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91.
[目的]开展海南梧桐种子萌发及插条扦插繁殖试验,为海南梧桐繁殖体系构建及其开发利用提供参考依据.[方法]采用完全随机试验设计,以物理破损(去除种皮1/5和划破种皮)和化学激素(NAA、GA3溶液)浸泡处理海南梧桐种子,分析其种子萌发效果;并通过扦插试验,研究扦插基质(砂、砂+椰糠、园土)、生根粉(ABT:0、1000.00、1500.00 mg/L)及捅条穗龄(当年生、1~2年生、3~4年生)对海南梧桐枝条扦插成活率的影响.[结果]物理破损及化学激素浸泡法处理均可提高海南梧桐种子发芽率,其中物理破损处理的海南梧桐种子发芽率达90.60%~91.70%,显著高于其他处理(P<0.05,下同).扦插试验结果表明,影响海南梧桐扦捅成活率的3个因素(扦插基质、ABT质量浓度、插条穗龄),其主效应极显著(P<0.01);在二维互作中,基质×ABT互作效应显著,基质×插条穗龄、ABT×捅条穗龄互作效应不显著(P>0.05,下同);在三维互作基质×ABT×捕条穗龄中,交互效应不显著.各因素对海南梧桐扦插成活率影响的排序为插条穗龄(F=21.85)>ABT质量浓度(F=11.05)>基质种类(F=9.45)>基质×ABT(F=2.85).最适扦插组合为:砂+ABT(1500.00 mg/L)+1~2年生插条,扦插成活率达20.00%.[结论]对海南梧桐种子进行物理破损或激素浸泡软化处理均可促进其萌发;1~2年生枝条经1500.00 mg/L ABT浸泡12h扦插于砂基质中最有利于其生根成活. 相似文献
92.
Wrieden WL Anderson AS Longbottom PJ Valentine K Stead M Caraher M Lang T Gray B Dowler E 《Public health nutrition》2007,10(2):203-211
OBJECTIVE: To evaluate the feasibility of undertaking a food skills intervention study in areas of social deprivation aimed at altering cooking confidence, food preparation methods and dietary choices. DESIGN: A standardised skills programme was implemented in community-based settings. Pre- (T1) and post-intervention (T2) and 6-month follow-up (T3) measures (7-day diaries and self-administered questionnaires) were undertaken in intervention and comparison groups. SETTING: Eight urban communities in Scotland. SUBJECTS: One hundred and thirteen adults living in areas of social deprivation. RESULTS: It was clear that many subjects led fragmented lives and found commitment to intervention classes problematic. Sixty-three subjects completed the final (T3) assessments. The response to each component varied due to inability to attend sessions, illness, study requirements, employment, moving out of the area, change in circumstances, loss of interest and loss of postal questionnaires. At baseline, reported consumption of fruit and vegetables was low (mean frequency 8.1 +/- 4.78 times per week). Fruit intake increased significantly (P < 0.05) between T1 and T2 in the intervention group (1.7 +/- 2.36 to 2.7 +/- 3.28 times per week) only. Between T1 and T3, there was a significant increase (P < 0.05) in intervention subjects who reported confidence in following a recipe (67-90%,). CONCLUSIONS: This exploratory trial shows that a food skills intervention is likely to have a small but positive effect on food choice and confidence in food preparation. A full-scale randomised controlled trial in this hard-to-reach group would require a range of flexible approaches rather than a fully defined intervention, and presents challenges for trial design. 相似文献
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非公有制林业主体融资问题的思考 总被引:4,自引:0,他引:4
针对不同层次的个体林业,设计了民间融资、"报账制"式银行信贷等方式以求解决个体林农融资困难问题. 相似文献
95.
