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排序方式: 共有909条查询结果,搜索用时 375 毫秒
61.
Amer Ibrahim Basha Stefano Padulosi Kamel Chabane Adnan Hadj-Hassan Ehsan Dulloo Mario Augusto Pagnotta Enrico Porceddu 《Genetic Resources and Crop Evolution》2007,54(8):1807-1816
Pistachio (Pistacia vera L.) is a strategic nut tree species in the Middle East which holds comparative advantage over other fruit trees in view of
its hardiness, income generation opportunities and benefits for the ecosystem. Yet pistachio cultivation depends on a very
narrow genetic base, in spite of the existence of many varieties still marginally exploited. Syria is an important center
of diversity for pistachio. A country wide ecogeographic survey in this country was carried out to determine the extent of
pistachio genetic diversity and its use. As a whole, 114 accessions were collected from 37 farms to assess diversity at morphological
and molecular level. Molecular evaluation was carried out using Amplified Fragment Length Polymorphism (AFLP) technique and
performed using seven primer pair combinations. Results from the studies allowed the identification of 25 pistachio female
varieties in Syria, some of which unique and described for the first time. Three groups of pistachio diversity were identified
by cluster analysis which provides useful information about the distribution of genetic diversity in Syria for enhanced use
and sustainable conservation. 相似文献
62.
Li CP Salvador AS Ibrahim HR Sugimoto Y Aoki T 《Journal of agricultural and food chemistry》2003,51(23):6808-6815
Food proteins were phosphorylated by heating in a dry state in the presence of phosphate. When casein, whey protein isolate (WPI), and egg white proteins (EWP), which were lyophilized from their solutions in a phosphate buffer, were dry-heated at various temperatures and pH levels for 1-5 days, EWP was more highly phosphorylated than casein and WPI. Phosphorylation of EWP was promoted with a decrease of pH from 7.0 to 3.0 when the incubation temperature was raised from 55 to 100 degrees C. The phosphorus content of EWP increased from 0.08 to 0.64% by dry-heating at pH 3.0 and 85 degrees C for 5 days in the presence of phosphate. The electrophoretic mobility of EWP increased with an increase in the phosphorylation level. The heat-induced polymerization of EWP by dry-heating was not affected by the presence of phosphate. Although the solubility of EWP decreased by dry-heating at pH 3.0-5.5, the phosphorylation depressed the insolubilization at low pH. The phosphate bonds in phosphorylated EWP (P-EWP) were stable at pH 2.0-10.0 and were more acid-labile and base-stable than phosphoesters of egg riboflavin-binding protein (RfBP). (31)P NMR spectral data suggested that besides phosphoesters, phosphodiester and polyphosphate bonds were introduced in P-EWP. Heat stability of EWP was improved, and calcium phosphate-solubilizing ability of EWP was enhanced by phosphorylation. 相似文献
63.
“三定”栽培对双季超级稻养分吸收积累及氮肥利用率的影响 总被引:2,自引:0,他引:2
为探讨南方双季超级稻对氮、磷、钾养分的吸收积累及利用规律,于2008—2010年在湖南长沙和浏阳以超级早稻陆两优996、陵两优268和超级晚稻丰源优299、天优华占为材料进行大田定位试验,比较了“三定”栽培、免耕摆栽和传统栽培条件下双季超级稻不同生育期植株体内氮、磷、钾吸收积累特点及氮肥利用率。与传统栽培相比,“三定”栽培双季超级稻生长前期(分蘖中期)氮、磷、钾的吸收量较低,幼穗分化期差异甚小,而齐穗期(早季平均为10.71、2.23和11.82 g m-2,晚季平均为12.25、2.69和16.37 g m-2)和成熟期(早季平均为13.61、3.01和13.71 g m-2,晚季平均为17.16、3.31和18.31 g m-2)较高;氮肥的偏生产力(平均为53.40 kg kg-1)、吸收利用率(平均为55.98%)、农学利用率(平均为22.27 kg kg-1)较高,分别提高29.00%、88.92%和46.67%。免耕摆栽双季超级稻不同生育时期氮、磷、钾的吸收特点与“三定”栽培相似,但其氮肥的偏生产力、吸收利用率和农学利用率(平均为50.24 kg kg-1、52.75%、19.33 kg kg-1)分别比“三定”栽培降低6.29%、6.12%和15.19%。由此可见,双季超级稻生产采用“三定”栽培技术有利于提高氮肥利用率。 相似文献
64.
