• Research in Plant Disease
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• v.12 no.1
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• pp.62-64
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• 2006

July in 2005, we collected infected maize plant that showing stripe dwarf disease on maize leaf in Jeonbuk provinces including Gochang-gun and conducted genomic dsRNA extraction and RT-PCR. Genomic dsRNA was extracted directly in infected maize plant and electrophoresis in agarose gel. We confirmed 10 segments of genomic dsRNA. We conducted RT-PCR by genomic dsRNA and specific primer of S7, S8 and S10. As a result, specific band of expected size was confirmed respectively. In the results of dsRNA and RT-PCR analysis, we confirmed Rice black-streaked dwarf fijivirus (RBSDV) from naturally infected maize plant. Occurrence of RBSDV of maize plant was dealt 22 ha's damage in maize field. The occurrence rate was 80% in a lot of places of disease.

• Research in Plant Disease
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• v.29 no.2
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• pp.137-144
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• 2023

Exserohilum turcicum is a fungus that causes northern corn leaf blight (NCLB) and has deleterious effects on maize production globally. Therefore, it is prudent to mitigate the effects of NCLB using genetic diversity. The objective of this research was to assess the severity of NCLB disease on the growth and yield of various maize genotypes. A randomized complete block design field experiment, replicated three times, was conducted to evaluate the effect of E. turcicum on 10 maize hybrids. Percent disease index, plant height, and leaf area were recorded at the silk stage. Cob weight, grain fresh weight, and grain yields were determined at harvest maturity. All measured parameters were significantly different (P<0.05) between the maize hybrids. Of the 10 genotypes, four (PAN 4R-528R, PAN 4R-728BR, PAN 3R-724BR, and P1788BR) were susceptible, five (DKC74-74BR, PAN 5R-582R, PAN 5R-890R, PAN 5R-854R, and PAN 5R-590R) were moderately susceptible, and one (DKC80-40BR) was moderately resistant. DKC80-40BR exhibited greater cob weight, while DKC74-74BR was superior in all other plant growth and yield components. Interestingly, although not significant (P>0.05) and high, maize growth and yield parameters had negative correlations with disease incidence, except for grain fresh weight. Therefore, DKC80-40BR may be selected for cultivation in areas prone to NCLB to reduce maize susceptibility to the disease, while DKC74-74BR may improve crop performance. These hybrids could be considered as potential sources of resistance or tolerance to NCLB for further validation by plant breeders.

• Korean Journal of Food Science and Technology
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• v.48 no.2
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• pp.165-171
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• 2016

Physicochemical properties of waxy maize flours prepared by hydrothermal and enzymatic treatments were evaluated. Waxy maize flours were hydrothermally treated using heat-moisture treatment (HMT) and annealing (ANN) and enzymatically treated using commercial enzymes (cellulase, proteinase, and pectinase). The HMT-modified waxy maize flours had low water absorption index (WAI), melting enthalpy, viscosity, and crystallinity. However, ANN-modified and enzymatically modified waxy maize flours had high WAI, melting enthalpy, and viscosity. X-ray diffraction analysis of ANN-modified and enzymatically modified waxy maize flours revealed a typical A-type pattern and displayed sharper crystalline peaks than those observed for the control groups (native waxy maize flours). In contrast, the crystallinity of HMT-modified waxy maize flours were decreased by hydrothermal treatment.

• Journal of Environmental Science International
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• v.19 no.12
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• pp.1323-1334
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• 2010

