Phytic acid, myo-inositol (1, 2, 3, 4, 5, 6)-hexakisphosphate, is a material that plants store phosphorus in seeds. Phytic acid is classified as an antinutrient because of indigestibility. Non-ruminant animals, such as human and swine, excrete unavailable phytic acid. The unavailable phytic acid run off to ground water, river, sea, causing eutrophication as a factor. Accordingly, low-phytic acid crops draw the attention due to both nutritional and environmental reasons. Using more than 900 Glycine accessions including G. max, G. soja and G. gracillis, colormetric method was applied for detecting low-phytic acid mutant. Two hundred fifty accessions were screened by the colormetric method so far, but no mutant was identified. Screening of mutants with the rest 710 accessions is in progress. MIPS1 (D-myo-inositol 3-phosphate synthase) is considered as gene related to phytic acid content in soybean. Also, lpa1 (Zea mays low phytic acid 1) known as controlling phytic acid content in maize was recently reported that homologs of lpa1 were responsible for phytic acid content in soybean and located on linkage groups L and N (Chromosomes 19 and 3). After primers were designed from these three candidate genes for phytic acid content, identification of genes responsible for low phytic acid and investigation of genetic variation among 960 accessions will be performed as further study.

A field experiment was conducted to investigate effects of application time and rate of biofertilizer alone and in combination with chemical NPK fertilizer on growth, yield and quality of rice. The biofertilizer used composted food waste as substrate and added with effective microorganism. The treatments included recommended NPK fertilizer(RF, 11-5.5-4.8kg~;10a-1 ), half recommended NPK fertilizer(HRF, 5.5-2.8-2.4kg~;10a-1 ), half recommended NPK fertilizer plus 250kg~;10a-1 biofertilizer(HRF+Bio 250) and 500kg~;10a-1 biofertilizer(HRF+Bio 500). The biofertilizer treatments were applied at 0, 5 and 10 days before transplanting(DBT). Grain yield of HRF+Bio 250 at 5 DBT(648.4kg~;10a-1 ) was statistically similar to the highest obtained in the RF(654.1kg~;10a-1 ). Tiller numbers at HRF plus biofertilizer treatments were already high during the maximum tillering stage, and were similar with that of the RF and higher than that of the HRF during heading stage. Likewise, ripening ratio at HRF plus biofertilizer treatments was similar with that of the RF and higher than that of the HRF. Furthermore, all the biofertilizer treatments improved protein content but reduced the amylose content and palatability compared to treatments with chemical NPK fertilizer alone. Thus, HRF+Bio 250 at 5 DBT can be used to save 50% chemical NPK fertilizer and at the same time obtain an improved rice grain yield and quality.

The effect of mixed treatments of wood vinegar and sulfonylurea-based herbicides on weed control, yield and yield components, and quality of rice was investigated. Two herbicides were tested namely: imazosulfuron-ethyl+thiobencarb[ethyl-1-(2-chloroimidazo[1,2-α ]pyridin-3-ylsulfonyl)-3-(4,6-dimethoxypyrimidin-2-yl) urea+S-4-chlorobenzyl diethyl(thiocarbamate)], and bensulfuronmethyl+butachlor [methyl α -[(4,6-dimethoxypyrimidin-2-ylcarbamoyl)sulfamoyl]-o-toluate+N-butoxymethyl-2-chloro-2',6'-diethylacetanilide]. The experiment was carried out in a randomized complete block design with 3 replications and 5 treatments. Treatments used were recommended(RH: 100%) and half-recommended(HRH: 50%) application rates of each herbicide. Half-recommended application rates were combined with 1 mL wood vinegar 500mL~;water-1 (500) and 1 mL wood vinegar 1000mL~;water-1 (1000) wood vinegar. Plots for no herbicide treatments were also prepared and used as control. Results showed that wood vinegar significantly increased efficacy of HRH in bensulfuron-methyl+butachlor while high efficacy was already obtained in HRH treatment of imazosulfuron-ethyl+thiobencarb. Wood vinegar did not improve the efficacy of imazosulfuron-ethyl+thiobencarb but improved rice yield. Significantly similar rice yields were obtained in the HRH+1000 WV and RH treatments of both herbicides. There were no significant variations in the yield components among the treatments; however, differences in yield can be attributed to the variations in the spikelet number and ripening ratio. Data on rice quality analysis did not show clear trend on the effects of the treatments on grain appearance and nutritional quality.

