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1.
The present studies have shown Laurus nobilis L. to be a drought tolerant species. When the plant was first subjected to dehydration, the rate of net photosynthesis decreased from Pn = (8–10) to –1 μmol/(m2 s) and to –3 μmol/(m2 s) during the second dehydration before it was subsequently irrigated. The rewatering on August 5 and August 8 promoted a sharp burst of this parameter, but the Pn value was restored to its original level only after August 8. Soil drought caused a drop in a rate of transpiration from 65–70 to 10 mg/(m2 s). Watering soil up to a 15% moisture level brought an increase in E = 25 mg/(m2 s), but only the second watering managed to fully restore it to the initial value. Apical growth of the plants was closely correlated with soil moisture. As the soil moisture was reduced to W = 15–5%, the terminal growth reached a saturation point and started to plateau. Watering the soil up to W = 15% promoted apical growth by 4 mm. Reducing soil moisture to W = 3–4% caused a complete cessation of the growth. Subsequent watering to W = 27–28% led to a gradual and complete recovery of turgor and an increase in the growth rate up to 6–8 mm per day. The surface response functions Pn = f(I, W) and E = f(I, W) allowed us to determine conditions and levels of potential maximums and boundaries of the areas of optimum photosynthesis and transpiration: optimum Pn = 8–9 μmol/(m2 s) with I = 900–1400 μmol/(m2 s) and W = 17–24% and the optimum E = 25–35 mg/(m2 s) with I = 1000–1400 μmol/(m2 s) and W = 16–24%.  相似文献   

2.
The species composition of fungi from the genus Fusarium was studied, and the frequency of occurrence on cereals was determined. Populations of Fusarium spp. were represented by widespread species F. culmorum, F. heterosporum, F. sporotrichioides, F. oxysporum, F. nivale, F. graminearum, F. avenacеum, F. gibbosum, F. sambucinum, F. moniliforme, etc. The dynamics and frequency of occurrence of Fusarium spp. has made it possible to characterize the state of the species of fungi in a wide range of climatic areas of cereal cultivation in the Russian regions. The prevalence of the genus Fusarium was caused by the cultivars’ susceptibility to micromycetes. The frequency of occurrence of Fusarium species isolated from roots was steady, and, on the ears, it depended on the influence of weather conditions during the growing season of plants. The study of the intraspecific variability of fungi from the genus Fusarium has revealed a significant difference in signs of toxicity and pathogenicity depending on biotic and abiotic factors. More than 50% of strains from the genus Fusarium possessed low pathogenicity but had severe toxicity to wheat seedlings. Most strains of F. sporotrichiodes, F. culmorum, and F. sambucinum were highly pathogenic (from 36.4 to 55.6%) and toxic (from 55.6 to 81.3%). High adaptability to preservation in the soil and on the roots of weeds and crop residues of most crops expressing pathogenic and toxic activity was conductive to the widespread Fusarium spp.  相似文献   

3.
The aim of this study was to determine the accumulation of antioxidants at аn early stage of development of organs of P. incarnata L. plants grown in greenhouses (medicinal aromatic plants were used for comparison), as well as to evaluate the effect of biostimulant Albit. The use of amperometric and biochemical methods made it possible to measure and evaluate the total antioxidant content in aqueous extracts of leaves of aromatic plants with sedative effects compared to aqueous extracts of P. incarnata L. leaves. The latter are characterized by a lower level of antioxidant accumulation. Seed treatment with biostimulant Albit and foliar treatment of aerial parts of the P. incarnata L. plant increased the total antioxidant content and the content of carotenoids, chlorophylls a and b, and the yield of aerial parts of the plant by 10–15%. The findings suggest that the P. incarnata L. plants grown in greenhouses can be used to create antioxidant herbal remedies.  相似文献   

