Jae-Seong Choi

Quality Characteristics and Antioxidant Activity of Yogurt Added with Whole Barley Floura

Department of Environmental & Chemical Engineering, Seonam UniversityAbstract In this study, a yogurt containing skim milk powder and whole barley flour was fermented with lactic acidbacteria, and its quality and properties were estimated. The yogurts with 1% and 3% barley flour had lower pH values,higher titratable acidity, and higher Brix values than the control. In addition, the viable cell counts were lower andviscosity was higher. The value of L was low, and the values of a and b were high. The yogurt with 3% barley flourhad more lactic acid than the control and showed a substantial increase in the amount of acetic acid. β-Glucan contentand antioxidant activity increased with the amount of barley flour added. In sensory evaluation, there was a similarpreference for the yogurt with 3% barley flour and the control, and as the barley flour content increased, the preferencedecreased. Moreover, the preference for the yogurt was higher among old people.Keywords: yogurt, whole barley flour, β-glucan, sensory evaluation

Effects of Different Seeding Rates on Disease Incidences of Wheat Sharp Eyespot and Selection of Fungicides

This study was conducted to examine the effects of the seeding rate on the disease incidence of sharp eyespot(Rhizoctonia cerealis) on three different varieties and to select effective chemicals to control the disease. When the seeds were sown twice as many as the recommendation, the disease incidence increased by approximately 13%. However, the susceptible variety `Jopummil` alone showed the significantly enhanced disease incidence at a two-fold seeding rate. Two chemicals such as Hexaconazole EC and Tebuconazole EC highly inhibited the fungal growth on agar medium. However, two strobilurin fungicides such as Pyraclostrobin EC and Trifloxystrobin SC were relatively weak. The fungicides tested displayed the similar in vivo antifungal activities as in vitro activities. Hexaconazole EC and Tebuconazole EC showed the strongest both protective and curative activities and the protective activities of the chemicals were generally higher than the curative activities. Hexaconazole EC and Tebuconazole EC controlled the disease by 64% and 73%, respectively, and the two chemicals reduced the disease by 45% and 39%, respectively, when they were applied one day after pathogen inoculation. These results indicate that both Hexaconazole EC and Tebuconazole EC could be used to control sharp eyespot on wheat.

Fungal Distribution and Varieties Resistance to Kernel Discoloration in Korean Two-rowed Barley

Department of Applied Biology, Dong-A University, Busan 604-714, Korea(Received on April 15, 2013; Revised on August 12, 2013; Accepted on August 13, 2013)Barley kernel discoloration (KD) leads to substantial loss in value through downgrading and discounting ofmalting barley. The objective of this research is to investigate fungal distribution and varieties resistance toKD in Korean two-rowed barley. Several fungal organisms including Alternaria spp., Fusarium spp.,Aspergillus spp., Epicoccum spp. and Rhizopus spp. were isolated from Korean two-rowed barley representingKD. The symptoms of KD were brown and black discolorations of the lemma and palea. The most frequentlydetected fungal species was Alternaria spp. which exhibited 69.1% and 72.2% in 2011 and 2012, respectively.Epicoccum spp., Fusarium spp., and Aspergillus spp. were also detected. Fusarium spp., primary pathogen ofbarley head blight, were rarely occurred in the 2011 and their occurrence increased to 4.7% in 2012. Twentycultivars of Korean two-rowed barely were evaluated to KD. The average percentage of KD was 8.0 −36.0% in2011 and 5.2−36.6% in 2012. Two cultivars (‘Sacheon 6’ and ‘Dajinbori’) showed KD of 6.2% to 8.8% anddetermined resistant, however ‘Samdobori’ and ‘Daeyeongbori’ demonstrating KD of 22.2−36.6% werehighly susceptible. ‘Jinyangbori’, ‘Danwonbori’, ‘Sinhobori’ and ‘Kwangmaegbori’ showing KD of less than15% were moderately resistant cultivar. Keywords : Barley, Fungi, Kernel discoloration, Resistance

