Life Cycle and Culturing of Phytomonas serpens (Gibbs), a Trypanosomatid Parasite of Tomatoes

Abstract

Pure cultures of a trypanosomatid isolated from tomato fruits infected laboratory‐raised tomatoes and nymphs of the hemipieran coreid Phthia picta. The flagellate could be transmitted back and forth from tomatoes to insects. Light and electron microscopy studies were done on culture, tomato and insect forms. Examination of enzymes of the ornithine‐arginine metabolism revealed absence of arginase and presence of arginine deiminase and citrulline hydrolase. Monoclonal antibodies specific for Phytomonas spp. reacted positively with tomato and insect forms. Endonuclease digestion of the k‐DNA of various Phytomonas spp. revealed a unique, distinctive pattern for the tomato flagellate. This flagellate thus seems to constitute a separate species of Phytomonas which we now call Phytomonas serpens (Gibbs).

A proton pumping pyrophosphatase in acidocalcisomes of Herpetomonas sp.

“…The parasites live mostly in the xylem and phloem of the infected plants and are transmitted through the bite of phytophagous insects [1][2][3][4]. In the biological cycle of these pathogens, several plant-sucking insects act as intermediate hosts and the plant acts as the main host [5]. These parasites have ultrastructural features typical of the family Trypanosomatidae containing kinetoplast, glycosomes, endoplasmic reticulum and one single tubular mitochondrion [4,6,7].…”

Aspectos biológicos de Phthia picta (Drury, 1770) (Hemiptera: Coreidae) em tomateiro sob condições controladas

“…Não existem estimativas numéricas dos danos causados pelo percevejo-do-tomate, no entanto, em termos qualitativos são significativos, sobretudo quando causados por adultos em frutos de mesa, para os quais a qualidade é fundamental. Diversos pesquisadores relataram que esse percevejo pode ser vetor de protozoários flagelados, mas esses nem sempre causam efeitos patológicos nas plantas (JANKEVICIUS et al, 1989;BRAZIL et al, 1990;FIORINI et al, 1993). No entanto, são necessários mais estudos a esse respeito para elucidar tal questão.…”

Fatty Acid and Sterol Composition of Three Phytomonas Species

“…Insects have been suspected as a vector of plant flagellates. Jankevicius et al (1989) showed in controlled laboratory cage experiments that P. serpens, the tomato parasite, is transmitted by the bite of coreid insect Phthia picta. The presence of trypanosomatids in plants of economic interest has attracted the attention of several research groups.…”