Performance of polymer-coated urea in transplanted rice: effect of mixing ratio and water input on nitrogen use efficiency     

Mukund D. Patil  Bhabani S. Das  Eran Barak  Pratap B. S. Bhadoria  Amir Polak 《Paddy and Water Environment》2010,8(2):189-198

Polymer-coated urea (PCU) is an important alternative to uncoated urea for improving nitrogen (N) use efficiency (NUE). Only a few studies discuss their utility for lowland rice systems. A 2-year field study was conducted to examine if nitrogen loading is reduced in lowland rice ecosystem by using mixture of PCU and uncoated urea without sacrificing yield. Five treatments involving two mixtures of PCU with 50 and 70% coated urea each at 70 and 50% of recommended dose (80 kg N ha⁻¹) and one with uncoated urea at 100% recommended dose were laid out in a completely randomized design. Selected plant growth parameters and plant available N contents (NH₄–N plus NO₃–N) in soil solution and ponded water were measured over a period of 65 days after transplanting. Results showed no significant difference for vegetative and yield parameters among different treatments suggesting that treatments receiving lower doses of nitrogen exhibited higher NUE. Analysis of partial factor of productivity (PFP) for N suggested that the total N dose may be reduced by 50% using mixtures of coated and uncoated urea. Similarly, statistically similar PFP values for treatments receiving the same amount of total N for both years and for both total N dose suggested that the proportion of coated urea may also be reduced to as low as 50% without sacrificing yield. Correlation analysis on nitrogen contents in ponded water and soil solutions and the analysis of water productivity and PFP showed that soil water regime could also significantly influence the nitrogen status in soil even when PCU are applied. In turn, both the water regime and N contents in soil ultimately influences grain yield. Although the constant release of N from coated fertilizer ensures adequate N supply for plant uptake, it may not completely avoid N deficit condition especially during heavy rainfall. Analysis of the developed production function suggested that 55–65% polymer coating and about 100 cm total water input may be ideal for achieving maximum yield. The production function was developed for PCU treatments using data observed in treatments receiving 70% recommended N dose. The range of water input in these treatments was 86.5–174.0 cm.  相似文献   

竹绿虎天牛溴甲烷熏蒸处理技术研究     

余道坚  焦懿  陈志奔  康林  杨伟东  陈枝楠  章桂明  詹国平  Alan  V．Barak 《中国农学通报》2009,(3)

1985～2005年,美国报道从我国出口的竹制品中发现包括竹绿虎天牛(Chlorophorus annularis F.)在内的20多种有检疫意义的害虫.由于目前还没有针对竹制品中竹绿虎天牛的熏蒸处理技术指标,美国APHIS-PPQ采用其检疫处理手册的T404-d方案对竹制品进行熏蒸处理,即溴甲烷熏蒸24h.美国采用的竹制品熏蒸方案中溴甲烷的用量较高,本文应用比T404～d方案更低剂量的溴甲烷,研究竹桩中竹绿虎天牛的熏蒸效果.溴甲烷熏蒸试验在自制的小型熏蒸箱中进行,在26.7℃48 g/m3、21.1℃ 64 g/m3、15.6℃ 80 g/m3、10.0℃ 96 g/m3和4.4℃ 112 g/m3等5个温度和剂量组合,共20个试验(每个剂量4个重复)共熏蒸处理2847头幼虫、140头蛹和122头成虫,死亡率达100%,而在3组对照中共发现455头活虫.同时,用装满竹杆(80%)的20尺集装箱模拟竹制品出口熏蒸试验,以检查在24h的熏蒸过程中溴甲烷是否保持必需的浓度要求.本研究推荐了较低剂量的溴甲烷熏蒸处理竹制品的新的技术指标.  相似文献   

Role of CXCR4 and SDF-1 in mammary tumor metastasis in the cat   总被引：2，自引：0，他引：2  

Oonuma T  Morimatsu M  Nakagawa T  Uyama R  Sasaki N  Nakaichi M  Tamamura H  Fujii N  Hashimoto S  Yamamura H  Syuto B 《The Journal of veterinary medical science / the Japanese Society of Veterinary Science》2003,65(10):1069-1073

