INDUCTION OF CALLUS FORMATION FROM DIFFERENT PARTS OF Citrus grandis (OSBECK) FLOWERS

The objectives of the present work were to study the capability of pomelo's floral tissues to produce callus and to investigate the influence of plant growth regulators on callus induction and development. Various parts of flower namely petal, sepal, style, ovary, pistil and cup base were cultured onto Murashige and Skoog (MS) basal medium supplemented with different levels of 2,4-dichlorophenoxyacetic acid (2,4-D), 6-benzylaminopurine (BAP) and 6-Furfurylaminopurine (kinetin). It was found that different parts of flowers favored different levels of hormone for callus induction. The highest formation of callus were obtained from petal and sepal cultured on MS media supplemented with 1.5 mg/l kinetin. A 50 ± 2.3%explants from style and pistil had initiated callus when cultured on MS media supplemented with 0.05 mg/l and 0.10 mg/l BAP, respectively. On the other hand, sucrose agar (SA) media alone had managed to induce callus formation from almost every part of the flowers with a success rate between 7.69 ± 0.32 to 50 ± 3.18%. The uncut part of flowers initiated high percentage of callus (14.6 ± 0.35%) as shown in the study on petal.