• Journal of Life Science
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• v.11 no.5
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• pp.423-431
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• 2001

Genomic and cDNA clones containing the RAT3 gene involving in Agobacterium-mediated plant transformation were identified using plant DNA flanking the righ border of a T-DNA rescued from the rat3 mutant as hy-bridization probe. Two highly homologous cDNA clones were identified; one (RAT3-1) weakly hybridized with the probe whereas another (RAT3-2) strongly hybridized with the probe. Both Rat3-1 and Rat3-2 proteins contain a putative signal peptide for secretion. The deduced molecular weights of encoded proteins are 15 kDa. The results of genomic DNA blot analysis and DNA sequencing indicated that RAT3-1 and RAT3-2 exist as single copy genes and they were arranged side by side with just 600 bp distance between them. RAT3-1 was disrupted by the integration of T-DNA into the 3 untranslated region in rat3 mutant. A BLAST search showed that both RAT3-1 and RAT3-2 proteins have homology with only the C-terminal region of $\beta$-1,3-glucanase homologues from Triticum aestivum and Arabidopsis thaliana. Thses $\beta$-1,3-glucanase homologues contain an unusually long C-terminal region with no sig-nificant homology to other $\beta$-1,3-glucanase.

• The Plant Pathology Journal
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• v.31 no.3
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• pp.245-251
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• 2015

Alternative hosts increase the difficulty of disease management in crops because these alternate hosts provide additional sources of primary inoculum or refuges for diversity in the pathogen gene pool. Agropyron cristatum (crested wheatgrass), Bromus inermis (smooth bromegrass), Pascopyrum smithii (western wheatgrass), Stipa viridula (green needlegrass), and Thinopyrum intermedium (intermediate wheatgrass), commonly identified in range, prairie, verge, and soil reclamation habitats, serve as additional hosts for Pyrenophora tritici-repentis, the cause of tan spot in wheat (Triticum aestivum L.). A. cristatum (five lines), B. inermis (seven lines), P. smithii (four lines), S. viridula (two lines), and T. intermedium (six lines) were tested for their reactions to 30 representative P. tritici-repentis isolates from races 1-5. Plants were grown until the two-three-leaf stage in a greenhouse, inoculated individually with the 30 isolates, held at high humidity for 24 h, and rated after 7 days. All lines developed lesion types 1-2 (resistant) based on a 1-5 rating scale. Also, leaves from an additional plant set were infiltrated with two host selective toxins, Ptr ToxA as a pure preparation and Ptr ToxB as a dilute crude culture filtrate. All lines were insensitive to the toxins. Results indicate that these grass hosts have a limited or nonsignificant role in tan spot epidemiology on wheat in the northern Great Plains. Additionally, the resistant reactions demonstrated by the grass species in this research indicate the presence of resistance genes that can be valuable to wheat breeding programs for improving wheat resistance to P. tritici-repentis.

• Asian-Australasian Journal of Animal Sciences
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• v.25 no.10
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• pp.1374-1380
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• 2012

The changes in yields and nutritive composition of whole crop wheat (Triticum aestivum L.) during maturation and effects of maturity stage and lactic acid bacteria (LAB) inoculants on the fermentation quality and aerobic stability were investigated under laboratory conditions. Whole crop wheat harvested at three maturation stages: flowering stage, milk stage and dough stage. Two strains of LAB (Lactobacillus plantarum: LAB1, Lactobacillus parafarraqinis: LAB2) were inoculated for wheat ensiling at $1.0{\times}10^5$ colony forming units per gram of fresh forage. The results indicated that wheat had higher dry matter yields at the milk and dough stages. The highest water-soluble carbohydrates content, crude protein yields and relative feed value of wheat were obtained at the milk stage, while contents of crude fiber, neutral detergent fiber and acid detergent fiber were the lowest, compared to the flowering and dough stages. Lactic acid contents of wheat silage significantly decreased with maturity. Inoculating homofermentative LAB1 markedly reduced pH values and ammonia-nitrogen ($NH_3$-N) content (p<0.05) of silages at three maturity stages compared with their corresponding controls. Inoculating heterofermentative LAB2 did not significantly influence pH values, whereas it notably lowered lactic acid and $NH_3$-N content (p<0.05) and effectively improved the aerobic stability of silages. In conclusion, considering both yields and nutritive value, whole crop wheat as forage should be harvested at the milk stage. Inoculating LAB1 improved the fermentation quality, while inoculating LAB2 enhanced the aerobic stability of wheat silages at different maturity stages.