László Egyed Anna Nagy András Lakos Viktor Zöldi Zsolt Lang 《Zoonoses and public health》2023,70(1):81-92
The authors analysed epidemiological data of the Hungarian tick-borne encephalitis epidemic from the past seven decades. A total of 911 meningitis serosa cases were described from 1930-1950 s by local hospital physicians, indicating that the virus had been present in the country decades before its official identification in 1952. The virus spread freely in the 1950s–1960s, occupying almost all habitats where ticks occurred in large numbers. The increasing number of cases drove authorities to classify this illness as a notifiable disease in 1977 and to organize the first measures to stop the epidemic. Statistical analysis revealed that the large-scale vaccination launched from the 1990s was responsible for the sharp decrease in the number of human cases from 1997. A significant negative correlation was found between the number of vaccine doses sold and human cases 6 years later. The TBEV endemic area covers 16.57% of the territory and 16.65% of the population of the country. In the last 10 years, 186,000 vaccine doses/year in average were enough to keep the incidence of human TBEV infections between 0.45 and 0.06/100,000 persons. A 20-year-long study found evidence for easing clinical signs in TBEV-infected hospitalized patients. Statistics found a sharp decrease in the number of samples sent for TBEV diagnosis after 1989. Male dominance of patients was characteristic of the epidemics since the 1940s, but now analysis of detailed data from the 1981–2021 period (60.5%–87.5%) proved the statistical significance of this dominance. Obviously, the voluntary vaccination programme was the tool which broke the spread of the epidemic. Widespread public awareness of the disease and the tick vector, probable evolutionary spread of less pathogenic virus strains supplemented with the vaccination campaign led to a negligible level of human TBE cases in Hungary in the last years. 相似文献
96.
为了明确油菜菌核病生防菌盾壳霉施用后对土壤微生物群落结构的影响,为盾壳霉在实际生产中的应用提供理论依据。以喷施盾壳霉为处理组(CM),喷施清水为对照组(CK),调查不同处理下油菜菌核病的发生情况,并采用高通量测序技术分析土壤微生物群落变化。结果表明:对照组油菜菌核病的病株率和病情指数分别高达74.64%和46.13;而处理组菌核病病株率和病情指数分别降低至23.33%和9.37,防治效果达79.70%;此外,喷施盾壳霉还改变了油菜根际土壤微生物群落结构,使得土壤真菌种群的丰富度和多样性程度显著增加;在门水平上,喷施盾壳霉促使土壤中变形菌门、芽单胞菌门、子囊菌门、被孢霉门和担子菌门等的相对丰度增加,导致放线菌门的相对丰度比例降低。在属水平上,施加盾壳霉可增加鞘氨醇单胞菌属、溶杆菌属、独岛菌属、短梗蠕孢属、镰刀菌属、曲霉属、Plectosphaerella等属的丰富度,会显著降低unidentified_Chitinophagaceae、寡养单胞菌、地杆菌属、梭孢壳属和Cutaneotrichosporon等的相对丰度。喷施盾壳霉能有效防治油菜菌核病,增加土壤真菌种群丰富和多样性,改善土壤微生物群落结构,研究结果为盾壳霉的田间大面积推广提供依据。 相似文献
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100.
陈新独创"旺根技术"能促使植物根系发达,移栽田间后保持强盛生长力,提前投产。测定儋州基地旺根技术培育的沉香、花梨木和斯里兰卡橄榄苗木的树高和地径等指标,结果表明,移栽1.5年的沉香和花梨木的平均地径分别达到(5.84±1.43)cm和(4.04±0.64)cm;而移栽2.5年的沉香、花梨木和斯里兰卡橄榄,平均地径分别为(12.10±1.89)cm,(9.37±1.05)cm和(15.26±3.18)cm,均已开花结果,且硕果累累。此外,旺根植物间隔3个月的平均地径增大明显,沉香为1.0 cm,花梨木为0.7 cm,斯里兰卡橄榄为1.44 cm,比传统苗木的生长速度提升数倍。该技术为作物超高产研究提供栽培依据。 相似文献