Beneficial effects of gamma-irradiation of quinoa seeds on germination and growth

Quinoa is one of the crops well-adapted to high altitude regions that can grow relatively well under drought, humid, and high UV radiation conditions. This study was performed to investigate the effects of gamma-radiation on quinoa. Seeds were treated with various doses of 50 Gy, 100 Gy, 200 Gy, 300 Gy, 400 Gy, 600 Gy, 800 Gy, and 1000 Gy. We investigated germination, as well as plant height, chlorophyll content, and normalized difference vegetation index (NDVI) at 0, 30, 44, 58, and 88 days after transplanting (DAT) and panicle weight at 88 DAT. The plants grown from the seeds treated at radiation doses greater than 200 Gy showed reduced values in most growth and physiological characteristics. The germination rate and germination speed were higher in the 50 Gy-treated seeds than in 0 Gy-treated (control) seeds. Plant height and panicle weight were highest in the plants from 50 Gy-treated seeds. Chlorophyll content was higher in all treated samples than in the controls. NDVI value showed the highest value in 0 Gy controls and plants treated with 50 Gy. The antioxidant activity was also higher in the plants from the seeds treated with 50 Gy and 100 Gy, showing a steady increase as the radiation dose increased even at 200 Gy. The plants from seeds treated with 0 Gy showed higher expression of proteins related to photorespiration and tubulin chains. The plants from seeds treated with 50 Gy induced more stress-responsive proteins.

     

Effect of light and temperature on the germination of lettuce seeds

A short period (15–30 min) at 30° C promotes germination of seeds of Lactuca sativa L. cv. Repolhuda in darkness. Far-red light reverses this stimulation, and the escape curves for phytochrome and high-temperature action are quite similar, indicating that the two factors act at a common point in the chain of events leading to germination. It is suggested that high temperature acts by decreasing the threshold of the active, far-red absorbing, form of phytochrome (Pfr) needed to promote germination.Abbreviations FR far-red light - Pfr far-red-absorbing form of phytochrome - R red light     

Specificity of remote influence of gamma-irradiation of plant seeds on non-irradiated ones

In laboratory and field conditions the consequences of remote influence of gamma-irradiated plant seeds on the non-irradiated ones were studied. It was found the the consequences of the influence depended on the time of storage in conditions ensuring gaseous exchange as well as on radiation susceptibility.     

Effect of temperature on aflatoxin production in Mucuna pruriens seeds

This paper describes the effect of temperature on the level of aflatoxin production in Mucuna pruriens seeds. The highest level of aflatoxin B1 (1.75 micrograms/g) was detected in the samples incubated at 25 degrees C for three weeks. At 20, 30, and 35 degrees C, aflatoxin levels were 0.30 to 0.56, 0.37 to 1.20, and 0.26 to 0.65 micrograms/g, respectively. The lowest concentration of aflatoxin B1 (0.10 to 0.29 microgram/g) was produced at 15 degrees C.     

Yield-forming effect of sandovit on field bean and its influence on the degree of damage to seeds by bruchus rufimanus

The paper presents the yield-forming effect of Sandovit on field bean. The field experiments, carried out in the experimental field of the Regional Experimental Centre in Boguchwala near Rzeszów, showed the significant effect this product has on accelerating the growth of plants and their yield. A significant difference was proved between the experimental object and the control one regarding the number of pods set on a plant and filling them with seeds. The result was an increase in the seed crop by 22.3% in relation to the control object. The effect of Sandovit on decreasing the degree of damage to the field bean seeds was also proved.     

The influence of temperature during seed development on the germination characteristics of millet seeds

Abstract. The cardinal temperatures, rate of germination and final percentage germination of pearl millet seeds were measured for seeds raised in greenhouses maintained at mean air temperatures of 19, 22, 25, 28 and 31°C. The results showed that cardinal temperatures for germination are unaffected by the temperature during seed development and growth. However, the conditions during seed growth did affect seed size and, subsequently, germination rate and seed viability.     

Effect of temperature on aflatoxin production in Mucuna pruriens seeds.

This paper describes the effect of temperature on the level of aflatoxin production in Mucuna pruriens seeds. The highest level of aflatoxin B1 (1.75 micrograms/g) was detected in the samples incubated at 25 degrees C for three weeks. At 20, 30, and 35 degrees C, aflatoxin levels were 0.30 to 0.56, 0.37 to 1.20, and 0.26 to 0.65 micrograms/g, respectively. The lowest concentration of aflatoxin B1 (0.10 to 0.29 microgram/g) was produced at 15 degrees C.     

Effect of gamma-irradiation on the molecular properties of myoglobin

To elucidate the effect of gamma-irradiation on the molecular properties of myoglobin, the secondary and tertiary structures, as well as the molecular weight size of the protein, were examined after irradiation at various irradiation doses. Gamma-irradiation of myoglobin solutions caused the disruption of the ordered structure of the protein molecules, as well as degradation, crosslinking, and aggregation of the polypeptide chains. A SDSPAGE study indicated that irradiation caused initial fragmentation of the proteins and subsequent aggregation, due to cross-linking of the protein molecules. The effect of irradiation on the protein was more significant at lower protein concentrations. Ascorbic acid protected against the degradation and aggregation of proteins by scavenging oxygen radicals that are produced by irradiation. A circular dichroism study showed that an increase of the irradiation decreased the alpha-helical content of myoglobin with a concurrent increase of the aperiodic structure content. Fluorescence spectroscopy indicated that irradiation increased the emission intensity that was excited at 280 nm.     

Effect of gamma-irradiation on dye-DNA binding.

The effect of gamma-rays on the binding of proflavine and acridine orange to DNA was investigated by spectrophotometry. The effect of irradiation was observed on the buffered solutions of the free dye and free DNA. A dose of about 35 krad caused a hyperchromicity of 30-40 per cent to the DNA peak at 258 nm, while the same dose introduced a hypochromic effect to the monomer peaks of the dyes by 30 per cent. This implied that gamma-rays have an effect of decreasing the monomer concentration of free-day molecules in solution. From the results, we conclude that more dye is bound to the changed conformation of dye-bound DNA on irradiation. Scratchard-binding isotherms drawn for the unirradiated and irradiated complexes of Pf-DNA showed interesting differences. Similar isotherms could not be obtained for the acridine orange-DNA system.