 shows older leaves to be more susceptible to the pathogen infections with more necrotic areas A and generally more number of spots B. Spot size mm predominated in all treatments, irrespective of leaf position Fig. It must be pointed out that altternaria this experiment, inoculum pressure remained low, judged by the surrounding tomato fields, which showed no early blight epidemics or significant damage. The maximum damage in terms of SPL and NLA matched the low-medium degrees of the scales proposed to evaluate the disease in the same province 18where up to 20 spots were included in the lowest leaves The lowest percentage of NLA was achieved in the ne of ASM-mycorrhizas, while the spirulina treatment was the most affected Fig.
The results showed herein suggested the ASM-mycorrhizas treatment to reduce the progression of mm necrotic spots in the host lowest NLA rather than to prevent infection events highest SPL.