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61.
Fifty-one cowpea (Vigna unguiculata (L.) Walp.) genotypes were tested by mechanical inoculation with seven geographically diverse isolates of cowpea aphid-borne mosaic potyvirus to identify resistant sources. Of 51 genotypes three, TVu-401, TVu-1582 and TVu-1593 were found immune to all the seven isolates. Forty-five genotypes gave different reactions to individual isolates. Several immune, resistant and tolerant genotypes against each isolate were identified. A considerable evidence of pathogenic variability among the virus isolates was also observed.  相似文献   
62.
The Asiatic or Himalayan black bear (Selenarctos thibetanus) is an endangered species. In South Asian countries, captive tamed Himalayan bears are commonly used by roving bear-charmers to entertain the people in rural and urban areas. In captivity, this species confronts several psychophysical traumas and communicable diseases, which are prevalent in other domestic species. The present report describes four cases of Trypanosoma evansi infection in live Himalayan charming bears, which originated from the Faisalabad and Jhang districts of Pakistan. The condition was characterized by pyrexia, accelerated pulse, tachypnea, depression, anemic mucous membranes, and ataxia (n = 3). Microscopic examination of peripheral blood films revealed moderate (n = 2) or high (n = 2) numbers of T. evansi. All four bears were treated twice at 3-day intervals with suramin sodium by using almost twice the dosage recommended for common domestic animals (10 mg/kg). The treated bears were found aparasitemic on repeat blood testing on days 5, 7, and 10 post-treatment. No adverse effects were noted and all four cases recovered in 3-7 days after completion of the second round of treatment. One bear died 8 days after the second treatment (day 11). This is the first report of T. evansi in bears.  相似文献   
63.
Growth rates of 29 multipurpose trees grown in an agroforestry arboretum for six years at a sub-humid to semi-arid climatic zone are presented. Exotic species such as Grevillea robusta, Sesbania grandiflora, Leucaena leucocephala, Cassia siamea and Sesbania sesban, some of which were outside their traditional climatic zones, had higher diameters, heights and bole volumes/tree (upto 130% more in certain cases) than of the indigenous species. However, poor performance of several species (both exotic and indigenous) would limit their agroforestry potentials at the evaluation site or other similar areas.  相似文献   
64.
Striga hermonthica (striga) weed is a major threat to crop production in sub-Saharan Africa, and short duration improved fallow species have recently been found to reduce the effects of this weed because of their ability to replenish soil nitrogen. The objective of this study was to compare the efficacy and profitability of coppicing improved fallow species (Gliricidia sepium [gliricidia], Leucaena trichandra [leucaena] and Calliandra calothyrsus [calliandra]) and non-coppicing species (Sesbania sesban [sesbania], Mucuna pruriens [mucuna], and Tephrosia vogelii [tephrosia]), in controlling striga. Natural fallow and a sole maize crop were included as control treatments. The fallow treatments were split into two and either fertilized with N or unfertilized. The results showed that coppicing fallows produced higher biomass than non-coppicing fallows. For example, Callindra (coppicing fallow species) produced 19.5 and 41.4 Mg ha−1 of leafy and woody biomass, respectively after four cumulative harvests as compared with Sesbania (non-coppicing species), which produced only 2.3 and 5.9 Mg ha−1 leaf and woody biomass, respectively. Improved fallows reduced striga population in proportion to the amount of leafy biomass incorporated into the soil (r = 0.87). N application increased cumulative maize yield by between 15–28% in improved fallow systems and by as much as 51–83% in the control treatments. Added total costs of the coppicing fallows did not differ significantly from those of the non-coppicing fallows and control treatments. However, the added net benefits of the coppicing fallows were significantly higher (US$ 527 for +N and 428 for −N subplots; P < 0.01) than those of the non-coppicing fallows (US$ 374 for +N and 278 for −N), and the least for the control treatments. The most profitable fallow system was Tephrosia with net added benefits of US$ 453.5 ha−1 season−1 without N, and US$ 586.7 ha−1 season−1 with added N.  相似文献   
65.
Radiation is considered as a promising insect pest control strategy for minimizing postharvest yield losses. Among various techniques, irradiation is a method of choice as it induces lethal biochemical or molecular changes that cause a downstream cascade of abrupt physiological abnormalities at the cellular level. In this study, we evaluated the effect of 60Co-γ radiation on various developmental stages of Zeugodacus cucurbitae Coquillett and subsequent carry-over effects on the progeny. For this purpose, we treated eggs with 30- and 50-Gy radiation doses of 60Co-γ. We found that radiation significantly affected cellular antioxidants, insect morphology, and gene expression profiles. Our results indicate that in response to various doses of irradiation reactive oxygen species, catalase, peroxidase, and superoxide dismutase activities were increased along with a significant increase in the malondialdehyde (MDA) content. We observed higher mortality rates during the pupal stage of the insects that hatched from irradiated eggs (50 Gy). Furthermore, the life span of the adults was reduced in response to 50 Gy radiation. The negative effects carried over to the next generation were marked by significantly lower fecundity in the F1 generation of the irradiation groups as compared to control. The radiation induced morphological abnormalities at the pupal, as well as the adult, stages. Furthermore, variations in the gene expression following irradiation are discussed. Taken together, our results signify the utility of 60Co-γ radiation for fruit fly postharvest management.  相似文献   
66.
