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941.
Inter simple sequence repeat(ISSR) polymorphism was used to determine genetic diversity and phylogenetic relationships in 90 genotypes of wild and cultivated species of Oryza from different geographical regions of the world. In all the 17 primers used in ISSR-PCR, a total of 11 464 bands were amplified at 253 band positions/loci. The primer UBC-809 amplified the maximum bands(1 059) at 21 band positions. UBC-810 and UBC-835 amplified the minimum of 391 bands each at 7 and 14 band positions, respectively. The mean polymorphism information content ranged from 0.44 to 0.84 and resolving power ranged from 8.69 to 23.53. Un-weighted pair group method with arithmetic mean dendrogram and population structure based on the 17 primers separated all genotypes into 4 major clusters with a genetic similarity of 53%–100%. The first two clusters consisted of 30 O. rufipogon accessions each. In the third cluster, O. nivara and O. longistaminata grouped as one sub-cluster and all other O. nivara accessions and cultivars grouped as another sub-cluster. The fourth cluster had only five O. rufipogon accessions which can be a source of new genes. Four sub-populations were identified within O. rufipogon and two sub-populations within O. nivara at K = 7. A subset of six primers with high resolving power values were the most informative and grouped all genotypes almost similarly as the 17 primers did. Use of these six highly informative primers in ISSR-PCR is a cost effective and robust method for assessing genetic diversity in large germplasm collections of wild rice species. 相似文献
942.
Zheng J He J Ji B Li Y Zhang X 《Plant foods for human nutrition (Dordrecht, Netherlands)》2007,62(1):7-11
The root of Platycodon grandiflorum (Jacq.) A. DC has been reported to have a wide range of health benefits in oriental food. This study examined the hypoglycemic
effects of Platycodon grandiflorum (Jacq.) A. DC aqueous-ethanol extract (PGE) in streptozotocin (STZ) -induced diabetic ICR mice (STZ diabetic mice) for the
first time. The effects of PGE on blood glucose, plasma insulin levels and body weight were investigated. A significant decrease
in blood glucose levels was observed after single administration of PGE. Furthermore, Glibenclamide and PGE significantly
suppressed the rise in blood glucose after 30 min in the acute glucose tolerance test. Treatment with glibenclamide and PGE
resulted in a reduction in blood glucose levels from the 2nd week, and this reduction was maintained until the 4th week of
treatment. The body weight changed slightly in glibenclamide and PGE treated mice in comparison with the STZ control group.
Plasma insulin levels were increased with glibenclamide treatment in STZ diabetic mice, whereas such effect was not observed
with PGE. These results indicated that PGE could induce hypoglycemic effects without stimulating insulin secretion. 相似文献
943.
A series of field trials combining cultivars with different levels of resistance to Phythophtora infestans and different haulm killing methods was conducted in 1997, 1998 and 1999 to assess the contamination potential of the haulm.
In addition, the frequency of tubers with late blight was assessed after harvest and storage, combining effects of pretreatment
infection, infection by the haulm at harvest and the development of the disease during storage. Haulm killing was performed
by diquat (200, 400, 600 g a.i. ha-1), half cutting of the haulm in combination with diquat (100, 200, 300 g a.i. ha-1) or full cutting of the haulm. In those treatments where haulm killing was performed purely chemically the haulm remnants’
contamination potential tended to increase at reduced doses. Full mechanical destruction gave as low a contamination potential
as application of the full dose of chemical haulm killer. However, there were no consistent differences between the haulm
killing treatments in the frequency of blighted tubers after harvest and storage. This indicates that the input of chemical
haulm killers may be reduced. There was a large difference between years in tuber blight after harvest and storage, which
confirms that climatic factors are of major importance for tuber infection. The large difference found between the cultivars
in the frequency of tuber blight indicates that tuber resistance should be an important part of integrated late blight disease
management. 相似文献
944.
The effect of impact force when using inclined water jets on splittable bicomponents hydroentangled fabrics are investigated
focusing on changes in tensile properties and fiber splitting. The results indicated that with increase of impact force, the
tensile strength was increased in both machine direction (MD) and crosswise direction (CD). On changing of water jet inclination
angle, the tensile strength was the highest at 10 degree followed by 20 degree and the last 0 degree. The highest fiber splitting
were observed in pie segment (PA6/PET) followed by island in sea (PA6/COPET) fiber but no fiber splitting was observed for
island in sea (PET/COPET) fiber. The impact force in inclined mode of impact, played a great role in improving fiber splitting
and tensile properties of hydroentangled nonwoven fabrics. The Scanning Electron Microscope (SEM) photos were used for investigation
of fiber splitting by comparing fiber diameter before and after hydroentanglement. 相似文献
945.
