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991.
Eurasian Soil Science - The article presents the results of studying the spores and pollen preservation in soils of the permafrost zone in Yakutia (Kolyma Lowland, Bykovsky Peninsula, Yakutsk and... 相似文献
992.
A. Yu. Avdeyev O. P. Kigashpaeva Yu. I. Avdeyev L. M. Ivanova 《Russian Agricultural Sciences》2014,40(2):96-99
The results of study of spontaneous fruit size and shape mutants and inheritance of these traits in tomato are given and genetic processes are explained. It is concluded that the diversity of tomato fruit shape and weight in the collection is due mainly to mutations of genes—diameter of fruit width and diameter of height joined into an ovate cluster. 相似文献
993.
994.
N. A. Saveljeva E. E. Belova D. A. Korotchenkov O. S. Mishina A. A. Kolontsov 《Russian Agricultural Sciences》2014,40(4):242-243
The treatment of buckwheat with biostimulants Floravit E and Atonic Plus in dilutions 10?2–10?3 and 3 × 10?2, accordingly, had no effect on the stability and development of plants, as one can judge by the fluctuating asymmetry of metrical and meristic traits. Treatment with Atonic Plus led to a reduction of fluctuating asymmetry when control plants had a high value of asymmetry. Floravit E in the dilution 10?1 caused an increase of fluctuating asymmetry of half leaf width. The same effect was observed when growing buck-wheat in a lead-contaminated soil. 相似文献
995.
A. S. Timoshchenko V. F. Semikhov L. O. Nurminskaya P. N. Kharchenko 《Russian Agricultural Sciences》2014,40(1):1-4
During 1–7-day stages of ontogenesis (for example, in winter rye), biochemical changes in the aerial part of perennial grasses with adaptive Triticum-type proteins in the process of entering into the state of anabiosis were studied. It was shown that, at this point, biomass of the aerial part of plant was much higher than of the root system, and it accumulated raffinose, sucrose, glucose, and half-cystine. Synthesis of raffinose and accumulation of half-cystine continued until the stabilization of negative temperatures; as for sucrose and glucose, it ceased upon reaching the average temperature of the physiological zero, then the content of half-cystine and raffinose increased sharply, and the content of sucrose and glucose decreased at the same time. In the aerial parts of plants, fructose and phenylalanine were found, and their content increased upon reaching freezing temperatures. It was concluded that the polymerization of water-soluble proteins occurred in perennial grasses in a state of anabiosis. These proteins, along with raffinose, serve as cryoprotectants; sucrose and glucose are substrates for respiration; fructose is a substrate for respiration and protective metabolite; and phenylalanine is a substrate for the future synthesis of antioxidants. 相似文献
996.
Influence of complex compost on the agronomical properties of soil, winter wheat development and productivity, and quality of production in the conditions of a farm located in the Leningrad area of Krasnodar territory was considered. The positive action of the complex compost on these indicators was noted. 相似文献
997.
O. I. Mamykova 《Russian Agricultural Sciences》2014,40(4):291-294
It has been established that the therapeutic efficacy of anthelmintic agents (fenbendazole, Nilverm) in combination with Ribotan depends on the dose of the immunomodulator. Administration of Ribotan in a dose of 0.05 mL/kg of body weight increased nonspecific resistance to invasion and enhanced the anthelmintic action of fenbendazole and Nilverm. Ribotan in a dose of 0.5 mL/mg has a negative effect on the result of specific treatment of mice infected by Aspiculuris tetraptera. 相似文献
998.
Features of the analyzed allele distribution in domestic and foreign varieties are revealed on the basis of apple variety and shape polymorphism in alleles of genes associated with shelf life (Md-ACS1 and Md-ACO1) and fruit quality (MD-Exp7). Two allelic states have been revealed for the Md-ACS1 gene. With regard to the foreign selection Fuji and Gala varieties, the Md-ACS1 gene is in a homozygous state. In the examined varieties, the Md-ACO1 gene is represented by two allelic variants, and the MD-Exp7 gene of expansin biosynthesis is represented by three allelic forms. Allele 1 is responsible for a lowered level of expansin synthesis and is identified in wild apple-tree species (Chinese Golden Apple, Tayozhnoye, Caucasian Self-Fruitful). 相似文献
999.
This study is about relationships between total extractive contents, heartwood colour and light-induced discolourations of the tropical species African Padauk (Pterocarpus soyauxii Taub) and Jatoba (Hymenaea courbaril L.). Wood surface colour was measured spectrophotometrically before and after light irradiation. Subsequently, the total extractive content was determined and linked to the colour parameters. Total extractive content varied between 6 % (Jatoba) and 27 % (African Padauk). The fact that non-irradiated Jatoba appeared lighter and more yellow with higher extractives contents, opposed the often assumed relationship that more heartwood extractives cause darker wood. For light-irradiated Jatoba wood only the reddishness was more intense when samples had higher extractive content. In contrast, light-irradiated African Padauk showed significant differences in all colour parameters as extractives varied. High overall colour change in African Padauk due to light irradiation was observed; however, no relationship with the extractive content existed. In contrast, discolouration rate of Jatoba wood strongly varied with its extractive content. Individual wood species react differently during exposure to light and therefore require specific surface treatment to maintain the desired colour appearance and colour stability. 相似文献
1000.
基于样地调查和室内分析,比较研究了长白山地区典型的8种森林类型土壤有机碳和全氮的质量分数、碳氮比、碳密度和氮密度的分布特征。结果表明,8种林型土壤有机碳和全氮的质量分数变化范围分别是36.99~70.33、3.14~6.04 g· kg-1,有机碳、全氮质量分数最大的林型均是阔叶混交天然林。红松天然林土壤C /N值最大为15.56,其它C /N值变化范围为10.55~12.19。在土壤垂直剖面上,随着土层深度的增加,土壤的有机碳、全氮质量分数随之递减,土壤密度随之递增。8种林型土壤碳密度是杨树天然林最大,为22.13 kg· m-2,氮密度是落叶松人工林最大,为1.97 kg· m-2;针阔混交人工林的碳密度和氮密度均为最小,分别是12.37、1.11 kg· m-2。 相似文献