The effect of nitric oxide (NO) on antioxidant system and protective mechanism against oxidative stress under UV-B radiation was investigated in leaves of maize (Zea mays L.) seedlings during 3 days growth period. UV-B irradiation caused a decrease of leaf biomass including leaf length, width and weight during growth. Application of NO donor, sodium nitroprusside (SNP), significantly alleviated UV-B stress induced growth suppression. NO donor permitted the survival of more green leaf tissue preventing chlorophyll content reduction and of higher quantum yield for photosystem II than in non-treated controls under UV-B stress, suggesting that NO has protective effect on chloroplast membrane in maize leaves. Flavonoids and anthocyanin, UV-B absorbing compounds, were significantly accumulated in the maize leaves upon UV-B exposure. Moreover, the increase of these compounds was intensified in the NO treated seedlings. UV-B treatment resulted in lipid peroxidation and induced accumulation of hydrogen peroxide ($H_2O_2$) in maize leaves, while NO donor prevented UV-B induced increase in the contents of malondialdehyde (MDA) and $H_2O_2$. These results demonstrate that NO serves as antioxidant agent able to scavenge $H_2O_2$ to protect plant cells from oxidative damage. The activities of two antioxidant enzymes that scavenge reactive oxygen species, catalase (CAT) and ascorbate peroxidase (APX) in maize leaves in the presence of NO donor under UV-B stress were higher than those under UV-B stress alone. Application of 2-(4-carboxyphenyl)-4, 4, 5, 5-tetramethylimidazoline-1-oxyl-3- oxide (PTIO), a specific NO scavenger, to the maize leaves arrested NO donor mediated protective effect on leaf growth, photosynthetic pigment and free radical scavenging activity. However, PTIO had little effect on maize leaves under UV-B stress compared with that of UV-B stress alone. $N^{\omega}$-nitro-L-arginine (LNNA), an inhibitor of nitric oxide synthase (NOS), significantly increased $H_2O_2$ and MDA accumulation and decreased antioxidant enzyme activities in maize leaves under UV-B stress. This demonstrates that NOS inhibitor LNNA has opposite effects on oxidative resistance. From these results it is suggested that NO might act as a signal in activating active oxygen scavenging system that protects plants from oxidative stress induced by UV-B radiation and thus confer UV-B tolerance.

• Research in Plant Disease
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• v.23 no.3
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• pp.278-282
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• 2017

Maize is one of the most cultivated cereals as a staple food in the world. The harvested maize is mainly stored after drying, but its quality and nutrition could be debased by fungal spoilage and mycotoxin contamination. In this study, we surveyed mycotoxin contamination fungal infection of maize kernels that were stored for almost one year after harvest in 2015. The amount of deoxynivalenol and zearalenone detected were higher than the other mycotoxin, such as aflatoxin, ochratoxin, fumonisin and T-2 toxin. In particular, level of deoxynivalenol was detected as $1200{\pm}610{\mu}g/kg$ in small size kernels, which was four to six times higher than the large and the medium size kernels. Moreover, the amount of deoxynivalenol, zearalenone, and fumonisin were increased with discolored kernels. 10 species including Fusarium spp., Aspergillus spp. and Penicillium spp. were isolated from the maize kernels. F. graminearum was predominant in the discolored kernels with detection rates of 60% (red) and 40% (brown). Our study shows that the mycotoxin contents of stored maize can be increased by discolored maize kernels mixed. Therefore elimination of the contaminated maize kernels will help prevent fungal infection and mycotoxin contamination in stored maize.

• Asian-Australasian Journal of Animal Sciences
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• v.16 no.6
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• pp.843-851
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• 2003

An experiment was conducted to investigate the effects of pre-wilting Bana grass (Pennisetum purpureum x P. americanum) herbage under sunny conditions for 0, 6, 18, 24, 32 and 48 h and ensiling it with maize meal. Four levels of maize meal(viz., 0, 5, 10 and 15% on fresh weight (Fw) basis) were tested. The experiment had a split-plot design. Wilting increased the concentration of water soluble carbohydrates (WSC) significantly (p<0.001) on a Fw basis, although there were no significant changes on DM basis. Unwilted grass contained $36.1g{\cdot}WSC{\cdot}kg^{-1}{\cdot}Fw$ ($127.6g{\cdot}kg^{-1}{\cdot}DM$) and this increased to $64.1g{\cdot}WSC{\cdot}kg^{-1}{\cdot}Fw$ ($116.7g{\cdot}kg^{-1}{\cdot}DM$) after 48 h of pre-wilting. Wilting also increased the DM content of herbage significantly (p>0.001) from 250 to $620g{\cdot}kg^{-1}$, between 0 and 48 h respectively. The concentration of fermentation end-products decreased (except butyric acid) and pH increased when the period of wilting increased, indicating that fermentation was restricted. In particular, lactic acid content declined from 50.8 to $26.2g{\cdot}kg^{-1}{\cdot}DM$ (p<0.01) and the residual WSC contents of silage increased from 2.7 with fresh herbage to $18.1g{\cdot}kg^{-1}{\cdot}DM$ with 48 h of wilting (p<0.001). Rapid wilting for 24 h, to a DM of $450g{\cdot}kg^{-1}$ was optimum since important increases in pH, residual WSC and DMD occurred at this level of wilting. Acetic acid, butyric acid and ammoniacal-N contents were lowest with 24 h of wilting. There were no significant interactions between length of wilting and the incorporation of maize meal. Wilting had a greater influence on fermentation than the incorporation of maize meal. Addition of maize meal facilitated fermentation by increasing forage DM content and reducing effluent production. In addition, the maize meal increased DMD. It was concluded that maize meal should generally be incorporated at a level of 5% on fresh weight basis.

