EFFECT OF EXPLANTS AND THE GROWTH REGULATORS 2, 4-D AND KINETIN ON CALLUS INDUCTION OF THREE SUNFLOWER GENOTYPES IN VITRO

Abstract

Cotyledon and hypocotyl explants were taken from seedlings of three genotypes (hybrids) of sunflower (Helianthus annuus L.) cultured on two MS media. The first medium contained 2, 4-D( 0.0, 0.5, 1.0, 1.5 or 2.0) mg / l and the second contained 2, 4-D with the same concentrations as above and kinetin (0.0, 0.5 or 1.0 ) mg / l. cultures were divided into two parts. The first part incubated at 25± 1ºC under light condition 1000 Lux for 16 hrs/day and the second incubated in total darkness at the same temperature. After six weeks observations were made on the response of explants for callus induction Results showed that the highest response for callus induction on explants incubated light in supplemented with 2, 4-D(1.5)mg/l produced 49.16% and significantly differed from the control treatment producing 0.0 %. The response of Alhaja genotype to callus induction was higher which produced 47.50% and was significantly higher than Kuds genotype which produced 4.0%.Hypocotyl responded significantly higher than cotyledons in its response which produced 40.67%. The results also showed significant differences among genotypes,2, 4-D concentrations and explants and significant differences among 2, 4-D and kinetin, genotypes and explants in their response to callus induction in light and dark condition.Additionally there was significant effect for kinetin concentrations in this parameter of which the concentration 1.0 mg /l was significantly higher in both light and dark which produced percentage response of 37.33 % and 15.83 % respectively.