scholarly journals Species domination in oats phytocenosis and its yield

2012 ◽  
Vol 59 (2) ◽  
pp. 303-321
Author(s):  
Maria Wanic ◽  
Magdalena Jastrzębska ◽  
Marta K. Kostrzewska ◽  
Janusz Nowicki

The paper presents an analysis of oats phytocenosis (the crop and weeds) treated as a competitor group as concerns the species domination developing within it. The study covered oats cultivated on plots after potatoes (in crops rotation system with 25% share of oats) and twice after oats (75% share of oats in the rotation system) during the years 1990-2000. Simpson's species domination ratio and domination structure in the association identifying groups of: dominants, subdominants, influents and accessory species, were computed and studied. Relations between the studied phytocenosis features and weather conditions and oats yield were also determined. It was shown that quantitative relations in the assessed competitor associations were characterized by high variability between years and vegetation periods while no major differences were found between positions in the crop rotation systems. The density of spring phytocenosis during 11 years of studies increased resulting from increasing numbers of weeds appearing; during the late vegetation period they changed the density of associations slightly. In the spring, the groups competitive to the group of dominants consisted usually of the crop and <i>Thlaspi arvense</i> as well as <i>Chenopodium album</i>; with the passage of years their position strengthened. The enrichment of species in phytocenosis was represented mainly by an increase in numbers of accessory species. At the end of vegetation the importance of oats as a dominant increased significantly; during some seasons <i>Chenopodium album</i> co-dominated, however, with the passage of years the group of subdominants grew. Domination ratios for the studied competitor groups decreased with the passage of years, parallel to decrease of oats share in them. The studied features of phytocenosis showed a stronger correlation to the passage of years than the weather development. Invasiveness of weeds increased during consecutive seasons of cultivation while it showed less correlation with the density of oats. Oats yields showed a slight decreasing trend from year to year and was highly determined by the density of the entire weeds assemblage and in the spring by density and share of dominating species.

Pathogens ◽  
2020 ◽  
Vol 9 (3) ◽  
pp. 236 ◽  
Author(s):  
Annette Pfordt ◽  
Lucia Ramos Romero ◽  
Simon Schiwek ◽  
Petr Karlovsky ◽  
Andreas von Tiedemann

Fusarium species are common pathogens on maize and reduce the product quality through contamination with mycotoxins thus jeopardizing safety of both animal feed and human food products. Monitoring of Fusarium infected maize ears and stalks was conducted in Germany to determine the range of Fusarium species present in the field and to assess the impact of tillage, crop rotation, and weather conditions on the frequency of Fusarium species. From 2016 till 2018, a total of 387 infected ears and 190 stalk segments from 58 locations in Germany were collected. For each sample location, site-specific agronomic data on tillage and previous crops as well as meteorological data on precipitation, air temperature, and relative humidity during the vegetation period were recorded. The most frequent Fusarium species detected in maize ears were Fusarium graminearum, F. verticillioides and F. temperatum, whereas, F. graminearum, F. equiseti, F. culmorum, and F. temperatum were the species prevailing on maize stalks. Differences in the local species composition were found to be primarily associated with weather variations between the years and the microclimate at the different locations. The results indicate that mean temperature and precipitation in July, during flowering, has the strongest impact on the local range of Fusarium spp. on ears, whereas the incidence of Fusarium species on stalks is mostly affected by weather conditions during September. Ploughing significantly reduced the infection with F. graminearum and F. temperatum, while crop rotation exerted only minor effects.


2014 ◽  
Vol 67 (1) ◽  
pp. 55-66 ◽  
Author(s):  
Marta K. Kostrzewska ◽  
Magdalena Jastrzębska ◽  
Kinga Treder ◽  
Maria Wanic

