Carbon fixation and partitioning in coffee seedlings infested with Pratylenchus coffeae

• Published in: European journal of plant pathology Vol. 110; no. 8; pp. 861 - 865
• Main Authors: Mazzafera, P, Kubo, R.K, Inomoto, M.M
• Format: Journal Article
• Language: English
• Published: Dordrecht Springer 01.10.2004
• Subjects: Biological and medical sciences; Calvin cycle; carbon dioxide; Coffea arabica; coffee (beverage); Fundamental and applied biological sciences. Psychology; Phytopathology. Animal pests. Plant and forest protection; Pratylenchus coffeae; root lesion nematodes; seedlings; Pratylenchus coffeae; Plant pathology; Coffea arabica; Microbiology; Plant pathogen; sucrose transport; Seedlings; Plant; Fixation; Dicotyledones; Angiospermae; Rubiaceae; Helmintha; Nemathelminthia; Spermatophyta; Invertebrata; Photosynthesis; Nematoda
• ISSN: 0929-1873; 1573-8469
• DOI: 10.1007/s10658-004-4839-4

The objective was to study CO2 fixation and photoassimilate partition in coffee (Coffea arabica) seedlings infested with the lesion nematode Pratylenchus coffeae. Seedlings infested with 0, 1000 and 8000 Pratylenchus coffeae nematodes were exposed to 14CO2 and the incorporation and distribution of radioactivity were followed in the roots, stems and leaves. Fresh mass, pigments, soluble sugars, sucrose and specific radioactivity of sucrose in the plant parts were determined. At the highest level of infestation almost all the parameters were significantly changed showing the carbon fixation in the leaves and partitioning to the roots were decreased. Since lesion nematodes are not sedentary and do not form feeding sites that could be characterised as metabolic sinks, it is suggested that their damage is more readily expressed by the leaves, through a reduction in photosynthesis and phloem transport.