Effect of Gamma Irradiation on Morphological Biochemical and Cytological Attributes of Salvia hispanica L.

Abstract

The present study focuses on investigating the interaction between radiation and biological systems, specifically examining the detrimental effects of radiation. This approach has proven to be effective in determining the optimal tolerance range of radiation on plants, which can lead to the development of beneficial characteristics and help improve the narrow genetic base. The study was conducted on Salvia hispanica L., a medicinally important plant. Inbred seeds of Salvia hispanica L. were subjected to five different doses of gamma rays (50, 100, 150, 200, 250 Gy) using a Co-60 source with a gamma irradiator of 7.247 k rate. The seeds were sown in triplicate, along with a control set. Various characteristics were assessed, including germination percentage, survival percentage, presence of chlorophyll mutants, and plant height. The results indicate that lower doses of gamma irradiation (<LD50) positively influence plant growth, including plant height, inflorescence size, and productivity. However, higher doses of gamma radiation (>LD50) have detrimental effects on several plant attributes, such as seed germination, survivability, inflorescence size, and pollen fertility. Chromosomal abnormalities were also observed, with an increase in their occurrence corresponding to higher doses of gamma radiation. Germination percentage and survivability were found to decrease as the dose of gamma radiation increased. The dose of 50 Gy resulted in the highest level of genetic variability. Additionally, compared to the control group, a significant percentage of chromosomal abnormalities, particularly stickiness and scattering, was observed at a dose of 250 Gy. Lower doses of gamma radiation (specifically 50 and 100 Gy) showed statistically significant (p>0.5) positive responses in Salvia plants, including plant height, leaf area, leaf mutants, inflorescence axis, and seed size. On the other hand, higher doses of radiation proved to be fatal for the plants.In summary, this study provides valuable insights into the effects of gamma radiation on Salvia hispanica L., highlighting the optimal dose range for inducing beneficial changes in plant characteristics while also emphasizing the harmful consequences associated with higher doses of radiation.