DATE PALM AND FUSARIOSIS: PROTEINS SYNTHESIS AND INFECTIOUS PROCESS

D. Touam , F. Rahmania
The physiological aspects of the parasitic relation between the date palm and f. sp. albedinis are not known enough. To contribute to a better knowledge of this parasitism, we realized the kinetic study of soluble proteins content, of ribulose-1.5-bisphosphate carboxylase oxygenase (RubisCO), phosphoenolpyruvate carboxylase (PEPC), glutamate oxaloacetate transaminase (GOT) and glutamate deshydrogenase (GDH) activities. For that purpose, vitroplants of date palm belonging to the sensitive cultivar ‘Deglet-Nour’, are infected by watering with a 106 conidia ml-1 inoculum. Quantitative study is realized spectrophotometrically. The results show an increase in protein content and RubisCO and PEPC activities and this, from 48 hours after the addition of the inoculum. From the eighth day, the levels and activities begin to decline gradually until the onset of disease symptoms. Tecsi et al. (1996) showed, in tobacco, a significant decrease in RubisCO amount, from the second day after inoculation by the mosaic virus, while an increase in small but significant activity of PEPC was observed. In wheat plants, degradation of the large subunit of RubisCO enzyme had been detected by Feller et al. (2008), as a result of nitrogen deficiency. Increase in protein content, during the first week, may be due in part to PR proteins accumulation. These responses are induced by the fungal invasion or by an elicitor as a defense mechanism (Dixon and Lamb, 1990). GOT and GDH activities, begin to decline from the first two days after inoculation. These results show a significant exacerbation of primary metabolism, which reflects defense development which, unfortunately, remains insufficient or ineffective in the susceptible cultivar that fails to overcome the attack of the pathogen.
Touam , D. and Rahmania , F. 2013. DATE PALM AND FUSARIOSIS: PROTEINS SYNTHESIS AND INFECTIOUS PROCESS. Acta Hort. (ISHS) 994:365-372
http://www.actahort.org/books/994/994_37.htm
Fusarium oxysporum f. sp. albedinis, RubisCO, PEPC, glutamate oxaloacetate transaminase (GOT), glutamate deshydrogénase (GDH)
French

Acta Horticulturae