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1.
为明确梨树行间种植油菜在改善梨果品质方面的作用,本试验比较了行间清耕和行间种植油菜处理下梨园土壤养分和访花昆虫情况,分析了梨果实坐果率、脱萼率及果实品质。结果表明,行间种植油菜较行间清耕处理显著提高了梨园土壤中速效磷和速效钾含量,增幅为36.6%和11.2%,此外可以增加昆虫特别是蜜蜂的访问量,减少金龟子的访问量;与行间清耕+自然授粉相比,行间种植油菜+自然授粉与人工授粉处理均可显著提高梨坐果率和脱萼率,增加果实重量和减小果实偏斜率;同时,行间种植油菜+自然授粉处理下梨果实可溶性固形物和总糖含量均最高,达13.83%和9.45%。行间种植油菜可以提高梨园土壤营养和授粉昆虫的数量,增加梨坐果和改善果实品质。  相似文献   

2.
正据《中国南方果树》2020年第3期《种植油菜对玉露香梨着果及果实品质的影响》(作者李昕照等)报道,为明确梨树行间种植油菜在改善果实品质方面的作用,试验比较了行间清耕和行间种植油菜处理下梨园土壤养分和访花昆虫情况,以及着果率、脱萼率及果实品质。结果表明,行间种油菜较行间清耕处理显著提高了梨园土壤中速效磷和速效钾含量,增幅为36.6%和11.2%,可以增加昆虫特别是蜜蜂的访问量,减少金龟子的访问量;与行间清耕+自然授粉相比,行间种油菜+自然授粉与人工授粉处理  相似文献   

3.
河北坝上林间种草试验初报   总被引:4,自引:1,他引:3  
河北坝上地区疏林地面积大,地表空闲裸露,低产低质,为此于1986-1988年进行了林间种植豆科牧草试验,结果表明:增产干草843-3685.5kg/hm^2,同时杨树高度增加15.1-28.7cm,杨树直径增粗0.1-0.55cm,地表覆盖率也显著增加,土壤有机质增加0.215%,速效氮增加22.29ppm。实践证明,疏林地林间种草方法可行,效益显著。  相似文献   

4.
在内蒙古河套平原碱化盐土上对草木樨等5种牧草进行开沟试种试验表明,这几种牧草都适宜采取开沟种植方法,其中一年生草木樨和二年生草木樨适宜性最佳,而且耐卤性也较强,一年生草木樨在10-30厘米(沟底)表层土壤含盐0.9%时,出苗率为65%,二年生草木樨在10-30cm(沟底)表层土壤含盐1.14%时,出苗率为60%,保苗率均在85%以上,种植时要进行洗碱排盐,种子处理和改进种植技术。  相似文献   

5.
研究了不同土壤管理模式下梨园土壤主要微生物类群(细菌、真菌、放线菌)分布和数量,结果表明:0~20cm处土层土壤微生物数量显著高于20~40cm处土层,细菌数量明显多于真菌和放线菌的数量,生草梨园的土壤微生物类群(细菌、真菌、放线菌)数量均多于种养结合的梨园,而种养结合梨园的土壤微生物类群(细菌、真菌、放线菌)数量又高于清耕模式梨园。  相似文献   

6.
为明确苹果(Malus pumila)树行间种植不同豆科牧草后对园中土壤微生物区系和土壤酶活性的影响,于苹果园建植第1年,在果树行间种植百脉根(Lotus cornioulatus)、白三叶(Tri folium repens)和红三叶(T.pretense),以果树行间“清耕”土壤为对照,研究0~20 cm土层中微生物总数、细菌、真菌、放线菌的数量及其比例和蔗糖酶、脲酶、过氧化氢酶活性的变化规律.结果表明:园中土壤微生物区系中,细菌占土壤微生物总数的77%以上,放线菌次之,真菌最少,为0.01%~0.04%;种草后,土壤中放线菌比例减少,细菌增加,此趋势随土壤深度增加而加剧,0~10 cm土层中增减比例幅度为1.2%~4.4%,而10~20 cm土层中为18%.种草后,放线菌数量减少,真菌数量、蔗糖酶及脲酶活性增加,增减幅度因草种及土壤深度而异,而对过氧化氢酶活性无影响.在种植百脉根、白三叶的0~10 cm土层中微生物总数、细菌数量减少,而种植红三叶的10~20 cm土层中微生物总数、细菌数量增加;种植百脉根后,0~10 cm蔗糖酶活性、0~20 cm脲酶活性升高,种植白三叶、红三叶后,0~20 cm土壤蔗糖酶、10~20 cm土壤脲酶活性升高.说明种草可改变苹果园土壤微生物区系和酶活性,此作用和草种、土壤深度密切相关.  相似文献   

7.
在果园内种植对果树生产有益的草,是果园目前最好的土壤管理方法,它主要有以下优点:防止或减少水土流失。果园种草后,降雨和灌溉的地表径流大大减少,随水流失的土壤也很少,尤其是山坡地和沙滩地果园,效果更明显。增加土壤有机质含量,提高土壤肥力。刈割后铺在地上的草及草死亡的根,都是土壤有机质稳妥可靠的来源。经试验,在果园种植白三叶或黑麦草,经过5年,土壤有机质可由0.5%~0.7%增加到1.5%~2%。在种草的条件下,果园土壤表层的季节性和一天中昼夜温度的变化小。如一些沙土地果园,在清耕条件下,夏季炎热的中午和下午…  相似文献   

8.
猪煤烟污染型硒中毒的调查   总被引:5,自引:0,他引:5  
1980-1989年湖北省恩施自治州宣恩县杉砣村、巴东县南潭村的猪相继发生以脱毛、脱蹄为主要症状的中毒病,发病率为27.3%,病死率为75.3%。调查发现,处于高硒地区的这两个材的农民有用高硒石煤煤烟熏土壤作肥料的习惯,致使土壤本含量增加数十倍,导致农作物及饲草含硒量成倍增加。经测定,用石煤煤烟熏土12h后,土壤总硒量增加14倍;在烟熏了3h的农田种植油菜,仅53d其含硒量较对照组增加36.4%,  相似文献   

9.
生草配合施用有机肥对省力高效梨园土壤的培肥效应研究   总被引:2,自引:0,他引:2  
为了推动果园生草在我国的推广应用,研究生草配合施用有机肥土壤管理方式对省力高效现代梨园土壤养分的作用效应,在冀中平原的“雪青”梨园,以常规清耕梨园为对照,研究省力高效梨园生草4年和生草8年的培肥效应,于2014年梨树萌芽期,在80 cm土层内分10 cm一层取样,分别测定不同土层的有机质、大量元素和微量元素含量,比较不同处理土壤营养元素的变化特征。结果表明,生草梨园0~50 cm土层有效养分含量均达到较高水平;与常规梨园相比较,这种管理模式短期(4年)增加了0~10 cm土层碱解氮、速效磷、有效锌含量和0~20 cm土层速效钾、有效铁含量,长期(8年)显著增加了0~10 cm土层有机质和碱解氮含量、0~20 cm有效铁和有效锰含量、0~30 cm速效磷和有效铜含量、0~40 cm有效锌含量和0~50 cm速效钾含量。显著降低了0~30 cm土层pH值,明显提高了河北省石灰性梨园土壤磷、铁、锌的有效性。长期生草配合施用有机肥能够增加上层土壤有效养分含量,生草8年后,0~50 cm土层速效磷、速效钾和有效锌占0~80 cm土层比重分别达到92%、82%和88%,为梨园提供充足营养的同时降低了环境污染的风险,有利于梨园土壤培肥和果园的可持续发展。  相似文献   

10.
本试验以粉垄拖拉机整地种植豆科牧草白花扁豆、禾本科牧草台湾甜象草作试验区,用中型拖拉机整地种植上述牧草为对照区进行为期1年的种植试验来观察粉垄专用拖拉机的使用效果。结果表明,试验区禾本科牧草台湾甜象草优势不明显,豆科牧草白花扁豆则效果显著,经测定试验区比对照区根数增加17.6%-60.8%,主根长增加10.4%-90.2%,根瘤数增加4:2.7%-223.3%。根瘤直径在0.5-1.5(厘米)及〉1.5(厘米)之和占总根数的比率试验区为51.5%-72.8%,对照区为O%-44.7%。试验组比对照组植株分蘖数增加47.8%-118.1%,株高增长20.4%-106.9%,植株产量增加14.8%-20.8%。粗蛋白、粗脂肪分别高于对照区2.63和1.74个百分点。本试验结果证明,粉垄拖拉机整地比用中型拖拉机整地后种植白花扁豆效果好,值得推广。  相似文献   

11.
Sanguinarine (SA) is a benzo[c] phenanthridine alkaloid which has a variety of pharmacological properties. However, very little was known about the pharmacokinetics of SA and its metabolite dihydrosanguinarine (DHSA) in pigs. The purpose of this work was to study the intestinal metabolism of SA in vitro and in vivo. Reductive metabolite DHSA was detected during incubation of SA with intestinal mucosa microsomes, cytosol, and gut flora. After oral (p.o.) administration of SA, the result showed SA might be reduced to DHSA in pig intestine. After i.m. administration, SA and DHSA rapidly increased to reach their peak concentrations (Cmax, 30.16 ± 5.85, 5.61 ± 0.73 ng/ml, respectively) at 0.25 hr. Both compounds were completely eliminated from the plasma after 24 hr. After single oral administration, SA and DHSA rapidly increased to reach their Cmax (3.41 ± 0.36, 2.41 ± 0.24 ng/ml, respectively) at 2.75 ± 0.27 hr. The half-life (T1/2) values were 2.33 ± 0.11 hr and 2.20 ± 0.12 hr for SA and DHSA, respectively. After multiple oral administration, the average steady-state concentrations (Css) of SA and DHSA were 3.03 ± 0.39 and 1.42 ± 0.20 ng/ml. The accumulation indexes for SA and DHSA were 1.21 and 1.11. The work reported here provides important information on the metabolism sites and pharmacokinetic character of SA. It explains the reasons for low toxicity of SA, which is useful for the evaluation of its performance.  相似文献   

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The prevalence of Salmonella in fresh pork cuttings in Denmark in the years 2002 and 2006 was investigated at retail and compared with the retail supply pattern. A total of 1025 and 3473 samples were taken in 2002 from butcher's shops and supermarkets, respectively. The corresponding numbers in 2006 were 259 from butchers' shops and 628 from supermarkets. In 2002, 1.2% of all samples were positive for Salmonella; butchers' shops and supermarkets had 1.8% and 1.0% positive samples, respectively. The overall prevalence in 2006 was 4.2%, with prevalence of 8.1% and 2.6% for butchers' shops and supermarkets, respectively. Hence, increases around 3- to 5-fold were found. There was neither observed any parallel increase in Salmonella positive carcasses in Danish slaughterhouses during the study period, nor were any changes in supply routes towards slaughterhouses with higher prevalence observed, which could explain the apparent increase. We hypothesize that hygiene levels and ability to avoid cross-contamination and prevent growth of the organism, in the meat processing chain after slaughter were the most likely responsible factors. Results from this study indicate that the hygiene performance, particularly at retail, has a significant impact on the occurrence of Salmonella. This implies that there is no direct link between slaughterhouse Salmonella surveillance data and the level of Salmonella contamination at retail. To improve risk assessment of Salmonella in fresh pork meat, this study underlines the need for comprehensive retail data.  相似文献   

15.
Rectal swabs were collected from 437 household and 491 stray dogs in northern Taiwan from May 2003 to June 2005 to investigate the prevalence and antimicrobial susceptibilities of salmonellae and campylobacters. The results revealed that 2.1% of household dogs and 6.3% of stray dogs were positive for salmonellae, with Salmonella Duesseldorf being the most dominant serotype in both. Additionally, 2.7% of the household dogs and 23.8% of the stray dogs were positive for campylobacters. Campylobacter jejuni was the most prevalent species (86.8%), followed by C. upsaliensis (9.3%) and C. coli (3.9%). Both salmonella and campylobacter isolation rates from the stray dogs were significantly higher than those from the household dogs (p < 0.01). The susceptibility of 33 C. jejuni isolates to eight antimicrobials was studied by the E-test. A high rate of resistance was observed to azithromycin (93.9%), clindamycin (87.9%), erythromycin (81.8%), tetracycline (78.8%), chloramphenicol (69.7%), nalidixic acid (51.5%), gentamicin (33.3%), and ciprofloxacin (18.2%). The susceptibility of 40 Salmonella isolates to 15 antimicrobials was also studied by the disc-diffusion method. All the Salmonella isolates were susceptible to ciprofloxacin and ceftriaxone. Resistance was observed most frequently to tetracycline (77.5%), chloramphenicol (52.5%), and ampicillin (50%).  相似文献   

16.
Bartonella and Babesia infections and the association with cattle breed and age as well as tick species infesting selected cattle herds in Taiwan were investigated. Blood samples were collected from 518 dairy cows and 59 beef cattle on 14 farms and 415 ticks were collected from these animals or in a field. Bartonella and Babesia species were isolated and/or detected in the cattle blood samples and from a selected subset (n = 254) of the ticks either by culture or DNA extraction, PCR testing and DNA sequence analysis. Bartonella bovis was isolated from a dairy cow and was detected in 25 (42.4%) beef cattle and 40 (15.7%) tick DNA samples. This is the first isolation of B. bovis from cattle in Asia and detection of a wide variety of Bartonella species in Rhipicephalus microplus. Babesia spp. were detected only on one farm from dairy cows either infected by Babesia bovis (n = 10, 1.9%) or B. bigemina (n = 3, 0.6%).  相似文献   