4.
Assessment of crop health status in real time could provide reliable and useful information for making effective and efficient management decisions regarding the appropriate time and method to control crop diseases and insect damage. In this study, hyperspectral reflectance of symptomatic and asymptomatic rice leaves infected by Pyricularia grisea Sacc, Bipolaris oryzae Shoem, Aphelenchoides besseyi Christie and Cnaphalocrocis medinalis Guen was measured in a laboratory within the 350–2?500 nm spectral region. Principal component analysis was performed to obtain the principal component spectra (PCs) of different transformations of the original spectra, including original (R), common logarithm of reciprocal (lg (1/R)), and the first derivative of original and common logarithm of reciprocal spectra (R′ and (lg (1/R))′). A probabilistic neural network classifier was applied to discriminate the symptomatic rice leaves from asymptomatic ones with the front PCs. For identifying symptomatic and asymptomatic rice leaves, the mean overall discrimination accuracies for R, lg (1/R), R′ and (lg (1/R))′ were 91.3, 93.1, 92.3 and 92%, and the mean Kappa coefficients were 0.771, 0.835, 0.829 and 0.82, respectively. To discriminate between disease and insect damage, the overall accuracies for R, lg (1/R), R′ and (lg (1/R))′ were 97.7, 98.1, 100 and 100%, and the Kappa coefficients were 0.962, 0.97, 1 and 1, respectively. These results demonstrated that hyperspectral remote sensing can discriminate between multiple diseases and the insect damage of rice leaves under laboratory conditions.  相似文献   

5.
The agronomic characteristics of different legume cover crops and their effects on soil chemical properties were investigated in a short-term field study. We compared weed biomass, nitrogen equivalence, growth rate, leaf chlorophyll content, cover crop biomass, soil total organic carbon, and soil total nitrogen under eight different legume cover crops in a short-term field experiment. We found the highest growth rate, cover crop dry biomass, N plant content, and N contribution with C. ochroleuca plants, whereas for leaf chlorophyll content, soil organic carbon, and total nitrogen the highest values were found with M. pruriens. We did not find any significant difference among C. ochroleuca and M. pruriens for cover crop dry biomass. Our findings suggest that the incorporation of cover crops into the soil can change positively the soil chemical properties, such as soil organic carbon and total nitrogen. Our results also highlight the importance of considering the short-term effect of cover crops on the tropical soil fertility maintenance, in this case, Regosol.  相似文献   

6.
In Southern China, plants are usually exposed to cold stress during winter in an unheated greenhouse, but due to the high energy consumption and costs, most of the greenhouses remain unheated. In an attempt to find a simple and affordable solution to this problem, this study was undertaken. In this research, Capsicum frutescens L. plants were studied to investigate the effect of different root zone temperatures on its growth and chlorophyll fluorescence characteristics under cold stress. The plants were cultivated under cold stress conditions in a root zone temperature (RZT) control system where the roots were subjected to four different root-zone temperature treatments of 20°C-T20, 25°C-T25, 45°C-T45 and a control CK group. Growth characteristics studied included plant height, stem diameter, plant width, root length, biomass accumulation. Whilst fluorescence characteristics investigated were chlorophyll fluorescence ratio Fv/Fm, photochemical quenching (qL), efficiency of Photosystem II (Y[II]) and electron transport rate (ETR). Chlorophyll content in the leaves of the plants was also investigated. The findings demonstrated that plants in the CK group suffered a detrimental effect on the growth characteristics registering the lowest values in the measured variables. Conversely, the highest values were observed in T25 RZT treatment. In fluorescence characteristics, values of Fv/Fm were maintained at between 0.8 and 0.83 but also suffered a photo-inhibitory depression in CK and T45 RZT treatments to Fv/Fm values of <0.79. This depicted that root zone heating protected the PS II of these plants from photoinactivation induced by cold stress. Similar trends were seen in the qL, Y[II], ETR values with the T20 and T25 treatments registering the highest values. Chlorophyll content was significantly higher in the leaves of the plants in the T20 and T25 group. The lowest chlorophyll content was recorded in the CK group. Plants in all the treatments accumulated more biomass in the shoot than in the roots as depicted by a significantly lower shoot to root ratio values with the exception of those in the CK group. The findings of this study suggest that pepper plants can successfully be grown in an unheated greenhouse in the Yangtze River Delta area of Southern China during winter by heating the root zone of the plants to a RZT value of 25°C, thereby providing a simple, affordable and cost-effective technique.  相似文献   

7.
Seven microsatellite loci were evaluated to compare the allele pool of Primorsky honeybee population (n = 90), which was introduced into the Novosibirsk region (south-western Siberia), with the populations of Middle Russian (n = 191, A.m. mellifera), Mountain Grey Caucasian (n =113, A.m. caucasica), Carniolan (n = 61, A.m. carnica) and Carpathian (n = 184, A.m. carpatica) races. The degree of genetic differentiation in Novosibirsk population using a variety of criteria (Fst, Rst (AMOVA), Nei genetic distances) was evaluated.  相似文献   