The Expansin protein is known for its multifaceted roles in plant growth, especially cell walls. However, very few studies have been done so far to assess the effects of expansin genes on Cotton fibre development. The present study is a successful effort to fill this gap, where the α-EXPA1 gene transformed into a local cotton variety, Gossypium hirsutum, through Agrobacterium-mediated transformation under Gossypium hirsutum Seed coat and Fibre-specific promoter (GhSCFP). The transgenic cotton plants underwent molecular characterization and fibre trait evaluation. Our results indicated that α-EXPA1 showed an up-regulated expression during the transition phase of secondary cell wall synthesis and resulted in improving the fibre parameters, especially micronaire value. Transgenic cotton fibre also showed a finer twisting under the Scanning electron microscope (SEM) as compared to non-transgenic cotton fibre samples. The fibre production is influenced by more than nine thousand genes, and the fibre improvement cannot be just achieved through a single gene transformation. However, α-EXPA1 is one of the potential candidates for cotton fibre research as it significantly improved the cotton fibre.  相似文献   
67.
BackgroundThe commercially available Newcastle disease (ND) vaccines were developed based on Newcastle disease virus (NDV) isolates genetically divergent from field strains that can only prevent clinical disease, not shedding of virulent heterologous virus, highlighting the need to develop genotype-matched vaccinesObjectivesThis study examined the efficacy of the NDV genotype-matched vaccine, mIBS025 strain formulated in standard vaccine stabilizer, and in carboxymethyl sago starch-acid hydrogel (CMSS-AH) following vaccination via an eye drop (ED) and drinking water (DW).MethodsA challenge virus was prepared from a recent NDV isolated from ND vaccinated flock. Groups of specific-pathogen-free chickens were vaccinated with mIBS025 vaccine strain prepared in a standard vaccine stabilizer and CMSS-AH via ED and DW and then challenged with the UPM/NDV/IBS362/2016 strain.ResultsChickens vaccinated with CMSS-AH mIBS025 ED (group 2) developed the earliest and highest Hemagglutination Inhibition (HI) NDV antibody titer (8log2) followed by standard mIBS025 ED (group 3) (7log2) both conferred complete protection and drastically reduced virus shedding. By contrast, chickens vaccinated with standard mIBS025 DW (group 5) and CMSS-AH mIBS025 DW (group 4) developed low HI NDV antibody titers of 4log2 and 3log2, respectively, which correspondingly conferred only 50% and 60% protection and continuously shed the virulent virus via the oropharyngeal and cloacal routes until the end of the study at 14 dpc.ConclusionsThe efficacy of mIBS025 vaccines prepared in a standard vaccine stabilizer or CMSS-AH was affected by the vaccination routes. The groups vaccinated via ED had better protective immunity than those vaccinated via DW.  相似文献   
68.
69.
Various serological tests were used for the diagnosis of glanders in the past but still complement fixation test (CFT) is the internationally prescribed test for trading equines. A new immunoblot (IB) technique has recently been introduced to overcome the well known shortcomings of CFT i. e. a considerable number of false positive and negative results and anticomplementary effects of sera. The objective of this study was the comparative evaluation of two glanders CFT antigens commercially available at Central Veterinary Institute ofWageningen UR, Lelystad, NL (CIDC) and at c.c.pro GmbH, Oberdorla, DE (c.c.pro) in a glanders endemic area regarding specificity and sensitivity. A total of 1678 serum samples from the endemic region (Province Punjab, Pakistan) and a non-endemic area (Germany) were analysed. All sera tested positive or suspicious with CFT were analysed by the confirmatory IB to exclude CFT false positive results. Both CFT antigens showed 100% sensitivity. The use of CIDC or c.c.pro antigen resulted in specificities of 77.45% or 75.71% for sera from endemic area and 93.75% or 94.79% for sera from non-endemic areas, respectively. The results demonstrate the different performances of identical tests in different epidemiologically settings. Based on these results, the combined use of CFT and IB is highly suggestive for the serodiagnosis of glanders. Good agreement was calculated between CFT (using either c.c.pro or CIDC antigen) and immunoblot.  相似文献   
70.

The deficiency of micronutrients, particularly zinc (Zn) and boron (B) has affected vegetative growth, yield and fruit quality of sweet orange in many citrus growing areas of Pakistan. The present study was conducted in 2015 and 2016 to determine the impact of Zn and B supplementation on growth and quality of sweet orange cv. ‘Blood red’. Pre-harvest foliar application of variant Zn and B levels was done at different phenological stages of fruit growth and development, i.e., full bloom, fruit set and premature stage. Results have concluded that pre-harvest foliar application of Zn and B augmented phosphorous, Zn, B, potassium, iron, and manganese contents in leaves, particularly Zn and B content from deficient to optimal level. Moreover, the combined application of Zn and B has also significantly enhanced vegetative characters such as tree height and spread along with reproductive characters, i.e., incremented numbers of fruit, fruit weight, total soluble solids, titratable acidity and ascorbic acid contents. However, among stage comparison, outcomes depicted that foliar application of Zn and B at full bloom?+?fruit set?+?premature stage resulted in maximum production with high quality fruits.

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