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Copyright of Revista Ciencia y Tecnología Agropecuaria is the property of Agrosavia and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

The objective of this work was to elaborate biological silage using raw trout (Oncorhynchus mykiss (Walbaum, 1792)) wastes under Puno´s environmental conditions; using koji as a culture of Aspergillus oryzae. First, optimal incubation conditions for A. oryzae (koji) were determined using two local carbohydrate sources: potato and barley as well as rice, under temperatures and times suggested by the experimental statistical design of the surface response method. The response variable was the counting of molds as colony forming units per gram (CFU/g). Next different treatments were postulated with koji inocula under optimal temperatures and times with ground raw trout waste and molasses. pH, acidity, histamine and odor measurements of each treatments were carried out. The results were: temperature and optimum incubation time of A. oryzae at 25 °C and 60 hours in barley, 26 °C and 62 hours in potatoes, 25 °C and 60 hrs in rice. The best treatment was the one with the proportion of raw waste of trout : molasses : koji in rice (10 : 1.5 : 1), pH of 4.5, the score of "5" for odor, and lower values of histamine (83.7 mg/kg) up to 90 days of storage at room temperature. This work offers an alternative for the use of trout wastes in the elaboration of biological silage for swine and sheep feed. It also contributes to the decreasing of organic environmental pollution in Puno, Peru. [ABSTRACT FROM AUTHOR]

Copyright of Avances is the property of Instituto de Informacion Cientifica y Tecnologica and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Choosing new genotypes of rice based on the probability of overcoming the test-check. The objective of this work was to validate a statistical methodology for estimating the reliability or normalized response (RNi) and stability of four elite rice genotypes, compared with the control IDIAP 145-05. We used the database from the rice breeding program IDIAP, from experiments conducted from 2009 to 2011, in 31 environments under dryland conditions. The results of the study allowed us to verify that new genotypes significantly exceeded (P<0.05) in grain yield the control used. The four genotypes IDIAP FL 106-11, 137-11 FL IDIAP, IDIAP FL 155 and FL 156 IDIAP had a reliability average of 0.79, 0.75, 0.75 and 0.74, respectively. The normalized probability IDIAP FL 106-11 represents a differential response greater than zero with respect to IDIAP 145-05, in 8 of 10 cases. It also confirmed the reliability is related to the stability parameters based on regression models (bi and S²di). The AMMI multivariate model, considering the PCA1, identified the genotype IDIAP FL 156, as the most stable. GGE Biplot model, based on the PCA2, found that the genotype IDIAP FL 155, had greater stability. The study illustrates that the reliability or standardized response may be useful for more precise recommendations for the use of new genotypes commercially. [ABSTRACT FROM AUTHOR]

The work was carried out during the years 2004 - 2011 in the international Center of Tsukuba, belonging to the International Agency of Cooperation of Japan and in the Territorial Station of Investigations of Grains "Sur del Jíbaro" in Sancti Spíritus with the objective value the employment of the nitrogenous fertilizer of Slow Liberation Ureaformaldehído on the index of agronomic efficiency in the use of the nitrogen and the increment of the agricultural yield for the production of rice; in the first one you study the speed of liberation of the nitrogen of the Ureaformaldehído and the conventional Urea to three temperatures (10; 17.5 and 25 °C); in the second one studies effect of the fertilizer Ureaformaldehído on the agricultural yield and the index of agronomic efficiency in the use of the nitrogen, in the cultivation of the flooded rice. The main results showed the Ureaformaldehído reacted in a significant way in the measure the temperature was incremented, ending up being mineralized a percentage from 82 to the 100 days; on the other hand, the best yield was reached statistically, with the dose of 120 kg of N/ha, for the fertilizer Ureaformaldehído. [ABSTRACT FROM AUTHOR]

