Research Article Effects of Growth Regulators on Photosynthetic Pigments and Some Biochemical Attributes in
Shoot Cultures of in vitro Developed Virus Free Sugarcane Genotypes
Shahid Nazir,
Iqbal Hussain,
Rubaika Khurshid,
Muhammad Aslam Javed,
Muhammad Zaffar Iqbal and
Saleem Akhtar
Abstract: Current study evaluates the impact of various plant growth regulators on sugarcane shoot
proliferation, photosynthetic pigments and production of primary metabolites. Two sugarcane genotypes
were in vitro maintained on MS medium having various amounts of 2,4-D for callogenesis, BAP and
kinetin for shoot development and NAA for rooting. Among cytokinins, BAP was the most competent
for shoot induction with maximum fresh weight and shoot length observed at 1.5 mgL–1 in S2007-
AUS285 sugarcane genotype. Lower amounts of 2,4-D produced more callus in S2006-SP93 and higher
fresh weight in S2007-AUS285. Genotype S2006-SP93 was highly susceptible to sugarcane mosaic virus
and this disease incidence was reduced during in vitro propagation work. Disease free plants were
exposed to different levels of hormones with various combinations to investigate the accumulation of
primary metabolites/biochemicals and photosynthetic performance. Significantly higher photosynthetic
pigments were recorded when BAP was used at 1.0 and 1.5 mgL–1 and kinetin was used at 1.0 and 0.5 mgL–1. Moreover, some potential biochemical attributes like free proline, total soluble proteins and total
free amino acids, were also tested in both sugarcane genotypes. S2006-SP93 showed increased levels at
1.0 mgL–1 of BAP and kinetin, while S2007-AUS285 depicted enhanced levels of biochemical at 0.5 and
1.0 mgL–1 of BAP. The study dissected out physiological impacts of plant growth regulators on
photosynthetic pigments and other biochemical attributes of sugarcane genotypes under in vitro conditions.
