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51.
摘 要:为有效控制玉米地下害虫、蚜虫和茎基腐病的常年危害,筛选具有较好控制作用的种衣剂,笔者开展了14种悬浮种衣剂田间药效试验。试验表明:14种种衣剂对供试玉米品种出苗安全;氟虫腈?噻虫嗪(30%悬浮种衣剂)(1:1000)处理的出苗率96.7%为最高值。氟虫腈?噻虫嗪(30%悬浮种衣剂)(1:1000)对玉米地下害虫、玉米蚜虫的防治效果分别达84.8%、80.0%。精甲?咯?嘧菌(11%悬浮种衣剂)(1:2000)对玉米茎基腐病的防治效果达73.7%。说明以噻虫嗪、氟虫腈和甲霜灵为主的复配防治玉米地下害虫、蚜虫、茎基腐病,能够取得较好的防治效果。建议针对不同的生态类型区域,结合品种、施肥、管理等措施选用不同的配方,以取得最佳的防治效果。 相似文献
52.
氯化钙处理对菠萝黑腐病的防控效果及机制分析 总被引:1,自引:0,他引:1
为了降低采后菠萝果实由黑腐病引起的腐烂损失,本文研究了氯化钙处理对黑腐病的防控效果及相关机制。结果表明,1%氯化钙处理对菠萝黑腐病有最好的抑制作用和防治效果。1%氯化钙处理对病菌菌丝生长影响不大,但可明显抑制病原菌的产孢;氯化钙处理明显降低发病果实中多聚半乳糖醛酸甲酯酶(PMG)、纤维素酶(CX)和β-葡萄糖苷酶(CB)的活性,但对多聚半乳糖醛酸酶(PG)活性变化没有明显影响;氯化钙处理明显提高贮藏中后期菠萝果实中过氧化氢(H2O2)的含量,明显提高抗病相关酶苯丙氨酸解氨酶(PAL)、多酚氧化酶(PPO)、几丁质酶(CHI)和β-1,3-葡聚糖酶(GLU)的活性。说明氯化钙处理对黑腐病有较好的防控效果,一方面是由于其降低了病原菌的致病性,另一方面是诱导菠萝果实提高了抗病性。因此,适宜浓度的氯化钙处理为菠萝采后黑腐病的绿色防控提供了一条新的途径。 相似文献
53.
Urban heat island (UHI) often cause negative impact and has been linked to heart stroke rate, morality, human comfort, energy consumption and air pollution. Fortunately, urban green spaces have been considered as an effective element to mitigate UHI through their cooling effect. However, further empirical research is necessary in order to efficiently guide the design and planning of urban green space. We observed the impacts of urban park's tree, grass and waterbody on microclimate inside the Olympic park of Beijing during summer days. The results indicated that, on average, the park was 0.48–1.12 °C cooler during the day, as well as increased air humidity 2.39–3.74% and reduced human comfort index 1.02–2.43 to generate more comfortable thermal environment. Urban park's cluster trees with short ground vegetation generated higher cooling effect than single trees, grass and waterbodies; proper irrigation regime enhanced the cooling effect of grasses, even the irrigated grass have similar cooling effect with small waterbody on sunny, windless summer days. Therefore, we advise to increase undergrowth coverage and grass irrigation management in order to take advantage of cooling effect of urban parks. 相似文献
54.
