Pellizzaro G (1), Mulas M (2), Duce P (1)
Abstract: The research was conducted in 1998 in a natural reserve located in North-Western Sardinia, Italy, as an initial evaluation of the possible use of the potential biosynthesis of endogenous ethylene by leaves as a biochemical indicator of stress of spontaneous species of the Mediterranean maquis under natural conditions. Two typical species of the Mediterranean maquis were studied: lentisk (Pistacia lentiscus L.), an evergreen sclerophyll traditionally considered as drought tolerant; Cistus (Cistus monspeliensis L.), characterized by a lower degree of sclerophylly, is considered a summer semi-deciduous and has intermediate characteristics between drought tolerant species and summer deciduous ones, being usually defined as drought avoiders. From March until November 1998, the endogenous ethylene produced by the leaves of both species was measured by gas cromatography. During the trial, plant phenology and environmental conditions were monitored, and soil moisture was measured using the gravimetric method. From May until July 1998, a period characterized by severe drought and soil moisture values always lower than the wilting point, ethylene production increased for both species. The amount of ethylene produced dropped quickly as soon as rainfall occurred. Significant differences in ethylene production were observed between the species. The maximum endogenous ethylene productions were equal to 0.89 and 0.3 umol g-1 h-1 for Cistus and Pistacia respectively.
Citazione: Pellizzaro G , Mulas M , Duce P (1999). Seasonal ethylene evolution by leaves of Cistus monspeliensis L. and Pistacia lentiscus L. as an indicator of stress in the Mediterranean maquis . 2° Congresso Nazionale SISEF, Bologna, 20 – 22 Ott 1999, Contributo no. #c2.6.30