Effects of Variations in Starch Synthase on Starch Properties and Eating Quality of Rice

Abstract

We evaluated the effects of functional variation in three starch synthases in rice (Oryza sativa L.)?granule-bound starch synthase I (GBSSI, wx), starch synthase I (SSI, SSI), and starch synthase IIa (SSIIa, alk)?between indica cultivar Kasalath and japonica cultivar Nipponbare on starch properties and eating quality. We used three near-isogenic lines?NIL(Wx^a), NIL(SSI ^k), and NIL(Alk)?containing chromosomal segments of Kasalath on a Nipponbare genetic background. The Wx^a allele explained most of the difference in amylose content between the two cultivars, and decreased the peak viscosity and breakdown to less than half of those of Nipponbare. These changes reduced the quality of cooked rice both just after cooking and after storage at 5ºC. The variation in SSIIa also affected the eating quality after storage of cooked rice at 5ºC : NIL(Alk) became harder and less sticky than Nipponbare, although the rices were comparable just after cooking. Differential scanning calorimetry revealed faster retrogradation of the once-gelatinized starch in NIL(Alk). The variation in SSI alleles hardly affected these properties.     

The Chemistry and Agronomic Effectiveness of Phosphate Fertilizers

Summary

Plants take up P from soil solution, so water-soluble P fertilizers are generally more effective than poorly soluble forms. The original sources of P used for agriculture were poorly soluble materials, including manures, bones, guano and phosphate rock. In contrast, highly soluble monocalcium phosphate, monoammonium phosphate and diammonium phosphate are the major compounds present in modern, manufactured solid fertilizers containing water-soluble P. This paper describes how the water-soluble P fertilizers are made, the dissolution of P in the granules of the fertilizers, the reactions of the fertilizer solution with the soil as P moves out of the granule into the soil, the agronomic effectiveness of the fertilizer in the year of application, and in the years after application (residual value).     

Reduction of Phosphatic and Potash Fertilizer in Sweet Corn Production by Pre-transplanting Application of Potassium Phosphate to Plug Seedlings

Abstract

To develop a new fertilizing system with a reduced amount of phosphatic fertilizer in sweet corn production, we applied potassium phosphate to the plug seedlings before transplanting to the field, and examined its effects on growth, yield, photosynthetic activity and absorption of minerals. The amount of phosphatic and potash fertilizers necessary to grow sweet corn could be reduced by the pre-transplanting KP application (PTKPA) to the plug seedlings. We considered the mechanisms involved in the reduction of P and K application rate by PTKPA as follows; 1) PTKPA increased the P content of plant, which accelerated the root establishment. 2) The advanced root establishment not only reduced the duration of water stress, but also increased absorption of the essential nutrients such as N and Mg. 3) Higher content of N and Mg led to higher chlorophyll content and possibly protein content, which activated photosynthesis during the early growth stage. 4) Improved photosynthetic activities increased NAR during the early growth stage. 5) This increase in NAR accelerated leaf expansion, increasing LAI. 6) Larger LAI during the early growth stage led to larger LAI throughout the growing stage, resulting in a higher CGR and ear yield.     

Bone Regeneration of Rat Tibial Defect by Zinc-Tricalcium Phosphate (Zn-TCP) Synthesized from Porous Foraminifera Carbonate Macrospheres

Foraminifera carbonate exoskeleton was hydrothermally converted to biocompatible and biodegradable zinc-tricalcium phosphate (Zn-TCP) as an alternative biomimetic material for bone fracture repair. Zn-TCP samples implanted in a rat tibial defect model for eight weeks were compared with unfilled defect and beta-tricalcium phosphate showing accelerated bone regeneration compared with the control groups, with statistically significant bone mineral density and bone mineral content growth. CT images of the defect showed restoration of cancellous bone in Zn-TCP and only minimal growth in control group. Histological slices reveal bone in-growth within the pores and porous chamber of the material detailing good bone-material integration with the presence of blood vessels. These results exhibit the future potential of biomimetic Zn-TCP as bone grafts for bone fracture repair.     

Long term nitrogen and phosphorus application to veld

Abstract

The long term effects of a 5N x 3P factorial fertilizer application trial on hay yields, botanical composition and soil properties of veld are presented. Significant increases in hay yields were recorded during most years. There was a strong correlation (r = 0,757) between mean (over all 15 treatment combinations) annual hay yields and annual rainfall.

