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961.
Effects of soil drought on crop yield of 4 strains and 7 cultivars of spring triticale was investigated under field condition. The Drought Susceptibility Index (DSI) was evaluated in a two year experiment by the determination of grain loss in conditions of two soil moisture levels (drought-D and irrigated-IR). In the experiment response to drought was evaluated by different screening tests (leaf gaseous exchange, leaf water potential, chlorophyll content and fluorescence, leaf injury by drought and by simulated drought and heat temperature and water loss by excited leaf. The DSI values and the results of screening tests showed the genetic variation in the degree of drought tolerance. The values of DSI enabled the ranking of the tested triticale genotypes with respect to their drought tolerance and allow to divide them into three groups of drought susceptibility. Large differences among studied forms were observed also in changes of leaf water potential, fluorescence and leaf injury. For plants in vegetative stage of growth the tested breeding forms were easily separated into groups of different drought tolerance. Changes of ψ, Fv/Fm and LI as a screening tests were the most suitable techniques for estimation of degree of drought tolerance for triticale. Laboratory screening tests (leaf injury by simulated drought (LIDS) and high temperature (LIHT) and water loss (WL) of excited leaf conducted for nonstressed plants in most cases were significantly correlated with DSI. The statistically significant correlation between leaf water potential (ψ) was observed only with leaf fluorescence (Fv/Fm). Changes of Fv/Fm were significantly correlated with ψ, LI and LIHT for 50 °C. Index of leaf injury (LI) by soil drought were significantly correlated with Fv/Fm, LIDS (−1.0, −1.5 MPa), LIHT (45 and 50°C) and water loss (WL). The correlation coefficient between the tests LIDS and LIHT were most of the considered cases statistically significant which indicate that the mechanism of membranes injury resulted from simulated drought or high temperature were similar in triticale. Water loss (WL) of excited leaves was the most suitable test for screening drought tolerance in triticale population. Changes of gaseous exchange parameters were not useful as screening test in this research.  相似文献   
962.
In order to clarify the aetiological role of fungi in determining allergic diseases, we evaluated the correlation between the positive skin test response to fungal allergens and the presence of the same species in the upper respiratory tract in 193 patients with suspected allergic disease to fungi. The results of our study have shown that the isolation and identification of the fungal flora from the patient’s respiratory tract, in addition to the medical history, the symptomatology, and the diagnostic in vivo and in vitro, can be helpful to identify the species responsible for provoking the allergic manifestations, and can be recommended either as a supplement to the diagnosis or as a guidance in elimination treatment.  相似文献   
963.
A comparison of tests for independence in the FBI RFLP data bases   总被引:3,自引:0,他引:3  
P. J. Maiste  B. S. Weir 《Genetica》1995,96(1-2):125-138
Several tests of independence of alletic frequencies within and between loci have been compared, and it has been found that Fisher's exact test is the best test to use. When this test is applied to RFLP databases established by the FBI, paying no attention to the single-band problem, there is generally evidence for independence at one locus but not at two loci. When the test is restricted to double-banded entries in the databases; there is overall evidence for independence.  相似文献   
964.
The Wald-Wolfowitz test and the Kolmogorov-Smirnov test are two well-known tests which can be used to test for differences between two population distributions, where these distributions could differ in means, variances or shapes. This paper compares the simulated power of the Wald-Wolfowitz test to that of the Kolmogorov-Smirnov test in several situations. Differences in location only, differences in variance only, and differences in both location and variance are considered. In most cases, equal sample sizes of 10 and 20 are used.  相似文献   
965.
Several fundamental properties of discriminant variables are developed. In addition, the proportionality of the discriminant variables, canonical variables and RAO principal components is demonstrated.  相似文献   
966.
C Fuchs 《Gene》1980,10(4):371-373
Several Markov chain models (up to fourth order) have been fitted to the sequences of the seven DNAs presented in Fuchs et al. (1980). Two methods for determining the order of Markov chain are applied to the data. The two methods lead to different conclusions and we dicuss these discrepancies. When the distribution of the nucleotides in a DNA sequence is investigated, it is suggested that the study on the order of the Markov model should be supplemented with additional analysis.  相似文献   
967.
Field experiments using funnel traps were performed on a golf course to investigate the attractiveness of a floral Japanese beetle lure for adults of the garden chafer, Phyllopertha horticola, a common European turf pest. Traps baited with 10 mg of the floral lure consisting of phenylethyl propionate + eugenol + geraniol (3 : 7 : 3) captured more adult garden chafers of both sexes than non‐baited control traps. In contrast, 1,3‐dimethyl‐2,4‐(1H, 3H)‐quinazolinedione, the sex pheromone of the closely related pale‐brown chafer P. diversa, neither influenced alone nor in combination with the floral lure the behaviour of adult garden chafers. The results suggest that the floral Japanese beetle lure might be used for monitoring or control of P. horticola.  相似文献   
968.
The neuropharmacological profile of 4-phenyl-1-[4-(2-naphtalimido)butyl]-piperazine (PNBP), a compound that possesses a high affinity for the serotonin receptors of 1A-type (5-HT1A) and lacks an anxiolytic action, has been studied. Intracerebral administration of PNBP to rats through implanted cannulae into the hippocampal region resulted in no substantial behavioral changes during “open field” and “conflict situation” tests, as compared with those of control animals. At the same time, the behavioral effects of intraperitoneal administration of 10 mg/kg buspirone were completely abolished if buspirone had been jointly administered with 10 mg/kg PNBP. Moreover, combined application of 0.3 mg/kg PNBP and 0.3 mg/kg 8-OH-DPAT, an agonist of 5-HT1A receptors, almost completely abolished the components of “serotonin syndrome” (prone position and stamping of the forepaws) in animals under study. These findings allowed us to conclude that PNBP has the properties of a competitive antagonist of buspirone and 8-OH-DPAT.  相似文献   
969.
970.
In this paper two nonparametric tests are given for testing the nullhypothesis of parallelity of response curves in r samples. The first procedure is done by a permutation test, whose practical applicability is ensured by a FORTRAN-subroutine available from the author. As the computational work and time grows rapidly with sample sizes, a Monte-Carlo-solution is optionally given by the same procedure. Alternatively an asymptotically distribution-free test based on quadratic forms is constructed for large sample situations.  相似文献   
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