Genetic fidelity testing of soybean plants under allelopathic stress of eucalyptus ground leaves through RAPD and ISSR markers

Abstract

Background and Objectives: In agroforestry system (e.g., Eucalyptus forestry), plant-plant chemical interactions can have a strong impact on the biodiversity and dynamics of these ecosystems. The objective of the study was to evaluate the genetic stability of crop plants under allelopathic stress of tree litter. PCR based analysis system (RAPD and ISSR) was employed to determine molecular markers associated with allelopathic tolerance in Glycine max. Materials and Methods: Pot experiment was conducted with soybean seeds using mixture of soil and Eucalyptus ground leaves (EUGL) in a percentage of 0 (control), 10, 20, 30, 40, 50, (w/w). Leaves were harvested after 3 weeks for DNA extraction and further PCR assays. Genetic fidelity testing was assessed by calculations of genome template stability index (GTS). Results: Collectively, 18 new DNA markers were detected by both RAPD and ISSR analysis, in EUGL exposed plants. The RAPD and ISSR profiles verified a general tendency of decrease in GTS values with exposure to EUGL in a dose-dependent manner. A drastic decrease in GTS was more pronounced by RAPD markers, compared to ISSR. Low estimated GTS values for EUGL plants reflect their high genetic instability. Conclusion: The RAPD seven markers and ISSR 11markers was proved as reliable molecular markers for allelopathy tolerance in Glycine max and could be used in breeding programs. Moreover, lowest estimated GTS values for EUGL plants reflect their high genetic instability.