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Iseo, South Korea

Huang J.,Gyeongsang National University | Kim C.M.,University of Oxford | Xuan Y.-H.,Gyeongsang National University | Liu J.,Gyeongsang National University | And 3 more authors.

The outgrowth of root hairs from the epidermal cell layer is regulated by a strict genetic regulatory system and external growth conditions. Rice plants cultivated in water-logged paddy land are exposed to a soil ecology that differs from the environment surrounding upland plants, such as Arabidopsis and maize. To identify genes that play important roles in root-hair growth, a forward genetics approach was used to screen for short-root-hair mutants. A short-root-hair mutant was identified, and the gene was isolated using map-based cloning and sequencing. The mutant harbored a point mutation at a splicing acceptor site, which led to truncation of OsFH1 (rice formin homology 1). Subsequent analysis of two additional T-DNA mutants verified that OsFH1 is important for root-hair elongation. Further studies revealed that the action of OsFH1 on root-hair growth is dependent on growth conditions. The mutant Osfh1 exhibited root-hair defects when roots were grown submerged in solution, and mutant roots produced normal root hairs in the air. However, root-hair phenotypes of mutants were not influenced by the external supply of hormones or carbohydrates, a deficiency of nutrients, such as Fe or Pi, or aeration. This study shows that OsFH1 plays a significant role in root-hair elongation in a growth condition-dependent manner. © 2013 Springer-Verlag Berlin Heidelberg. Source

Son J.-H.,Kangwon National University | Park K.-C.,Kangwon National University | Kim T.-W.,Kangwon National University | Park Y.-J.,Kongju National University | And 2 more authors.
Genes and Genomics

Allium is a very diverse genus with over 600 species distributed worldwide. Haplotype analyses of 45S rRNA ITS, trnH-psbA spacer, and matK gene sequences in 9 Allium species were carried out, subsequent to which phylogenetic relations of the nine species were also analyzed. Of the three genes, the nuclear 45S rRNA ITS sequences showed the highest variation with one haplotype In each species. The other two chloroplast genes revealed that more than one haplotype was present in each species, and each haplotype was present in several of the species. In the matK gene, EcoRI restriction revealed heteroplasmy in which the functional gene retains the EcoRI recognition site while the nonfunctional, pseudogene does not. Phylogenetic patterns were not consistent among the haplotypes of the 45 rRNA ITS, trnH-psbA spacer, and matK genic regions. This phylogenetic incongruency might be due to the presence of multiple haplotypes in each of the chlor-oplast genes. However, the inconsistency of the phylogenetic relationships, based on the 45S rRNA ITS sequences makes a strong case for further analysis. © The Genetics Society of Korea and Springer 2010. Source

Mondal A.B.,BPATC | Al Mamun A.,RDA
Frontiers of Agriculture in China

To study the effect of foliar application of urea fertilizer on the growth and yield of tomato and to find out the optimum concentration of foliar application of urea for maximum growth and yield of tomato, an experiment was conducted with different concentrations of foliar application of urea fertilizer, namely, 2500, 5000, 7500, and 10000 ppm. The experiment was laid out by a randomized complete block design (RCBD) with four replications. Results showed that different yield components and yield of tomato were influenced by the foliar application of different concentrations of urea. The maximum plant height (132. 6 cm), number of leaves (30. 73), number of green leaves per plant at harvest (21. 08), days to first flowering (28. 94), number of flower clusters (11. 89), number of flowers (75. 18), fruit clusters (5. 81), fruits per cluster (4. 14), and fruits per plant (21. 49); length (4. 72 cm), diameter (6. 58 cm), and weight of individual fruit (151. 0 g) were significantly influenced by the 10000 ppm concentration of foliar application of urea fertilizer. The 10000 ppm application gave the highest yield (63. 69 t/hm2) with the lowest (28. 48 t/hm2) in the control treatment. The yield per plant as well as per hectare increased with increasing concentrations of foliar application of urea fertilizer. © 2011 Higher Education Press and Springer-Verlag Berlin Heidelberg. Source

Kim J.Y.,Gyeongsang National University | Lee W.S.,Korea Research Institute of Bioscience and Biotechnology | Kim Y.S.,Gyeongsang National University | Curtis-Long M.J.,12 New Road | And 3 more authors.
Journal of Agricultural and Food Chemistry

Cholinesterases are key enzymes that play important roles in cholinergic transmission. Nine flavonoids displaying cholinesterase inhibitory activity were isolated from the root bark of Morus lhou L., a cultivated edible plant. The isolated compounds were identified as a new flavone (1), 5′-geranyl-5,7, 2′,4′-tetrahydroxyflavone (2), kuwanon U (3), kuwanon E (4), morusin (5), morusinol (6), cyclomorusin (7), neocyclomorusin (8), and kuwanon C (9). All compounds apart from compound 6 inhibited cholinesterase enzyme in a dose-dependent manner with Ki values ranging between 3.1 and 37.5 μMand between 1.7 and 19.1 μM against acetylcholinesterase (AChE) and butyrylcholinesterase (BChE) enzymes, respectively. The new compound was charactierized as 5′-geranyl-4′-methoxy-5,7,2′- trihydroxyflavone (1). It showed the most potent inhibitory activity (Ki = 3.1 μM for AChE, Ki = 1.74 μMfor BChE). Lineweaver-Burk and Dixon plots and their secondary replots indicated that flavones (5-9) with prenyl substitution on C-3 were noncompetitive inhibitors, whereas those unsubstituted (1-4) at C-3 were mixed inhibitors of both AChE and BChE. In conclusion, this is the first study to demonstrate that alkylated flavonoids of M. lhou have potent inhibitory activities against AChE and BChE. © 2011 American Chemical Society. Source

Huang J.,Gyeongsang National University | Kim C.M.,University of Oxford | Xuan Y.-H.,Gyeongsang National University | Park S.J.,Gyeongsang National University | And 6 more authors.
Plant Molecular Biology

Rice is cultivated in water-logged paddy lands. Thus, rice root hairs on the epidermal layers are exposed to a different redox status of nitrogen species, organic acids, and metal ions than root hairs growing in drained soil. To identify genes that play an important role in root hair growth, a forward genetics approach was used to screen for short-root-hair mutants. A short-root-hair mutant was identified and isolated by using map-based cloning and sequencing. The mutation arose from a single amino acid substitution of OsSNDP1 (Oryza sativa Sec14-nodulin domain protein), which shows high sequence homology with Arabidopsis COW1/AtSFH1 and encodes a phosphatidylinositol transfer protein (PITP). By performing complementation assays with Atsfh1 mutants, we demonstrated that OsSNDP1 is involved in growth of root hairs. Cryo-scanning electron microscopy was utilized to further characterize the effect of the Ossndp1 mutation on root hair morphology. Aberrant morphogenesis was detected in root hair elongation and maturation zones. Many root hairs were branched and showed irregular shapes due to bulged nodes. Many epidermal cells also produced dome-shaped root hairs, which indicated that root hair elongation ceased at an early stage. These studies showed that PITP-mediated phospholipid signaling and metabolism is critical for root hair elongation in rice. © 2013 Springer Science+Business Media Dordrecht. Source

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