Breeding cumin landraces (Cuminum cyminum L.) for drought tolerance based on physiological and genetical traits

• Published in: Journal of applied research on medicinal and aromatic plants 2018-05, Vol.9, p.78-90
• Main Authors: Kazemi, Hossein, Mortazavian, Seyed Mohammad Mahdi, Ghorbani-Javid, Majid
• Format: Article
• Language: English
• Subjects: Breeding; GC–MS; Genetic advance; Genotypic correlation coefficient; Heritability; Physiological traits
• ISSN: 2214-7861; 2214-7861
• DOI: 10.1016/j.jarmap.2018.03.001

•Top-ranking landraces for high essential oil content were grouped.•γ-Terpinene, β-pinene, m-cymene and cuminic aldehyde are main EO compounds.•One-year selection is efficient for few traits in specific condition.•There is diverse drought tolerance mechanism among landraces.•The landrace Golestan was introduced for further breeding research on RWC. The effect of water stress on the different physiological and biochemical traits, including the essential oil (EO) content, the relative water content (RWC) of leaf, soluble sugars, chlorophyll a and b, and carotenoid besides seed yield, was studied in 49 landraces of cumin (Cuminum cyminum L.). The genetic bases of distinct traits were estimated to get an overview of the genetic variability for cumin breeding programs. Heritability, genetic advance, and genotypic and phenotypic correlation coefficients were determined for all the traits. The combined analysis of variance showed significant differences among all the sources of variation. The seed yield and EO content, as well as other traits, were affected by water stress. The GC–MS analysis of the elite landrace, Golestan (Jat), revealed that the main chemical compositions in both conditions were γ-terpinene, β-pinene, m-cymene and cuminic aldehyde. The landrace Golestan (Gonbad) was introduced as a good candidate for further breeding research on RWC. However, this landrace was clustered in medium-oil-yield group, while Semnan (Ivanakey), Yazd (Bafq) and Southern Khorasan (Ghaen) were grouped in the top-ranking landraces for EO. They were also suggested as suitable candidates for studying the physiological mechanisms and breeding involved in pigment and sugar accumulation. According to the results, we suggest carotenoid content, soluble sugars and RWC as drought-tolerance indices in cumin improvement programs.