Development of seedless and Mal Secco tolerant mutant lemons through budwood irradiation

• Published in: Scientia horticulturae Vol. 112; no. 2; pp. 184 - 190
• Main Authors: Gulsen, O., Uzun, A., Pala, H., Canihos, E., Kafa, G.
• Format: Journal Article
• Language: English
• Published: Amsterdam Elsevier B.V 26.03.2007; Elsevier
• Subjects: Agronomy. Soil science and plant productions; Biological and medical sciences; buds; Citrus limon; disease incidence; disease resistance; disease severity; dosage; fruit crops; Fundamental and applied biological sciences. Psychology; fungal diseases of plants; Gamma irradiation; genetic resistance; Genetics and breeding of economic plants; irradiation; lemons; lethal dose 50; Mal secco; mutagenesis; mutants; Mutation breeding; Phoma tracheiphila; plant breeding; plant genetic resources; plant morphology; plant pathogenic fungi; seed productivity; seedless varieties; Phoma tracheiphila; Citrus limon; Gamma irradiation; Mal secco; Mutation breeding; Plant pathogen; Horticulture; Citrus fruit; Rutaceae; Tolerance; Medicinal plant; Fungi; Seedless varieties; Dicotyledones; Angiospermae; Genetic improvement; Spermatophyta; Fungi Imperfecti; Mutation; Shoot; Thallophyta
• ISSN: 0304-4238; 1879-1018
• DOI: 10.1016/j.scienta.2006.12.040

Mal secco (caused by Phoma tracheiphila (Petri) Kantsch. and Gik.) is the most destructive fungal disease of lemon plantations worldwide and seedless lemons would be preferred by most consumers. Five dosage levels, 0, 3, 5, 7, and 9 kiloradian (krad), of cobalt ( 60Co) gamma irradiation were applied to budstick of ‘Kutdiken’ lemon ( Citrus limon (L.) Burm. f.) clone KT-2A. Mutations were stabilized in three vegetative generations. Three hundred fifty-eight and 478 M1V3 (mutation one and vegetation three) plants were evaluated for seed number and mal secco tolerance in the field and the greenhouse, respectively. LD 50 was around 5 krad gamma irradiation for ‘Kutdiken’ lemon. The seed number varied from 0 to 34 per fruit. The level of mal secco tolerance also varied significantly among the plants from 1.0 (no symptom) to 4.3 (high level of disease occurance). The stable seedless and mal secco tolerant plants were obtained from 5 and 7 krad irradiation: the three mutants from 5 krad irradiation gave more lemon-like fruits, while 7 krad irradiation caused altered tree morphology and early maturation of fruits. This study shows considerable potential for lemon cultivar improvement aiming to obtain seedless and mal secco tolerant lemons.