The aim of this study was to select the abiotic tolerant sorghum mutants using chlorophyll a transient OJIP analysis of PSⅠ and PSⅡ so called Kautsky’s effect within 1 second. It was clearly identified that wwt-and drought tolerant sorghum mutants could be classified by wet factor index(WFI). On the basis of WFI, wet tolerant sorghum matants were classified as follows; Ⅰ group, MUT534 bmr/new, MUT525 bmr; Ⅱ group, M2P1207 bmr, 25M2-0404 bmr, MUT371 bmr24, unknown bmr22, 10M2-0775 bmr, MUT135 bmr23; Ⅲ group, M2P0411 bmr, MUT641 bmr, M2P1064 bmr36, MUT855 bmr, 25M2-0137 bmr/new, MUT436 bmr, M2P0929 bmr, 25M2-0026 bmr, 10M2-0387 bmr, 25M2-0173 bmr/new; Ⅳ group, 25M2-0698 bmr. In conclusion, for the selection of wet tolerance, four photochemical parameters such as Electron transport flux until PSI acceptors per PSII(RE1o/RC), Performance index for energy conservation from photons absorbed by PSII antenna, until the reduction of PSI acceptors(PI_total ABS), Driving force on absorption basis(DF_total ABS) and Electron transport flux from QA to QB per PSII(ETo/RC) were important photochemical parameters deduced from maximum quantum yield and electron transport efficiency.

Development of transgenic plant with desirable traits to cultivated plant is one of the important procedures in plant molecular breeding. However, applicable assessment of transgenic plant in laboratorial scale is not much except cultivating transgenic plant for a whole life in field condition. Here, we analyzed chlorophyll fluorescence in three transgenic soybean lines with AtMYB44 transcription factor for assessment of photosynthetic activity under abiotic stresses such as drought. Soybean varieties used in this study were ‘Bert’ and ‘Bert’ derived three transgenic soybeans, ‘AtMYB44 CM35101’, ‘AtMYB44 CM2471’, and ‘AtMYB44 CM4481’. Analyzed five different chlorophyll fluorescence variables are maximum PSII quantum yield (QY_max), steady state PSII quantum yield (QY_Lss), steady state non-photochemical quenching (NPQ_Lss), coefficient of photochemical quenching in steady-state (Qp_Lss), and fluorescence declineratio in steady-state (Rfd_Lss). To determine main chlorophyll fluorescence variable affected by abiotic stress, principal component analysis (PCA) was conducted with five chlorophyll fluorescence variables measured from four varieties. QY_Lss and NPQ_Lss were main chlorophyll fluorescence variables to evaluate abiotic stress, particularly in drought stress. In comparison with transgenic soybean lines based on chlorophyll fluorescence variables, ‘AtMYB44 CM2471’ and ‘AtMYB44 CM4481’ are more tolerant to drought than the others. Interestingly, three transgenic soybean lines which have a same AtMYB44 gene with different regions of chromosome revealed the quite different responses of chlorophyll fluorescence to drought treatment.

To investigate the application of biochemical markers' and small-sample methods using whole-wheat flours for screening in early generation in Korean wheat breeding system, 74 Korean wheats, including cultivars, local breeding lines and experimental lines, were analyzed. Seed storage protein and amylose contents of grains were evaluated. Biochemical makers, including granule bound starch synthase (GBSS), high molecular weigh glutenin subunits (HMW-GS) and friabilin were also evaluated by using one-dimensional sodium dodecyl sulfate-polyacryla-mide gel electrophoresis with a single kernel. The small­sample methods, including modified SDS-sedimentation test (MST), micro-alkaline water retention capacity (AWRC) and whole-wheat flour swelling volume (WSV) were also tested in this study. Protein content, MST and AWRC was 11.0 - 15.8~% , 2.7 - 26.2 ml and 71.9 - 109.7~% , respectively. Apparent and total amylose content and WSV was 20.6 - 25.0~% , 26.1 - 32.4~% and 9.0 - 16.9 ml, respectively. There were highly significant correlations between MST and AWRC (r=0.592, P<0.001), but Korean wheats showed no significant difference in protein content, amylose content and small-sample methods. In the biochemical markers, Korean wheats contained all three GBSS encoded by Wx loci, except for Suwon 252. Korean wheats showed the high frequency (58.1~% ) of 1Dx2.2 + 1Dy12 subunits of HMW-GS. Friabilin band was present in 46 lines (62.2~% ) and absent in 28 lines (37.8~% ). Friabilin-absence lines showed the higher MST (14.9 ml) and AWRC (92.1~% ) value than friabilin-presence lines (8.5 ml and 82.4~% , respectively).

Rice (Oryza sativa L.) plants were cultivated to examine changes in antioxidative defence mechanism induced by elevated ozone levels. Catalase activities in tolerant Jinpumbyeo and susceptible Chucheongbyeo under ozone fumigation were reduced at 5 hrs and 3 hrs after ozone fumigation, respectively. With the increased ozone supply, peroxidase activity in Jinpumbyeo was steadily enhanced whereas in Chucheongbyeo it was not changed. Four SOD-isozymes were detected by NBT staining of native-PAGE. Two isozymes of them were obviously induced by ozone supply, particularly in Jinpumbyeo. The continuous ozone fumigation increased remarkably putrescine levels in leaves whereas it did not affect the levels of spermidine and spermine. In this study, it was implied that ozone in cell inhibits strongly diamine oxidase and thus promotes ethylene biosynthesis which will cause the senescence in rice plants.