PHOTOSYNTHETIC PRODUCTIVITY OF WHEAT UNDER PHOTOCULTURE CONDITIONS SIMULATING THE LIGHT-TEMPERATURE REGIME OF THE CULTIVATION REGION

1970 ◽  
pp. 8-12
Author(s):  
N. А. Surin ◽  
А. G. Lipshin ◽  
L. V. Plekhanova ◽  
А. А. Tikhomirov ◽  
V. V. Velichko ◽  
...  
Keyword(s):  
Plant Biomass ◽  
Photosynthetic Apparatus ◽  
Growing Season ◽  
Convincing Evidence ◽  
The State ◽  
Limiting Factors ◽  
Comparative Characteristic ◽  
Limiting Factor ◽  
Potential Productivity ◽  
Photosynthetic Productivity

The aim of the research was to find out the potential production characteristics of the Krasnoyarsk 12 variety wheat plants under light culture controlled conditions, as close as possible to the average light-temperature conditions of zoning (the experimental farm "Minino" of the Krasnoyarsk Territory), which in the future will allow us to determine the limiting environmental factors that affect the shortage of the crop and the decrease in its quality in the selected cultivation regions. To achieve this goal, wheat was grown by hydroponics on expanded clay under controlled environmental conditions at the intensity of photosynthetic radiation (PAR) (690±70) mmol/m2 s and at the photoperiod of 17 hours of light and 7 hours of darkness. To assess the state of plants at different stages of growth and development, we analyzed the morphometric characteristics of plants, the indicators of the state of the photosynthetic apparatus of leaves of all tiers of the main shoot of plants, plant biomass in different growth periods, indicators of CO2-gas exchange of canopies. A comparative characteristic of the yields of wheat plants of the variety Krasnoyarsk 12, grown in the conditions of light culture and in the fields of the experimental farm "MININO" in 2020, was carried out. It was established that the limiting factor of increasing the productivity of the variety in the field appeared to be the accelerated passage of individual interphase periods and the growing season as a whole in comparison with light culture. A longer growing season in light culture was primarily associated with a longer passage of the tillering phase, during which the primary tubercles were differentiated and the ear was laid. The obtained results of growing wheat plants in light culture more fully revealed the potential limits of productivity of the variety Krasnoyarsk 12. Those results were convincing evidence that the bioclimatic resources of the experimental farm "Minino" of the Krasnoyarsk Territory did not allow realizing the potential productivity of the variety and at the same time indicated the possibility of reducing the effects of limiting factors aimed at its implementation in production conditions.

scholarly journals Growth and development of soybean varieties of the northern ecotype depending on the influence of limiting factors of the growing season

2020 ◽  
pp. 4-9
Author(s):  
Marina Evgenievna Belyshkina ◽  
Tamara Petrovna Kobozeva ◽  
Elena Vasilevna Gureyeva
Keyword(s):  
Growth And Development ◽  
Growing Season ◽  
Vegetation Period ◽  
Limiting Factors ◽  
Limiting Factor ◽  
Temperature And Precipitation ◽  
Average Annual Temperature ◽  
Favorable Conditions ◽  
Heat And Moisture

Based on long-term data, the article considers the peculiarities of growth and development of soybean varieties of the Northern ecotype depending on the conditions of the growing season and the influence of limiting factors. The need of soy plants for heat and moisture increases from seed germination to germination, then to the phases of flowering and bean formation, while their uniform distribution is important. In the absence of abnormal periods of drought or waterlogging, soybean varieties of the Northern ecotype Mature in August – early September. The purpose of the research was to determine the degree of influence of variability of agrometeorological conditions of the vegetation period in different years on the production process of soybean varieties of the Northern ecotype and to assess the possibility of their cultivation in the Ryazan and other regions of the Central district of the Non-Chernozem zone. The experiments were carried out in 2009–2019 years with varieties of soya of Northern ecotype Mahewa, Bright and the Whale. The limiting factor in some years of research in the conditions of the Ryazan region was the lack of moisture, while the biological minimum temperatures were maintained at all stages of growth and development. As a result of the analysis of the average annual temperature and precipitation data, the most favorable conditions for the cultivation of all the studied soybean varieties for seeds are formed in the Bryansk, Oryol and Ryazan regions. For Vladimir, Ivanovo, Kaluga, Moscow, Smolensk and Tula regions, the varieties Kasatka and Mageva are recommended, for Kostroma, Tver, and Yaroslavl – Kasatka. In all areas of the Central region of the Non-Chernozem zone, these varieties can be used to obtain green mass, silage and haylage.

