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41.
Variable adventitious rhizogenesis of juvenile shoot cuttings was observed in seven half-sib families (TP-1, BAN-1, AN-3,
JR-3, SL-16, UM-3, and UM-5) of Albizia procera Benth. Treatment with IBA invariably promoted sprouting by 8%, adventitious rooting by 218%, root number by 869%, and root
length by 36.4% compared with the control. Interaction between families and IBA treatment significantly enhanced sprouting
and root length in BAN-1, JR-3, UM-3, and UM-5, and root number in all families, but had a significant suppressive effect
on sprouting in AN-3. Treatment with IBA increased family heritability (h
f
2) 1.38-fold for sprouting, 2.86-fold for adventitious rooting, and 10.86-fold for root number, but reduced family heritability
by a factor of 8.25 for root length. Thus, direct genetic effects seem to have strongly affected sprouting and adventitious
rooting, with IBA playing an auxiliary role, but had little effect on root number and length, for which IBA had a dominant
regulatory role. 相似文献
42.
Mohammad Akhtar 《Integrated Pest Management Reviews》2000,5(1):57-66
Plant products are receiving greater attention as prophylactics against several species of plant-parasitic nematodes. Numerous experiments have shown the potential nematicidal value of plant parts and their by-products when incorporated into soil or when the plants themselves are interplanted as seedlings among crop plants. Various products (oils, cakes, extracts, etc.) prepared from the leaves and seeds of the neem plant (Azadirachta indica A. Juss) (Family Meliaceae) have been reported as effective protectants against nematode pests when used as root-dips and seed treatments. Nemato-toxic compounds of the neem plant, especially the azadirachtins, are released through volatilization, exudation, leaching and decomposition. The modes of action of these compounds are complex, and a number of mechanisms in relation to nematode management are yet to be fully explored. This review critically assesses the potential of these products in the management of nematodes in tropical agriculture. 相似文献
43.
Shahida Akhtar Misbahuddin Pirzada M. H. Siddiqui Umar K. Baloch 《Pest management science》1998,52(3):218-222
Experiments were carried out to study the influence of two types of neem cake (solvent-extracted, NC-I and expeller-extracted, NC-II) on the persistence in soil of diazinon and endosulfan applied as commercial formulations. It was found that both types of neem cake applied at 10, 20 or 30 g ha-1 prolonged the period of degradation as compared with soils without neem cake amendment, and hence increased the persistence of the insecticides. There was little difference in the effect of the two types of neem cake. Treatment of the soil with insecticide 10 days after amendment with neem cake did not lead to any increase in persistence; for a good response, treatment of soil with insecticide and with neem cake must be done at the same time. © 1998 SCI. 相似文献
44.
M. Ramzan M. Akhtar F. Muhammad I. Hussain E. Hiszczyńska-Sawicka A. U. Haq M. S. Mahmood M. A. Hafeez 《Tropical animal health and production》2009,41(7):1225-1229
Toxoplasmosis, an infection caused by Toxoplasma (T.) gondii Apicomplexa protozoan, is widespread in humans and other animal species, having already been reported in many countries and
different climates. In Pakistan, no data is available on this aspect among food animals. This study was undertaken to determine
the seroprevalence of T. gondii infection in sheep and goats. A total of 200 serum samples from sheep and goats, were collected from urban area of Rahim
Yar Khan (Punjab), Pakistan and tested for Toxoplasmosis with a commercial latex agglutination kit (Eiken Chemical Co., Ltd.
Japan). The overall seroprevalence of Toxoplasmosis was 19%. Goats had a significantly higher (p < 0.01) prevalence (25.4%)
as compared to the sheep (11.2%); and higher (p < 0.01) in the female (24%) than in the males (19%) for both species. In the
present study the male (both in sheep and goat) are found less seropositive T. gondii (OR = 0.23; 99% C.I. = 0.01, 1.81) as compared to female sheep and goat. The prevalence was significantly higher (p < 0.01)
in adult sheep than younger animals. Among both the sheep and goats the group from 1–1.5 years are highly seropositive (OR = 1.75;
99% C.I. = 0.47, 6.51) as compared to the group less than one year of age followed by the 2–2.5 years age group (OR = 1.63;
99% C.I. = 0.50, 5.74) whereas group with more than 3 years of age least seropositive. 相似文献
45.
Faqir Muhammad Masood Akhtar M. Irfan Anwar M. Javed Arshed 《Veterinary research communications》2009,33(8):971-977
Ciprofloxacin was administered intravenously @ 5 mg/kg body weight to six healthy dogs. After a washout period of two weeks,
fever was induced by injecting Escherichia (E) coli endotoxin. Ciprofloxacin was administered again. Blood samples were collected at various time intervals and analyzed for
ciprofloxacin with HPLC. The kinetic analysis revealed the volume of distribution in healthy vs. febrile dogs as 2.12 ± 0.32
vs. 1.79 ± 0.43 L/Kg, respectively. The elimination half life was 2.23 ± 0.78 and 2.07 ± 0.74 hours in healthy and febrile
dogs, respectively. Similarly, dogs under healthy and febrile conditions showed comparable total plasma clearance of 0.66 ± 0.06
and 0.60 ± 0.07 L/Kg/h, respectively. All these and other investigated kinetic parameters were statistically non significant.
This study concludes that the pharmacokinetic behavior of ciprofloxacin is similar under healthy and febrile conditions. Thus,
the kinetic studies of fluoroquinolones conducted in normal/healthy animals may be used to depict the pharmacokinetic parameters
in diseased animals. 相似文献
46.
