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The objective of this research was to identify the fungi associated to stored seeds of Leucaena leucocephala cv. Peru, during the germination test. For such purpose a mycological analysis was performed on seeds with 6 and 18 months of storage (400 in each case, in four replications of 100), from the storehouse of La Rioja seed farm –belonging to the Livestock Production Enterprise Martí (Matanzas province, Cuba)–. The fungal agents were identified with the aid of taxonomic keys, and the data related to the number of germinated seeds, seeds with disease symptoms and seeds rotten by fungi were processed through the system of comparison of proportions. Eleven fungal species were diagnosed: Penicillium expansum; Aspergillus flavus,isolates 2, 3 and 4; Aspergillus niger; Fusarium oxysporum; Trichoderma sp.; Pestalotia sp.; Rhizopus stolonifer; Cladosporium sphaerospermum and Aspergillus wentii. Among them the first one stood out, with a maximum of 11,25 % of infection in the rotten 18-month seeds. The main symptoms were: seed discoloration, spots on the cotyledons and necrosis of the radicle. It is concluded that the fungal species found belong to seven of the most representative genera, which come from the field and the storehouse. The fungal agent P. expansum showed the highest infection percentage in the germinated and rotten seeds. Only six of the 11 species of fungi caused the main detected symptoms (P. expansum, A. flavus isolate 2, A. niger, F. oxysporum, Trichoderma sp. and Pestalotia sp. [ABSTRACT FROM AUTHOR]

Ten pure isolations of Aspergillus, obtained from previously-disinfected seeds of Leucaena leucocephala cv. Peru, were evaluated from the cultural and morphological point of view, in order to identify to which species they belonged. The fungi were planted from mycelial discs of 7 mm diameter, of cultures which were 10-15 days old, that were placed at the center of glass Petri dishes of 9 cm diameter and were incubated for10 days at 25 ºC, with alternance of 8 h of light by 6 h of darkness. The experimental design was completely randomized, and for each isolate three dishes were used as replications. The cultural aspects measured were: color of the colony on the obverse and reverse, diameter, texture, linear growth (cm/day), aerial growth and substratum pigmentation; and the morphological aspects: size, shape and color of the structures with taxonomic value for the determination of the Aspergillus species. Isolates No. 2, No. 3, No. 4 and No. 5 were in correspondence with the species Aspergillus flavus Link; No. 19, with Aspergillus wentii Wehmer; and treatments No. 7, No. 20 and No. 21, with Aspergillus niger van Tieghem. It is concluded that three Aspergillus species were associated with the stored leucaena seeds. It is recommended to continue the studies to achieve the identification of isolates No. 6 and No. 22 to the species level. [ABSTRACT FROM AUTHOR]

The combined influence of different drying methods, the storage conditions and the physiological age of seeds from Bauhinia purpurea, on their germinative capacity and quality was determined. The treatments for drying were: A) in the pods; B) artificial; and C) under sunlight. The moisture content (MC), germination and viability of the seeds were determined during the 12 months of storage in the cold-storage room. For the information processing multivariate analyses were used. In A the highest value of the germinative capacity (98,67%) was observed in the first evaluation, as in B (100%), where the differences between months were minimal in the whole study. In C the germinative capacity was 79,33% at 12 months, which represented a quantitative increase of longevity of the seeds with regards to A. The germinative process in A, between 0 and 9 months of storage, was completed 9 days after the test started, while in the other evaluations it occurred after 6 days. Between the seeds of B and C a similar performance was observed, only with the difference that the germinative potential could be expressed after 6 days in B at 0 and 2 months; in C at 0,1,2 and 11 months; while in B germination began after 6 days for 9 and 10 months. It is concluded that the treatments essayed in Ais work can be applied to bauhinia seeds, although the best results were obtained when using silica gel (B). [ABSTRACT FROM AUTHOR]

The combined influence of different drying methods, the storage conditions and the physiological age of seeds from Bauhinia purpurea, on their germinative capacity and quality was determined. The treatments for drying were: A) in the pods; B) artificial; and C) under sunlight. The moisture content (MC), germination and viability of the seeds were determined during the 12 months of storage in the cold-storage room. For the information processing multivariate analyses were used. In A the highest value of the germinative capacity (98,67%) was observed in the first evaluation, as in B (100%), where the differences between months were minimal in the whole study. In C the germinative capacity was 79,33% at 12 months, which represented a quantitative increase of longevity of the seeds with regards to A. The germinative process in A, between 0 and 9 months of storage, was completed 9 days after the test started, while in the other evaluations it occurred after 6 days. Between the seeds of B and C a similar performance was observed, only with the difference that the germinative potential could be expressed after 6 days in B at 0 and 2 months; in C at 0, 1, 2 and 11 months; while in B germination began after 6 days for 9 and 10 months. It is concluded that the treatments essayed in this work can be applied to bauhinia seeds, although the best results were obtained when using silica gel (B). [ABSTRACT FROM AUTHOR]

