Samples of Glechoma hederacea were collected at full flowering in seven localities in Vilnius district (Lithuania) at 2005: A - Salininkai, B -Zolyno, C - Mistunai, D -Antakalnis, E - Nemencine, F - Seskine, G -Zujunai.

More than half of the oils were rich in sesquiterpene hydrocarbons (56.5-67.9%). The most predominant compound was germacrene D (14.1-20.7%). The other main constituents were gamma-elemene (9.0-16.0%), beta-elemene (8.7-12.9%), phytols (2.8-15.6%), (Z)-beta-ocimene (2.2-8.5%), 1,8-cineole (92.2-5.4%), beta-ylangene (2.7-4.1%) and germacrene B (2.2-3.9%). Forty-three identified compounds made up 89.1-96.2%. Four oils (A, D-G) might be attributed to germacrene / elemene chemotype and three samples (A-C) containing marked amounts of phytols beside above compounds were of germacrene/elemene/phytols chemotype.

The 36 'Genovese' and 24 'Foglia di Lattuga' samples preliminarily analysed were grown in Tavazzano (MI), and harvested at flowering, from 5th to 10th August 1998. The breeding program started in 1999, by crossing several selected lines of 'Genovese' with 'Foglia di Lattuga' and 'Compatto'. Selected F1 plants were selfpollinated in 2000. Plants of the F2 (2001), F3 (2002) and F4 (2003) generations were selected on the basis of agronomic and morphologic traits, and self-pollinated. Only the seeds from self pollinated plants with satisfactory essential oil content and composition were used to obtain the next generation. In 2004, some F4 plants were replanted in order to evaluate their stability in relation to environmental variations. All leaf harvests were carried out at flowering.

Genovese' showed higher essential oil and linalool content, with almost total absence of methyl chavicol, very abundant in 'Foglia di Lattuga'.

Samples containing leaves of three different plants identified as P. pseudocaryophyllus were collected bimonthly from January 2009 through November 2009, from the same locality in a restinga in the Ilha Comprida municipality, state of Sao Paulo, Atlantic Rain Forest, southeastern Brazil.

Seven compounds were identified and characterized, revealing a predominance of phenylpropanoids (15.4-70.9%) and variable amounts of monoterpenes (0.5-5.3%). The composition of the oil changed month by month. The best yield of oil was obtained in November, and the major component chavibetol was present in all samples (50.2-70.9%). The chavibetol content showed significant seasonal variation, with the maximum percentages of 69.1% and 70.9% measured in January and November, respectively.