N and N + P fertilizer lowered the percentage basal cover of the tribe Andropogoneae. A notable exception of this tribe was Heteropogon contortus which increased significantly at the lower fertilizer levels. The basal cover of the tribe Paniceae generally increased with N and P fertilizer application. The reaction of the basal cover of the tribe Eragrosteae showed little by way of definite tendencies.

Increasing N and P levels generally resulted in decreases in soil pH, Ca, Mg, K and an increase in compaction of the soil surface layer. However, higher levels of N x P resulted in higher water infiltration rates than occurred in control plots, although initial infiltration rates were greatest in control plots. Despite certain undesirable effects of fertilizers on basal cover and certain chemical and physical properties of the soil, the fertilized plots maintained a high level of production.     

中国荷斯坦牛FASN基因部分序列PCR-SSCP多态性与泌乳性状的相关性

【目的】研究奶牛脂肪酸合成酶(Fatty acid synthase,FASN)基因多态性对产奶量和乳成分的影响,为中国荷斯坦牛的优化育种提供相应的分子遗传学依据。【方法】以464头中国荷斯坦牛为研究材料,参照奶牛生产性能测定(Dairy herd improvement,DHI)方法采集产奶量和乳成分数据;采集试验牛血样,提取DNA,PCR扩增FASN基因,用单链构象多态性(Single-strand conformation polymorphism,SSCP)技术并结合测序确定基因型;用最小二乘法进行基因多态性与泌乳性状的关联性分析。【结果】FASN基因外显子34存在2个等位基因、2种基因型,A、B等位基因频率分别为0.813 9和0.186 1,试验群体在这一位点上极显著偏离Hardy-Weinberg平衡状态(P<0.01),遗传杂合度(He)和多态信息含量(PIC)分别为0.372 3和0.257 0。测序结果显示,与普通黄牛FASN基因序列(GenBank登录号:AF285607)相比,B等位基因在第16 024和16 039位核苷酸处分别发生了A→G和C→T碱基突变,其中A→G突变导致苏氨酸变成丙氨酸,C→T突变导致精氨酸变为色氨酸;A等位基因与AF285607序列相同。最小二乘法分析表明,AA型个体305d乳脂量显著高于AB型个体(P<0.05),等位基因A为高乳脂量优势基因。【结论】FASN基因外显子34突变位点可作为高乳脂的分子遗传标记应用于中国荷斯坦牛的标记辅助选择育种中。     

Effect of N-acetyl-L-cystein on blood pressure and endothelial function in aorta of rats exposed to chronic intermittent hypoxia

AIM: To investigate the effect of N-acetyl-L-cystein (NAC) on blood pressure and endothelial function in the aorta of the rats exposed to chronic intermittent hypoxia (CIH). METHODS: Thirty healthy male SD rats were randomly divided into 3 groups: control group, CIH group and CIH+NAC group. The systolic blood pressure (SBP) was measured with tail-cuff me-thod. Real-time fluorescence quantitative polymerase chain reaction (qRT-PCR) was used to detect the mRNA expression of endothelial nitric oxide synthase (eNOS） and endothelin-1 (ET-1) in the thoracic aorta. The protein expression of eNOS in the thoracic aorta was examined by Western blotting. The levels of ET-1 in the thoracic aorta and serum were detected by radioimmunoassay. The serum nitric oxide was determined by nitric acid reduction method.The superoxide dismutase (SOD) activity in peripheral blood plasma was detected by xanthine oxidase method.The serum malondialdehyde content was detected by thiobarbituric acid method, and superoxide anion (O-·2) in thoracic aorta was determined by chemical colorimetric method. RESULTS: Compared with the control animals, CIH exposure was associated with decreased SOD level, and NAC-treated CIH animals showed recovery in SOD level. NAC treatment prevented CIH-induced hypertension as well as CIH-induced increase in MDA. The aorta eNOS mRNA and protein, and serum NO levels in CIH group were lower than those in control group, and those in NAC treatment group were higher than those in CIH group. The increases in ET-1 mRNA,ET-1 protein and O-·2 levels in the aorta, and the elevated circulating ET-1 level were also observed in CIH-exposed animals. Treatment with NAC significantly decreased the mRNA and protein levels of ET-1, the O-·2 content, and the circulating ET-1 level in CIH-exposed animals. CONCLUSION: NAC protects endothelial function and alleviates hypertension by suppressing the oxidant stress in the aorta tissues, indicating that oxidant stress may be involved in the mechanism of endothelial disorder of CIH-induced hypertension.     

