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101.
Summary Purple colourations of the cauliflower curd detract from the commercial value of the crop. Curds were found to develop purple colourations when in aseptic nutrient culture, and this was correlated with their inherent tendencies to form purple curds in the field as revealed by a progeny test. It was advocated that selection against the defect in the field should be supported by assessment in culture.  相似文献   
102.
    
Summary

Carrot roots from a range of environments, developmental stages and cultivars showed variation in splitting susceptibility from 3.8% to 72.5%. Estimates of tissue tensile strength, fracture toughness and residual strain for roots from these sources were not related to estimates for damage. The measurement of release of intrinsic stress from whole-root sections showed some relationship with damage in that the most susceptible cultivars also displayed greater release of stress. These same varieties had larger storage cells in their outer parenchyma. Developmental variation in tissue strength induced by different sowing dates and years was inconsistent between years. Increases in strength of root tissue with advancing date during the autumn observed in field experiments, were not related to temperature changes imposed in controlled environment. Variation in water and solute potentials was generally greater than variation in turgor potential, which remained well conserved in all experiments. Fracture toughness, which is dependent on tissue water status, was not well related to turgor in these experiments.  相似文献   
103.
Microscopic techniques were used to determine accessible regions in various starches under different swelling conditions. Fatty acyl chlorides of increasing chain length (C6–C16) were reacted with 2‐aminopyridine to produce the corresponding fatty acyl amides. Starch granules (common corn, waxy maize, potato) were treated with the series of fluorescent amides under a variety of conditions: anhydrous (hot pyridine), aqueous (no heat), and aqueous alkali (49°C, with and without swelling‐inhibiting salts). Isolated granules were then viewed by confocal laser scanning microscopy to determine reagent analog penetration. All populations of granules were heterogeneous with respect to fatty acyl amide penetration, but general patterns could be discerned. Observations also indicated that the area surrounding the hilum was more easily penetrated than was the rest of the granule matrix. No substantial differences in penetration of the fluorescent fatty acyl amides as the chain length increased (C6–C16 was observed in hot pyridine‐swollen common corn starch granules. Common corn and potato starch granules swollen in room temperature water showed cutoffs for granular exclusion at C14 and C12, respectively. Common corn, waxy maize, and potato starch granules treated under industrial etherification conditions (heat, pH ≈ 11, swelling‐inhibiting salts) were less accessible to C6, C8, and C10 fluorescent amides when sodium citrate was present than when sodium sulfate was used, and less accessible in either case than in water alone or in hot anhydrous pyridine. However, appreciable differences between inhibition by sodium sulfate and sodium citrate were not observed in every case.  相似文献   
104.
Detection of koi herpesvirus DNA in tissues of infected fish   总被引:6,自引:0,他引:6  
A newly recognized herpesvirus, koi herpesvirus or KHV, causes a lethal disease in common carp, Cyprinus carpio , and its colourful strain known as koi or fancy carp. In this study, we report new outbreaks of the disease, present initial characterization of the KHV genome, and describe assays for detection of KHV DNA in infected cells and tissues of infected fish. Restriction endonuclease (RE) profiles of viral DNA derived from two epidemiologically distinct KHV isolates were identical to each other. Cloned KHV BamHI and SphI DNA probes specifically hybridized to KHV DNA, but not to DNAs derived from a variety of other fish herpesviruses. The KHV DNA probes detected KHV DNA in tissues of experimentally infected koi fish by DNA hybridization. The KHV specific polymerase chain assays (PCR) were developed for rapid detection and confirmation of KHV DNA in tissues of infected fish.  相似文献   
105.
Microbial communities play a pivotal role in soil nutrient cycling, which is affected by nitrogen loading on soil fungi and particularly mycorrhizal fungi. In this experiment, we evaluated the effects of allochthonous nitrogen addition on soil bacteria and fungi in two geographically distinct but structurally similar scrub oak forests, one in Florida (FL) and one in New Jersey (NJ). We applied allochthonous nitrogen as aqueous NH4NO3 in three concentrations (0 kg ha−1 yr−1 (deionized water control), 35 kg ha−1 yr−1 and 70 kg ha−1 yr−1) via monthly treatments over the course of 1 yr. We applied treatments to replicated 1 m2 plots, each at the base of a reference scrub oak tree (Quercus myrtifolia in FL and Q. ilicifolia in NJ). We measured microbial community response by monitoring: bacterial and fungal biomass using substrate induced respiration, and several indicators of community composition, including colony and ectomycorrhizal morphotyping and molecular profiling using terminal restriction fragment length polymorphism (TRFLP). Bacterial colony type richness responded differently to nitrogen treatment in the different sites, but ectomycorrhizal morphotype richness was not affected by nitrogen or location. Both experimental sites were dominated by fungi, and FL consistently supported more bacterial and fungal biomass than NJ. Bacterial biomass responded to nitrogen addition, but only in FL. Fungal biomass did not respond significantly to nitrogen addition at either experimental site. The composition of the bacterial community differed between nitrogen treatments and experimental sites, while the composition of the fungal community did not. Our results imply that bacterial communities may be more sensitive than fungi to intense pulses of nitrogen in sandy soils.  相似文献   
106.
The effect of drying conditions on harpagoside (HS) retention, as well as the use of near-infrared spectroscopy (NIRS) for rapid quantification of the iridoids, HS, and 8-rho-coumaroyl harpagide (8rhoCHG) and moisture, in dried Harpagophytum procumbens (devil's claw) root was investigated. HS retention was significantly (P < 0.05) lower in sun-dried samples as compared to tunnel-dried (60 degrees C, 30% relative humidity) and freeze-dried samples. The best retention of HS was obtained at 50 degrees C when evaluating tunnel drying at dry bulb temperatures of 40, 50, and 60 degrees C and 30% relative humidity. NIRS can effectively predict moisture content with a standard error of prediction (SEP) and correlation coefficient (r) of 0.24% and 0.99, respectively. The HS and 8rhoCHG NIRS calibration models established for both iridoid glucosides can be used for screening purposes to get a semiquantitative classification of devil's claw roots (for HS: SEP = 0.236%, r = 0.64; for 8rhoCHG: SEP = 0.048%, r = 0.73).  相似文献   
107.
108.
经营公司,不是发射火箭,不需要有一点小问题就煽风点火。她是一家以蓝筹企业为客户的小型生物技术研究公司的惟一女性合伙人。她深感压力,全身心地投入。她的部下年轻、聪明而有抱负,渴望让她满意,但她从不相信他们可以独立执行任务。每个项  相似文献   
109.
D. Gray 《Potato Research》1973,16(1):80-84
Summary Single-stem plants cv.Maris Peer were grown in boxes with a tuber chamber attached so that the growth of individuol tubers could be followed. The length of the tuber-bearing stolons decreased the further they were formed from the base of the stem. Tubers formed on stolons arising from the basal nodes showed higher relative growth rates than those formed at nodes further from the base of the stem.  相似文献   
110.
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