| dc.description.abstract | The experiment was carried out at the Genetic Engineering Laboratory of the Department of Genetics and Plant
Breeding, Sylhet Agricultural University, Sylhet to develop a suitable protocol for high frequency plant
regeneration of tomato (Lycopersicon esculentum). An efficient system for high frequency plant regeneration
system of L. esculentum was developed through investigating various factors such as combination of plant
growth regulators; explant type, age and ethylene biosynthesis inhibitor AgNO3. To observe the suitable medium
for callus initiation and shoot regeneration, cotyledonary and hypocotyl explants of L. esculentum cv. BARI
Tomato 5 were cultured on MS medium supplemented with different concentrations of 6-benzyl amino purine
(BA) and α-naphthalene acetic acid (NAA). The ranges of callus initiation and shoot regeneration frequency of
cotyledonary explants were 52.78% to 94.44% and 22.22% to 61.11%, respectively, whereas hypocotyl explants
showed 61.11% to 97.22% and 19.44% to 58.33% callus initiation and shoot regeneration frequency,
respectively. The highest callus initiation (94.44%) and shoot regeneration (61.11%) frequency were observed
on MS medium supplemented with 3.0 mg/L BA and 0.2 mg/L NAA in case of cotyledonary explants. To
observe the effect of age of explants source material on shoot regeneration 5 to 9 days old cotyledonary explants
were cultured on MS medium supplemented with 3.0 mg/L BA and 0.2 mg/L NAA and 6 days old cotyledonary
explants showed the highest shoot regeneration frequency (61.11%). The shoot regeneration frequency was
markedly enhanced by the addition of AgNO3. MS medium supplemented with 3.0 mg/L BA, 0.2 mg/L NAA
and 2.0 mg/L AgNO3 showed the maximum shoot regeneration frequency (77.78%). To observe the genotypic
variation for shoot regeneration potentiality 6 days old explants of six L. esculentum genotypes namely BARI
Tomato 2, BARI Tomato 5, BARI Tomato 7, BARI Hybrid Tomato 4, BINA Tomato 3 and BINA Tomato 5
were cultured on MS medium supplemented with 3.0 mg/L BA, 0.2 mg/L NAA and 2.0 mg/L AgNO3. Among
the six genotypes BARI Tomato 2 showed the highest shoot regeneration frequency (91.67%) and BINA
Tomato 3 showed the lowest shoot regeneration frequency (44.44%). MS medium supplemented with 0.1 mg/L
NAA showed the highest frequency (100%) of rooting. The regenerated plantlets were transferred in pot soil and
grown to maturity. | en_US |