为了解新麦草的种子产量及繁殖性状间的关系,对27份新麦草种质资源的单株种子产量与7个产量性状的关联性进行了分析。结果表明,新麦草的单株生殖枝数、穗轴节数、单穗小花数和千粒重与单株种子产量关联最密切,其相关性表现为单株生殖枝数>千粒重>穗轴节数>单穗小花数。经通径分析,单株生殖枝数(X1)对单株种子产量(Y)直接效应最大,其余依次是单穗小花数(X4)、单穗小穗数(X3)、千粒重(X7)、穗轴节数(X2)和单穗结实种子数(X5),其中单穗结实种子数和结实率对种子产量均表现为负效应,且未达到显著水平。经逐步回归分析得到回归方程Y= -9.880 2+0.27X1+0.012X4+2.011 1X7(R=0.805 8,P<0.001),说明提高单株生殖枝数、千粒重、单穗小花数对新麦草增产的贡献最大,增加结实率也可间接提高新麦草的单株种子产量。 相似文献
946.
Most multi-purpose water resources have been planned and constructed by governments in Taiwan to meet the water demands of
different users. However, economic and solvency differences among parties using water create conflicts regarding the reasonable
and equitable allocation of investment and operational costs. The Chi-Chi Weir in Nantou County, which was completed in 2002,
meets the high water demand of residents and the needs of industrial growth in central Taiwan. Thus, multi-purpose water reservoirs
are designed to serve agriculture, the public and industry. Three analytical methods, the quantity-based method, marginal
cost method, and separable cost remaining benefit method (SCRB), are employed to compare the cost allocation for different
parties using water. The quantity-based method indicates that proportional costs allocated to agriculture, the public, industry
and new irrigated areas are 88.02, 3.63, 7.86, and 0.49%, respectively. Via the marginal cost method, the proportional costs
allocated to agriculture, the public, hydropower, industry and new irrigated areas are 68.44, 2.51, 28.71, and 0.34%, respectively.
The marginal cost price of water is NT$ 2.97 ton−1; industrial use has the highest price. Based on the SCRB method, the proportional costs allocated to agriculture, the public,
hydropower, and new irrigated areas are 18.2, 22.2, 51.8, 4.8, and 2.9%, respectively. 相似文献
947.
Gymnema sylvestre is an important medicinal plant which bears bioactive compound namely gymnemic acids. The present work deals with optimization of cell suspension culture system of G. sylvestre for the production of biomass and gymnemic acid and we investigated effects of macro elements (NH4NO3, KNO3, CaCl2, MgSO4 and KH2PO4 - 0.0, 0.5, 1.0, 1.5 and 2.0× strength) and nitrogen source [NH4+/NO3− ratio of: 0.00/18.80, 7.19/18.80, 14.38/18.80, 21.57/18.80, 28.75/18.80, 14.38/0.00, 14.38/9.40, 14.38/18.80, 14.38/28.20 and 14.38/37.60 (mM)] of Murashige and Skoog medium on accumulation of biomass and gymnemic acid content. The highest accumulation of biomass (165.00 g l−1 FW and 15.42 g l−1 DW) was recorded in the medium with 0.5× concentration of NH4NO3 and the highest production of gymnemic acid content was recorded in the medium with 2.0× KH2PO4 (11.32 mg g−1 DW). The NH4+/NO3− ratio also influenced cell growth and gymnemic acid production; both parameters were greater when the NO3− concentration was higher than that of NH4+. Maximum biomass growth (159.72 g l−1 of FW and 14.95 g l−1 of DW) was achieved at an NH4+/NO3− ratio of 7.19/18.80, and gymnemic acid production was also greatest at the same concentration of NH4+/NO3− ratio (11.35 mg g−1 DW). 相似文献
948.
