To investigate the influence of the mesophyll cells on stomatal opening in response to white light, the segments of isolated epidermis were transferred on partly exposed mesophyll cells of a leaf and stomatal apertures were measured. Transferring the isolated epidermis on partly exposed mesophyll cells of a leaf caused a marked increase on stomatal apertures while stomata in isolated epidermis incubated in MES buffer hardly opened. Mesophyll infiltration with photosynthetic inhibitors (DCMU, DCCD, NaN3) was performed to elucidate the correlation between stomatal apertures and the degree of photosynthetic activity. It was found that transferring the isolated epidermis on partly exposed mesophyll cells of a leaf caused an increase of stomatal apertures depending on the degree of photosynthetic activities. In NaN3 infiltrated leaf discs, transferring the fresh isolated epidermis on partly exposed mesophyll cells of a leaf showed no significant effect, but a slight increase on stomatal apertures. Isolated epidermis alone did not respond to the light properly, but if it was closely contacted with mesophyll cells, the stomata regained the ability of the light response. Therefore, it could be suggested that stomatal apertures were related with the degree of photosynthetic activity in the mesophyll cells.

This study was to verity that the uptake inhibition and accumulation of nitrogen in different potassium levels. Lettuce was used as model plant in this study and grown in pot of 10cm's in diameter and depth with mixture media of vermiculite and perlite under supply of different culture solution for three weeks. Nitrogen absorption at root was inhibited by increased potassium concentration in nutrient solution, and nitrate accumulation of plant was depended on absorption of nitrogen because nitrate content of 0 K level was 4-5 times higher than that of 2 K level, Concentration of ascorbic acid was decreased by increasing the nitrogen absorption, since ascorbic acid (AsA) content of 2K level was higher than those of OK level in both of old leaf and flesh leaf

Mananbyeo was developed from a three way cross ilyang110/Yeongdeog7//Milyang110 in 1999. It has short growing duration about 71 days from seeding to heading and short culm length of 75 cm. It has almost similar number of panicles per hill , spikelets per

Three rice cultivars, Namweonbyeo (early maturing), Hwaseongbyeo (medium maturing) and Dongjinbyeo (medium-late maturing) were trans-planted with 3 different seedling ages to investigate their growth habits and to improve the cultural method in paddy fields in the southern plain area of the Honam region in 1993. The 10-day old seedlings had more vigorous elongation of plant height and higher tillering ability but lower effective tiller rate, when compared with 35-day or 40-day old seedlings. Leaf area index and top dry weight were lower in 10-day old seedlings up to 40 days after transplanting but thereafter, were not different among seedlings ages. CGR was later in 10-day old seedlings, up to 30 days after transplanting, but in 30 to 40 days after transplanting, it was reversed. RGR was the highest in infant seedlings to 40 days after trans-planting, while in 50 days after transplanting, it was reversed. Panicle number and spikelet number per square meter were the highest in 40-day old seedlings, next highest in 35-day old seedlings and the lowest and in adult seedlings up to 40 days after transplanting, while spikelet number per panicle was vice versa. Milled rice yield did not vary significantly by seedling ages, but among the varieties, it was less in Hwaseongbyeo compared with Naweonbyeo and Dongjnbyeo.

ABA and SA showed different effect on stomatal closing on same condition. The addition of 1 mM salicylic acid to fully opened stomata resulted in a significant reductionn of 22 % in stomatal aperture. However, 1 mM ABA reduced 73 % of stomatal aperture. The light absorption spectra of the salicylic acid solution showed that SA was degraded within 1 hour. Therefore, SA solution was resupplied to the detached epidermis every 30 min. during incubation and it was found that even at 10 μM SA induced stomatal closing significantly. Its effect was also greatly pH dependent. The reduction of stomatal aperture caused by 1 mM SA was most effective at lower pH (pH 7.2, 5 %; pH 6.2, 40 %; pH 5.2, 78 %). Therefore, if SA was properly treated to the epidermal strips in the medium, the effects of SA on stomatal closing were similar with those of ABA.

The effect of growth regulators (NAA, BA and GA_3) and light (blue, red and far-red) on the changes in total protein and thylakoid membrane protein pattern of callus from intergeneric protoplast fusion between Nicotiana tabacum and Solanum nigrum were investigated. When the callus were irradiated with different wavelengths of light, blue and red light accelerated the synthesis of total proteins and thylakoid membrane proteins. Particularly, red light led to an increase in the protein synthesis compared to blue light. When the callus were subjected to various combinations of growth regulators, NAA+GA_3 and NAA-BA treatments induced remarkable increase of total proteins and thylakoid membrane proteins accumulation, particulary in the combination of NAA+GA_3 NAA+GA_3 treatment with irradiation of red light showed highest value in the accumulation of total proteins and thylakoid membrane proteins. We conclude that simultaneous application of red light and NAA+GA_3 treatment may induce synergistic effect in the synthesis of total proteins and thylakoid membrane proteins.