Genetic analysis of earliness in upland cotton using diallel-crossing method

Six upland cotton varieties called Varamin، Mutagenesis، 818-312، Bul-539، B-557 and Chirpan-539 were planted in deputy office of cotton research institute (Varamin) in 2003. Diallel method of crosses including parents without reciprocals was applied to produce F1 populations. Parents and progenies were planted using 3 replications under randomized complete block design (RCBD) in 2004 and 17 phonological properties were evaluated. Results of diallel analysis showed data coincidence with dominant additive model proposed by Hayman and Griffing. Partial dominance effects of genes influenced on controlling Date of first flower، total bloom، plant height، date of first open boll، boll maturation period، earliness، maturity index and product rate index. In contrast، overdominance effects of genes influenced on controlling horizontal flowering interval، vertical flowering interval، boll weight، number of monopodia، yield، bloom index and mean maturity data. Heritability in narrow sense ranged from 0. 58 to 0. 59 for plant height، 0. 66 to 0. 67 for earliness، 0. 53 to. 063 for production rate index، 0. 0 to 0. 19 for yield and was zero for mean maturity data.