8.
Fusarium head blight (FHB) is a global problem in small-grains agriculture that results in yield losses and, more seriously, produces harmful toxins that enter the food chain. This study builds on previous research identifying within-field humidity as an important factor in infection processes by Fusarium species and its mycotoxin production. Environmental variables describing topographic control of humidity (TWI), soil texture and related moisture by electrical conductivity (ECa), and canopy humidity by density (NDVI) were explored in their relationship to the fungal infection rates, the abundance of trichothecene-producing Fusarium spp. as determined by TRI 6 gene copies and mycotoxin accumulation. Field studies were performed at four field sites in northeastern Germany in 2009 and 2011. In the wet year 2011, a high Fusarium infection rate resulted in a high abundance of trichothecene-producing fungi as well as high concentrations of mycotoxins. Simultaneously, Fusarium spp. inhibited the development of other filamentous fungi. Overall, a very heterogeneous distribution of pathogen infections and mycotoxin concentrations were displayed in each field in each landscape. The NDVI serves as an important predictor of the occurrence of phytopathogenic Fusarium fungi and their mycotoxins in a field and landscape scale. In addition, the ECa reflects the distribution of the most frequently occurring mycotoxin deoxynivalenol within the fields and landscapes. In all cases, TWI was not found to be a significant variable in the models. All in all, the results extend our knowledge about suitable indicators of FHB infection and mycotoxin production within the field.  相似文献   

9.
Biological, physical, chemical, and antigenic characteristics of a potato virus Y are investigated. Significant strain diversity of this pathogen is found in the Far East of Russia. There are ten strains affecting potato and weeds. It is shown that PVYntm strain has a remote immunochemical affinity with common PVY strain. In the Far East of Russia, the most widespread aphid vectors of this virus are Myzus percicae Sulz., Aulacorthum solani Kalt., and Aphis gossypii Glov.  相似文献   

10.
The aim of this paper is to study effects of GH and DGAT1 gene polymorphisms on feeding qualities of Hereford and Limousin bull calves bred in conditions of the Cis-Ural steppe zone. SNPs of genes GH and DGAT1 are investigated by polymerase chain reaction (PCR) and DNA restriction fragment length polymorphism (RFLP). The studied population of animals was assessed by defining the allele frequency and animal genotype occurrence for the studied gene SNPs, indicators of the actual and expected heterozygosity, and Pearson’s test. A study of polymorphism C214G of gene GH revealed that genotype LL prevails in Hereford and Limousin animals, 47.37 and 57.7%, respectively, while frequency of allele L is higher in Limousin bull calves (0.731). A study of polymorphism K232A of gene DGAT1 gene in both the populations showed absence of genotypes AA, which can be related to the low number of the studied animals. Expected heterozygosity indicators of gene GH are higher than the observed ones, and the observed heterozygosity is higher for DGAT1. The number of efficient alleles for the studied genes is higher for Hereford bull calves. In general, according to Pearson’s test, both the studied populations are in equilibrium. There is a significant effect of GH gene polymorphism on live weight gain rates at the end of sagination and total and average daily weight gains during animal raising.  相似文献   

11.
Analogs of juvenile hormones (JHAs)—azadirachtin (NeemAzal, EC (10 g/L), fenoxycarb (Phasis, WP (250 g/kg), and pyriproxyfen (Admiral, EC (100 g/L) and Inoxyfen, EC (100 g/L)—have been tested. The effectiveness of insectoacaricide NeemAzal in regulating the population numbers of sucking insects was assessed using glasshouse cucumber in Leningrad oblast. Three applications of this product in 0.5% concentration effectively protected this culture against red spider mite (Tetranychus urticae Koch.) and onion thrips (Thrips tabaci Lind) and, less significantly, against melon aphid (Aphis gossypii Glov). Insecticide Phasis protected vineyards against European vine moth (Lobesia botrana Den&Schiff). Juvenoid Admiral effectively decreased the number of imagoes and larvae of greenhouse whitefly (Trialeurodes vaporariorum Wsfw.) in glasshouse cucumber and tomato in different regions of Russia, while Inoxyfen protected apples against codling moth (Cydia pomonella). The tested products belong to the group of biorational pesticides that can be used in ecologically sound systems of plant protection.  相似文献   

