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61.
Fruit characteristics of the disease-resistant bluggoe-type (ABB) cooking bananas (Musa × paradisiaca L.) ‘Saba’ and ‘Pelipita’ were compared with those of the susceptible ‘Currare’ (‘Horn’). Yields of ‘Saba’ and ‘Pelipita’ were similar to those of ‘Currare’; however, ‘Saba’ and ‘Pelipita’ yielded fewer hands with a greater number of small fruit when compared with ‘Currare’. Shoot-tip cultures of both clones were readily initiated on a modified Murashige and Skoog (MS) basal medium supplemented with N6-benzyladenine (BA) in combination with indole-3-acetic acid (IAA). Propagation cultures were initiated by splitting shoot tips along their longitudinal axis and re-culturing the individual pieces to basal medium supplemented with 5 mg l?1 BA. Transfer of axillary shoots to hormone-free medium resulted in rapid and extensive root formation. Plantlet survival after transfer to methyl bromide-treated soil exceeded 90%. Establishment in the field was achieved following procedures normally used for vegetative propagation of this crop. Trial plantings of in vitro propagated ‘Saba’ and ‘Pelipita’ were established in various provinces of Costa Rica for grower evaluation and for future comparison of growth and reproductive development with plants of these and other cultivars propagated from corms. 相似文献
62.
Summary By feeding131J mixed with a honey solution it was possible to label a colony ofLasius brunneus (LATR.) which is often a pest in buildings. Using a scintillation detector the distribution of the parts of the nest in an
infested room could be determined. This was the precondition for a directed control. That method seems to be suitable also
for a control ofMonomorium pharaonis (L.).
相似文献
63.
In the wood of trees of Abies alba Mill., which were affected by “fir–dying”, morphological and physiological alterations were examined in order to investigate the origin of the disease. In this context also the influence on the technological wood quality was considered. 相似文献
64.
Werner Schuphan 《Journal of pest science》1974,47(4):49-58
Summary Plant protection as a problem of plant quality-researchThe use of pesticides —although necessary for plant protection — gives rise to cogent criticism. This refers not only to overapplications of biocidal sprays but also to certain pesticides or herbicides themselves being rather suspect as far as their physiological and biochemical behaviour and/or their peculiar metabolism are concerned. This in turn eventually leads to rather a high accumulation of toxic residues of the pesticides or of their metabolites in food plants, the latter sometimes more toxic than the pesticide itself. Furthermore undesired alterations in plant constituents important to health may occur causing significant depressions in levels of ascorbic acid (spinach) and of carotene (carrots). Chemicals used as plantregulators such as 2,4-D and their derivates may cause a most severe detrimental effect to health (damage to the offspring) even when applied in very small concentrations ranging on nanogram-levels. Therefore the dictum of Paracelsus sola dosis facit venenum does not refer to plantregulators such as 2,4-D and related chemicals. Manifold is the propaganda pro agro- chemicals and their use by manufacturers of pesticides. But they are mostly not trustworthy, erroneous and easily to refute by significant facts. 相似文献
65.
Ohne Zusammenfassung 相似文献
66.
67.
A. Werner Omazic C. Kronqvist L. Zhongyan H. Martens K. Holtenius 《Journal of animal physiology and animal nutrition》2015,99(2):258-264
This study investigated the fate of glycerol entering the rumen, in particular whether glycerol could be absorbed across the rumen epithelium. Three non‐lactating rumen‐fistulated cows were used to calculate the overall disappearance rate of glycerol in vivo and evaluate the rate of ruminal glycerol absorption. Rumen epithelial tissues isolated from sheep were used to characterise glycerol transport properties. The rate of rumen microbial degradation of glycerol was then studied in an in vitro system under anaerobic and thermo‐regulated conditions. The results showed that glycerol can be absorbed from the rumen in significant amounts. The fractional rate of absorption of glycerol was not affected by variations in glycerol concentration in the buffer solution in the in vivo study. The glycerol absorption apparently occurred largely by passive diffusion and was probably not facilitated by carriers. Glycerol also disappeared via microbial digestion and outflow from the rumen through the omasal orifice. 相似文献
68.
Hedie A. Bustamante Alfredo R. Rodríguez Daniel E. Herzberg Marianne P. Werner 《Journal of veterinary science (Suw?n-si, Korea)》2015,16(4):405-411
Lameness is one of the most painful conditions that affects dairy cattle. This study was conducted to evaluate clinical signs and plasma concentration of several pain and stress biomarkers after oligofructose-induced lameness in dairy heifers. Lameness was induced using an oligofructose overload model in 12 non-pregnant heifers. Clinical parameters and blood samples were obtained at 48 and 24 h and at 6, 12, 24, 36 and 48 h after induction of lameness. Clinical parameters included heart rate, respiratory rate, ruminal frequency and lameness score. Plasma biomarkers included cortisol, haptoglobin, norepinephrine, beta-endorphin and substance P. Differences were observed in all parameters between control and treated heifers. The plasma concentration of biomarkers increased significantly in treated animals starting 6 h after induction of lameness, reaching maximum levels at 24 h for cortisol, 48 h for haptoglobin, 6 h for norepinephrine, 12 h for substance P and at 24 h for beta-endorphin. Overall, our results confirm that lameness associated pain induced using the oligofructose model induced changes in clinical parameters and plasma biomarkers of pain and stress in dairy heifers. 相似文献
69.
Quantitative sandwich ELISA for the determination of tropomyosin from crustaceans in foods 总被引:3,自引:0,他引:3
The ubiquitous muscle protein tropomyosin has been identified as the major shrimp allergen and is suggested to be a cross-reacting allergen. Previously, only a few methods for the detection of tropomyosin in food have been published. A quantitative sandwich enzyme-linked immunosorbent assay (ELISA) for the detection of tropomyosin from crustaceans in foods has been developed and validated. A polyclonal rabbit antitropomyosin capture antibody and the biotinylated conjugate of the same antibody for detection were the basis for the ELISA, which was specific for crustaceans. The ELISA was able to quantitate tropomyosin in various food matrixes, had a detection limit of 1 microg/g, and cross-reacted to some extent with cockroach. Recoveries ranged from 63 to 120%, and the intra and interassay coefficients of variation were <6 and <14%, respectively. 相似文献
70.
Pretzsch Hans Poschenrieder Werner Uhl Enno Brazaitis Gediminas Makrickiene Ekaterina Calama Rafael 《European Journal of Forest Research》2021,140(5):1295-1296
European Journal of Forest Research - 相似文献