The effect of biofertilizer in enhancing nutrient quality and antioxidant property of rice grain was investigated. The experiment was carried out in a randomized complete block design with 3 replications and 7 treatments namely : RF = N-P2O5-K2O(11-5.5-4.8kg~;10a-1); half of the recommended fertilizer rate, HRF=N-P2O5-K2O(5.5-2.75-2.4kg~;10a-1): HRF+Bio 250=HRF combined with 250 kg Biofertilizer 10 a-1 ; HRF+Bio 500=HRF combined with 500 kg Biofertilizer 10 a-1; Bio 250=250 kg Biofertilizer 10 a-1; Bio 500=500 kg Biofertilizer 10 a-1; and NF=No Fertilizer. Results showed that HRF+Bio 500 obtained a significantly higher protein content but a significantly lower amylose content compared with RF and NF treatments. Highest phytic acid content was recorded in NF treatment while the lowest was observed in HRF+500 treatment. The highest values in both electron donating ability and reducing power were obtained in HRF+Bio 500 treatment. All treatments obtained higher reducing power than that of the RF treatment and that NF treatment showed comparable values in both electron donating ability and reducing power with those of the treated plots. Highest antimutagenicity property was also observed in HRF+Bio 500 treatment followed by Bio 500 treatment. This study showed the possibility of using biofertilizer to enhance nutritional quality and antioxidant property of rice.

The effect of biofertilizer (compound of microbial inoculants or groups of micro-organisms) on growth and yield of rice was investigated. The experiment was carried out in a randomized complete block design with 3 replications and 7 treatments namely: RF=N-P2O5-K2O (11-5.5-4.8 kg 10a-1 ); half of the recommended fertilizer rate, HRF=N-P2O5-K2O (5.5-2.75-2.4 kg 10a-1 ); HRF+Bio 250=HRF combined with 250 kg biofertilizer 10a-1 ; HRF+Bio 500=HRF combined with 500 kg biofertilizer 10a-1 ; Bio 250=250 kg biofertilizer 10a-1 ; Bio 500=500 kg biofertilizer 10a-1 ; and NF = No Fertilizer. Results showed that the recorded values of plant height, tiller number and chlorophyll content at 40 to 60 days after transplanting (DAT) in HRF+Bio 500 were significantly higher than those recorded in the RF treatment. Similar observations between these two treatments were only recorded from 60 DAT onwards. Yield components were also superior in HRF+Bio 500 treatment and comparable to that of RF. The highest grain yield obtained in HRF+Bio 500 treatment (785.8 kg 10a-1 ) was statistically similar to that of RF (739.8 kg 10a-1 ) but significantly higher than that of NF (506.7 kg 10a-1 ). Finally, head grain recovery (90.9) was low while chalkiness (0.03) was high at HRF+Bio 500 treatment as compared with RF, which were (96.1) and (0.3), respectively. Results showed that combined treatment of HRF and 500 kg biofertilizer 10a-1 has similar effects on the growth and yield of rice with that of RF.

Fifty-four Korean native and 28 foreign rice varieties harvested in 1998 and 1999 were examined for antioxidative activity that is measured to a chemiluminescence and superoxide radical intensity, by the flow injection chemiluminescence (FI-CL) system and an electron spin resonance (ESR) spectrophotometer, respectively. In the chemiluminescence measurement by FI-CL, radical scavenger activity did not differ significantly among rice varieties between origin types of rice varieties, and between storage periods. GinSun and Hongchoengdo, colored rice exhibited high electron scavenging effect by ESR. Therefore, these results indicate that the pigments of rice varieties may play important antioxidative roles and that it may be possible to breed rice varieties with higher antioxidative potentials.