Effect of Sini decoction on expression of caveolin-1 and eNOS in EAhy926 cells injured by homocysteine

AIM：To investigate the mechanism of Sini decoction in treating human vascular endothelial cell injury and the roles of caveolin-1 and nitric oxide (NO) system in this procedure. METHODS：Model of human umbilical vein endothelial EAhy926 cells injured by homocysteine (Hcy) was established. The protective effect of Sini decoction on the injured EAhy926 cells was observed, and the expression of caveolin-1 and endothelial nitric oxide synthase (eNOS) was detected by real-time fluorescence quantitative PCR and Western blotting. RESULTS：Compared with control group, the Hcy-treated EAhy926 cells showed reduced adherent cell number and NO concentration in culture supernatant, decreased expression of eNOS mRNA and protein, and increased expression of caveolin-1 mRNA and protein (all P<0.05). Compared with Hcy group, better growth of adherent cells, elevated NO concentration in culture supernatant, attenuated expression of caveolin-1 mRNA and protein, and enhanced expression of eNOS mRNA and protein in Sini decoction groups were observed (all P<0.05). CONCLUSION：Homocysteine may injure EAhy926 cells by enhancing the expression of caveolin-1 and suppressing the expression of eNOS, while Sini decoction may protect EAhy926 cells by suppressing the expression of caveolin-1 and enhancing the expression of eNOS.     

麦田抗性生物型荠菜对苯磺隆的抗性机制研究

为明确抗性生物型荠菜对苯磺隆的抗性机制,分别测定了苯磺隆对抗性和敏感生物型荠菜体内乙酰乳酸合成酶(ALS)、谷胱甘肽-S-转移酶(GSTs)、超氧化物歧化酶(SOD)、过氧化物酶(POD)和过氧化氢酶(CAT)的影响。结果表明:离体条件下,抗性生物型荠菜体内ALS对苯磺隆的敏感性明显降低,苯磺隆对荠菜抗性和敏感生物型ALS的抑制中浓度(I50)分别为0.722 8和0.052 1 μmol/L,抗性与敏感生物型I50的比值为13.87;活体条件下,施用苯磺隆后,抗性和敏感生物型荠菜ALS活性均受到一定程度的抑制,但抗性生物型ALS活性受到抑制后能逐渐恢复,而敏感生物型则不能恢复;经苯磺隆处理后,抗性生物型GSTs相对活力明显高于敏感生物型,而抗性和敏感生物型体内POD、SOD和CAT相对活力无明显差异。研究表明,抗性生物型荠菜体内ALS对苯磺隆敏感性降低是其抗药性产生的原因之一,而GSTs对苯磺隆代谢能力的差异也可能与荠菜对苯磺隆的抗性有关。     

Analysis of Phosphate Rock Dissolution Determining Factors Using Principal Component Analysis in Some Acid Indonesian Soils

Abstract

Dissolution of phosphate rock (PR) materials and its subsequent phosphorus (P) availability to plants depend upon soil characteristics, PR characteristics, type of crops, and environmental conditions. Agronomic effectiveness of the PR sources has frequently been investigated in the field or in the greenhouse. This is time consuming and not cost‐effective. Therefore, identification of the soil characteristics influencing the dissolution of PR is very important for direct application of P sources. The principal component analysis was used to summarize the characteristics of acid soils in an incubation system into a number of factors that may affect PR dissolution. Three major factors were selected in this study: 1) soil texture, 2) soil acidity, and 3) fertilization. Using the scores of the individual factors as independent variables, a stepwise regression analysis was performed to derive a PR dissolution function. The coefficient of determination (R²) reached 0.91**, and the magnitude of the different factors affect PR dissolution following the order of soil texture (54%)>soil acidity (43%)>fertilizer (3%). Fertilizer was not significant as a PR dissolution factor.