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61.
The calli induction from different Sunflower necrosis virus (SNV)-infected explants of sunflower was initiated on Murashige & Skoog medium amended with benzyladenine at 1 mg l -1 and indole acetic acid at 0.5 mg l -1. The virus was purified from the induced calli by sucrose density gradient centrifugation and the viral particles were confirmed by transmission electron microscopy. The SNV infection in uninfected calli was established by a soak prick method and the viral development was confirmed by a plant infectivity test. Serological analyses such as Ouchterlony double immnuodiffusion test, enzyme-linked immunosorbent assay and Western blot using anti-SNV antibodies yielded positive reactions with the purified SNV. These investigations have demonstrated that the SNV could be cultured in calli and maintained in vitro in pure form for a long period of time.  相似文献   
62.
Where hunting pressure is high, anti-poaching efforts are often crucial for protecting native wildlife populations in nature reserves. However, many reserves suffer from inadequate support and provisioning of staff, especially in developing nations. In Pakke Tiger Reserve in northeastern India, we found that malarial infection is a serious hindrance for front-line patrolling staff that limits the time they can spend in the field. We assessed the consequences of malaria both for local people and park staff in the general region and its indirect effects on wildlife protection. To accomplish this we compiled data from annual epidemiological records of malaria, the number of malaria cases and associated mortality, financial costs, and loss of time spent patrolling. Over a 4-year period (2006–2009), the majority (71%) of forest department staff in Pakke Tiger Reserve suffered from malaria. Malaria treatments cost park managers nearly 3% of their total budget and caused a net loss of 44,160 man hours of anti-poaching effort. The government forest and health departments involved in the employment and health of park staff have separate missions and responsibilities, yet our findings show that a multi-disciplinary approach to conservation is essential to avoid overall systemic failure.  相似文献   
63.
Ultrafast electron diffraction (UED) has been developed to study transient structures in complex chemical reactions initiated with femtosecond laser pulses. This direct imaging of reactions was achieved using our third-generation apparatus equipped with an electron pulse (1.07 +/- 0.27 picoseconds) source, a charge-coupled device camera, and a mass spectrometer. Two prototypical gas-phase reactions were studied: the nonconcerted elimination reaction of a haloethane, wherein the structure of the intermediate was determined, and the ring opening of a cyclic hydrocarbon containing no heavy atoms. These results demonstrate the vastly improved sensitivity, resolution, and versatility of UED for studying ultrafast structural dynamics in complex molecular systems.  相似文献   
64.
The aim of the study is to investigate the biocontrol mechanisms of Trichothecium roseum MML003 against the rice sheath blight (ShB) pathogen, Rhizoctonia solani as the former exhibited strong antagonistic activity against the latter. It has been found that T. roseum MML003 did not show any hyperparasitic interaction against R. solani. Further, it did not produce siderophores and hydrogen cyanide. However, the culture filtrate of T. roseum MML003 strongly inhibited the mycelial growth and sclerotial formation, its germination and viability, which proved that the biocontrol activity is antibiosis-mediated. The extracellular crude antifungal metabolites of T. roseum MML003 were thermo and photo-stable. Potted plant experiment showed that the crude metabolites of T. roseum MML003 effectively reduced the ShB disease in rice up to 47.7%. Thus, this study assumes significance as it provided further scope for the identification of antifungal metabolites from T. roseum MML003 and their possible use against sheath blight disease of rice.  相似文献   
65.
Corn is widely used as animal feed as well as for fuel ethanol production. Fiber present in corn is not digested well by non-ruminants such as chicken and swine. Also, this fiber does not participate in conversion of starch to ethanol. Fiber separation from ground corn flour using the Elusieve process, a combination of sieving and elutriation (air classification) results in high starch animal feed, and in increased ethanol productivity. The objective of this study was to understand the effect of retention screen size in the hammer mill on fiber separation from corn flour using the Elusieve process. Four different retention screen opening sizes were studied; 1.4 mm (3.5/64”), 2.0 mm (5/64”), 2.8 mm (7/64”) and 3.2 mm (8/64”). Ground corn flour was sieved into size fractions and the size fractions were subjected to air classification. As the retention screen size increased, fiber separation improved, and the difference in starch content between enhanced flour and original flour increased. The highest starch content of 64.1-65.2% was in the enhanced flour from Elusieve processing of corn flour obtained by using 3.2 mm (8/64”) retention screen in the hammer mill, while the starch content of the original corn flour was 62.5%. It is expected that at some threshold retention screen size, the fiber separation using the Elusieve process would be deteriorated. This threshold retention screen size was not reached in this study.  相似文献   
66.

Background

Many Crotalaria plant species contain hepatotoxic pyrrolizidine alkaloids (such as monocrotaline) that can cause acute and chronic poisoning in cattle and other animals.

Hypothesis

Peanut oil, atropine sulfate, and antidiarrheal agents are used to treat acute monocrotaline poisoning. The effect of sesame on acute monocrotaline poisoning has never been investigated.