scholarly journals Herbivory and Competing Vegetation Interact as Site Limiting Factors in Maritime Forest Restoration

Forests ◽  
2019 ◽  
Vol 10 (11) ◽  
pp. 950 ◽  
Author(s):  
Emily C. Thyroff ◽  
Owen T. Burney ◽  
Douglass F. Jacobs
Keyword(s):  
Forest Restoration ◽  
Seedling Survival ◽  
Growing Season ◽  
Limiting Factors ◽  
Limiting Factor ◽  
Significant Treatment ◽  
Vegetation Control ◽  
Competing Vegetation ◽  
Live Oak ◽  
Maritime Forest

Herbivory and competition during the regeneration phase influence forest successional dynamics. We demonstrated the importance of using the Target Plant Concept to identify and overcome site limiting factors for subtropical maritime forest restoration associated with deer browsing and competition. Quercus virginiana Mill. (live oak) bareroot seedlings were planted into clearcuts along the US Southern Atlantic coast with different treatment combinations of herbivory control (fenced or non-fenced) against white-tailed deer (Odocoileus virginianus Zimm.) browsing and competing vegetation removal (none, one-year, or two-years). After three growing seasons, mean seedling survival was 61% with no significant treatment differences. Control of browse and vegetation interacted to facilitate growth of live oak; seedlings were significantly larger for all response parameters (diameter, height, crown width) when fenced and treated with vegetation control. Removal of vegetation improved seedling performance only in fenced plots, however, indicating a shift in pressure from herbivory to competition as the most limiting site factor when deer were excluded. After the second growing season, foliar nitrogen was greater in fenced plots than non-fenced plots and greater in two-year vegetation control subplots than non-vegetation control subplots. This result, however, was absent after the third growing season. Three years after clearcutting, there was no evidence of Q. virginiana natural regeneration in non-fenced plots. Even with artificial regeneration in non-fenced plots, Q. virginiana growth was slow, indicating that herbivory was a key limiting factor. Our findings illustrate the importance of accounting for site limiting factors and may aid in developing management prescriptions to promote semi-evergreen oak regeneration in ecosystems with high pressure from herbivory and competing vegetation.

Селекция и семеноводство картофеля в Камчатском крае

2018 ◽  
Author(s):  
N.I. Ryakhovskaya ◽  
T.P. Sherstyukova ◽  
M.L. Gamolina
Keyword(s):  
Russian Federation ◽  
Potato Yield ◽  
The State ◽  
Limiting Factors ◽  
State Register ◽  
Region Selection ◽  
New Varieties ◽  
The Russian Federation ◽  
Selection Of

Рассмотрены агроклиматические условия Камчатского края и лимитирующие факторы, сдерживающие рост урожайности картофеля. Приведены характеристики новых сортов картофеля селекции Камчатского НИИСХ созданных в соответствии с приоритетными для региона направлениями селекции, включенных в Государственный реестр селекционных достижений РФ и охраняемых патентами.Agroclimatic conditions of the Kamchatka Krai and limiting factors that restrain the growth of potato yield are considered. The characteristics of new varieties of potatoes of the selection of the Kamchatsky RIA are created in accordance with the priority for the region selection areas included in the State Register of Selection Achievements of the Russian Federation and protected by patents.

