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31.
32.
The insecticidal activities of the extracts, fractions, and pure compound of Sterculia foetida (L.) seeds were investigated against three major stored product pests, namely, Sitophilus oryzae (L.), Callosobruchus chinensis (L.), and Tribolium castaneum (H.), through contact and fumigation bioassay. Responses varied with test chemicals, insect species, exposure times, and doses individually. The biologically active constituent of the S. foetida seeds was characterized as a cyclopropene fatty acid structurally elucidated as (2n-octylcycloprop-1-enyl)-octanoic acid (I) by spectroscopic analysis. The filter paper application of, (2n-octylcycloprop-1-enyl)-octanoic acid (I) at 0.2 mg/cm2 caused 100% mortality to all test insects 2 days after treatment (2 DAT). Among the chromatographic fractions, only the pure hexane-eluted fraction caused 100% mortality at 0.3 mg/cm2 to S. oryzae and C. chinensis 2 DAT, while the dose required to obtain the same percentage of mortality with the crude seed extract was 0.6 mg/cm2. Under all treatment conditions, T. castaneum exhibited less susceptibility, taking longer than the other insects to show symptoms of toxicity. In terms of fumigant activity, the compounds appeared to be more effective in a vapor form against all the three insects in closed containers compared with open containers. These results suggest that the insecticidal activities of the test compounds were attributable to contact mode of action, although there was also significant fumigant toxicity. The results indicate that the bioactive compound isolated from S. foetida could act as a potent insecticide against S. oryzae, C. chinensis, and T. castaneum populations.  相似文献   
33.
Regions within the mitochondrial gene encoding for the nicotinamide dehydrogenase subunit 4 (nad4) were characterized to evaluate the extent of genetic variation within and among Xiphinema diversicaudatum and Xiphinema simile populations. Four different sequence variants of nad4 were determined among eight populations of X. diversicaudatum and three variants among three populations of X. simile. Nucleotide variation was detected in 28 of 411 bp (2.43 to 4.87 %) in X. diversicaudatum and in three of 395 bp (0.25 to 0.76 %) in X. simile. This represents the first study based on the characterization of the nad4 gene for the analysis of population genetic of two Xiphinema species.  相似文献   
34.
Journal of Crop Science and Biotechnology - India has a diverse range of agro-ecological conditions which support the cultivation of different rice varieties differing in the adaptation which is so...  相似文献   
35.
We examine the impact of differences in state‐level higher education policies on location choices of undocumented immigrants in the U.S. using six years of available data over the period 2000 to 2012. The effect of greater access to higher education on the percentage of undocumented migrants residing in a state is positive, suggesting the existence of a “higher public education magnet” effect. Among states with favorable higher education policies, undocumented migrants prefer those states with larger networks, despite the likelihood of greater competition for admission to public institutions of higher education. However, undocumented migrants are reluctant to locate in states that have both large networks and unfavorable educational policies. This is possibly because the fear of attracting additional restrictive regulations dominates the positive cost‐saving effect of large networks.  相似文献   
36.
The aim of the present study was to evaluate the status of apoptosis in peripheral blood leukocytes of dogs with demodicosis. A total of 26 dogs suffering from demodicosis, and positive for Demodex canis mites by skin scraping, participated in the study, 13 with localized demodicosis (LD) and 13 with generalized demodicosis (GD). A further 13 clinically healthy dogs, all of whom were negative for mites upon skin scraping, were used as controls. The dogs with GD revealed significantly higher (P ≤ 0.0001) percentage of leukocytes with externalization of phosphatidylserine (PS) and depolarized mitochondrial membrane potentials (ΔΨm) as compared with the dogs with LD and healthy controls. These dogs also revealed significantly lower values (P ≤ 0.0001) of hematological parameters viz. hemoglobin, total erythrocytes count total leukocytes count, lymphocytes, monocytes and neutrophils. Significantly higher (P ≤ 0.0001) percentages of leukocytes with externalization of PS and depolarized ΔΨm were also found in dogs with LD as compared with the healthy controls. These dogs also revealed significantly lower values of Hb (P ≤ 0.0001), TEC (P=0.025), TLC (P ≤ 0.0001), lymphocytes (P=0.008), monocytes (P ≤ 0.0001) and neutrophils (P=0.03). It is concluded that premature apoptosis of PBL may be implicated in the immunosuppression of the dogs with demodicosis.  相似文献   
37.
The organophosphorus insecticide, chlorpyrifos, has been widely applied in agriculture; in veterinary, against household pests; and in subterranean termite control. Due to its slow rate of degradation in soil, it can persist for extended periods in soil with a significant threat to environment and public health. The mixed and pure fungi were isolated from three soils by enrichment technique. The enriched mixed fungal cultures were capable of biodegrading chlorpyrifos (300 mg L−1) when cultivated in Czapek Dox medium. The identified pure fungal strain, Acremonium sp., utilized chlorpyrifos as a source of carbon and nitrogen. The highest chlorpyrifos degradation (83.9%) by Acremonium sp. strain GFRC-1 was found when cultivated in the nutrient medium with full nutrients. Desdiethyl chlorpyrifos was detected as a major biodegradation product of chlorpyrifos. The isolated fungal strain will be used for developing bioremediation strategy for chlorpyrifos-polluted soils.  相似文献   
38.
The effect of consumption of finger millet based diets on hyperglycemiawas studied in 6 noninsulin dependent diabetes mellitus (NIDDM) subjects.All the experimental diets were planned to be isocaloric and also tocontain 75 g equivalent of carbohydrate load so that glycemic responsecould be compared with a 75 g glucose load. The glycemic response tobreakfast items compared to that of glucose was determined by comparingthe areas under the 2 hr glucose response curve. Consumption of fingermillet based diets resulted in significantly lower plasma glucose levels,mean peak rise, and area under curve which might have been due to thehigher fiber content of finger millet compared to rice and wheat. Thelower glycemic response of whole finger millet based diets may also havebeen due to the presence of antinutritional factors in whole finger milletflour which are known to reduce starch digestibility and absorption.  相似文献   
39.
To study the supplementary effect of Spirulina, pregnant rats were fed 5 different kinds of diets (casein, Spirulina, wheat gluten, Spirulina + wheat gluten, Spirulina-without additional vitamins and minerals), each providing 22% protein during the period of pregnancy. The outcome of pregnancy was assessed from litter and dams' weight and litter size. Maternal weight gain was found to be maximum with Spirulina + wheat gluten and least with the wheat gluten diet. Rats receiving Spirulina containing diets produced significantly (p<0.05) higher litter size than those receiving casein and wheat gluten. In spite of having higher litter size, Spirulina containing diet groups produced pups with birth weights comparable to those of casein. Spirulina appears to be a good dietary supplement during pregnancy.  相似文献   
40.
Apple scar skin viroid (ASSVd) infection is a major limitation to apple fruit quality and causes huge economic losses. In surveys of apple orchards in the northern Indian state of Himachal Pradesh, fruits with dappling symptoms were noticed. ASSVd was detected from these fruits and molecularly characterized. Ten clones from three isolates were sequenced, of which seven were new sequence variants of ASSVd. The clones had significant sequence variability (94–100%) with each other. Variability was more common in the pathogenic domain of the viroid genome. Four of the clones were 330 nucleotides (nt) long, and the other six had an additional nucleotide. Phylogenetic analysis showed close affinity of the present isolates with some Chinese and Korean isolates. The study reports seven new variants of ASSVd and also provides the first molecular evidence of viroid infection (ASSVd) in apple in India.  相似文献   
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