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18.
Commercial feedstuffs are a basic element in modern pet husbandry in the world. In dogs, the effect of mycotoxins is severe and can lead to death. Few reports on the influence of dietary mycotoxins were found in the scientific literature. The aims of this work were to isolate and identify the mycoflora and to determine the aflatoxins (AFs) natural occurrence in raw materials and ready dry pet food. Therefore, the aflatoxigenic capacity of Aspergillus flavus species was investigated. Aspergillus was the prevalent genera (65-89%) followed by Penicillium and Fusarium spp. Aspergillus flavus was the most prevalent species, followed by Aspergillus sydowii, Aspergillus fumigatus and Aspergillus versicolor. Aspergillus flavus frequencies ranged from 58% to 86% except in sorghum meal. All samples assayed (except corn grains and ready pet food) showed Fusarium spp. contamination. Corn meal and corn meal and gluten samples had 100% Fusarium verticillioides. Fusarium graminearum was isolated from sorghum meal. Aspergillus flavus strains (75%) isolated from raw materials and 57% from pet food were able to produce AFs. All samples showed AFs contamination percentages over 70%; corn and sorghum meal obtained the highest AFs levels. Ready pet food did not show quantitative levels of the tested toxins. This is the first report of the aflatoxigenic capacity by A. flavus from Brazilian pet food.  相似文献   

19.
Helminth and protozoan parasites in dogs and cats in Belgium   总被引:1,自引:0,他引:1  
This study investigates the level of helminthic and protozoal infestation over the last 10 years in strays, well-cared-for dogs and cats. Determination of the prevalence of infections was based either on faecal examination or on worm counts at necropsy. Of 2324 faecal flotations (NaCl sp.gr. 1.20) of stray dogs, 34.2% had eggs or proglottids of one or more worm species consisting of Toxocara canis (17.4%), Toxascaris leonina (10.1%), Uncinaria stenocephala (11.4%), Trichuris vulpis (7.0%) and cestodes (2.1%). Isospora oocysts were observed in 5.2% of the dogs. The data on the distribution of the various worm species in the positive dogs indicate that T. canis eggs were by far the most common (50.9%). Necropsy data from 212 infected dogs indicate that 38.9% were infected with T. canis and 33.7% with T. leonina. The overall prevalence of worm infestation of 246 well-cared-for kennel dogs, based on worm egg counts by the McMaster technique, was 36.1%. Of 30 feline faecal samples examined by flotation, 83.3% were positive for parasites, including Toxocara cati (60%), Ancylostoma tubaeformae (36.6%), Taenia (Hydatigera) taeniaeformis (20%) and coccidia (30%). Toxocara cati was the most frequently found worm species at the necropsy of 25 cats (52%). Toxoplasma was not observed.  相似文献   

20.
Chlortetracycline hydrochloride was administered intra-arterially (11 mg/kg) and as an oral drench (33 mg/kg) to ten 21.0-31.5-kg pigs. Five of the pigs were fasted 18 h prior to dosing and five of the pigs were fed ad libitum prior to dosing. The mean volume of distribution determined by area-under-the-curve calculations for the fasted pigs (0.967 +/- 0.210 l/kg) was significantly less (P less than 0.05) than the mean volume of distribution for the fed pigs (1.39 +/- 0.31 l/kg). Mean total body clearance of the drug was also significantly less (P less than 0.05) in the fasted pigs (0.165 +/- 0.055 l/kg/h) as compared to the fed pigs (0.307 +/- 0.053 l/kg/h). The elimination constants (beta) were not found to be statistically different (P less than 0.05): 0.1811 +/- 0.0057 for the fasted pigs; 0.2260 +/- 0.0461 for the fed pigs. The bioavailability for both groups was similar; 19.12 +/- 8.3% for the fasted pigs and 17.88 +/- 5.3% for the fed pigs. In a second experiment three groups of six pigs which weighed 34.5-44.1 kg were fed a corn-soy diet ad libitum. The rations were fortified with chlortetracycline at 100, 400 or 1000 mg chlortetracycline hydrochloride/kg feed. Chlortetracycline concentrations were determined in plasma samples collected over a 6-day period. Plasma chlortetracycline concentrations reach a plateau within 24 h after initial access to the trial diets and were highly correlated with the dose of the drug consumed (r2 = 0.97).  相似文献   

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