GU Qing-fang YU Jie-zhong GUO Min-fang WEI Wen-yue XIAO Bao-guo ZHANG Guang-xian MA Cun-gen 《园艺学报》2019,35(12):2227-2234
AIM: To explore the neuroprotective effect of novel Rho kinase inhibitor FSD-C10 on Alzheimer disease (AD) model of APP/PS1 double transgenic (Tg) mice. METHODS: Male APP/PS1 Tg mice (n=20) at 8 months of age were randomly divided into 2 groups:model group and FSD-C10 treatment group. The mice were treated with normal saline or FSD-C10 (25 mg·kg-1·d-1) by intraperitoneal injection, once daily for 2 months. Age-and sex-matched wild-type (WT) mice without treatment were used as the control. The Morris water maze (MWM) test and SMART 3.0 behavioral record system were applied to examine and analyze the spatial cognitive function of the mice. The protein levels and distribution of Aβ, p-tau and synapse-associated proteins such as synaptophysin, α-amino-3-hydroxy-5-methyl-4-isoxazolepropionic acid receptor (AMPAR) and postsynaptic density protein 95 (PSD-95) were determined by immunofluorescence staining. The protein levels of phosphorylated amyloid precursor protein at Thr668[p-APP(Thr668)], beta-site APP-cleaving enzyme 1 (BACE1) and synapse-associated proteins in the brain were analyzed by Western blot. RESULTS: Compared with model group, FSD-C10 treatment significantly improved the cognitive function of the APP/PS1 Tg mice, accompanied by reduced Aβ deposition and p-tau level, increased protein level of p-APP (Thr668) in the central nervous system, decreased expression of BACE1, and increased expression of synapse-associated proteins in the brain of the mice (P<0.05). CONCLUSION: FSD-C10 has neuroprotective potential in the APP/PS1 Tg mice. The mechanism may be related to enhancing the non-amyloidogenic APP cleavage pathway, reducing the production of Aβ oligomers, the deposition of senile plaques and the amount of tau protein, up-regulating synapse-associated proteins, and increasing synaptic plasticity. 相似文献
55.
麦秸秆和沼液配施对水稻苗期生长和土壤微生物的调控 总被引:7,自引:0,他引:7
研究了等量氮素肥料处理下小麦秸秆全量还田结合化肥(S-CF)、小麦秸秆全量还田结合沼液(S-BS)和全量化肥(CF)处理对水稻幼苗生长、氮磷积累及土壤微生物群落的影响。结果表明,不同施肥处理的水稻幼苗生长明显被促进,其中CF处理的促进效果最好,其次是S-BS处理。S-BS处理的水稻叶片可溶性糖含量明显高于其他施肥处理,其叶片含氮量也明显高于CF处理。CF处理的土壤细菌总量明显高于S-BS处理,而S-BS处理的土壤细菌总量均显著高于对照(CK,不施肥)和S-CF处理;其中CF处理变形菌门细菌相对丰度显著高于其他处理。而CK和S-CF处理的真菌总量明显高于S-BS和CF处理,S-BS处理的真菌总量最低,其中,CK土壤优势真菌子囊菌门、担子菌门的相对丰度显著高于其他处理,S-CF处理土壤的壶菌门真菌相对丰度也显著高于其他处理。S-CF和S-BS处理的细菌Chao1丰富度指数和香农(Shannon)多样性指数要明显高于CF处理和CK,而S-CF处理的土壤真菌的Chao1指数和香农指数要明显高于CK,CF处理的土壤真菌Chao1指数和香农指数最低。秸秆、沼液短期替代化肥的处理下水稻植株生长低于全化肥处理的,但秸秆、沼液、化肥结合施用对水稻幼苗的促生作用依然很明显,尤其是秸秆还田结合沼液灌溉的全量替代化肥处理。全量替代化肥处理下,即秸秆和沼液处理的土壤质量和细菌丰富度及多样性即使在短期施用条件下也被明显促进。 相似文献
56.
57.