<p>This study, lasting from 1999 to 2006, was conducted at the Research Station in Tomaszkowo, which belongs to the University of Warmia and Mazury in Olsztyn. The experiment was set up on brown rusty soil classified as good rye complex 5 in the Polish soil valuation system. The analysis comprised weeds in fields sown with pea cultivated in two four-field crop rotation systems with a different first crop: A. potato – spring barley – pea – spring barley; B. mixture of spring barley with pea – spring barley – pea – spring barley. Every year, at the 2–3 true leaf stage of pea, the species composition and density of individual weed species were determined; in addition, before harvesting the main crop, the dry matter of weeds was weighed. The results were used to analyze the constancy of weed taxa, species diversity, and the evenness and dominance indices, to determine the relationships between all biological indicators analyzed and weather conditions, and to calculate the indices of similarity, in terms of species composition, density and biomass of weeds, between the crop rotations compared.</p><p>The species richness, density and biomass of weeds in fields with field pea were not differentiated by the choice of the initial crop in a given rotation system. In the spring, the total number of identified taxa was 28 and it increased to 36 before the harvest of pea plants. <em>Chenopodium album </em>and <em>Echinochloa crus-galli</em> were the most numerous<em>.</em> <em>Chenopodium album, Echinochloa crus-galli, Sonchus arvensis</em>, <em>Fallopia convolvulus </em>and<em> Viola arvensis </em>were constant in all treatments, regardless of what the first crop in rotation was or when the observations were made.</p><p>The species diversity and the evenness and species dominance indices varied significantly between years and dates of observations. Species diversity calculated on the basis of the density of weed species was higher in the rotation with a mixture of cereals and legumes, while that calculated on the basis of weed biomass was higher in the system with potato. The similarity indices, which express the convergence of floristic composition as well as of the density and biomass of weeds growing in pea fields in the two crop rotation systems compared, were within a broad range (42–86%). The biodiversity of weed communities was more closely correlated to total precipitation than to air temperature.</p>


2016 ◽  
Vol 24 (2) ◽  
Author(s):  
V. Beliaev ◽  
T. Meinel ◽  
L. Grunwald ◽  
G. Schmidt ◽  
A. A. Bondarovich ◽  
...  

This article presents the results of crop yield in areas with different technologies of cultivation based on the network of automatic stations that provide data on climatic and soil-hydrological monitoring in the dry steppe during the vegetation period of May–September 2013–2016 . These data  on regional ecological and climatic parameters are of great interest to the ecologists, plant physiologists, and farmers working in the Kulunda Plain (Altai Territory). We compared the following options for cropping technologies: the modern system, which is the "no-till", technology without autumn tillage;the intensive technology of deep autumn tillage by plough PG-3-5 at a depth of 22–24 cm. Cultivation of crops was carried out using the following scheme of crop rotation: the modern system: 1–2–3–4 (wheat – peas – wheat – rape); the intensive system: 5/6 – 7/8 – 9/10 (fallow – wheat – wheat). We believe that the use of modern technology in these conditions is better due to exchange between the different layers of soil. When  the ordinary Soviet system , the so-called "plow sole" , was used , at a depth of 24 cm , we observed that this creates a water conductivity barrier that seems to preclude the possibility of lifting water from the lower horizons. Results of the study of infiltration of soil moisture at the depth of 30 and 60 cm  have shown in some years the advantages of the modern technology over the ordinary Soviet system: in the version with the use of modern technology we can trace better exchange between the various horizons and , probably,  moisture replenishment from the lower horizons. Differences in individual observation periods are comparatively large due to the redistribution of soil moisture, depending on the weather conditions, the crops used in the crop rotations, and cultivation techniques. Moreover, the average moisture reserves within the one meter layer did not show any significant differences during the growing seasons of 2013–2016 . In terms of soil moisture usage and productive grain yield according to the four year experiment, the application of the modern technology with crop rotation "wheat – rape – wheat – peas" was more effective than the ordinary Soviet system with crop rotation "wheat – fallow – wheat – wheat". The four-year observation period is clearly insufficient to identify the advantages of the modern system, as during this time it is impossible to significantly improve soil quality indicators, which will continue to determine its water-retaining properties and moisture accumulation.