• Asian-Australasian Journal of Animal Sciences
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• v.3 no.3
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• pp.161-164
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• 1990

Ninety six Rambouillet ${\times}$ Kaghani intact male lambs of 18 months of age were divided into 6 groups of 16 lambs each, groups being G-1, G-2, G-3, G-4, G-5 and G-6. Average liveweight of animals on different treatments at day 0 of the experiment was G-1 (24.68 S.D 3.35), G-2 (24.56 S.D 2.55), G-3 (24.53 S.D 2.90), G-4 (24.51 S.D 3.38), G-5 (24.58 S.D 3.58) and G-6 (24.81 S.D 3.43). Animals on treatment G-1 were fed only maize silage ad libitum, G-2 had been offered maize silage ad libitum plus 4.8 kg of commercial concentrate (Sona Vanda) per group, G-3 maize silage ad libitum plus 4.8 kg of crushed maize grain per group. G-4 lambs were fed oat silage ad libitum plus 4.8 kg of crushed maize per group, G-5 oat silage plus 4.8 kg of commercial concentrate per group and G-6 only oat silage ad libitum. The results showed highly significant differences (p<0.01) among treatment groups in silage intake throughout the feeding trial. G-2 group showed the highest silage intake while treatment G-4 showed the lowest silage intake for the first two months and treatment G-6 for the last two months. The results of growth rates (g/d/animal) showed that treatments G-1 and G-6, where no supplementation was given, had a weight loss throughout the feeding trial. However, weight loss in treatment G-6 was more severe than treatment G-1. Treatments G-2, G-3, G-4 and G-5 all showed weight gain however, treatment G-2 had the most gain. G-2 group also showed the highest wool production while G-6 the lowest. These results indicated that silage when made from full bloom crops of oats and silage fed alone without any supplementation causes weight loss in sheep. Supplementation with concentrates having 19% CP is far better than the crushed maize grain and maize silage is better than oats silage. Maize silage is superior than oat silage however, better performance could be expected if silages were made at the early bloom (dough) stage of plant maturity. The results indicate that treatment G-2 shows highest response while treatment G-6 the lowest. So the response of different treatments on both the parameters of weight gain and wool production is almost similar.

• Asian-Australasian Journal of Animal Sciences
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• v.19 no.6
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• pp.892-897
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• 2006

An experiment was designed to study the nutritional value of Chinese brown rice and maize for growing pigs. Six male grower pigs (Duroc${\times}$Landrace${\times}$Large White, $24.3{\pm}1.26$ kg average initial BW) were surgically fitted with a simple T-cannula at the terminal ileum and allotted within a $2{\times}2$ Latin square design. The pigs were fed either a maize or brown rice diet in a direct method to determine their digestibility. The brown rice used in this experiment was husked from one kind of early, long grain, and non-glutinous rice (ELGNR, indica rice: non-waxy rice, containing amylopectin and amylose) in southern China. Chromic oxide was used as a marker. The diets were supplied at about 4.0% of body weight in dry matter/d. Total faeces and urine were collected on days 4 and 5; digesta was collected on days 6-8 in each period. The average body weight was 24.3 kg at the start of the experiment and 27.6 kg at the end. The results showed that the apparent ileal digestibilities of most amino acids of brown rice were significantly higher than those in maize (p<0.01), as were the apparent ileal digestibilities of crude protein (CP), digestible energy (DE), organic matter (OM) and dry matter (DM) (p<0.05). However, the apparent ileal starch digestibilities of the two treatments were similar (p>0.05). The values of the apparent faecal digestibilities derived from the two methods, marker and total faecal-collection methods, were very similar and also correlated with each other. The difference in absolute value of the apparent faecal digestibilities between brown rice and maize was smaller compared to that of the apparent ileal digestibilities. The net protein utilization was higher (p = 0.07) and the DE metabolizable rate was significantly higher (p<0.01) for brown rice than for maize. The metabolizable energy (ME) of brown rice is similar to that of maize, while the DE of brown rice was relatively lower. It can be concluded that Chinese brown rice are better than maize not only in apparent ileal digestibilities, but also in metabolizable rate of amino acids and gross energy under the present study conditions.

