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71.
Neelam Joshi Jaspal Singh Virk 《Archives Of Phytopathology And Plant Protection》2013,46(18):1815-1821
Helicoverpa armigera is a serious pest of chickpea and causes great damage to crop. Extensive and indiscriminate use of insecticides has led to the development of resistance in H. armigera. Among the several alternative methods for management of H. armigera, the nuclear polyhedrosis virus (NPV) is promising, whereas Trichoderma sp. have shown promising results against chickpea wilt. The experiments to evaluate biocontrol package against H. armigera and wilt disease under field conditions were conducted. Lowest H. armigera larval population (0.71 larvae/plant) was recorded in chemical control, which was at a par with biocontrol package (0.91 larvae/plant), and both the treatments were significantly better than control. Lowest per cent pod damage (3.85%) was recorded in chemical control followed by biocontrol treatment (5.08%) and unsprayed control (8.61%). The yields from biocontrol package (13.45 q/ha) and chemical control (15.37 q/ha) were significantly higher than unsprayed control (10.7 q/ha). There was no disease incidence in all treatments in both 2008 and 2009. 相似文献
72.
73.
Elina MS Paaso Maritta S Jaakkola Aino K Rantala Timo T Hugg Jouni JK Jaakkola 《Respiratory research》2014,15(1)
BackgroundFamily history of asthma and other allergic diseases have been linked to the risk of childhood asthma previously, but little is known about their effect on the age-of-onset and persistency of asthma until young adulthood.MethodsWe assessed the effect of the family history of asthma and allergic diseases on persistent vs. transient, and early- vs. late-onset persistent asthma in The Espoo Cohort Study 1991–2011, a population-based cohort study of 1623 subjects (follow-up rate 63.2%). The determinants were any family history (any parent or sibling); maternal; paternal; siblings only; parents only; and both siblings and parents. Analyses were conducted separately for asthma and allergic diseases while taking the other disease into account as a confounding factor. The outcomes were persistent, transient, early-onset persistent (<13 years) and late-onset persistent asthma. Adjusted risk ratios (RR) were calculated applying Poisson regression. Q-statistics were used to assess heterogeneity between RRs.ResultsFamily history was associated with the different subtypes but the magnitude of effect varied quantitatively. Any family history of asthma was a stronger determinant of persistent (adjusted RR = 2.82, 95% CI 1.99-4.00) than transient asthma (1.65, 1.03-2.65) (heterogeneity: P = 0.07) and on early-onset than late-onset persistent asthma. Also any family history of allergic diseases was a stronger determinant of persistent and early-onset asthma. The impact of paternal asthma continued to young adulthood (early-onset: 3.33, 1.57-7.06 vs. late-onset 2.04, 0.75-5.52) while the influence of maternal asthma decreased with age (Early-onset 3.94, 2.11-7.36 vs. Late-onset 0.88, 0.28-2.81). Paternal allergic diseases did not follow the pattern of paternal asthma, since they showed no association with late-onset asthma. Also the effect estimates for other subtypes were lower than in other hereditary groups (persistent 1.29, 0.75-2.22 vs. transient 1.20, 0.67-2.15 and early-onset 1.86, 0.95-3.64 vs. late-onset 0.64, 0.22-1.80).ConclusionsFamily history of asthma and allergic diseases are strong determinants of asthma, but the magnitude of effect varies according to the hereditary group so that some subtypes have a stronger hereditary component, and others may be more strongly related to environmental exposures. Our results provide useful information for assessing the prognosis of asthma based on a thorough family history. 相似文献
74.
Lucotte GL;French MS Consortium 《Genetic counseling (Geneva, Switzerland)》2002,13(2):133-138
To identify the chromosomal localizations of the multiple sclerosis (MS) genes, we conducted a genomewide linkage analysis using eighteen affected families. A MS gene is linked to markers located in the 19q13.3 region (multipoint lod-score = 2.1). Apolipoprotein E (ApoE) gene, located in this region, is an excellent candidate gene for MS because the ApoEe4 allele is acting as a severity allele in the disease. 相似文献
75.
76.
The gene for esterase (rEst1) was isolated from a new species of genus Rheinheimera by functional screening of E. coli cells transformed with the pSMART/HaeIII genomic library. E. coli cells harboring the esterase gene insert could grow and produce clear halo zones on tributyrin agar. The rEst1 ORF consisted of 1,029 bp, corresponding to 342 amino acid residues with a molecular mass of 37 kDa. The signal P program 3.0 revealed the presence of a signal peptide of 25 amino acids. Esterase activity, however, was associated with a homotrimeric form of molecular mass 95 kDa and not with the monomeric form. The deduced amino acid sequence showed only 54% sequence identity with the closest lipase from Cellvibrio japonicus strain Ueda 107. Conserved domain search and multiple sequence alignment revealed the presence of an esterase/ lipase conserved domain consisting of a GXSXG motif, HGGG motif (oxyanion hole) and HGF motif, typical of the class IV hormone sensitive lipase family. On the basis of the sequence comparison with known esterases/ lipases, REst1 represents a new esterase belonging to class IV family. The purified enzyme worked optimally at 50 degrees C and pH 8, utilized pNP esters of short chain lengths, and showed best catalytic activity with p-nitrophenyl butyrate (C?), indicating that it was an esterase. The enzyme was completely inhibited by PMSF and DEPC and showed moderate organotolerance. 相似文献
77.