CULTIVATION TECHNOLOGY ELEMENTS INFLUENCE ON NEW SPRING BARLEY BREWING VARIETIES YIELDS

1970 ◽  
pp. 21-25
Author(s):  
O. A. Artyukhova ◽  
O. V. Gladysheva ◽  
V. A. Svirina
Keyword(s):  
Growth And Development ◽  
Spring Barley ◽  
Photosynthetic Apparatus ◽  
Growing Season ◽  
Biological Indicators ◽  
Mineral Fertilizers ◽  
Mass Growth ◽  
Green Mass ◽  
Yield Structure ◽  
Cultivation Technology

The effect of applying various norms of mineral fertilizers on the biological indicators of crop plants during their growth and development in the Central non-black earth region in 2017-2019 was studied on the varieties of spring barley Vladimir, Reliable and Yaromir.such indicators as plant height, photosynthetic apparatus area, green mass growth, and elements of the yield structure were Studied. It was revealed that on average during the growing season, when the norms of mineral fertilizers were increased, the area of leaf plates increased and, as a result, the increase in green mass growth relative to the control variants increased by 56.3 % at (NРК)30, 82.3 % at (NРК)60, and 126.7 % at (NРК)90. The introduction of mineral fertilizers also influenced the formation of the crop structure. There was an increase in the tillering coefficient of varieties by 15.7%, 5.7 % and 21.3 % (Vladimir, Reliable and Yaromir, respectively) relative to the control, an increase in the number of grains in the ear from 15.1 to 22.4 PCs., the weight of 1000 grains from 48.0 to 55.7 g. and the weight of grain per ear from 0.7 to 1.2 g. There was a strong correlation between the doses of mineral fertilizers and the grain yield from + 0.80 to +1.0, and the variability was calculated.      

STRUCTURAL AND LOGIC DIAGRAM OF RESEARCH ON THE MILITARY-ECONOMIC SUBSTANTIATION OF THE RATIONAL NUMBER OF ARMED FORCES OF UKRAINE IN THE PROCESS OF FORMING THE PROGRAM OF THEIR DEVELOPMENT

2019 ◽  
Vol 2 (12) ◽  
pp. 102-110
Author(s):  
V. Nazarkin ◽  
O. Semenenko ◽  
A. Efimenko ◽  
V. Ivanov
Keyword(s):  
Rational Number ◽  
Armed Forces ◽  
The State ◽  
Limiting Factors ◽  
Development Programs ◽  
Power Structures ◽  
Scientific Substantiation ◽  
Conducting Research ◽  
Excess Number ◽  
The Military

The task of choosing the rational number of power structures is always one of the main priorities of any political leadership of the state. An insufficient number of armed forces is a threat to the national security of the state; an excess number creates pressures on the development of the country's national economy. Today, when the development programs of the Armed Forces of Ukraine are being formed in the context of the practical application of their units and subunits to carry out combat missions, questions of choosing a priority approach to the formation (justification) of the rational size of the Armed Forces of Ukraine is an urgent issue. The article proposes a structure for conducting research on the development and implementation of the methodology of military-economic substantiation of the rational strength of the Armed Forces of Ukraine in the system of defense planning of Ukraine in the formation of programs for their development for the medium and long term. The main objectives of this methodology are: scientific substantiation of the range of the necessary strength of the Armed Forces of Ukraine for the period of the program of their development; the choice of the indicator of the rational size of the Armed Forces of Ukraine according to the years of the program from a certain range of its changes; military-economic substantiation of this number under the influence of various limiting factors. The development and implementation of such a methodology will increase the efficiency of the formation and implementation of development programs of the Armed Forces of Ukraine, as well as the efficiency of using public funds for the development of power structures.

Mechanisms of Impairment of the Photosynthetic Apparatus in Intact Leaves by Ozone

1999 ◽  
Vol 54 (9-10) ◽  
pp. 824-829 ◽  
Author(s):  
Thomas Gerhard Reichenauer ◽  
Harald Romuald Bolhàr-Nordenkampf
Keyword(s):  
Plant Growth ◽  
Calvin Cycle ◽  
Photosynthetic Apparatus ◽  
Net Photosynthesis ◽  
Major Effect ◽  
Photochemical Reactions ◽  
Early Event ◽  
Lag Phase ◽  
Limiting Factor ◽  
Negative Consequences