The present study was designed as a repeated dose 28-day oral toxicity study in rodent. All the rats were randomly divided into five groups (C1, C2, T1, T2 and T3) each containing 10 Wistar rats (5 male and 5 female). Group C1 served as control as no treatment was administered. Group C2 was administered groundnut oil (1 ml/100 g b.wt) and served as vehicle control. Group T1 was put on high dose 153.33 mg/kg b.wt (LD50/3), while group T2 received intermediate dose of 92 mg/kg b.wt (LD50/5), and group T3 was administered low dose of 46 mg/kg b.wt (LD50/10) of Prallethrin suspended in 1 ml/100 g b.wt of groundnut oil. Blood samples were collected from all groups on the 7th, 14th, 21st and 28th day of the experiment for measurement of serum glucose, serum urea, serum triglyceride, serum cholesterol, serum aspartate aminotransferase (AST), serum alanine aminotransferase (ALT) and serum alkaline phosphatase (ALP). According to data obtained on the 7th day of the study, no statistically significant change in any of the treatment groups was observed as compared to the control group. On the 14th day of the study, in comparison to the control group, triglyceride level and ALP activity were found to be significantly increased in the group T1 female and group T1 male rats respectively. On the 21st day of the study, compared to the controls, significant increase in cholesterol and ALP levels were present in both T1 and T2 females and in addition to this total protein and triglycerides levels were also significantly increased in group T1 female rats. In group T1 male total protein, triglycerides, ALT and ALP activity was found to be increased significantly as compared to healthy control group. On the 28th day, all the recorded biochemical parameters were found to be significantly increased, except BUN and AST in group T1 female rats. In group T2 female rats, significantly increased cholesterol, ALT and ALP levels were observed. In group T3 female rats, none of the parameters were found to be significantly affected. Among male rats, only total protein level was found to be increased in groups T2 and T3. Whereas, total protein, triglyceride, ALT and ALP were significantly elevated in group T1 male rats at the end of the study. In conclusion, the results of this study demonstrate that subacute oral administration of Prallethrin; at dose levels of 1/3 LD50 and 1/5 LD50 for 28 days induces moderate toxic effects on different biochemical parameters. 相似文献
47.
Min BE Feldman TS Ali A Wiley G Muthukumar V Roe BA Roossinck M Melcher U Palmer MW Nelson RS 《Phytopathology》2012,102(2):166-176
Native virus-plant interactions require more understanding and their study will provide a basis from which to identify potential sources of emerging destructive viruses in crops. A novel tymovirus sequence was detected in Asclepias viridis (green milkweed), a perennial growing in a natural setting in the Tallgrass Prairie Preserve (TGPP) of Oklahoma. It was abundant within and frequent among A. viridis plants and, to varying extents, within other dicotyledonous and one grass (Panicum virgatum) species obtained from the TGPP. Extracts from A. viridis containing the sequence were infectious to a limited number of species. The virus genome was cloned and determined to be closely related to Kennedya yellow mosaic virus. The persistence of the virus within the Oklahoma A. viridis population was monitored for five successive years. Virus was present in a high percentage of plants within representative areas of the TGPP in all years and was spreading to additional plants. Virus was present in regions adjacent to the TGPP but not in plants sampled from central and south-central Oklahoma. Virus was present in the underground caudex of the plant during the winter, suggesting overwintering in this tissue. The RNA sequence encoding the virus coat protein varied considerably between individual plants (≈3%), likely due to drift rather than selection. An infectious clone was constructed and the virus was named Asclepias asymptomatic virus (AsAV) due to the absence of obvious symptoms on A. viridis. 相似文献
48.
49.
Organic soil amendments in relation to nematode management with particular reference to India 总被引:2,自引:0,他引:2
The addition of organic materials to soil has been used in managing plant-parasitic nematodes and has resulted in increased crop yield. Research on the utilization of waste materials such as oilseed cakes, chitin, compost, livestock and poultry manures, and cellulosic wastes appears promising for reducing populations of plant-parasitic nematodes. Nitrogen based amendments, plant phenolics, nematotoxic chemicals, development of predators and parasites of nematodes and microorganism stimulation have been considered to be promising agents for nematode management. In addition, organic amendments change the physical as well as the trophic structure of soil, which affects the pathogen development and overall plant growth performance. Mechanisms of action of organic soil amendments in relation to nematode management are yet to be fully explored.Plant Protection Division, Institute of Agriculture 相似文献
50.
M. Humayoun Akhtar Robert M. G. Hamilton H. Locksley Trenholm 《Pest management science》1987,20(1):53-73
Radiolabelled racemic cypermethrin, and the cis and trans isomers of 3-(2,2-dichlorovinyl)-2,2-dimethylcyclopropanecarboxylic acid (labelled at C-1 of the cyclopropane ring) were each separately administered orally in feed for three consecutive days to White Leghorn laying hens. The amount of individual compound dosed was approximately 7.5 mg per hen per day. Radiocarbon was eliminated very rapidly in excreta. Tissue residues were generally very low with the exception of fat depots, but trace amounts of radiocarbon residues were still detectable in fat, liver and kidney 11 days post-treatment. Residues were detected in the egg albumen of hens treated with cypermethrin and cis isomer of the acid, but none was detected from trans acid. Metabolites identified included products arising from the hydrolysis of the ester bond of cypermethrin, followed by oxidative attack on one or both methyl groups. The rate of oxidative attack on methyl groups was influenced by the geometry of the dichlorovinyl group. On the basis of the metabolites identified a metabolic pathway for cypermethrin in laying hens was proposed which included hydrolysis of the ester bond followed by oxidation of methyl group(s). The data indicate that use of cypermethrin as recommended should not produce residues in eggs and meat of laying hens at levels that are of toxic concern. 相似文献