[ca] El present estudi es fonamenta en la idea que Ustilago syntherismae pot ser util per controlar les poblacions de Digitaria sanguinalis. Els objectius van ser estudiar la influencia de diferents variables en la infeccio; la mida de les espiguetes (gran / petita), la profunditat d'enterrament (1 cm / 3 cm), la cohort i el patro de germinacio que seguien (radicular / coleoptilar). El procediment seguit va comportar la realitzacio de dos estudis. En el primer, realitzat en plaques de Petri, no es va tenir en compte la profunditat d'enterrament ni la cohort. En el segon, realitzat en testos, la profunditat d'enterrament i la cohort eren variables a tenir en compte i no ho va ser el patro de germinacio. L'estudi es va realitzar en diferents fases; la primera centrada en el metode d'infiltracio al buit de U. syntherismae a D. sanguinalis, seguida d'una fase de sembra de les espiguetes, la fase seguent va ser la tincio i com a darrera fase l'observacio. Els resultats del primer assaig van permetre constatar amb un nivell de significacio del 0,05 que la mida de les llavors influia en la infeccio, essent mes alta en espiguetes petites que en grans. De la mateixa manera, es va rebutjar la influencia del patro de germinacio. En el segon assaig, tot i no haver pogut obtenir dades suficients per veure com influien les diferents variables estudiades en la infeccio, es va poder observar com la profunditat d'enterrament, la infiltracio i la mida de les llavors condicionaven la germinacio de les espiguetes i l'emergencia de les plantules. En aquest cas, tambe amb un nivell de significacio del 0,05, es va poder evidenciar que la profunditat d'enterrament tenia un efecte important tant en la germinacio de les espiguetes com en l'emergencia de les llavors. La variable mida no va mostrar diferencies significatives en el grau d'infeccio de les plantules. D'altra banda, hi va haver indicis que la infiltracio produia un efecte negatiu en la germinacio de les espiguetes i l'emergencia de les plantules.

[en] The present study is based on the idea that Ustilago syntherismae may be useful to control the population of Digitaria sanguinalis. Our aim was to check the influence of several variables in the infection; the size of the spikelets (big /small), the burying depth (1 cm / 3 cm), the cohort and the pattern of germination that they follow (radicular / coleoptilar). The followed process implied carrying two studies. In the first, done in Petri dishes, the burying depth was not considered nor the cohort. In the second, done in pots, burying depth and cohort were variables to be taken into account, but the germination pattern was not. The study was carried out in different phases; the first focused on the vacuum infiltration method from U. syntherismae to D. sanguinalis, followed by the planting phase of the spikelets, the next phase was staining, with observation as the final phase. The results of the first test allowed for the confirmation with a level of relevance of 0.05 that the size of the seeds influenced the infection, being higher in small spikelets rather than in big ones. Similarly, the influence of the germination pattern was rejected. In the second test, in spite of not achieving sufficient data to check how the different variables under study had any influence on the infection, it could be note how the burying depth, the infiltration and the size of the seeds conditioned the germination of the spikelets and the seeding emergence. In this case, also with a level of relevance of 0.05, that the burying depth had an important effect both on the germination and the seeding emergence could be demonstrated. The variable of size did not show any significant differences in the degree of infection of the seeds. On the other hand, there was some evidence that infiltration had a negative effect on the germination of the spikelets and the seeding emergence.