12.
The results of molecular genetic analysis of wild species and varieties of genus Malus Mill. for loci of monogenic scab resistance are presented. Dominant allele of gene Rvi6 was identified in varieties of M. robusta 43199, M. hupehensis, and M. floribunda. Locus Rvi4 was detected in genotypes of M. robusta v. persicifolia, M. asiatica 2343, M. sieversii 13280, M. niedzwetzkyana 13279, M. purpurea 2392, M. orientalis 41623, M. orientalis 29476, M. orientalis 29 460, M. spectabilis v. albi plena, and M. spectabilis v. rubra plena. Gene Rvi5 in the test collection of wild species is absent.  相似文献   

13.
Genotyping for locus PGR (progesterone receptor gene) of the Holstein servicing bulls (World Wide Sires) was carried out. The frequencies of alleles and genotypes of this locus are given. Significant (P < 0.05) superiority of the homozygous genotype AA of locus PGR was found in relation to the heterozygous genotype AG for several economically valuable traits: PTAM (predicted transmitting ability for milk, 380 points), PL (productive life, by 1.3 months), and FE (feed cost–feeding efficiency index, 37 points). Significant superiority (P < 0.05) of the homozygous genotype GG over the heterozygous genotype AG for the PL trait was also found, by 1.2 months. The obtained data can be used for marker-dependent breeding.  相似文献   

14.
This paper presents history and ways of creating triploid apple cultivars differing from common diploid ones by less pronounced fruiting periodicity by years, higher marketability and weight of fruits, and self-fertility. In the search for an effective method of mass production of triploid seedlings, crosses of the type 4x × 4x, 4x × 3x, 4x × 2x, 3x × 4x, 3x × 3x, 3x × 2x, 2x × 4x, and 2x × 3x were studied. The most effective way of mass production of triploid seedlings was the 2x × 4x cross (diploid × tetraploid). In the group of 2x × 4x crosses, more than 9000 seedlings from different families were subjected to cytological analysis. The ratio of hybrid progeny in terms of ploidy levels was as follows: 30.3% diploids, 69.5% triploids, 0.2% tetraploids, and 0.04% aneuploids. It was established that triploids can also be obtained in 4x × 2x crosses; however, it is necessary to castrate the flowers in the maternal parent, since all apple tetraploids have high self-fertility. For the first time in the world, a series of triploid cultivars (approximately 20) was obtained from intervalent crosses of the diploid × tetraploid type in the All-Russia Research Institute of Fruit Crop Selection. Particularly interesting are triploid cultivars that have immunity to scab, which include nine cultivars, of which Aleksandr Boiko, Vavilovskoe, Maslovskoe, and Yablochnyi Spas are included in the State Register of breeding achievements allowed for use.  相似文献   

15.
Water chest nut Trapa is a minor fruit crop and potential carbon sequester of atmospheric carbon. Mass production of water chest nut using a vast number of unused small water bodies and derelict waters is a win-win-win-win strategy toward mitigation of global warming, nutritional security, empowerment and resource utilization. Growth performance of Trapa was conducted in small culture units using different CNP ratios (25:02:01; 101:08:01; 290:01:01) at a fixed dose (0.2 kg/tank) of mixed manure with different doses (100, 200, 400, 600 g) of optimal CNP ratio (101:08:01) during the life cycle of Trapa. The total number of fruits and the wet weight of Trapa in different dose treatments ranged from 56 to 192 and from 258 to 379 g/tank. Yield of Trapa remained maximum when CNP ratio was 101:8:1 at 200 g/tank and the dosage was 200 g/tank with the optimal CNP ratio (134 g) and then declined with further rise in fertilizer dose. The proximate analysis of Trapa revealed the highest phosphorus content in all the tissues (fruit, leaf, and root) of Trapa grown in the CNP ratio of 101:08:01. Of the total amount of carbon in Trapa, contribution was maximum by the fruit (38–41%), followed by leaf (27–35%) and root (23–32%) in different ratio treatment. The C content of harvested Trapa grown in different CNP ratios (Table 4) was higher in fruit (38–41%) followed by leaf (27–35%) and root (23–32%) among tissues. The amount of C observed in control (32%) increased by 6% in 25:02:01 (34%) which was higher than remaining two treatments (31%). Dry weight or total carbon content of water chestnut tended to rise with increasing levels of phosphate of water from the dosage of 100 to 200 g with optimal CNP ratio and declined thereafter. A direct relationship between the dry weight or carbon content of Trapa and the total carbon content or phosphate to total carbon ratio of water was established. However, the carbon content remained between 27–32% in all the three tissues of Trapa culture when cultured in different dose treatments. It is reasonable to conclude that water chestnut may be promoted for mass cultivation using the recommended culture protocol that would help trapping atmospheric carbon, provide nutritional security and employment generation and resource utilization.  相似文献   

