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1.
Wild pigs are a free-ranging invasive species capable of inflicting significant damage on rural property. Wildlife management personnel may benefit from understanding the negative societal impact of wild pigs. A statewide mail survey of randomly selected landowners was conducted in rural Tennessee counties known to have wild pigs. The economic value of damage caused by wild pigs in 2015 in these counties was estimated at $26.22 million, whereas the cost incurred in control and eradication was $2.09 million. Input-output modeling of damage in these counties on the state’s economy showed $32.8 million in lost industrial output, $4.6 million in lost labor income, and 332 jobs or job equivalents affected. Findings are useful in understanding the types of damage, and the extent of these impacts on the rural economy. They could also facilitate comparing the expected benefit with the cost of control programs in Tennessee and comparable areas facing similar invasions from wild pigs.  相似文献   
2.
A study was conducted on the stability of monoclonal antibody (MAb) in the hepatopancreas and hemolymph of Penaeus monodon and its effect on protection against white spot syndrome virus (WSSV) upon challenge. MAb C-5 raised against WSSV was purified and coated onto a commercial shrimp feed at dosages of 5, 10 and 15 mg/kg feed. The feed was fed to P. monodon and stability of the MAb in hepatopancreas and hemolymph was determined by immunodot and Western blot. Immunodot results indicated the presence of MAb for 2 h post-feeding in hepatopancreas and hemolymph which was dose-dependent. MAb was also detected in hemolymph by Western blot up to 1 h post-feeding. Shrimp fed with MAb were challenged with WSSV by oral and injection methods. In shrimp fed with 15 mg antibody/kg feed (0.45 μg MAb/g shrimp/day) WSSV infection significantly delayed both in oral and injection challenges with a survival of 65 and 70 % (p < 0.05), respectively, during 15 days post-challenge. MAb was stable in shrimp for passive immunization against WSSV and could be a potential tool for prophylaxis against the virus.  相似文献   
3.
Pot culture experiment was conducted to evaluate the suitability of extractants and to determine the critical limit of boron (B) in soil and mustard plant in Inceptisols of Varanasi. Twenty-one bulk soil collected from different locations were used for growing mustard. Five extractants, namely hot water, hot 0.01molar (M) calcium chloride (CaCl2), 0.01M CaCl2 + 0.05 M mannitol, 1.0 M ammonium acetate (NH4OAC) and 0.05 M hydrochloric acid (HCl), were assessed by correlating the amount of extractable B in untreated and B fertilizer-treated soil with Bray’s per cent yield, plant tissue B concentration and B uptake by mustard. Similarly, correlation coefficients of the B extracted by different extractants and soil properties were calculated. The suitability of B extracted by different extractants was in the order of hot 0.01M CaCl2 (HCC-B) > hot water (HW-B) > 1.0 M NH4OAC (AA-B) > 0.05M HCl (HA-B) > 0.01M CaCl2 + 0.05M mannitol (CCM-B). The critical limits of extractable B in soil as determined by the graphical procedure were 0.54, 0.60, 0.36, 0.45 and 0.45 mg kg?1 and the statistical procedures were 0.54, 0.60, 0.38, 0.46 and 0.48 mg kg?1 with HW-B, HCC-B, CCM-B, AA-B and HA-B, respectively. Soil containing available B below the critical limit responded to B fertilization.  相似文献   
4.
Prescribed burning is a widely used tool in forest and grassland management. However, because fire that escapes from a prescribed burn accidentally may cause property damage, injuries, and even human casualties, purchasing insurance to cover such damages may be beneficial for prescribed burn practitioners. Given that insurance coverage for prescribed fire is recently emerging, factors that determine burners’ decisions to purchase such insurance are largely unknown. On the basis of data from a survey of prescribed burn practitioners in 14 southern and midwestern states, we modeled prescribed burners’ likelihood of purchasing insurance with respect to demographic characteristics, land management objectives, and importance placed on regulatory compliance and land use practices. Results suggest that prescribed burn practitioners are more likely to obtain such insurance if they are landowners themselves or have a written prescribed burn plan. Age of respondents and the level of importance they place on compliance with environmental laws also had a significant positive effect on the likelihood of obtaining insurance coverage. Respondents were less likely to purchase insurance if their land management objective was to control invasive plants or they considered the availability of lower-cost alternatives for woody plant removal an important factor in deciding whether or not to conduct prescribed burns. These findings shed light on underlying factors influencing insurance coverage for prescribed burning and are potentially beneficial for promoting the acquisition of insurance among burn practitioners.  相似文献   
5.
