Ultrastructural changes of cell organelles inArabidopsis stems after gamma irradation

Abstract

We examined ultrastructural changes of the cell organelles of Arabidopsis stems in response to gamma irradiation.Seedlings treated with 0 to 5 Gy developed normally, while height growth in plants exposed to 50 Gy was significantly inhibited. Based on TEM observations, the chloroplasts were extremely sensitive to such irradiation, in particular, the thylakoids were heavily swollen, some portions of the mitochondria and endoplasmic reticulum were structurally altered, and the plasmalemma had pulled away from the cell wall in places. However, no ultrastructural changes in cell organelles occurred at doses of 0 to 5 Gy.

Study of biological effects and oxidative stress related responses in gamma irradiatedArabidopsis thalianaplants

“…Previous studies have also reported divergent results depending on the sensitivity of the plant species and the radiation dose applied. Wi et al [8] reported no alterations in the height of A. thaliana seedlings 12 days after gamma irradiation up to 5 Gy, while exposure to 50 Gy significantly decreased plant height. Irradiation effects on two generations of P. sativum seedlings were studied by Zaka et al [3] reporting doses above 6 Gy significantly inhibited plant growth and productivity in the first generation while the effects were even more severe in the second generation.…”

“…Pine trees are known to be very radiosensitive and while irradiation with 0.1-1 Gy already caused low injuries, irradiation with more than 60 Gy resulted in a massive mortality and no regeneration of pine trees after the Chernobyl accident [7]. For A. thaliana seedlings on the other hand, Wi et al [8] demonstrated that seedlings developed normally after exposure to 5 Gy, while plant height was significantly reduced following exposure to 50 Gy. In general, a screening value, representing a dose rate affecting 5% of the plant species at a 10% level, presented as a predicted no effect dose rate, of 70 Gy h −1 was derived for plants [9].…”

The Impact of Gamma Radiation on Crude Oil Yield and Chemical Composition of Simmondsia chinensis (Jojoba)-Arizona A42 Seeds

“…The effects of gamma radiation on some properties of many plants and seeds were investigated by researchers (Mahmoud, 2002;Wi et al, 2005;Rahimi and Bahrani, 2011). In our study, the crude oil yield of S. chinensis Arizona-A42 seeds was affected by gamma rays in a significantly positive way.…”

“…Some studies have investigated the effects of gamma radiation on plants, including changes at the morphological, physiological and biochemical levels. These effects include changes in the plant photosynthetic pigments, composition of chemical, cellular structure and crude oil yield (Wi et al, 2005).…”

Improved silymarin content in elicited multiple shoot cultures of Silybum marianum L.

“…Gamma rays belong to ionizing radiation and interact on atoms or molecules to produce free radicals in cells. These radicals can damage or modify important components of plant cells and have been reported to affect differentially the morphology, anatomy, biochemistry and physiology of plants depending on the irradiation level (Kim et al 2004;Wi et al 2005;El Sherif et al 2011). This study builds a foundation for optimization of medium components and conditions as a first step towards further research for commercialization.…”