It has recently been suggested that the chemokine receptor CXCR4 and its ligand SDF-1 (CXCL12) promote metastasis of various cancers in humans. Since feline mammary tumors also metastasize to distant organs frequently, we used real-time quantitative PCR to examine the expression of feline CXCR4 (fCXCR4) in ten feline mammary tumor cell lines and seven feline mammary tumor tissues, and also the expression of feline SDF-1 (fSDF-1) in various organs. Cell lines derived from metastatic regions expressed more fCXCR4 than those derived from primary tumors. Mammary tumor tissues overexpressed more fCXCR4 than normal mammary tissues. Organs with high levels of fSDF-1 expression represent common sites of metastasis. Migration assays using the feline mammary tumor cell line NAC were also performed to test the activity of TN14003 and TC14012, antagonists of human CXCR4, to antagonize fCXCR4 expressed on NAC cells. TN14003 and TC14012 inhibited migration of NAC cells. We conclude that fCXCR4 may be a therapeutic target for feline mammary tumors.  相似文献   

Lipid peroxidation and coupled vitamin oxidation in simulated and human gastric fluid inhibited by dietary polyphenols: health implications     

Gorelik S  Lapidot T  Shaham I  Granit R  Ligumsky M  Kohen R  Kanner J 《Journal of agricultural and food chemistry》2005,53(9):3397-3402

The Western diet contains large quantities of oxidized lipids, because a large proportion of the food in the diet is consumed in a fried, heated, processed, or stored form. We investigated the reaction that could occur in the acidic pH of the stomach and accelerate the generation of lipid hydroperoxides and cooxidation of dietary vitamins. To estimate the oxygen content in the stomach after food consumption, oxygen released from masticated bread (20 g) into deoxygenated water (100 mL) was measured. Under these conditions, the oxygen concentration rose by 250 microM and reached a full oxygen saturation. The present study demonstrated that heated red meat homogenized in human gastric fluid, at pH 3.0, generated hydroperoxides and malondialdehyde. The cross-reaction between free radicals produced during this reaction cooxidized vitamin E, beta-carotene, and vitamin C. Both lipid peroxidation and cooxidation of vitamin E and beta-carotene were inhibited at pH 3.0 by red wine polyphenols. Ascorbic acid (44 mg) at a concentration that represented the amount that could be ingested during a meal inhibited lipid peroxidation only slightly. Red wine polyphenols failed to prevent ascorbic acid oxidation significantly but, in conjunction with ascorbic acid, did inhibit lipid peroxidation. In the presence of catechin, a well-known polyphenol found in red wine, ascorbic acid at pH 3.0 works in a synergistic manner preventing lipid peroxidation and beta-carotene cooxidation. The present data may explain the major benefits to our health and the crucial role of consuming food products rich in dietary antioxidants such as fruits, vegetables, red wines, or green tea during the meal.  相似文献   

The effect of sodium butyrate supplementation on ruminal and fecal pH and serum lipopolysaccharide-binding protein after ruminal acidosis challenge in nonlactating cows     

Rika Fukumori  Rina Ikeno  Kenichi Izumi  Kazuya Doi  Marina Otsuka  Kazuyuki Suzuki  Shin Oikawa 《Animal Science Journal》2021,92(1):e13673

The objective of this study was to evaluate effects of sodium-butyrate supplementation on gastrointestinal function and the inflammatory response to ruminal acidosis (RA) challenge in cows. Four nonlactating cows with a rumen cannula were assigned to two treatments in a crossover design. Treatments were ruminal administration of sodium-butyrate (BUT) or control (CON). Sodium-butyrate was provided as Gustor BP70 and administered at a butyrate dose of 0.04% per kg body weight. The CON premix was made by replacing sodium-butyrate with wheat bran. Experimental periods were 28 days long with 21-day washout period separating the treatments. On Day 25 of each period, corn starch was ruminally administered at 0.7% per kg body weight as RA challenge. After RA challenge, ruminal pH was lower, and endotoxin concentration was higher for cows provided with BUT than those with CON, but the increase in fecal starch and the decrease in fecal pH were attenuated by BUT. The effect of butyrate supplementation on serum lipopolysaccharide-binding protein after RA challenge was not found. From these findings, butyrate supplementation mitigated rectal acidosis by reducing the flux of fermentable carbohydrate into the large intestine. An anti-inflammatory effect of butyrate was not observed, possibly due to lower pH and higher endotoxin concentration in the rumen.  相似文献   

