Distribution of phytomonas on oil palms sudden welt stick
Author
Rairán C., Nubia
Mejía, Henry
Calvache G., Hugo H.
Zambrano R., Jorge E.
Grijalva, Orlando
Como citar
Publicación:
Revista Palmas; Vol. 21 Núm. especial, (2000); 148-156
0121-2923
Revista Palmas; Vol. 21 Núm. especial, (2000); 148-156
0121-2923
Abstract
Sudden Welt is an oil palm disease proper of Latin America. It is lethal and attacks palms in productive age causing the destruction of complete lots of lands within the plantations. It is believed that the causing organism is a flagellated cell of the genus Phytomonas. It has not been possible to prove Koch s postulates, for the vector insect is still unknown. With the objective of knowing the penetration place of the flagellated cell, as well as to direct all the efforts towards the evaluation of the insect fauna associated to such place, this study was developed in two plantations located in Cumaral (Meta) and Puerto Wilches (Santander). The following samples were taken: leaf rachis and leaves 1, 9, 17, 25, and 33; peduncles of the masculine inflorescence and bunches; stem pieces at 1, 3, and 5 meters from the base of the palm (in adult palms) and roots of palms affected by sudden welt. Subsequently the concentration of flagellated cells by ml^-1 in the hematocito-meter was determined. All the analyzed palms were carriers of Phytomonas. The greatest concentration of phytomona in the young palm with initial symptoms was observed in bunches and masculine inflorescence peduncles (16-30 x 10^6 flagellated cells by ml^-1), just like in the adult ones (1.03 - 32 x 10^6 flagellated cells by ml^-1). This were followed by young parts of the palm as spears and leaf one (0.8 , 3.9 x 10^6 flagellated cells by ml^-1), and in the case of the adult palm by the samples taken at higher estipe height (1 - 11 x 10^6 flagellated cells by ml^-1). In palms with advanced symptoms it was not possible to count the Phytomonas because of the high grade of decomposition of the inflorescence. In this cases a descendent tendency was observed, presenting a greater accumulation in the roots of young palms (34 x 10^6 flagellated cells by ml^-1) while in the adult palms with higher concentration it was observed in the estipe at medium and low height (1 - 11 x 10^6 flagellated cells by ml^-1), followed by the roots. At the same time, the correlation between masculine inflorescence and the incidence of the disease in the different lots of land was made. It was found that it is 72.9% more possible to acquire the disease when the number of masculine inflorescence rises. This strengthens the fact that the place of penetration of the phytomona is in the peduncle of the inflorescence and towards that the search of the vector insect will be conducted. La Marchitez Sorpresiva es una enfermedad de la Palma de Aceite propia de América Latina; es letal y ataca palmas en edad productiva causando la destrucción de lotes enteros dentro de las plantaciones. Se cree que el organismo causal es un flagelado del género Phytomonas, ya que no ha sido posible comprobar los postulados de Koch, debido a que aún no se conoce el insecto vector. Con el fin de conocer el sitio de penetración del flagelado y encaminar todos los esfuerzos hacia la evaluación de la entomofauna asociada a dicho lugar, se desarrolló este estudio en dos plantaciones ubicadas en Cumaral (Meta) y Puerto Wilches (Santander). Se tomaron muestras de raquis de flechas y hojas 1, 9, 17, 25 y 33; pedúnculos de las inflorescencias masculinas y racimos; trozos de estipe a 1, 3, y 5 metros de la base de la palma (en palmas adultas) y raíces de palmas afectadas por marchitez sorpresiva. Posteriormente se determinó la concentración de flagelados por ml-1 en el hematocitómetro. Todas las palmas analizadas fueron portadoras de Phytomonas. La mayor concentración de la Phytomona en palmas jóvenes con síntomas iniciales se observó en pedúnculos de inflorescencias y racimos (16-30 x 106 flagelados por ml-1), al igual que en las adultas (1.03-32x106 flagelados por ml-1), seguidas por partes jóvenes de la palma como flechas y hoja uno (0.8-3.9x106 flagelados por ml-1), y en los casos de la palma adulta por las muestras tomadas a mayor altura del estipe (1-11x106 flagelados por ml-1). En palmas con síntomas avanzados no se pudo contar las Phytomonas, debido al alto grado de descomposición de las inflorescencias en estos casos se observó una tendencia descendente, presentándose una mayor acumulación en las raíces de palmas jóvenes (34 x 106 flagelados por ml-1) mientras que en las palmas adultas la mayor concentración se observó en el estipe a mediana y baja altura (1-11x106 flagelados por ml-1), seguidos por las raíces. Paralelamente, se realizó la correlación entre las inflorescencias masculinas y la incidencia de la enfermedad en diferentes lotes, encontrando que hay un 72.9% más de probabilidad de adquirir la enfermedad al aumentar el número de inflorescencias masculinas. Todo esto conduce a reforzar que el sitio de penetración de la Phytomonas se encuentra en el pedúnculo de las inflorescencias y hacia él se conducirá la búsqueda del insecto vector.
Sudden Welt is an oil palm disease proper of Latin America. It is lethal and attacks palms in productive age causing the destruction of complete lots of lands within the plantations. It is believed that the causing organism is a flagellated cell of the genus Phytomonas. It has not been possible to prove Koch s postulates, for the vector insect is still unknown. With the objective of knowing the penetration place of the flagellated cell, as well as to direct all the efforts towards the evaluation of the insect fauna associated to such place, this study was developed in two plantations located in Cumaral (Meta) and Puerto Wilches (Santander). The following samples were taken: leaf rachis and leaves 1, 9, 17, 25, and 33; peduncles of the masculine inflorescence and bunches; stem pieces at 1, 3, and 5 meters from the base of the palm (in adult palms) and roots of palms affected by sudden welt. Subsequently the concentration of flagellated cells by ml^-1 in the hematocito-meter was determined. All the analyzed palms were carriers of Phytomonas. The greatest concentration of phytomona in the young palm with initial symptoms was observed in bunches and masculine inflorescence peduncles (16-30 x 10^6 flagellated cells by ml^-1), just like in the adult ones (1.03 - 32 x 10^6 flagellated cells by ml^-1). This were followed by young parts of the palm as spears and leaf one (0.8 , 3.9 x 10^6 flagellated cells by ml^-1), and in the case of the adult palm by the samples taken at higher estipe height (1 - 11 x 10^6 flagellated cells by ml^-1). In palms with advanced symptoms it was not possible to count the Phytomonas because of the high grade of decomposition of the inflorescence. In this cases a descendent tendency was observed, presenting a greater accumulation in the roots of young palms (34 x 10^6 flagellated cells by ml^-1) while in the adult palms with higher concentration it was observed in the estipe at medium and low height (1 - 11 x 10^6 flagellated cells by ml^-1), followed by the roots. At the same time, the correlation between masculine inflorescence and the incidence of the disease in the different lots of land was made. It was found that it is 72.9% more possible to acquire the disease when the number of masculine inflorescence rises. This strengthens the fact that the place of penetration of the phytomona is in the peduncle of the inflorescence and towards that the search of the vector insect will be conducted.
Palabras clave:
palma de aceite
elaeis guineensis
phytomonas
marchitez sorpresiva
enfermedades de las plantas
insectos vectores
palma de aceite
elaeis guineensis
phytomonas
marchitez sorpresiva
enfermedades de las plantas
insectos vectores