为探讨南方双季稻区超级稻高产栽培技术,于2008—2010年在湖南长沙和浏阳以超级早稻陆两优996、陵两优268和超级晚稻天优华占、丰源优299为材料进行大田定位试验,比较了“三定”栽培、免耕摆栽和传统栽培下双季超级稻的产量形成特点和生理特性。与传统栽培相比,“三定”栽培齐穗期的颖花伤流量、根系氧化力、根冠比、叶面积指数及籽粒结实期剑叶的光合速率较高,齐穗后剑叶SPAD值下降缓慢、干物质积累量大,有效穗数和每穗粒数多,早季平均产量为7.18 t hm-2,增产11.68%,晚季平均产量为8.39 t hm-2,增产7.41%;免耕摆栽干物质积累量大、有效穗数多,但其收获指数、每穗粒数和结实率居劣势,使其单季增产效果不显著。由此可见,南方双季超级稻在“三定”栽培下后期生理优势明显,产量构成因子协调,增产效果显著。 相似文献
65.
66.
Fig has been a typical fruit component of the health-promoting Mediterranean diet for a very long time. Phytochemical characters and antioxidant capacity of green-, yellow-, brown-, purple-, and black-fruited fig (Ficus carica L.) accessions were investigated. In this study, total phenolics (TP), total anthocyanins (TA), fructose (FRUC), glucose (GLUC), sucrose (SUC), and variables (such as L*, a*, C*, and hue°) describing fruit skin colors were examined. Also, the antioxidant capacity (TAC) of fig fruits was determined by the ferric reducing antioxidant power (FRAP) assay. Antioxidant capacity was significantly correlated with the polyphenol and anthocyanin (r = 0.74 and 0.63, respectively) contents of fruits. Black fig accessions had the highest TAC (range of 7.9–16.1, mean 12.4 Fe2+ mmol/kg FW), TA (range of 32.3–356.0, mean 128.4 μg cy-3-rutinoside/g FW), and TP content (range of 69.1–220.0, mean 118.9 mg GAE/100 g FW). These black-fruited accessions had 2-fold greater TAC, 15-fold greater TA, and 2.5-fold greater TP than green and yellow fig accessions. However, the FRUC, GLUC, and SUC content of brown and purple fig accessions were higher than those of other color groups. The predominant sugars present were fructose (∼56%) and glucose (∼43%), as determined by HPLC. 相似文献
67.
The aim of this investigation is to compare the physicochemical properties and chemical composition of Phoenix canariensis seed oil at different stages of seed date ripening. It was demonstrated that the saponification number of the oil increases during the maturation from 179.24 to 191.28 (mg KOH/g of oil), whereas the seed oil yield, the iodine number, the p-anisidine value, the peroxide value, the acidity and the unsaponifiable matter decrease from 14.73% to 10.36%, from 89.37 to 76.66 (g/100 g of oil), from 5.51 to 3.67, from 17.66 to 3.62 (mequiv. O2/kg of oil), from 1.49% to 0.59% and from 2.72% to 1.77%, respectively. The tocol content increases as the maturity advanced. The percentages of sterols show continuous changes during ripening. The saturated fatty acid content increases throughout the ripening process. The oleic fatty acid content decreases during the seeds maturation, but increases at the end, whereas linoleic acid content initially shows an increase, and then a decrease. The total phosphorus content decreases during the period of ripening. The three samples of the seed oil show a high kinetic stability during the heating and cooling, as characterised by the differential scanning calorimetry (DSC). The DSC curves reveal an increase in the melting point from −7.73 °C to 3.71 °C but the melting enthalpy remains the same, 62.06 J/g, during the ripening of the dates. 相似文献
68.
The efficacy of 30% aqueous urea solution, borax powder and spore suspensions of Phlebiopsis gigantea and Trichoderma harzianum against establishment of artificially inoculated Heterobasidion abietinum on Abies cilicica was tested both in the field and in a simulated stump treatment experiment carried out in a growth chamber. In the field, in each of the four selected stands 20 fresh stumps per control agent were treated and 20 stumps were left as untreated controls. In two of the stands, the treatments were applied in June and in the two others in November. Stumps were sampled twice, at 6‐ and 12‐months after treatment. In the growth chamber, 10 log pieces per treatment and control were used, and sampling performed after 6‐week incubation. Results of the urea and borax treatments were consistent between the experiments; the mean efficacies were 98.8 and 99.4% in the growth chamber, and 80.2–91.3 and 89.4–90.1% in the two samplings of the field experiment, respectively. Despite the high efficacies of the P. gigantea (85.9%) and T. harzianum (97.5%) treatments in the growth chamber, efficacies of these biological control agents in the field were 47.1–49.2 and 61.3–65.5%, respectively. 相似文献
69.
Alate viviparous females of Wahlgreniella nervata (Gillette) were found on a Damask rose (Rosa damascena Mill.) plantation in Isparta Province, Turkey. The aphid is recorded for the first time from Turkey. Besides, Damask rose
is a new host for this species. Brief information about this aphid including a key to the alate females of aphid species known
to infest Damask rose in Turkey is provided. 相似文献
70.