Optimal Drainage Time of Barley Seeding Synchronized with Rice Harvesting in Paddy Field

We have carried out the experiment to investigate optimal drainage time of barley seeding synchronized with rice harvesting in paddy field. Number of emerged barley seedling on moist paddy field was less than that of common paddy field. It is very hard to plow using combine owing to long time to work on wet condition compared to drying condition of paddy field. According to the drainage time, growth and yield of barley were not significantly different. However, late drainage time decreased the spikes per m 2 . Rice yield and 1,000 usked rice grain weight were not significant depending on drainage times at 15 days, 20 days and 25 days before barley seeding. The range of 1,000 husked rice grain weight was 21.7～22.2 g on different drainage conditions. In results, on considering of soil hardness and time of labor, the optimal contents of soil moisture was about 33%. This study reveals that drainage time at 20 days before barley seeding is proper to increase seedlings and yield.

Fungicide Effects in Vitro and in Field Trials on Fusarium Head Blight of Wheat

The objective of this research was to select effective fungicides for the control of Fusarium head bight (FHB) of wheat. We tested fourteen commercial fungicides against FHB in the laboratory and under field. Fludioxonil FS, Fludioxonil SC, and Benomyl + Thiram WP highly inhibited the mycelial growth of Fusarium graminearum on the medium while Oxine-copper WP, Thiophanate-methyl WP, and Copper hydroxide WP were not effective against FHB. To verify the disease control in field condition, we selected four fungicides such as Fludioxonil SC, Captan WP, Difenoconazole + propiconazole EC, and Metconazole SC. Their control efficacy on FHB disease severity of wheat was examined after the fungicide treatment twice (30th April and 10th May, 2012) in the two field locations (Iksan and Gimje). With no treatment, FHB severity was 45% and 33.7% in Gimje and Iksan, respectively. FHB disease incidence after fungicide treatment was between 0.3% and 2.2% in Gimje, showing over 95% FHB disease control. FHB disease incidence of fungicide-treated sector in Iksan showed slightly higher than Gimje but the control value of fungicides exhibited 87-90%. No side effect of the chemicals was observed in fungicide treatment. These results showed that four fungicides were effective in the FHB disease control in wheat.

Effects on Growth and Yield Whole-crop Barley by Soil-borne Virus Infection

Barley yellow mosaic virus (BaYMV) and Barley mild mosaic virus (BaMMV) cause severe diseases in winter barley in Europe and East Asia. We investigated the effect of different level of resistance to virus disease on the plant growth and yield in whole-crop barley. In the virus infection, BaYMV was detected all tested cultivars in first diagnosis at 30th March. BaYMV infection was identified only in the susceptible Sunwoobori in 6th April, but not in the Yuyeon (moderate, M) and Youngyang (moderate resistant, MR) cultivars. Plant height was restrained about 14.6~32.9% in overwintered plant regeneration stage depending on the resistance of each cultivar. The tiller numbers also reduced to 8.7~19.7% by BaYMV infection in overwintering season. We evaluated culm length, spike length, and spike number in the virus-infected field and non-infected field. For the culm length, Youngyang (MR) reduced only 14.5% by BaYMV. However Sunwoo (susceptible, S) and Yuyeon (M) cultivars were decreased to 24.8~42.7%. The spike length and spike number also affected to 8.9~21.3% and 24.3~31.0%, respectively, depending on the resistance. After harvesting, dry-matter yield of whole crop yield reduced by approximately 21.6~58.0% according to cultivar resistant degrees. For example, Sunwoobori (S) decreased 58.0% in comparing to non-infected field. The grain yield was also significantly reduced in virus infected cultivars. Sunwoobori (S) was severely decrease more than 60.0%. Yuyeonbori (M) and Youngyangbori (MR) also decreased 30.0~47.5% by the viral infection comparing to those in the non-infected field.