Oligodeoxynucleotides (ODNs) with unmethylated CpG dinucleotides mimic the immunostimulatory activity of bacterial DNA in vertebrates through the recognition of cellular Toll-like receptor 9 (TLR9). We previously demonstrated that CpG motif, 5′-GACGTT-3′ (1668), and 5′-GTCGTT-3′ (2395) were highly immunostimulatory in cobia. In this study, motifs containing CpA, CpC, and CpT were used to evaluate their effects on cobia TLR9 (RCTLR9) gene expression. RCTLR9 expression increased significantly in response to CpT ODN in comparison with other ODN motifs. The optimal dosage of CpT ODN was 10 µg/fish. Furthermore, when the endosomal acidification was blocked using chloroquine immersion, the CpT ODN-induced expression of RCTLR9 in spleen and liver was inhibited in a dose-dependent manner. Our results demonstrated that ODNs containing motifs other than CpG, such as CpT ODN, can stimulate RCTLR9 expression, which is mediated, at least partially, by the interaction between CpT ODN and RCTLR9.  相似文献   
6.
A greenhouse experiment was conducted in the Department of Soil Science and Agricultural Chemistry, Institute of Agricultural Sciences, Banaras Hindu University, Varanasi (U.P.), India, during kharif 2013 to find out the effect of biochar and sewage sludge (SS) on growth, yield, and micronutrient uptake in rice crop. Nine treatments were employed using six different doses of biochar (2.5, 5.0, 7.5 10, 15, and 20 t ha?1) amended with a fixed dose of SS (30 t ha?1) and 50% recommended dose of nitrogen (50% RDN), i.e., 60 kg ha?1. Other three treatments were absolute control (no fertilizers), 100% recommended dose of fertilizers (100% RDF) which was 120:60:60 kg ha?1 as nitrogen (N): phosphorus pentoxide (P2O5):dipotassium oxide (K2O), and 30 t ha?1SS + 50% RDN. Experimental results showed a significant increase in yield of rice crop with increasing levels of biochar along with SS. Application of biochar at 20 t ha?1 along with 30 t ha?1SS increased grain yield to the extent of 2.5 times over absolute control (no fertilizers) and 8.5% over control (100% RDF). The uptake of iron (Fe), copper (Cu), zinc (Zn), and manganese (Mn) (micronutrients) increased significantly with graded doses of biochar application from 2.5 to 20 t ha?1 in the soil. The maximum micronutrient uptake and grain yield of rice were found in T9 where 30 t ha?1SS along with 20 t ha?1 biochar was applied with only 50% RDN. The maximum availability of micronutrients in soil was found with 30 t ha?1 of SS + 50% RDN (T3) followed by conjoint application of 20 t ha?1 of biochar and 30 t ha?1 SS + 50% RDN (T9).  相似文献   
7.
Functional response of Harmonia dimidiata (Fab.) to melon aphid, Aphis gossypii Glover was studied in the laboratory at 25 ± 0.5 °C, 70 ± 5% RH and 12L:12D photoperiod. All the predator stages exhibited Type II functional response to the aphid. Based on Rogers’s random predator equation the predator’s attack rate was lowest (0.128) in the first-instar and highest (0.21) in the adult stage. Handling times of the adult beetle and the fourth-instar (0.148 and 0.164 h, respectively) were much shorter than other stages. The maximum number of aphids that could be consumed over a period of 24 h by first, second, third and fourth instar; and adult of H. dimidiata was estimated to be 47.2, 80.2, 79.7, 146.2 and 161.7 aphids/ predator. Functional response parameters indicate that the adult beetles and the fourth-instar were the most voracious stages and could be important for the biological control of the aphid.  相似文献   
8.
