LOSS OF MONOTERPENES FROM Tagetes minuta L. FRUITS AT EARLY DECOMPOSITION PROCESS

CLAUDIA M. LAURET; MARÍA P. ZUNINO ; SEBASTIÁN DAMBOLENA; JULIO A. ZYGADLO ; M. LIZA LÓPEZ

San Juan

Congreso; 2da. REunión conjunta de Sociedades de Biología de la República Argentina; 2011

SBC,,Sociedad Argentina de Biología, Sociedad Biología de Tucumán, Universidad Nacional de San Juan, Universidad Católica de Cuyo

Monoterpenes are secondary metabolites with recognized ecophysiological functions as anti-herbivory, allelopathic and modulators of nutrient cycling. No information is available on the pattern of monoterpenes loss at early decomposition process of Tagetes minuta (Asteraceae), a species with presumably important chemo-ecological activity. We conducted a litterbag study during a short period of time (35 days) in order to detect the loss of monoterpenes from the essential oil stored in the fruits by means of GC studies. The overall decrease of essential oil content was 59% in contrast to a low decrease of biomass (11.4%). However, the pattern of biomass loss adjusted to a quadratic function Loss of oxygenated monoterpenes from fruit litter was higher (58.8%) than hydrocarbon monoterpenes (54.3%). Major losses of compounds were registered for b-ocimene (60.1%), (E)-ocimenone (62.6%), (Z)-ocimenone (59%), dihydrotagetone (55.1%) and (Z)-tagetone (57.2%). The pattern of loss for each compound adjusted significantly to linear regressions.