Savita Alka Bhagat Pratap Kumar Pati G. S. Virk Avinash Nagpal 《In vitro cellular & developmental biology. Plant》2012,48(5):512-520
Citrus jambhiri (rough lemon) is considered a major rootstock source for a number of Citrus species. A simple method for micropropagation from nodal segments is reported. Nodal segments of C. jambhiri were inoculated on MS medium supplemented with different concentrations and combinations of 6-benzylaminopurine (BAP), kinetin, and N6-(2-isopentenyl) adenosine (2iP). Maximum multiple shoot regeneration response (75?%) was observed with BAP at 3?mg?l?1. Shoots were multiplied for 30?d on fresh medium with similar composition. A total of 67?% of the cultures showed multiplication with the optimum number of shoots (4.02) and height of shoots (1.81?cm) with BAP (3?mg?l?1) alone. Maximum rooting response (87?%) was observed with naphthaleneacetic acid at 0.5?mg?l?1. Transverse sections of shoot stems obtained in vivo (sampled from seedlings) and in vitro (regenerated from nodal segments), showed similar anatomies. Randomly amplified polymorphic DNA analysis confirmed that all the regenerated plants were genetically identical to their donor plant, suggesting absence of detectable genetic variation in the regenerated plantlets. 相似文献
78.
Balwinder Singh Sanjeev Sharma G. Rani G. S. Virk A. A. Zaidi Avinash Nagpal 《Plant biotechnology reports》2007,1(2):101-107
The aim of present investigation was to study the effect of storage conditions on percentage germination of encapsulated and
non-encapsulated somatic embryos of Kinnow mandarin (Citrus nobilis Lour × C. deliciosa Tenora). Different batches of encapsulated and non-encapsulated embryos were preserved at room temperature, 4°C, in liquid
nitrogen as such and by embedding in liquid paraffin. In the encapsulated somatic embryos stored at room temperature in sealed
Petri plates, percentage of germination was 24.99%, but 5.55% in non-encapsulated embryos after 3 days of storage. Encapsulated
embryos stored in vials containing liquid paraffin at room temperature were germinated at 18.05% after 60 days of storage,
while it was 13.88% in non-encapsulated embryos after 45 days of storage. Encapsulated somatic embryos stored at 4°C in sealed
Petri plates remained viable for up to 75 days with 6.94% germination, whereas non-encapsulated embryos remained viable for
up to 45 days with 24.99% germination. Encapsulated embryos stored at 4°C in vials filled with paraffin germinated at 11.11%
after 120 days of storage, but 5.55% in non-encapsulated embryos after 90 days of storage. Encapsulated and non-encapsulated
embryos stored in liquid nitrogen showed 58.33 and 51.38% survival, respectively, after 7 months of storage. The plantlets
developed from these embryos were transplanted after acclimatization and are growing normal. 相似文献
79.
Parker M. Pennington PhD Kira L. Marshall MS Jonnie M. Capiro MS Lauren Howard DVM Barbara S. Durrant PhD 《Zoo biology》2020,39(2):141-144
All extant species in the Rhinocerotidae family are experiencing escalating threats in the wild, making self-sustaining captive populations essential genetic reservoirs for species survival. Assisted reproductive technologies (ARTs) will become increasingly important for achieving and maintaining ex situ population sustainability and genetic diversity. Previous reports have shown that a large proportion of captive southern white rhinoceros (SWR) females are irregularly cyclic or acyclic, and that cycling females display two different estrous cycle lengths of approximately 30 or 70 days. It has been suggested that the longer estrous cycle length is infertile or subfertile, as no term pregnancies have been observed following long cycles. Here we report the achievement of two pregnancies following long luteal phases, using ovulation induction and artificial insemination with either fresh or frozen-thawed semen. One female SWR conceived on the first insemination attempt and gave birth to a live offspring. A second female conceived twice in consecutive long cycles although the first embryo was resorbed by 33 days post-insemination. A pregnancy from this female's second insemination is ongoing with expected parturition in November 2019. Whether prolonged estrous cycles in SWR are subfertile or infertile in natural breeding situations remains unclear. However, our findings demonstrate that the application of ARTs following prolonged cycles can result the successful establishment of pregnancies in SWR. Therefore, with ARTs, female SWR otherwise considered nonreproductive due to long estrous cycles may still have the potential for representation and contribution to the ex situ population. 相似文献
80.
Genotoxicity of diacetoxyscirpenol (DAS) was studied on laboratory mice after intraperitoneal injection with single and repeated
doses. DAS was administrated at three different dose levels (0.5, 0.75, and 1.0 mg/kg body weight). The study was conducted
on both somatic and germ cells additional to the sperm morphology analysis. DAS treatment resulted in a significant reduction
(P<0.01) in mitotic activity at all levels of doses tested, confirming that DAS is a potent protein and DNA synthesis inhibitor.
At somatic cells (bone marrow) both structural and numerical chromosome abnormalities were observed. Single dose treatment
showed significant abnormalities only with high dose treatment. In contrast, at repeated dose similar abnormalities were also
observed with some significance but no systematic relation between the administrated dose and abnormalities ratio could be
settled. In germ cells (testicles), structural and numerical abnormalities were also observed. In general, the frequencies
of scored abnormalities at germ cells were lower than that the somatic cells. Sperm count test revealed a decrease in the
number of released sperm after toxin treatment. Abnormalities of sperm shape (head and tail) were observed, confirming the
positive correlation between cytogenetic damage and sperm abnormality.
The results also proved that DAS is a very toxic mycotoxin, in addition to inducing chromosomal abnormalities, it causes a
severe inhibition of DNA synthesis which subsequently affects the cell cycle and cell division. A good system for good harvesting
practice and good food technology can lower the risk for the consumers. 相似文献