Animals

Fifty male Sprague‐Dawley rats were used for toxicity studies.

Methods

Experiment 1: Group I, control. Groups II–IV were given monocrotaline (205.2 mg/kg) and euthanized 6, 12, and 24 hours later. Experiment 2: Group I, control. Group II monocrotaline alone (205.2 mg/kg). Groups III–VI were given monocrotaline (205.2 mg/kg) and 1 hour later, Groups III and IV were given sesame oil (1 and 2 mL/kg) and Groups V and VI were given peanut oil (1 and 2 mL/kg).

Results

Monocrotaline significantly decreased (< .05) serum amylase activity, but, over time, increased (< .05) pancreatic and lung injury. AST and ALT activity and liver injury peaked at 24 hours. Sesame oil and peanut oil (< .05) inhibited the changes in all tested parameters in acute monocrotaline poisoning. Although peanut oil inhibited acute monocrotaline poisoning, it induced steatosis, but sesame oil did not.

Conclusion and Clinical Importance

We hypothesize that early pancreatic and lung injury and late liver injury contribute to acute monocrotaline poisoning and that sesame oil is more efficacious than peanut oil against acute monocrotaline poisoning in rats. However, additional studies are needed to confirm that these oils have the same effects in cattle and other animals.  相似文献   
67.
We examined the community composition of microbes that colonized atrazine-containing beads buried in agricultural soils that differed in atrazine treatment history. Bacterial abundance was 5-40-fold greater in atrazine-fortified beads. In beads containing 20 mg atrazine kg−1 buried in soil with a history of atrazine application (conditioned soil), the abundance of Actinobacteria increased approximately 80-fold whereas in control soil, Actinobacteria were enriched only 10-fold and the gamma-Proteobacteria and Planctomycetes increased by 60- and 25-fold, respectively. The gamma-Proteobacteria were enriched by 120- and 230-fold in beads containing 200 mg atrazine kg−1 in conditioned and control soil, respectively. The results demonstrate that BioSep® beads are a suitable matrix for recruiting a diverse subset of the bacterial community involved in atrazine degradation.  相似文献   
68.
Fusarium wilt (FW; caused by Fusarium oxysporum f. sp. ciceris) and Ascochyta blight (AB; caused by Ascochyta rabiei) are two major biotic stresses that cause significant yield losses in chickpea (Cicer arietinum L.). In order to identify the genomic regions responsible for resistance to FW and AB, 188 recombinant inbred lines derived from a cross JG 62 × ICCV 05530 were phenotyped for reaction to FW and AB under both controlled environment and field conditions. Significant variation in response to FW and AB was detected at all the locations. A genetic map comprising of 111 markers including 84 simple sequence repeats and 27 single nucleotide polymorphism (SNP) loci spanning 261.60 cM was constructed. Five quantitative trait loci (QTLs) were detected for resistance to FW with phenotypic variance explained from 6.63 to 31.55%. Of the five QTLs, three QTLs including a major QTL on CaLG02 and a minor QTL each on CaLG04 and CaLG06 were identified for resistance to race 1 of FW. For race 3, a major QTL each on CaLG02 and CaLG04 were identified. In the case of AB, one QTL for seedling resistance (SR) against ‘Hisar race’ and a minor QTL each for SR and adult plant resistance against isolate 8 of race 6 (3968) were identified. The QTLs and linked markers identified in this study can be utilized for enhancing the FW and AB resistance in elite cultivars using marker-assisted backcrossing.  相似文献   
69.
Tomato wild relatives are important sources of resistance to many pests of cultivated tomato [Solanum lycopersicum L. (syn. Lycopersicon esculentum Mill.)]. Eleven wild tomato accessions previously identified at AVRDC—The World Vegetable Center as resistant to Bemisia tabaci were evaluated for resistance to the two-spotted spider mite [Tetranychus urticae (Koch.)] based on egg numbers using the leaf disc and Tanglefoot no-choice bioassays, and damage scores in choice bioassays. Highest resistance based on choice and no-choice bioassays was identified in AVRDC S. galapagense accessions VI057400, VI045262, VI037869 and VI037239, and S. cheesmaniae accession VI037240, all of which are new sources of T. urticae resistance. In addition, S. pimpinellifolium accession VI030462 exhibited resistance only in the no-choice bioassay based on egg numbers. Resistance to T. urticae based on the number of eggs from the no-choice bioassays was positively correlated with density of type IV glandular trichomes and negatively correlated with densities of type V trichomes. All resistant accessions accumulated high levels of total acylsugars, which were positively associated with type IV trichomes. There was a significant negative relationship between acylsugar content and T. urticae egg numbers from the no-choice bioassays. There was high correlation between the results from the leaf disc test and the Tanglefoot no-choice bioassay. These findings support the possible presence of broad-based insect and mite resistance in accessions closely related to cultivated tomato.  相似文献   
70.
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