Author(s):  
Georgiy Gulyuk ◽  
Aleksey Ivanov ◽  
Yuri Yanko

Current situation and agricultural management on the non-black earth area of Russia arebeing gradually worsen by the negative natural factors such as a significant increase of weather based climatic abnormal risks, deterioration of agro-meliorative conditions of agricultural lands because of colonization by tree and shrubbery vegetation and secondary bog formation, hidden degradation of soil fertility. When combined with functional loss of ameliorative complex and meliorative systems amortization, regional agriculture adaptation possibilities were rapidly limited. Production shortfall due no abnormal weather conditions for particular field crops was 19…48% during last five years, level of business realization of bioclimatic potential on a field was decreased by 7…12%.The complete realization of regional agricultural adaptive potential to weather based climatic changes and limitation of greenhouse gases emissions is possible on a basis of regeneration ofalll functions and aspects of ameliorative complex management. Toward this goal the coordinated actions of federal and regional management of Agricultural Complex, Scientific and Educational institutions, project foundations and managers are needed in a relation to human resources, scientific and regulatory supply. Any incomplete treatment in these fields inherent in visual negative consequences for food security and social economic development of rural areas of non-black earth zones not only at the current historical moment, but in a future also. Fundamental influence of solving of these problems deserves to scientific supply of innovative ameliorative complex, renewal of which should be based on principals of resources and energy preservation, nature management, computerization and digitalization management. During a long term research it was established that increase of average vegetation period temperature by lоСhas increased productivity of winter wheat, barley and summer wheat in average on 0,7 tons per ha, winter wheat and oat on 0,4 tons per ha, potatoes – 8,2 tons per ha, edible roots-6,4 tons per ha, cabbage 9,8 tons per ha, dry basis of herbage of multi and one age grasses–0,5 and 0,7 tons per ha. Increase of СО2 Concentration from 0,35 to 0,45% during last twenty years contributed into grow of yield in regional agriculture which can be estimated as 0,3 tons per ha per measure; searching remedy for agroclimatical risks decreasing production became drainage and irrigation systems (decrease 3…5 times);new method of reclamation of abandoned areas with transformation of biomass of tree and shrubbery vegetation into biochar makes it possible to decrease СО2 emissions up to times and get an adverse balance of СО2;secondary reclamation of lands covered by trees and shrubbery on area of 22ha used for vegetables and area of 37ha used for forage crops could supply a farmer with work and revenue sufficient for maintenance of one child what is on the major facts of population declaim in rural areas.


2020 ◽  
Vol 0 (6) ◽  
pp. 13-19
Author(s):  
Guzel Gumerova ◽  
Georgiy Gulyuk ◽  
Dmitry Kucher ◽  
Anatoly Shuravilin ◽  
Elena Piven

Data of long-term researches (2015–2018) in southern forest-steppe zone of the Republic of Bashkortostan, is justified theoretically and experimentally the mode of irrigation of potatoes on leached chernozems of unsatisfactory, satisfactory and good ameliorative condition of irrigated lands. For the growing periods of potatoes with different heat and moisture supply, the number of watering, the timing of their implementation, irrigation and irrigation norms are established. On lands with unsatisfactory meliorative state the number of irrigation depending on weather conditions of potato vegetation period varied from 0 to 3 (1.5 on average) with average irrigation norm – 990 m3/ha. With satisfactory meliorative state of lands the number of irrigation on average increased from 0 to 4 (2.3 on average) with irrigation norm – 1305 m3/ha. On lands with good meliorative state the number of irrigation was the highest – from 1 to 5 (3 on average) with average irrigation irrigation norm is 1653 m3/ha. It was noted that in the dry periods of potato vegetation the greatest number of watering was carried out (3–5 watering), and in the wet periods (2017) watering was not carried out except for the area with a good reclamation state, where only one irrigation was carried out by the norm of 550 m3/ha. Water consumption of potato was studied in dynamics as a whole during the growing season and the months of the growing season depending on weather conditions of vegetation period and land reclamation condition of irrigated lands, as well as in the control (without irrigation). The lowest total water consumption was in the area without irrigation and averaged 226.8 mm. In irrigated areas, its values increased to 319-353.4 mm. The average daily water consumption varied from 2.12 to 3.3 mm. The highest rates of potato water consumption were observed in June and July, and the lowest – in May and August. In the total water consumption of potatoes on the site without irrigation, the largest share was occupied by atmospheric precipitation and in addition to them the arrival of moisture from the soil. Irrigation water was used in irrigated areas along with precipitation, the share of which was 30.2–46.1 %.