The current development of researchers in the field of genetic improvement in Cuba and the necessity of economizing experimental area and resources outlines the necessity to value experimental designs that facilitate an appropriate efficiency with a maximum of economy. This work intends to combine the kindness of DAM, with the adjustment method for line-column to control the soil heterogeneity, and the statistical multivariate techniques, offering the investigator a mathematical tool in the selection of test lines in rice breeding programs. DAM was structured by means of a Latin Square (4x4), with four controls lines (INCA LP-5, INCA LP-2, J-104 and Reforma) and 120 test lines distributed at random in the corresponding subplot. The use of DAM that allows to compare a considerable number of test lines, overcoming the limitations of a not replied experiment, what presupposes an economic benefit for the area reduction, the economy of experimental material and control of the environmental heterogeneity, in combination with statistical multivariate techniques provides a methodology more efficient in the selection of promissory lines in rice breeding program. [ABSTRACT FROM AUTHOR]

In the months of March until July (rainy season) of the year 2003, in areas of the «Blas Roca» farm belonging to «Los Palacios» Rice agroindustrial enterprise, on a «Gley Nodular Concretionary soil, the behavior of six lines (3981, 8748, 8738, 4482, 8554, 8741) and three varieties (INCA LP-7, IACUBA-25 and the commercial variety J-104 as comparison control of rice, seven of them obtained in the breeding program for tolerance to salinity, was studied. The quantitative characters (final plant height, full grains per panicle, panicle per square meter, 1000 grain weight, empty grains per panicle, cycle in days and the agricultural and industrial yields), as well as the qualitative characters (resistance to lodging, shattering, blast and discoloured grain diseases and to the mite Steneotarsonemus spinki Smiley) were evaluated. Some differences among studied genotypes were observed. The highest agricultural and industrial yield and the best behavior to the main plagues and illnesses were obtained for the lines 3981, 8748 and 8554, and the variety INCA LP-7. [ABSTRACT FROM AUTHOR]

Copyright of Revista Colombiana de Biotecnología is the property of Universidad Nacional de Colombia and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

For the introduction of new varieties into the production system, it is recommendable to characterize their behavior in the presence of the common key pests of this crop; therefore the objective of this experiment was to know the response of eight IDIAP varieties and the cultivar Vioal to the presence of populations of the mite Steneotarsonemus spinki. Mite populations were counted every eight days from the 27th day after germination. Five stems per treatment were randomly selected for each of three replications. The weights of whole, vain and chalky grains and the yields were determined. The response to diseases and the agronomic characteristics were evaluated. S. spinki density was compared by simple variance analysis, the influence of the climatic factors was evidenced by main component analysis; a cluster analysis permitted the grouping of varieties according to their full grain weights, and the polynomial regressions evidenced the population tendencies. All the varieties were resistant or moderately resistant to common diseases of the crop. The minima relative humidity changed by the action of rainfall and influenced in the mite dynamic markedly. The highest yields were spowntobe by the varieties with the highest weights of whole grains. The varietal response may be in function of the occurrence of high populations of the mite in stages near flowering, which may directly influence on the decrease or increase of whole grain weights and agricultural yields. [ABSTRACT FROM AUTHOR]

The application of bacterial inoculants in crops economicaly important crops has been an ecological alternative to improve crop yield and to preserve the environment. The obtaining and characterization of native strains associated with several crops and potentially efficient to promote plant growth and to biocontrol the phytopathogens are key steps to the development of microbial inoculants. This research was carried out to characterize strains of Pseudomonas putida, isolated from rice (Oryza sativa L. var. J-104) as phytostimulators and antagonistic agents against Pyricularia grisea. In vitro experiments were carried out to detect the production of indolic compounds and siderophores, antagonistic activity against P. grisea and to assess the phytostimulating effect of the strains in 12-day-old rice plants grown in Murashige and Skoog medium. The results showed the ability of the strains to produce indolacetic acid-like metabolites (45,8 to 56 µg⋅mL-1) and siderophores (7,3 to 39,4µM). The strains showed antagonistic effect against P. grisea (82-86% of fungal growth inhibition) and were also capable of promoting plant growth (by increase in plant height, root length, root fresh weight and aerial part fresh weight), standing out the strains AJ9, AJ14, AJ20 and AJ18 for the best performance. From the practical point of view, these results show the potential of these strains to be used as inoculants in rice crop. [ABSTRACT FROM AUTHOR]