Finding functional features in Saccharomyces genomes by phylogenetic footprinting     

Cliften P  Sudarsanam P  Desikan A  Fulton L  Fulton B  Majors J  Waterston R  Cohen BA  Johnston M 《Science (New York, N.Y.)》2003,301(5629):71-76

  相似文献   

Beta-arrestin 2 regulates zebrafish development through the hedgehog signaling pathway     

Wilbanks AM  Fralish GB  Kirby ML  Barak LS  Li YX  Caron MG 《Science (New York, N.Y.)》2004,306(5705):2264-2267

beta-arrestins are multifunctional proteins that act as scaffolds and transducers of intracellular signals from heptahelical transmembrane-spanning receptors (7TMR). Hedgehog (Hh) signaling, which uses the putative 7TMR, Smoothened, is established as a fundamental pathway in development, and unregulated Hh signaling is associated with certain malignancies. Here, we show that the functional knockdown of beta-arrestin 2 in zebrafish embryos recapitulates the many phenotypes of Hh pathway mutants. Expression of wild-type beta-arrestin 2, or constitutive activation of the Hh pathway downstream of Smoothened, rescues the phenotypes caused by beta-arrestin 2 deficiency. These results suggest that a functional interaction between beta-arrestin 2 and Smoothened may be critical to regulate Hh signaling in zebrafish development.  相似文献   

Erwinia carotovora subsp.atroseptica infection promotes verticillium wilt development in potato in Israel     

Leah Lahkim Tsror  A. Nachmias  L. Livescu  M. C. M. Perombelon  Z. Barak 《Potato Research》1990,33(1):3-11

Summary The interaction betweenErwinia carotovora subsp.atroseptica (Eca) andVerticillium dahliae and its effect on symptom development in potato cultivars showing different degrees of resistance to them was examined over two seasons in irrigated fields in a hot, dry climate. Four cultivars were used: Cara, highly resistant to blackleg and tolerant to Verticillium wilt; Pentland Crown also resistant to blackleg but susceptible to Verticillium wilt; Désirée, moderately susceptible to blackleg but tolerant to Verticillium wilt; and Maris Bard, susceptible to both diseases. Seed tubers were inoculated with Eca immediately after harvest in Scotland, to simulate natural infection, and then planted in Israel in soil naturally infested byV. dahliae. In Verticillium tolerant cultivars, Eca infection increased the rate of colonization byV. dahliae and significantly enhanced symptom development, as assessed by suppression of plant height and wilt symptoms. This report is a portion of the Ph.D. thesis of the senior author in Ben-Gurion University of the Negev.  相似文献   

A natural two-nucleotide deletion affirms role for NADPH oxidase in pathogenicity and perithecium formation in Fusarium graminearum species complex     

Haruhisa Suga  Rina Okumura  Maho Ikawa  Masafumi Shimizu  Koji Kageyama 《Plant pathology》2022,71(3):602-610

Members of the Fusarium graminearum species complex are known to cause head blight of wheat. A natural nonpathogenic mutant, strain Fa0233007, was found in the strain collection of the Japanese F. graminearum species complex. In addition, this strain cannot form perithecia. Complete linkage of these deficiencies in the progenies obtained from crossing a wild-type strain and the mutant strain suggested that a single genomic locus was responsible for deficiencies in both traits. The locus was mapped to chromosome 1 using sequence-tagged markers. An NADPH oxidase gene (NoxA, FGSG00739) was identified in the mapped region, and a 2-bp deletion that results in premature termination of the open reading frame was detected in the gene. Both pathogenicity and perithecium formation were recovered by FGSG00739 complementation in the mutant strain.  相似文献   

植物乳杆菌的生理功能和组学研究进展     

曹承旭  郭晶晶  乌日娜  岳喜庆 《乳业科学与技术》2018,41(1):33-39

植物乳杆菌是乳酸杆菌的一种,在自然界中广泛存在,尤其是各类发酵食品中。植物乳杆菌是人体肠道微生物的一员,由其生产的发酵食品的发酵作用与其对人体的益生作用使得植物乳杆菌逐渐成为基因组学、蛋白质组学、转录组学和代谢组学研究的模式微生物,阐明微生物环境适应性及发挥有益功能等的分子机制。本文综述了近年来植物乳杆菌的生理功能和组学研究进展,以期为研究者提供借鉴。  相似文献