A monoclonal antibody-based flow-through immunoassay (FTA) was developed using a nitrocellulose membrane placed on the top of adsorbent pads enclosed in a plastic cassette with a test zone at the center. The FTA could be completed within 10 min. Clear purple dots against a white background indicated the presence of Aphanomyces (A.) invadans. The FTA limit of detection was 7 µg/mL for A. invadans compared to 56 µg/mL for the immunodot. FTA and polymerase chain reaction (PCR) could detect A. invadans in fish tissue homogenates at a 10-11 dilution compared to a 10-8 dilution by immunodot. In fish suffering from natural cases of epizootic ulcerative syndrome (EUS) collected from Mangalore, India, FTA and PCR could detect A. invadans in 100% of the samples compared to 89.04% detected by immunodot. FTA reagents were stable and produced expected results for 4 months when stored at 4~8℃. This rapid test could serve as simple and cost-effective on-site screening tool to detect A. invadans in fish from EUS outbreak areas and in ports during the shipment of live or frozen fish.  相似文献   
9.
Myzus persicae (Sulzer) is an economically important agricultural pest with over 500 known host plants in the world. The present study recorded the major parasitoids found parasitizing M. persicae on sweet pepper (Capsicum annuum [L.]) crops in greenhouses in Himachal Pradesh, India. Three species of hymenopteran parasitoids were reared from M. persicae from this source: Aphelinus asychis Walker (Aphelinidae), Aphidius matricariae Haliday (Braconidae), and Aphidius ervi (Haliday) (Braconidae), with parasitism rates per sample date ranging from 2.3–38.6%, 4.8–58.2%, and 2.9–28.4%, respectively, during 2011–2012. This is the first report of parasitoids associated with M. persicae in greenhouse environments in India. The present findings suggest that the management of M. persicae could be possible with the addition of augmentative releases of these parasitoids, which should help reduce pesticide use in Indian vegetable production greenhouses.  相似文献   
10.
Foliar application of nickel (Ni) has higher use efficiencies and is preferred over soil application in view of its very low requirement. Pot experiments were conducted during winter season of 2012-2013 and repeated during 2013-2014. Treatments consisted of twelve Ni levels applied as nickel sulphate (NiSO4.7H2O) spray (T1-Ni0%, T2-Ni0.05%, T3-Ni0.1%, T4-Ni0.2%, T5-Ni0.3%, T6-Ni0.4%, T7-Ni0.5%, T8-Ni0.6%, T9-Ni0.7%, T10-Ni0.8%, T11-Ni0.9%,and T12-Ni1.0%,) with recommended doses of fertilizers (RDF) applied in all pots. The result showed that growth and yield attributes viz. plant height, leaf greenness index, number of tillers, number of ears pot-1, number of grains ear-1, straw yield, grain yield and weight of 1000 grains of barley was the maximum with three foliar application of 0.2% of NiSO4.7H2O (T4-Ni0.2%) at 20, 40, and 60 days after sowing (DAS) during both the years. The concentration of Fe, Mn and Zn in grain increased significantly up to T4-Ni0.2% and after this level, a significant decline was recorded during both the years. As regards to the concentration of Ni is concerned, it increased significantly both in grain and straw with increasing levels of Ni spray and the maximum concentration was at T12-Ni1.0%, during both the years. The uptake of Fe, Mn, Cu and Zn in grain of barley increased significantly during both the years up to T4-Ni0.2%,thereafter, it declined significantly with successive increase in dose of Ni spray. Thus 0.2% foliar spray of NiSO4.7H2O significantly increased growth, yield and Fe, Cu, Mn, Zn (micronutrients) status in barley.  相似文献   
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