variation and relationships of shoot yield, morphological and phenological traits in chamomile populations (anthemis triumfettii)

the chamomile species of anthemis triumfettii (l.) all is one of important medicinal plant belong to compositae family and it grows as wild species in zagros and alborz mountains, iran. the aim of this study was to evaluation of morphological and phenological traits and their relationships with essential oil. seeds of seven accessions were sown in jiffy pots and transferred to field using randomize block design with three replications in alborz research station, karaj, iran during 2011-12. data were collected and analyzed for canopy diameter, plant height, flower number, flowering date, maturity date, shoot fresh and dry weight, essential oil percentage and gdd to flowering and maturity dates. results showed significance differences for all traits (p<%1) except of essential oil percent. populations of gorgan1 and gorgan2 had higher values for essential oil yield and shoot yield than other populations. population of loshan flowered earlier than other population due to low values of its growth degree days (gdd). simple correlation analysis showed that shoot dry weight was positively correlated with shoot fresh weight, canopy diameter, flower number, and negatively correlated with flowering and maturity date. essential oil content was positively correlated with flower number and negatively correlated with flowering and maturity date. results of stepwise regression analysis for essential oil% as dependant variables and other traits as independent variables showed negative effects of flowering and maturity date and positive effect of canopy diameter on essential oil content. similarly, for essential oil yield as dependent variables, the shoot dry weight, essential oil%, flowering date and gdd were entered in final regression equation. the results of path analysis showed that maturity date had negative direct effect on oil%. in contrast, both shoot dry weight and essential oil% had positive and direct effect on oil yield.