• Plant Biotechnology Reports
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• v.4 no.3
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• pp.213-222
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• 2010

Within their natural habitat, crops are often subjected to drought and heat stress, which suppress crop growth and decrease crop production. Causing overaccumulation of glycinebetaine (GB) has been used to enhance the crop yield under stress. Here, we investigated the response of wheat (Triticum aestivum L.) photosynthesis to drought, heat stress and their combination with a transgenic wheat line (T6) overaccumulating GB and its wild-type (WT) Shi4185. Drought stress (DS) was imposed by controlling irrigation until the relative water content (RWC) of the flag leaves decreased to between 78 and 82%. Heat stress (HS) was applied by exposing wheat plants to $40^{\circ}C$ for 4 h. A combination of drought and heat stress was applied by subjecting the drought-stressed plants to a heat stress as above. The results indicated that all stresses decreased photosynthesis, but the combination of drought and heat stress exacerbated the negative effects on photosynthesis more than exposure to drought or heat stress alone. Drought stress decreased the transpiration rate (Tr), stomatal conductance (Gs) and intercellular $CO_2$ concentration (Ci), while heat stress increased all of these; the deprivation of water was greater under drought stress than heat stress, but heat stress decreased the antioxidant enzyme activity to a greater extent. Overaccumulated GB could alleviate the decrease of photosynthesis caused by all stresses tested. These suggest that GB induces an increase of osmotic adjustments for drought tolerance, while its improvement of the antioxidative defense system including antioxidative enzymes and antioxidants may be more important for heat tolerance.

• The Plant Pathology Journal
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• v.36 no.6
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• pp.558-569
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• 2020

Fusarium head blight (FHB) is a devastating fungal disease of wheat (Triticum aestivum L.). The lack of genetic resources with stable FHB resistance combined with a reliable and rapid screening method to evaluate FHB resistance is a major limitation to the development of FHB resistant wheat germplasm. The present study utilized an immature wheat spike culture method to screen wheat spike culture derived variants (SCDV) for FHB resistance. Mycotoxin concentrations determined by liquid chromatography-tandem mass spectrometry (LC-MS/MS) correlated significantly (P < 0.01) with FHB severity and disease progression during in vitro spike culture. Selected SCDV lines assessed for FHB resistance in a Fusarium field disease nursery in Carman, Manitoba, Canada in 2016 showed significant (P < 0.01) correlation of disease severity to the in vitro spike culture screening method. Selected resistant SCDV lines were also crossed with an elite cv. CDC Hughes and the progeny of F₂ and BC₁F₂ were screened by high resolution melt curve (HRM) analyses for the wheat UDP-glucosyl transferase gene (TaUGT-3B) single nucleotide polymorphism to identify resistant (T-allele) and susceptible (G-allele) markers. The progeny from the crosses were also screened for FHB severity using the immature spike culture method and identified resistant progeny grouped according to the HRM genotyping data. The results demonstrate a reliable approach using the immature spike culture to screen for FHB resistance in progeny of crosses in early stage of breeding programs.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.67 no.4
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• pp.234-241
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• 2022

Wheat (Triticum aestivum L.) is a major staple foods and is in increasing demand in the world. The elevated temperature caused by changes in climate and environmental conditions is a major factor affecting wheat development and grain quality. The optimal temperature range for winter wheat is between 15 and 25℃, and it is necessary to study the physiological characteristic of wheat according to elevated temperatures. This study presents the effect of elevated temperature on the yield and quality of two Korean bread wheat (Baekkang and Jokyoung) in temperature gradient tunnels (TGT). Two bread wheat cultivars were grown in TGT at four different temperature conditions: T0 (control, near ambient temperature), T1 (T0+1℃), T2 (T0+2℃), (T0+2℃), T3 (T0+3℃). The period from sowing to heading stage accelerated and the number of grains per spike and grain yield reduced under T3 condition compared with those under T0 condition. Grain filling rate and grain maturity also accelerated with elevated temperature (T3). The increase in temperature led to the increase in protein contents, whereas decreased the total starch contents. These results are consistent with the decreased expression of starch synthesis genes and increased gliadin synthesis or gluten metabolism genes during the late grain filling stage. Taken together, our results suggest that the increase in temperature (T3) led to the decrease in grain yield by regulating the number of grains/spike, whereas increased the protein content by regulating the expression of starch and gliadin-related genes or gluten metabolism process genes expression. In addition, our results provide a useful physiological information on the response of wheat to heat stress.

