Adaptability trials on Rosa damascena Mill. genotypes in different provinces of Iran

To evaluate Adaptability, flower yield performance and stability of Rosa damascena Mill.) from different regions of Iran, an experiment was conducted by Research Institute of Forests and Rangelands, at 8 locations (Sanandaj, Hamedan, Arak, Isfahan, Dezful, Stahban, Kerman and Mashhad) for 5 years (2004-8), using of randomized complete blocks design with 3 replications. The data obtained from 35 accessions in 2 years (2007-2008) were statistically analyzed. Significant differences (pâ_¤0.01) were observed for accessions, environments and accessionenvironment intractions (with the except of accession-environment interaction of petal weight to flower weight ratio). Grand mean for flower yield, flowering period (FP), flower number per plant(FN/P), single flower weight (FW), flower dry matter percentage(FDMP), petal weight to flower weight ratio (PW/FW) and essence gain (Esq.) was 2263.14kg/ha, 23.14 days, 947.45, 2.323g, 21.70%, 0.754 and 0.029%, respectively. Isfahan9, Yazd2, West Azarbaijan1, Isfahan7 and Isfahan1 accessions with 3120.63, 2941.63, 2894.62, 2769.15 and 2716.92 kg/ha, respectively, produced the highest flower yield. Among the experimental sites, Kerman showed the highest means of flower yield (3635.46 kg/ha) and FN/P (1306.21). For FW and PW/FW means, Dezful with 2.878g and 0.865, for FDMP mean Arak with 32.94% and for Esq. mean, Isfahan with 0.073% were superior locations. In addition the accessions belong to arid and semi arid zones such as Isfahan accessions group (with origin of Kashan as the most famous area from view point of Damask rose production in Iran) showed higher flower yield and number, flowering duration, flower dry matter but lower flower weight and essence gain than those belong to moderate and cold zones. Among studied traits only FN/P and FP showed significant (pâ_¤0.01) and positive correlation with flower yield. Five accessions (Guillan1, Lorestan1, Semnan2, Kerman1 and Qazvin1) showed the least environmental variance (Si 2) and so were stable and also the accessions of Guillan1, Lorestan1, Kerman1, Tehran1 and Balouchestan1 were compatible (to locations) for flower yield. The stable accessions with Si 2 parameter produced very low flower yield, FN/P, FDMP and Esq. and for FP and FW showed moderate level same as accessions average. Considering of the least flower and essence yield of the stable accessions with Si 2 and the extent and ecological variation of studied areas, this statistic isnâ__t a suitable parameter for evaluating of stability of traits in Damask rose and not recommend. The accessions of Ardabil1, Hormozgan1, Yazd2, Khouzestan1 and Isfahan5 showed the least environmental coefficient of variation (CVi) and so were stable and also the accessions of Yazd2, Balouchestan1, Hormozgan1, Tehran1 and Kermanshah1 were compatible for flower yield. The stable accessions with CVi parameter, \{\} produced average or higher than the flower yield total mean, FP and FW same as accessions average but FDMP and Esq. less than that. Although we know that stable genotypes with stability type Î_ parameters (Static stability type) such as Si 2 and CVi usually show low yield and yield components, mentioned results suggest that this subject is relative and thus we can find high yield and stable genotypes so that accession of Yazd2 showed in present research. Considering of the results specially possibility of access to high yield and stable genotypes with CVi, this parameter is recommended as a suitable parameter for stability evaluating of traits in Damask rose. The accessions of Yazd2, Isfahan5, Isfahan8, Isfahan4, Khouzestan1, Ardabil1, Isfahan3 and Balouchestan1 were stable and Yazd2, Isfahan5, Isfahan8, Isfahan4, Khouzestan1, Ardabil1, Isfahan6, Isfahan3, Balouchestan1, Isfahan10 and Yazd1 were adaptable accessions for flower yield based on the Eberhart and Russell method characteristics (bi equal to unity ,Sdi 2 or variance due deviation from regression equal to zero and mean of yield without significant difference with total mean of accessions or higher than that). The stable and compatible accessions in this method produced flower yield about average or higher than that, FW about average or less, FP and FDMP about average, FN/P about average or higher but Esq. less than average. The presence of some high flower yield and stable accessions in this method such as Yazd2 and Isfahan5 suggest that a genotype can demonstrate both Static and Dynamic kind of stability and also high flower yield and stability for yield simultaneously. Thus simultaneous selection for flower yield and stability by means of nonparametric methods in Damask rose is possible. The accessions of Isfahan9, Yazd2, Isfahan8, Isfahan7, Isfahan4, Isfahan5 and Isfahan2 (with the highest flower yield respectively) showed the least Lin and Binns superiority index (Pi) and so were stable. In this method the stable accessions produced flower yield, FP, FN/P, FW, FDMP and Esq. higher than the accessions average. The simultaneous behavior of trait yield- trait stability of most of traits was similar to simultaneous behavior of flower yield and stability. With consideration to mentioned aspects, Lin and Binns superiority index (Pi) is the suitable method for discriminating of high flower yield and stable accessions in Damask rose. With the except of negative correlation of bi and Pi, other stability parameters showed significant positive correlation. In general, Yazd2, Isfahan5, Isfahan8, Isfahan4 and Khouzestan1 accessions showed high flower yield and general stability, while, Isfahan9 and west Azar11 with high flower yield and specific stability were compatible accessions for warm, arid and semi-arid areas, such as Kashan, Arak and Kerman. Also, Isfahan7 and Isfahan1 showed to be appropriate accessions for cultivation in temperate, semi-temperate and cold areas, such as Kurdistan, Khorasan and Fars in Iran.