Spring Crops Research Articles

Особенности развития озимых и яровых культур на европейской территории России в сезоне 2019–2020 гг.

Особенности развития озимых и яровых культур на европейской территории России в сезоне 2019–2020 гг.

Climate and weather of the Southern Urals and their influence on agronomy

Changes in climate, precipitation and air temperature in the Southern Urals over the past 133 years are considered. A decrease in the climatic norm of atmospheric precipitation by 24 mm and an increase in the air temperature in the region by 1.2 º C were revealed. The main decrease in precipitation occurred during the growing season of early crops, and air temperatures in the autumn-winter period, which significantly changed the conditions for agronomy. The increasing aridity of the climate has worsened the conditions for growing spring crops. The applied system of rain-fed agriculture in Orenburg region provides the use of only 30–40% of annual precipitation. Early winter sowing of spring wheat in frozen ground with snow cover up to 10–15 cm is proposed. With them, seed germination, seedlings and tillering of plants are well provided with moisture and have favorable temperature conditions in April-May. Plants with a strong root system can get soil moisture up to 1.5 meters deep and effectively use small precipitation in June and July, which mainly moisturizes the soil to a depth of 5 cm. Early winter sowings of spring wheat are less susceptible to droughts, Favorable soil moisture and air temperature in the spring provide early shoots, plant development and 1.5–2-fold increase in yield. With early winter sowings, the efficiency of using annual precipitation increases to 50–55%.

Productivity and grain quality of various types of spring wheat depending on seeding rates and nutrition background on gray forest soil of the Pre-Kama Region of the Republic of Tatarstan

The results of two–year (2018–2019) studies on the effect of various seeding rates and nutritional backgrounds on the yield and grain quality of two types of spring wheat – soft wheat and emmer wheat (spelt) – are considered. The agrochemical characteristic of the gray forest soil of the experimental plot is as follows: the humus content in the layer of 0–20 cm was 2.9–3.4 % (Tyurin method), mobile phosphorus amount was 176–241 mg, exchange potassium amount was 77–109 mg/kg of soil (Kirsanov method). The degree of saturation with bases was 85.2–87.7 %, the pH of the salt extract was 5.6–5.8. Agrometeorological conditions of 2018–2019, on the whole, met the requirements for early spring crop seeding, HTC (hydrothermal coefficient) was 0.85–1.2. Two levels of mineral nutrition were studied in the experiment (natural background, without fertilizing, NRK for the planned grain yield of 3 t/ha), four seeding rates against each nutrition background: 4, 5, 6 and 7 million germinating seeds per 1 ha. The seedling completeness in both types of wheat over an average of 2 years depended on the seeding rate, regardless of the background of nutrition. In soft wheat of Ulyanovskaya 105 variety, against a natural background, with an increase in the sowing rate from 4 to 7 million germinating seeds per ha, the seedling completeness decreased and amounted to from 82.5 to 76.3 %, in spelt, it was 84.7–78.6 %. On a fertilized ground it was, respectively, 83.4–78.0 and 84.1–77.6 %. Good preservation of plants in both types of wheat from the number of sown seeds and seedlings was noted when the sowing rate was reduced from 7 to 4 million: without fertilizer 82.6–88.5 % in common wheat and 83.5–90.4 % of spelt. On a fertilized ground it amounted, respectively, to 84.3–90.5 and 86.5–92.3 %. