Study of yield and yield components in 11 ecotype of Thymus daenensis Celak

Thymus daenensis Celak. is an aromatic and medicinal species which due to hybridization within species and between species has high morphological diversity. This study was carried out in order to evaluate yield and yield components in 11 ecotypes of Thymus daenensis collected from Isfahan, Markazi and Lorestan. This experiment was performed in a randomized complete blocks design with three replications at Research Center for Agriculture and Natural Resources of Isfahan. Spike weight, spike length, number of flowers per spike, shoot height, leaf area, leaf length, leaf width, the largest and smallest diameter of canopy, 1000-grain weight, fresh and dry yield were measured. Analysis of variance showed that there was considerable variation for all studied characters. Results of mean comparisons showed that the highest dry and fresh yield per plant were 114/6 and 386/6 gr for ecotype of Khorramabad 1, respectively. The lowest yield was recorded for ecotype of Khorramabad 2. Maximum spike weight, spike length, number of flowers per spike, the largest diameter of canopy and leaf length was also recorded for ecotype of Khorramabad1. A positive significant correlation was observed between dry yield per plant and the largest diameter of canopy, leaf length, and fresh yield. Correlation between dry yield per plant and leaf width was strongly negative. Factor analysis introduced three factors that justified 79.71% of total variation among characters. Yield was identified as the first factor including dry yield with positive loading factor and leaf width with negative loading factor. Generally, ecotype of Khorramabad 1 was superior to other ecotypes in terms of yield. Canopy diameter, leaf length and leaf width were also determined as the most effective factors on yield per plant.