• Asian-Australasian Journal of Animal Sciences
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• v.21 no.9
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• pp.1252-1261
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• 2008

Twenty-four yearling Boer$\times$Spanish goats were used in a crossover design experiment to determine effects of tethering on forage selection, intake and digestibility, grazing behavior and energy expenditure (EE) with forage high in nutritive value and low to moderate in mass. Objectives were to determine if tethered goats could be used as a model for study of unrestrained animals and to characterize tethering as a production practice. Four 0.72-ha pastures of wheat (Triticum aestivum) and berseem clover (Trifolium alexandrium) were grazed in December and January. Each pasture hosted six animals, three with free movement and three attached to a 4.11-m tether for access to a circular area of $53.1m^2$. Tethering areas were moved each day. One animal of each treatment and pasture was used to determine forage selection, fecal output or grazing behavior and EE; therefore, there were eight observations per treatment. Mass of forage DM before grazing in Tethered areas averaged 1,280 and 1,130 kg/ha in periods 1 and 2, respectively. The CP concentration in ingesta was greater ((p<0.05) 239 and 209 g/kg; SE = 8.0) and the NDF level was lower (p<0.05) for Free vs. Tethered animals (503 and 538 g/kg; SE = 12.0); in vitro true DM digestion was similar between treatments (0.808 and 0.807 for Free and Tethered, respectively; SE = 0.0096). Intakes of DM (1,013 and 968 g/d; SE = 78.6), NDF (511 and 521 g/d; SE = 39.9) and ME (10.9 and 10.7 MJ/d; SE = 0.90) were similar between treatments, but CP intake was greater (p<0.05) for Free vs. Tethered animals (241 and 203 g/d; SE = 17.2). There were small treatment differences in in vivo apparent digestibility of OM ((p<0.05) 0.780 and 0.814; SE = 0.0049), CP ((p<0.05) 0.800 and 0.817; SE = 0.0067) and NDF ((p<0.09) 0.777 and 0.760 for Free and Tethered, respectively; SE = 0.0078). There were no treatment effects on time spent ruminating or grazing (346 and 347 min/d for Free and Tethered, respectively; SE = 42.5), but EE was considerably greater (p<0.05) for Free vs. Tethered animals (571 and 489 kJ/kg $BW^{0.75}$; SE = 8.9). In conclusion, with forage of high nutritive value and low to moderate in mass, tethering can offer a production advantage over free grazing of less energy used for activity despite similar grazing time. With forage removal considerably less than that available for grazing, effects of tethering on chemical composition of selected forage were small and less than needed to markedly affect digestion. Tethering may offer a means of studying some aspects of grazing by ruminants, but would not seem suitable for energy metabolism.

• Korean Journal of Weed Science
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• v.15 no.1
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• pp.54-62
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• 1995

Acetolactate synthase activity inhibition and herbicidal activities were investigated with 2 sulfonylureas [chlorsulfuron{2-chloro-N-{{(4-methoxy-6-methyl-1,3,5-triazin-2-yl) amino} carboxyl} benzenesulfonamide}, metsulfuron-methyl{methyl-2{{{{(4-methoxy-6-methyl-1,3,5-triazin-2-yl)amino}carbonyl}amino}sulfonyl}benzoic acid}, and 2 imidazoli-nones [imazethapyr{2-{4,5-dihydro-4-methyl-4-(1-methyl)-5-oxo-1H-imidazol-2-yl}-5-ethyl-3-pyridinecarboxylicacid}, imazaquin{2-{4,5-dihydro-4-methyl-4-(1-methyl)-5-oxo-1H-imidazol-2-yl}-3-quinoline carboxylic acid} herbicides. A broad weeding spectrum was observed with the treated herbicides at low application rates. Both corn(Zea mays L.) and sorghum(Sorghum bicolor Moench) were very sensitive to the two herbicide groups. Although legumes, such as soybean(Glycine max Merr.), clover(Trifolium repense L.), and indian jointvetch(Aeschnomene indica L.) were sensitive to the sulfonylureas, they were tolerant to the imidazolinones. On the contrary, wheat(Triticum aestivum L.) and barley(Hoderum sativum Jess.) showed the reverse responses of the legumes to the two herbicide groups. Quackgrass(Agropyron repens(L.) P. Beauv.). however, was commonly tolerant to the two herbicide groups. Degrees of crop injury and acetolactate synthase inhibition also varied with the crops examined. The 50% inhibition concentrations of sulfonylureas on acetolactate synthase in vitro activity($IC_{50}$) from corn, wheat, and soybean did not relate to the greenhouse herbicidal activities ($GI_{50}$). With chlorsulfuron, for example, wheat had more than 100 times higher $GI_{50}$ than corn and soybean, but the $IC_{50}$ was 4 to 10 times lower. Similar observation was made with metsulfuron-methyl. However, closer relationships between $IC_{50}$ and $GI_{50}$ were found with the imidazolinones. When imazethapyr was applied, the order of $GI_{50}$ values against com, wheat, and soybean was the same as that of $IC_{50}$.