• Korean Journal of Food Science and Technology
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• v.30 no.1
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• pp.42-48
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• 1998

Physicochemical properties of waxy maize starch and oxidized waxy maize starch with sodium hypochlorite $(0{\sim}60\;mg\;CL_2/g\;starch,40^{\circ}C,\;pH\;10,\;3.0\;hr)$ were studied. As sodium hypochlorite concentration was increased, the content of crude lipid and crude protein of the oxidized starch were decreased. And crude protein content and whiteness was considered to show negative regression. However, the crude ash content of the oxidized starch increased significantly with oxidation and bore a positive regression to the chlorine content. There was a progressive increase in the carboxyl content with increasing oxidant level. After pasting in hot water and cooling, viscosity of the oxidized starches were drastically lower than that of native starch . As carboxyl contents of the oxidized starch increased, the solubility and swelling power was increased. When waxy maize starch treated with 0, 1.5, 3.0 and 6.0% sodium hypochlorite, temperature of initial gelatinization of oxidized starch was shown to 65, 65, 60 and $50^{\circ}C$, respectively. The oxidized waxy maize starches also form clearer pastes. Water binding capacity of the oxidized starch decreased as the degree of carboxyl group substitution increased. Waxy maize starch has polygonal and some round granules which range from about 3.7 to $20\;{\mu}m$ in diameter. Surface appearance of the waxy maize starch became rough when oxidized with sodium hypochlorite. When homogenate of the oxidized waxy maize starch solution and corn germ oil was stored under room temperature for 24 hours, the emulsion stability was considered to depend on starch concentration and degree of substitution.

• Korean Journal of Soil Science and Fertilizer
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• v.33 no.3
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• pp.182-192
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• 2000

The objective of this study was to determine the effects of various kinds of composts on the amount of maximum composts in upland soils. Field experiments were conducted in the loam and sandy loam soils. Various kinds of composts such as poultry manure compost(PMC), cow manure compost(CMC), human excrement sludge(HES), and food industrial sludge compost(FISC) were applied annually at rates of 0, 40, and $80Mg\;ha^{-1}$ to soils grown with soybean and maize plants for 4 years during 1994 to 1997. The results of this study were as follows : Maize dry matter production was related linearly positively with application amount of compost, but soybean dry matter production was showed an apex at $60Mg\;ha^{-1}$, maize produced 4.7 times dry matter as compared to soybean. Rate of nitrogen utilization of maize were 21~31% and that of soybean were 8~19%, rate of phosphorous utilization of maize were 5~7% and that of soybean were l~2%. On the basis of biomass maximum application rates of poultry manure compost were $39{\sim}47Mg\;ha^{-1}$ for maize cultivation and $8{\sim}13Mg\;ha^{-1}$ for soybean cultivation. On the other hand those amounts estimated by nitrogen requirement of crops were 39~47 and $8{\sim}13Mg\;ha^{-1}$ for maize and soybean cultivation, respectively. Based on phosphorous requirement of crops those were 29 and $14Mg\;ha^{-1}$ for maize and soybean cultivation, respectively. Considering the upper limit of the base saturation percentage to be 80%, maximum application rates were 63~93 and $49{\sim}69Mg\;ha^{-1}$ in loam and sandy loam soil, respectively.