16.
Two successive genotypings (in 2014 and 2017) of the leptin gene (LEP) by the R25C and Y7F loci were conducted in the herd of the Ayrshire cattle of the Niva Farm of Krasnodar Krai in order to study the influence of polymorphism of these loci on the duration of the economic use. DNA samples (n = 154) isolated from blood of animals with different periods of economic use have been analyzed. The need for genotyping in 2017 arose because of the ambiguous interpretation of the findings obtained in 2014. A higher frequency of occurrence of the RR genotype of the LEP in the group of long-livers could be explained both by better preservation of animals with the RR genotype and by random gene drift (in particular, by larger share of breeder bulls, the carriers of the R allele). It was found that, as in 2014, a group of long-liver cows genotyped in 2017 differed from the group of young cows genotyped in 2014 in the occurrence frequency of the RR genotype, which was doubled. Consequently, regardless of the experimental conditions, animals of this particular group may have a longer productive life. It has also been established that the polymorphism at the Y7F locus does not have a significant effect on the duration of the economic use of the Ayrshire cows.  相似文献   

17.
The complex assessment has been given to the pea varieties permitted for use by productivity and parameters of the adaptive ability based on the results of their test in three natural and climatic zones in Tyumen oblast. The best varieties by average productivity have been found—in conditions of subtaiga, Yamal’skii; in northern forest steppe, Yamal; and in southern forest steppe, Omskii 9. All varieties had strong variability of productivity. The highest level of realization of productivity potential of varieties was noticed in the conditions of subtaiga. The highest general adaptive ability was peculiar to the varieties Yamal’skii, Agrointel, and Yamal; and the largest values of a variance of the specific adaptive ability were detected in the varieties Omskii 9, Batrak, and Tyumenets. By plasticity, the varieties were divided into three groups: weakly responsive to the improvement of conditions (b i < 1)—Omskii 9 and Batrak; intensive, with high response to the improvement of conditions (b i > 1)—Yamal and Agrointel; and plastic, changing the productivity of which fully corresponds changing the growth environment (b i = 1)—Tyumenets and Yamal.  相似文献   

18.
The article presents the importance of plant genetic hybrid shift in the elements of productivity, allowing the prediction of the conduct in the selection of promising lines obtained by interspecific hybridization spontaneous soybeans for further study in the selection process. The maximum shift of genetic selection on the basis of elements of efficiency in terms of the number of marked beans in combinations Volzhan × KZ-671, KZ-Rosinka × 1236, and Luch nadezhdy × KZ-6332 in terms of the mass of 1000 seeds only in the combination Luch nadezhdy × KZ-6332.  相似文献   

19.
The results are obtained by simultaneous diagnostics of mutant CV- and BL-alleles. Five groups of animals–carriers and noncarriers of mutations are identified. In Russia the mutant CV-alleles are met more frequently because of the intensive use of their carriers. While elimination of BL-allele was started earlier due to developed methods, the diagnostics of CV-mutations has been undertaken later. Propagation of missense-mutations in the world and the Russian Federation has been occurring through the breeding bulls and cows–carriers. Initially spermobanks and, afterwards, cows were reserves for the diagnosed BLand CV-mutations.  相似文献   

20.
The results of study of the morphophysiological components of productivity in serviceberry variety samples are presented. These results revealed that the species A. canadensis, Slayt, and A. alnifolia feature a high level of morphostructural components of productivity under the conditions of the Central Black Earth zone. Intensive processes of photosynthesis take place in A. canadensis.  相似文献   

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