2009 ◽  
Vol 57 (2) ◽  
pp. 119-125
Author(s):  
G. Hadi

The dry matter and moisture contents of the aboveground vegetative organs and kernels of four maize hybrids were studied in Martonvásár at five harvest dates, with four replications per hybrid. The dry matter yield per hectare of the kernels and other plant organs were investigated in order to obtain data on the optimum date of harvest for the purposes of biogas and silage production.It was found that the dry mass of the aboveground vegetative organs, both individually and in total, did not increase after silking. During the last third of the ripening period, however, a significant reduction in the dry matter content was sometimes observed as a function of the length of the vegetation period. The data suggest that, with the exception of extreme weather conditions or an extremely long vegetation period, the maximum dry matter yield could be expected to range from 22–42%, depending on the vegetation period of the variety. The harvest date should be chosen to give a kernel moisture content of above 35% for biogas production and below 35% for silage production. In this phenophase most varieties mature when the stalks are still green, so it is unlikely that transport costs can be reduced by waiting for the vegetative mass to dry.


Author(s):  
V. T. Sinegovskaya ◽  
E. T. Naumchenko

The article presents the results of comparative evaluation of the efficiency of the long-term application of mineral and organic fertilizers in the crop rotation system. It was found that the application of the mineral fertilizer system increased the value of hydrolytic acidity of the soil from 4,30 to 5,29 mg-eq per 100 g of soil, the indicator of metabolic acidity decreased from 5,2 to 4,9 pH units. By the end of the 11th rotation for both fertilizer systems, the content of mobile phosphorus increased by more than 4 times relative to the initial value, its mobility indicator – by 2,2-3,2 times compared with the control. The use of the organo-mineral system was accompanied by an increase in the content of humus by 0,35 % and a decrease in the C:N ratio from 11,2 to 8,9. The increased productivity of wheat was revealed when applying nitrogen and nitrogen-phosphorus fertilizers against the background of prolonged use of the mineral and organo-mineral fertilizer system. The change in wheat productivity by 56 % depended on the content of mineral nitrogen, mobile phosphorus, humus in the topsoil, and on the phosphate ion mobility. Soybean productivity depended on soil fertility indicators only by 24 %: the relationship between soybean productivity and the mineral forms of nitrogen and phosphorus is weak and direct, between productivity and P2O5 mobility - weak and inverse, with humus - moderate and direct.


2020 ◽  
Vol 66 (No. 9) ◽  
pp. 468-476
Author(s):  
Miroslav Jursík ◽  
Martin Kočárek ◽  
Michaela Kolářová ◽  
Lukáš Tichý

Six sunflower herbicides were tested at two application rates (1N and 2N) on three locations (with different soil types) within three years (2015–2017). Efficacy of the tested herbicides on Chenopodium album increased with an increasing cation exchange capacity (CEC) of the soil. Efficacy of pendimethalin was 95%, flurochloridone and aclonifen 94%, dimethenamid-P 72%, pethoxamid 49% and S-metolachlor 47%. All tested herbicides injured sunflower on sandy soil (Regosol) which had the lowest CEC, especially in wet conditions (phytotoxicity 27% after 1N application rate). The highest phytotoxicity was recorded after the application of dimethenamid-P (19% at 1N and 45% at 2N application rate). Main symptoms of phytotoxicity were leaf deformations and necroses and the damage of growing tips, which led to destruction of some plants. Aclonifen, pethoxamid and S-metolachlor at 1N did not injure sunflower on the soil with the highest CEC (Chernozem) in any of the experimental years. Persistence of tested herbicides was significantly longer in Fluvisol (medium CEC) compared to Regosol and Chernozem. Dimethenamid-P showed the shortest persistence in Regosol and Chernozem. The majority of herbicides was detected in the soil layer 0–5 cm in all tested soils. Vertical transport of herbicides in soil was affected by the herbicide used, soil type and weather conditions. The highest vertical transport was recorded for dimethenamid-P and pethoxamid (4, resp. 6% of applied rate) in Regosol in the growing season with high precipitation.  


2015 ◽  
Vol 103 (3) ◽  
pp. 279-292 ◽  
Author(s):  
Hong Ding ◽  
Shiqing Li ◽  
Yushu Zhang ◽  
Xiaoxia Hu ◽  
Xiangzhou Zheng ◽  
...  

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