E. Valečková E. Ivarsson P. Ellström H. Wang K. Mogodiniyai Kasmaei H. Wall 《British poultry science》2020,61(4):433-441
ABSTRACT 1. This study investigated the effects of daily intake of silage or haylage on broiler production performance and organ development. Furthermore, effects of daily intake of Lactobacillus plantarum either via silage or by supplemented drinking water, on Campylobacter jejuni loads in faeces were studied. 2. To test this, a 42-d experiment using Ross 308 and a 63-d experiment with Rowan Rangers hybrids, were performed. Silage inoculated with L. plantarum strain 256 and haylage were fed in total mixed rations with mixtures of 85% of pellets and 15% of respective forage (DM-based weight). Feed intake (FI), forage intake, body weight (BW) and feed conversion ration (FCR) were monitored weekly. Mortality was recorded daily, and organ weights were registered at slaughter. Quantification of C. jejuni was performed by colony counts from faecal samples after culture on agar plates. 3. There was a negative effect of haylage on BW and FI in the fast-growing Ross 308 hybrid. Silage had a negative effect on BW only on week four and six. Water inoculated with L. plantarum 256 increased BW in the starter period. Interestingly, no significant adverse effect of forage inclusion was observed in the Rowan Ranger birds. 4. Relative weight of the emptied gizzard was higher in both Ross 308 and Rowan Ranger birds fed haylage and silage than in the control group. In Ross 308 birds, both forages significantly reased the relative weight of gizzard with digestive content when compared to birds fed solely pellets. 5. In both studies, higher consumption of silage than haylage was observed. 6. In conclusion, daily intake of L. plantarum 256 either via silage or supplemented in drinking water, was not effective in reducing the shedding of C. jejuni in either Ross 308 or Rowan Ranger hybrids at the end of the rearing period. 相似文献
58.
探究棘孢木霉GYSW-6m1对草莓炭疽病的生防机制、盆栽防治效果及其促生作用,为筛选用于草莓炭疽病绿色防控的高效生防菌提供资源及应用技术。采用平皿培养法、显微镜观察法和盆栽灌根法测定了棘孢木霉GYSW-6m1对草莓炭疽病的生防机制、盆栽防效及其对草莓幼苗的促生效果。结果显示,棘孢木霉GYSW-6m1对草莓炭疽菌LC0220具有较强的竞争、抗生和重寄生作用,菌株GYSW-6m1能迅速占领营养空间,对峙培养3、5和7 d对病菌LC0220抑制率分别为68.06%、71.03%和79.03%,病菌LC0220在含有菌株GYSW-6m1发酵代谢产物平板上培养3、5和7 d抑菌率分别为79.18%、75.81%和76.13%,菌株GYSW-6m1挥发代谢物对病菌LC0220菌丝生长几乎没有抑制作用,菌株GYSW-6m1菌丝可通过接触、缠绕和穿透病菌LC0220的菌丝并引起菌丝消解断裂。菌株GYSW-6m1对草莓炭疽病具有较好的盆栽防治效果,处理LC0220+GYSW-6m1防效最显著,防效高达87.23%,处理GYSW-6m1(3 d)+LC0220和LC0220(3 d)+GYSW-6m1防效分别为52.72%和44.76%。棘孢木霉GYSW-6m1对草莓幼苗具有明显的促生效果,株高、根长、植株总鲜重和植株总干重均显著增加,促生率分别为7.96%、10.42%、22.54%和34.21%。棘孢木霉GYSW-6m1可以作为一种重要的生防资源用于草莓炭疽病的防治,具有一定的实用开发潜力。 相似文献
59.
60.
Phytochemical prospecting was performed by HPLC-DAD. The Inhibitory Concentration of 50% of mortality the microorganisms (IC50) was determined and a cell viability curve was obtained. Minimum Fungicidal Concentration (MFC) was determined by subculture in Sabourad Dextrose Agar. The effect of the combination extract/fluconazole was verified by microdilution, with the extracts in subinhibitory concentrations (MFC/16). Caffeic acid was the major compound of both extracts, representing 6.08% in the aqueous extract and 7.62% in the ethanolic extract. The extracts showed a fungistatic effect (MFC ≥ 16,384 μg/mL). The IC50 results demonstrated that the combination of the extracts with fluconazole were more significant than the products tested alone, with values from 4.9 to 34.8 μg/mL for the ethanolic extract/fluconazole and 5 to 84.7 μg/mL for the aqueous extract/fluconazole. The potentiating effect of fluconazole action was observed against C. albicans and C. tropicalis. In C. krusei the aqueous extract had an antagonistic effect. 相似文献