Rice varietal improvement process (Oryza sativa Lin.) implies genotype selection with appropriate resistance levels to Pyricularia grisea Sacc. causing the well-known disease Blast, which is the most important disease for the crop worldwide. Genotypes are sowed in "Infection Beds", where there are favorable conditions and a high incidence of the disease. A high barren seed percentage, which has not been studied yet, has been detected. The barren seed percentage in genotypes of short and middle cycle, and its relationship with the climatic variables: relative humidity, maximal, minimal and middle temperatures, precipitations and the incidence of biotic agents such as P. grisea, Rhizoctonia solani Khun, Sarocladium oryzae Sawada and the insect pest Diatraea saccharalis F. were studied. The results showed that barren seeds were high even in short cycle genotypes or for those of middle cycle, being the most frequent barren seed percentages from 35 to 45 %, In short cycle genotypes, the factor that most contributed to variability in barren seed was P. grisea (48,8%) while stem borer (68.8%) was that in the middle cycle genotypes. The flowering phase was present from April to May. The transition from one month to another was marked by an increment of the minimal temperature, highly correlated with the middle temperature, barren seed percentage, incidence of P. grisea, R. solani and D. saccharalis. These last three factors are correlated among them. [ABSTRACT FROM AUTHOR]

Specificity of four Exserohilum isolates derived from Sorghum halepense (L.) Pers was determined after being inoculated eight plant species (S. halepense, Zea mays, Oryza sativa, Triticum vulgari, Saccharum officinarum, Panicum maximum, Lycopersicum esculentum and Glicine max) under laboratory conditions. Leaf damage was evaluated each 24 hours, up to seven days post inoculation using a scale grade from 0-8. The only affected were S. halepense in all the fungi species tested and in corn only the isolates AS25 and AS28 causing some 1 grade symptom. The most aggressive isolate was AS25, where at 48 hours, it already showed well defined symptoms and at the end of the evaluation, it affected an area of more than 50% with pathogen signals. Isolates recommended are AS26 and AS29 as the best perspectives to develop a biocontroler agent of S. halepense. [ABSTRACT FROM AUTHOR]

The effect of Q-63 chitosan active ingredient (100, 500 and 1000 mg/L) on the germination of Fusarium sp conidia, as well as its potentiality for protecting rice seeds inoculated with the pathogen was studied. The germination percentage of conidia treated with different concentrations of Q-63 was evaluated after 2, 5, 8, 11 and 14 hours, while the fungal infection percentage in seeds treated with Q-63 was determined after 6, 7, 8 and 9 days. The results showed that both 500 and 1000 mg/L concentrations inhibited conidia germination completely until 14 hours. However, the best protective effect on seeds (93.3 %) was obtained with the higher concentration at 9 days. [ABSTRACT FROM AUTHOR]

The in vitro effect of different chitosan concentrations Q-63, (100, 500 and 1000 mg/L) on Sarocladium oryzae mycelial growth and sporulation was studied. Colony diameter was measured after 2, 5, 8, 11 and 13 days. The inhibition percentage of fungal mycelial growth regarding the non-treated control was determined. Results showed the inhibitory effect of chitosan not only on the fungus growth, but also on its sporulation. This effect increased with the highest concentration of chitosan. [ABSTRACT FROM AUTHOR]

El artículo presenta el resumen de la tesis de grado para Máster en Sanidad Vegetal, la cual trata sobre el Tizón de la Vaina, causada por Rhizoctonia solani Kuhn, considerada una enfermedad del cultivo de arroz, de importancia en Cuba y en el mundo.