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101.
102.
J. Jović T. Cvrković M. Mitrović S. Krnjajić Margaret G. Redinbaugh R. C. Pratt R. E. Gingery S. A. Hogenhout I. Toševski 《European journal of plant pathology / European Foundation for Plant Pathology》2007,118(1):85-89
Maize redness (MR), a disease causing midrib, leaf and stalk reddening and abnormal ear development in maize, has been reported
from Serbia, Romania and Bulgaria for 50 years. Recent epiphytotics reduced yields by 40%–90% in southern Banat, Serbia. MR
was recently associated with the presence of the stolbur phytoplasma, although the epidemiology of the disease remained unknown.
Diseased fields in southern Banat were surveyed for potential vectors of the phytoplasma during 2005 and 2006, and high populations
of Reptalus panzeri were found. In affected fields, 20% of the R. panzeri individuals and 85% of symptomatic maize plants carried the stolbur phytoplasma. When stolbur phytoplasma-infected R. panzeri were introduced into insect-free mesh cages containing healthy maize plants, midrib and leaf reddening developed on 48% of
plants and stolbur phytoplasma was detected in 90% of the symptomatic plants. No symptoms or phytoplasma-positive plants were
found in cages without insects. These data indicate that MR symptoms are associated with the stolbur phytoplasma. Reptalus panzeri is both abundant in affected fields and can transmit the stolbur phytoplasma, indicating the insect is likely to be a major
vector of MR. 相似文献
103.
104.
105.
106.
A. Yu. Kudeyarova 《Eurasian Soil Science》2010,43(6):635-650
The chemisorption mechanisms of phosphate anions by iron (aluminum) containing sorbents in a soil under high phosphate loads
were studied. The role of the metal-phosphate anions in the destruction of the sorbents was discussed. It was shown that the
chemisorption of phosphate anions and the destruction of phosphated organomineral sorbents are interrelated processes. A significant
part of the chemisorbed phosphates in association with sorbent metals and carbon passes into the liquid phase of soil systems. 相似文献
107.
Urban soils (Urbic Technosols) formed within or near the industrial sites removed of service show a considerable excess over the regional background in the content of Pb, Zn, Cu, Mn, Cr, Ni, as well as over the average content of W, Mo, Pb, Sb, Cr, Cu, Sn, Ni, Zn, and Mn in urban soils. Microelements are concentrated for the most part in the soil fine earth, and above all, in the fraction with particle size <0.1 mm. Surface films (on quartz and feldspar grains) of quartz–feldspar–muscovite (partially with tremolite and chlorite) composition and undifferentiated dispersed mixture of quartz, albite, microcline, muscovite and organomineral soil substance are the strongest concentrators of heavy metals and metalloids. Pb and Sn are partially present in soils as oxides, and a part of Zn and Pb, in the form of substantial admixtures to technogenic chemical compounds. As a whole, distribution of elements in the studied soils is controlled by the specifics and type of contamination, resistance of coarser grains to weathering under the given physicochemical conditions, and by predominantly mineral (quartz–feldspar) composition of the solids in soil layers and the features of elements proper. 相似文献
108.
Data are given on the biochemical composition of apple fruits of spontaneous and induced clones and tetraploid forms. The possibility of improving it by means of spontaneous and induced clones is shown. 相似文献
109.
An increase in the nitrogen-fixing ability of annual pulses by 1.5–2 times under the effect of inoculating seeds with Rhizotrophin
is established in 3-year field experiments. The quantitative parameters of biologically fixed nitrogen and additional grain
yield of pulse crops and spring wheat planted after them are determined.
Original Russian Text ? G.P. Gamzikov, P.R. Shott, A.P. Kozhemyakov, 2008, published in Doklady Rossiiskoi Akademii Sel’skokhozyaistvennykh
Nauk, 2008, No. 2, pp. 23–25. 相似文献
110.
M. L. Tsvetkov 《Russian Agricultural Sciences》2008,34(5):350-351
A new method of forming bee colonies has been developed and a patent is obtained for it. The method consists in a considerable
(theoretically, 100%) increase from strong highly productive colonies without their entry into a swarming state, without a
reduction of productivity, and with complete readiness for overwintering (with respect to food) of both the parent colony
itself and the newly formed one. 相似文献