Tropospheric ozone has been recognised as a limiting factor for plant growth since late fifties of our century. The decrease in the rate of light saturated net photosynthesis (Asat) was shown to be the major effect of ozone in leaves with negative consequences for plant growth and the development of plant communities. The reasons for the ozone-induced decrease in Asat are still under investigation. Possible mechanisms are an increasing stomatal limitation, an increase in mesophyll limitation including a reduction of the CO2 fixation in the Calvin cycle and an impairment of the photochemical reactions in the grana membranes of chloroplasts. We conclude from the reviewed literature and from our own experiments that a decrease in carboxylation efficiency (CE) seems to be an early event caused by ozone leading to a decrease in Asat. The loss in current photochemical capacity (Fv/Fm) appears with a lag phase of many days and therefore the loss is thought to be a secondary effect due to a decreased demand of ‘assimilatory power’

No evidence for interspecific interactions between plants in the first stage of succession on coastal dunes in subarctic Quebec, Canada

1997 ◽  
Vol 75 (6) ◽  
pp. 902-915 ◽  
Author(s):  
Gilles Houle
Keyword(s):  
Plant Biomass ◽  
Interspecific Interactions ◽  
Regional Climate ◽  
Salt Spray ◽  
Coastal Dunes ◽  
Growing Season ◽  
Coastal Dune ◽  
Dune System ◽  
Abiotic Conditions ◽  
Herbaceous Perennials

Coastal dunes are very dynamic systems, particularly where the coast is rising as a result of isostatic rebound. In those environments, succession proceeds from plants highly tolerant to sand accumulation, salt spray, and low nutrient availability to less disturbance-tolerant and stress-tolerant, more nutrient-demanding, and supposedly more competitive species. In the subarctic, the regional climate exacerbates the stresses imposed by local abiotic conditions on the dunes. I hypothesized that facilitation would be particularly significant on the foredune of subarctic coastal dune systems because of intense stresses (local and regional) and frequent disturbance in the form of sand deposition. Belowground and aboveground plant biomass was sampled at three different periods during the 1990 growing season along transects perpendicular to the shoreline on a coastal dune system in subarctic Quebec (Canada). The three herbaceous perennials found on the foredune (Honckenya peploides, Elymus mollis, and Lathyrus japonicus) were segregated in time during the growing season and in space along the topographical gradient. The biomass of Honckenya, the first species encountered as one progresses from the upper part of the beach towards the foredune ridge, was not correlated to substrate physicochemistry. However, the biomass of Elymus and that of Lathyrus, the next two species to appear along the flank of the foredune, were related to pH, Mg, Na, and Cl (negatively), and to P and Ca (positively). These results suggest variable linkages between substrate physicochemistry and plant species along the foredune, possibly in relation to species-specific tolerance for abiotic conditions and requirements for substrate resources or to microscale influence of the plants themselves on substrate physicochemistry. Removal experiments carried out over 2 years revealed only one significant unidirectional interaction between these three species along the topographical gradient, and little plant control over abiotic variables (e.g., soil temperature, wind velocity, and photosynthetically active radiation). Early primary succession on subarctic coastal dunes (and elsewhere) appears to be under the control of strong limiting abiotic conditions. As plants slowly gain more control over the physical environment, interspecific interactions (positive and negative) may become more significant. Key words: Elymus mollis, facilitation, Honckenya peploides, inhibition, Lathyrus japonicus, removal experiment, succession, tolerance.

The roles of photochemical and non-photochemical quenching in regulating photosynthesis depend on the phases of fluctuating light conditions

2021 ◽  
Author(s):  
Jimei Han ◽  
Lianhong Gu ◽  
Jeffrey M Warren ◽  
Anirban Guha ◽  
David A Mclennan ◽  
...  
Keyword(s):  
Interactive Effects ◽  
Photochemical Quenching ◽  
Limiting Factor ◽  
Require Time ◽  
Photosynthetic Productivity ◽  
Fluctuating Environments ◽  
Precise Relationship ◽  
New Perspective ◽  
High Level ◽  
Non Photochemical Quenching

