IDENTIFICATION AND SCREENING OF TOMPR02 eDNA IN SOME TOMATO GENOTYPES AND THE MORPHO· PHYSIOLOGICAL AND YIELD RESPONSE TO SAL T STRESS

Document Type : Original Article

Authors

1 Molecular Biology Department, Genetic Engineering and Biotechnology Research Institute, Menofiya University, Sadat City.

2 Horticulture Research Crops Institute, (ARC), Egypt.

Abstract

Four tomato genotypes were used in this investigation. They were the tolerant
genotype of Lycopersicon penneflii, the seneitive genotype Lycopersicon escuiemum
and two Egyptian tomato cultivars. Strain Band Floradid. They were exposed to four
salt concentration (0.0, 4000, 8000 and 15000ppm) to identify the response of the
morphological. physiological and yield traits. The biochemical and molecular
analyses were also screened to identify tomPR02 gene. Plant height, plant fresh
weight and root dry matter showed high response to salt, and the L. p < /em>enneflii was
found to be the most tolerant genotype whereas, the wild genotype Lycopersicon
esculentum
seemed to be the most sensitive one. The proline content of the
genotype Floradid showed the highest increment. The wild type showed the least
increments in proline content. For yield response, L. penn/71i; showed the most
tolerable. meanwhile wild type L. esculentum was the most seneitive one. Protein
banding patterns screened after 3 days trealment, indicated the presence of a unique
dark stained band only with genotype Strain B. After 33 days of treatment, a newly
synthesized protein was observed under salt concentrations of 4000 and 8000 ppm.
The cathodal Peroxidase isozyme band Ce at R.F. 0.36 cm was suggested to be a
biochemical marker for salinity tolerance. A unique acid phosphatase isozyme band
A1 was also observed at 4000ppm salt Cone. A full length (-2145pb) tomPR02
(P5CS) cDNA was amplified using RT-PCR from total RNA isolated from leaves of
treated plants. The tomPR02 gene was also screened and amplified from different
tomato genotypes to test their tolerance to salinity which was found to present in
some and absent in others. These results might be of great help to the tomato
breeders in Egypt, which enable them to chose the best and tolerant genotypes to be
involved in their breeding programs.

Keywords