Krzysztof Dziedzic Danuta Górecka Artur Szwengiel Hanna Sulewska Ivan Kreft Elżbieta Gujska Jarosław Walkowiak 《Plant foods for human nutrition (Dordrecht, Netherlands)》2018,73(1):82-88
In this report, we presented the profile of polyphenolic substances in flowers, leaves, stalk and roots of Fagopyrum tataricum estimated by using RP–UHPLC–ESI-MS equipment (reversed-phase ultra-high-performance liquid chromatography electrospray ionisation mass spectrometry). The neutral detergent fibre, acid detergent fibre, acid detergent lignin, cellulose and hemicellulose were also determined. Flowers, leaves, stalk and roots showed varying levels of dietary fibre and polyphenols. The highest content of neutral and acid detergent fibre were found in the roots (63.92 and 45.45% d.m., respectively) while the most rich in phenolic compounds were flowers (4.8 mg/1 g d.m.). Root and stalk contained the highest level of cellulose, 38.70 and 25.57% d.m., respectively. Among the investigated polyphenolic substances such as: 2,6-dihydroxybenzoic acid, 3,4-dihydroxybenzoic acid, 3,5-dihydroxybenzoic acid, 4-hydrobenzoic acid, caffeic acid, catechin, chlorogenic acid, fagopyrin, ferulic acid, myricetin, gallic acid, isovanilic acid, isovitexin, kaempferol, luteolin, p-coumaric acid, procyanidin B2, quercetin, quercetin 3-D galactoside, rutin, syringic acid and vitexin, we observed that the contents of rutin and chlorogenic acid were the highest. We found some correlation between dietary fibre fractions and individual phenolic substances. The levels of acid detergent fibre (ADF), cellulose and hemicellulose were negatively correlated with isovitexin, kaempferol, vitexin, fagopyrin, caffeic acid and procyanidin B2 content. In this investigation, two solvents (water and methanol) were estimated regarding their extraction efficiency of phenolic compounds. Taking these results into consideration, we recommend using methanol as the extractor to isolate chlorogenic acid, fagopyrin, kaempferol, procyanidin B2, quercetin, quercetin 3-D-galactoside, rutin, vitexin, and water for other investigated polyphenolic substances obtained from Fagopyrum tataricum. 相似文献
949.
Luciana Linhares de Azevedo Bittencourt Kelly Alencar Silva Valéria Pereira de Sousa Gizele Cardoso Fontes-Sant’Ana Maria Helena Rocha-Leão 《Plant foods for human nutrition (Dordrecht, Netherlands)》2018,73(4):278-286
In the processing of fruits such as blueberry (Vaccinium sp), that has high levels of phenolic acid, the food industry produces tons of organic waste that causes harm to the environment. Encapsulation is a technique used to take advantage of these wastes. Several methods are used to encapsulate substances, among them ionotropic gelation proves to be a simple, precise, efficient and economical method for obtaining particles with encapsulated bioactives. In this manner, the aim of this study was to test sodium alginate as wall material to encapsulate blueberry residue by ionotropic gelation. The microbeads were characterized by scanning electron microscopy (SEM), x-ray diffraction (XRD), total phenolic compounds, antioxidant capacity and in vitro dissolution. The results showed that the microbeads had surface invagination; retention of 67.01% of the phenolic compounds after encapsulation and 68.2%, phenolic release 120 min after in vitro dissolution. The results suggest that the tested matrix was suitable for encapsulation. The produced microbeads are promising for applications in food products, once the phenolic compounds present in the blueberry residues were maintained after encapsulation. 相似文献
950.
Mana Mashkour Yahya Maghsoudlou Mahdi Kashaninejad Mehran Aalami 《Potato Research》2018,61(4):375-389
In this study, the effect of a vacuum impregnation (VI) process with pulsed electric field (PEF) pretreatment on fortification of whole potato with ferric pyrophosphate was investigated. The VI process and PEF pretreatment were optimized with respect to physicochemical attributes of PEF-VI-processed samples using response surface methodology (RSM). The results indicated that the iron content of VI-processed and PEF-VI-processed potatoes was increased about 126 and 457%, respectively, compared to unprocessed potatoes. A more intensive PEF pretreatment led to a higher cell disintegration, decrease in colour and textural parameters and also increase in components leakage from treated potato. Our study suggests that whole 180-g potatoes should be pretreated at 394 V/cm with 36 pulses and then treated at 3.5 kPa for 37 min in vacuum stage and 39 min restoration time in atmospheric stage to achieve the highest iron fortification and the lowest physicochemical changes during PEF-VI processing. 相似文献