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121.
不同草莓品种的抑制栽培 总被引:1,自引:0,他引:1
选用6个草莓品种的大苗和小苗(大苗根茎>0.7 cm、三叶以上一心;小苗根茎≤0.7 cm、两叶一心)为材料,在0℃冷库中冷藏5个月后,分3批定植于大棚中(定植时间分别为7月30日、8月10日和8月20日),观测不同品种植株的成活率、营养生长状况、物候期、生理指标、果实营养品质及产量,结果表明:宝交早生大苗的成活率高达99.20%、营养生长状况好、物候期早、果实营养品质好、产量高,其单株产量比全明星小苗的高158.69%,为适宜的草莓抑制栽培品种;8月20日为草莓抑制栽培适宜的定植期;随着定植时间的推移,同一种草莓苗的根系活力、叶绿素含量逐渐增加,相对电导率、游离脯氨酸含量和丙二醛含量逐渐减少;每个品种均表现出大苗要优于小苗,大苗的产量比小苗的高72.09%~168.77%. 相似文献
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以中国知网统计的源期刊为依据,通过对1965年3月-2014年10月间有关相思研究论文的发表数量、发表时间、研究内容、发文单位、期刊分布等进行统计分析,了解我国相思研究进展,指出相思树研究的不足之处以及今后研究发展方向。 相似文献
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Effect of dietary daidzein on egg production, shell quality, and gene expression of ER-alpha, GH-R, and IGF-IR in shell glands of laying hens 总被引:1,自引:0,他引:1
Ni Y Zhu Q Zhou Z Grossmann R Chen J Zhao R 《Journal of agricultural and food chemistry》2007,55(17):6997-7001
Our previous studies demonstrated that dietary daidzein improves egg production in ducks during the late period of the laying cycle. The present study was aimed to investigate the effect of daidzein in laying hens, with more focus on eggshell quality. The expression of ER-alpha, GH-R, and IGF-IR mRNA in shell glands was determined to identify the target genes of daidzein action and to reveal the relationship between shell quality and profiles of gene expression in shell glands of laying hens. 1000 ISA hens, at 445 days of age, were allotted at random to two groups and given the basal diet with or without 10 mg of daidzein per kg diet for 9 weeks. Daidzein supplement significantly increased the egg laying rate and the feed conversion ratio. The eggshell thickness increased, while the percentage of cracked eggs decreased in daidzein-treated hens. Serum E2 and phosphate concentrations were not altered, but the level of serum Ca2+ and the tibia bone mineral density were significantly increased in the daidzein-treated group compared with their control counterparts. In parallel with the significant increase of oviduct weight, significant down-regulation of GH-R and IGF-IR mRNA and a trend of decrease in ERalpha mRNA expression in shell glands were observed in daidzein-treated hens. The results indicate that dietary daidzein improves egg laying performance and eggshell quality during the late (postpeak) laying stage of hens, which is associated with modulations in gene expression in the shell gland. 相似文献
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Ni Mhurchu C Blakely T Wall J Rodgers A Jiang Y Wilton J 《Public health nutrition》2007,10(6):608-615
OBJECTIVE: To pilot the design and methodology for a large randomised controlled trial (RCT) of two interventions to promote healthier food purchasing: culturally appropriate nutrition education and price discounts. DESIGN: A 12-week, single-blind, pilot RCT. Effects on food purchases were measured using individualised electronic shopping data ('Shop 'N Go' system). Partial data were also collected on food expenditure at other (non-supermarket) retail outlets. SETTING: A supermarket in Wellington, New Zealand. PARTICIPANTS: Eligible customers were those who were the main household shoppers, shopped mainly at the participating store, and were registered to use the Shop 'N Go system. Ninety-seven supermarket customers (72% women; age 40 +/- 9.6 years, mean +/- standard deviation) were randomised to one of four intervention groups: price discounts, nutrition education, a combination of price discounts and nutrition education, or control (no intervention). RESULTS: There was a 98% follow-up rate of participants, with 85% of all reported supermarket purchases being captured via the electronic data collection system. The pilot did, however, demonstrate difficulty recruiting Maori, Pacific and low-income shoppers using the electronic register and mail-out. CONCLUSIONS: This pilot study showed that electronic sales data capture is a viable way to measure effects of study interventions on food purchases in supermarkets, and points to the feasibility of conducting a large-scale RCT to evaluate the effectiveness of price discounts and nutrition education. Recruitment strategies will, however, need to be modified for the main trial in order to ensure inclusion of all ethnic and socio-economic groups. 相似文献
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The extract of the plant Rheum officinale Baill, mainly containing the anthraquinones physcion and chrysophanol, is highly active against plant powdery mildew. Experiments were conducted in the laboratory and greenhouse to determine the interaction of the two compounds on cucumber powdery mildew [Sphaerotheca fuliginea (Schlecht.) Poll] and on wheat powdery mildew [Blumeria graminis (DC.) Speer f. sp. tritici Marchal]. Physcion was much more bioactive than chrysophanol against these powdery mildews. There was a significant synergistic interaction between the two compounds on the diseases when the ratios of physcion to chrysophanol ranged from 1:9 to 5:5. The synergistic degree increased with increase in the chrysophanol proportion in the combination. The findings indicate that, in order to ensure constant efficacy of the extract on the disease, both the contents and the proportion of the main active ingredients physcion and chrysophanol have to be determined. 相似文献