A trial was carried out with the objective of determining the combined influence of different drying methods, the storage under ambient conditions and the physiological age of the seeds from B. purpurea, on their germination capacity and quality. The treatments for drying were: A) in the pods, B) artificial and C) under sunlight. The percentage of viability and germination, as well as the moisture content (MC), were determined, with a monthly frequency during a year of storage; in addition the temperature and relative humidity (maximum and minimum) were recorded during the evaluated period. In the information processing multivariate analyses (GLM and Factorial) were used. In treatments A and C similarities were observed regarding viability and germination, although the seeds reached physiological death at seven and nine months of permanence in the storehouse, respectively. The drying of the seeds with silica gel showed that the loss of germination capacity followed a cubic polynomial model, with a remarkable trend to linearity, and at the end of the study it was 70%. The differences between the MC of the seeds dried artificially (B) and under sunlight (C) allowed to confirm that longevity in B was two to four times higher than in C. The most influencing factors on the rate of quality loss of B. purpurea seeds stored under ambient conditions were moisture content and age of the seeds. [ABSTRACT FROM AUTHOR]

A trial was carried out with the objective of determining the combined influence of different drying methods, the storage under ambient conditions and the physiological age of the seeds from B. purpurea, on their germination capacity and quality. The treatments for drying were: A) in the pods, B) artificial and C) under sunlight. The percentage of viability and germination, as well as the moisture content (MC), were determined, with a monthly frequency during a year of storage; in addition the temperature and relative humidity (maximum and minimum) were recorded during the evaluated period. In the information processing multivariate analyses (GLM and Factorial) were used. In treatments A and C similarities were observed regarding viability and germination, although the seeds reached physiological death at seven and nine months of permanence in the storehouse, respectively. The drying of the seeds with silica gel showed that the loss of germination capacity followed a cubic polynomial model, with a remarkable trend to linearity, and at the end of the study it was 70%. The differences between the MC of the seeds dried artificially (B) and under sunlight (C) allowed to confirm that longevity in B was two to four times higher than in C. The most influencing factors on the rate of quality loss of B. purpurea seeds stored under ambient conditions were moisture content and age of the seeds.

The quality of seeds from Leucaena leucocephala constitutes the guarantee for the future seeding of the Cuban livestock areas; on it depends, to a certain extent, the use of this important protein feed source for animals and its spreading throughout the country. The objective of this work was to determine the quality of the seeds from L. leucocephala cv. Peru, one of the most cultivated commercial varieties nowadays, through the tests recommended by ISTA. The seeds were from the storehouse of the "La Rioja" farm belonging to the Marti Livestock Firm. A completely randomized design with four replications was used. The purity (97,0 and 94,5%) as well as the moisture content (10,09 and 9,87%) were within the optimum range for the stored seeds of this forage plant (6 and 18 months, respectively) and the germination percentages corresponded to the physiological age of the seeds (71 and 26%). Nine fungal genera {Aspergillus, Penicillium, Rhizopus, Chaetomium, Fusarium, Alternaría, Cladosporium, Trichoderma and Pestalotia) and a bacterial one (Erwinia sp.) were detected. The viability values (93,5 and 67,7% for lot 1 and 2, respectively) are considered acceptable for the seeds from this forage plant when it is stored under ambient conditions; nevertheless, the lower value in the seeds of lot 2 may have been caused by the increase in the percentage of seeds rotten by fungi, which had a direct influence on deterioration. Hence, it is recommended to continue the studies for identifying the fungal species associated to them and determining the ones that are pathogenic of this tree legume widely distributed in the livestock systems of the country. [ABSTRACT FROM AUTHOR]

La calidad de las semillas de Leucaena leucocephala constituye la garantía de las futuras siembras de las áreas ganaderas de Cuba; de ella depende, en cierta medida, la utilización de esta importante fuente de alimentación proteica animal y su propagación por el país. El objetivo de este trabajo consistió en determinar la calidad de las simientes de L. leucocephala cv. Perú, una de las variedades comerciales más cultivadas en la actualidad, a través de las pruebas recomendadas por ISTA. Las semillas procedían del almacén de la finca "La Rioja" de la Empresa Pecuaria Martí. Se utilizó un diseño completamente aleatorizado con cuatro réplicas. Tanto la pureza (97,0 y 94,5%) como el contenido de humedad (10,09 y 9,87%) estuvieron en el rango óptimo para las semillas almacenadas de esta forrajera (6 y 18 meses, respectivamente) y los porcentajes de germinación se correspondieron con la edad fisiológica de las semillas (71 y 26%). Se detectaron nueve géneros fungosos (Aspergillus, Penicillium, Rhizopus, Chaetomium, Fusarium, Alternaría, Cladosporium, Trichoderma y Pestalotia) y uno bacteriano (Erwinia sp.). Los valores de viabilidad (93,5 y 67,7% para el lote 1 y 2, respectivamente) se consideran aceptables para las semillas de esta forrajera cuando es almacenada al ambiente; no obstante, el menor valor en las del lote 2 pudo estar dado por el incremento en el porcentaje de semillas podridas por los hongos, lo cual influyó directamente en el deterioro. De ahí que se recomiende continuar los estudios para identificar las especies fungosas asociadas a ellas y determinar las que resulten patógenas de esta leguminosa arbórea ampliamente distribuida en los sistemas ganaderos del país. [ABSTRACT FROM AUTHOR]