Abstract The induction and relaxation of photochemistry and non-photochemical quenching (NPQ) are not instantaneous and require time to respond to fluctuating environments. There is a lack of integrated understanding on how photochemistry and NPQ influence photosynthesis in fluctuating environments. We measured the induction and relaxation of chlorophyll a fluorescence and gas exchange in poplar and cotton at varying temperatures under saturating and fluctuating lights. When the light shifted from dark to high, the fraction of open reaction centers in photosystem II (qL) gradually increased while NPQ increased suddenly and then remained stable. Temperature significantly changed the response of qL but not that of NPQ during the dark to high light transition. Increased qL led to higher photosynthesis but their precise relationship was affected by NPQ and temperature. qL was significantly related to biochemical capacity. Thus, qL appears to be a strong indicator of the activation of carboxylase, leading to the similar dynamics between qL and photosynthesis. When the light shifted from high to low intensity, NPQ is still engaged at a high level, causing a stronger decline in photosynthesis. Our finding suggests that the dynamic effects of photochemistry and NPQ on photosynthesis depend on the phases of environmental fluctuations and interactive effects of light and temperature. Across the full spectra of light fluctuation, the slow induction of qL is a more important limiting factor than the slow relaxation of NPQ for photosynthesis in typical ranges of temperature for photosynthesis. The findings provided a new perspective to improve photosynthetic productivity with molecular biology under natural fluctuating environments.

scholarly journals Interannual Variation in Root Production in Grasslands Affected by Artificially Modified Amount of Rainfall

2012 ◽  
Vol 2012 ◽  
pp. 1-10 ◽  
Author(s):  
Karel Fiala ◽  
Ivan Tůma ◽  
Petr Holub
Keyword(s):  
Interannual Variation ◽  
Plant Biomass ◽  
Growing Season ◽  
Lower Amount ◽  
Root Production ◽  
Climate Scenarios ◽  
Natural Rainfall ◽  
Plant Matter ◽  
Grassland Ecosystems ◽  
Below Ground

The effect of different amounts of rainfall on the below-ground plant biomass was studied in three grassland ecosystems. Responses of the lowland (dryFestucagrassland), highland (wetCirsiumgrassland), and mountain (Nardusgrassland) grasslands were studied during five years (2006–2010). A field experiment based on rainout shelters and gravity irrigation simulated three climate scenarios: rainfall reduced by 50% (dry), rainfall increased by 50% (wet), and the natural rainfall of the current growing season (ambient). The interannual variation in root increment and total below-ground biomass reflected the experimentally manipulated amount of precipitation and also the amount of current rainfall of individual years. The effect of year on these below-ground parameters was found significant in all studied grasslands. In comparison with dryFestucagrassland, better adapted to drought, submontane wetCirsiumgrassland was more sensitive to the different water inputs forming rather lower amount of below-ground plant matter at reduced precipitation.

scholarly journals Use of coccidiostat in mineral salt and study on ovine eimeriosis

2012 ◽  
Vol 21 (1) ◽  
pp. 16-21 ◽  
Author(s):  
Alberto Luiz Freire de Andrade Júnior ◽  
Patrícia Costa da Silva ◽  
Emerson Moreira de Aguiar ◽  
Francisco Glauco de Araújo Santos
Keyword(s):  
Weight Gain ◽  
Eimeria Species ◽  
The State ◽  
Mineral Salt ◽  
Limiting Factor ◽  
Eastern Region ◽  
Treatment Groups ◽  
Parasitological Diagnosis ◽  
Significant Difference ◽  
Sheep Production

Coccidiosis is a serious obstacle to sheep production, which is becoming a limiting factor, especially with regard to lamb production. However, there are few studies on this parasite in the State of Rio Grande do Norte. The aim of this study was to evaluate the action of decoquinate, added to mineral salt, for controlling Eimeria infection in lambs, and to identify which species are infecting sheep in the eastern region of the state. This study was carried out from August 2009 to January 2010, and used 76 animals. These were divided into two treatment groups: one with common mineral salt, and the other with mineral salt enriched with 6% micronized decoquinate. Fecal samples and body weight measurements were taken every 14 days for parasitological diagnosis, weight gain follow-up and quantitative analysis. The study showed that there was a significant difference in OPG only at the 7th collection, but no significant difference in weight gain. The Eimeria species found were E. ahsata. E. crandallis. E. granulosa. E. intrincata. E. ovina. E. faurei. E. ovinoidalis. E. pallida and E. parva. It was concluded that addition of decoquinate to mineral salt gave rise to lower oocyst elimination, thus favoring eimeriosis control in sheep.

Sign in / Sign up

Export Citation Format

Share Document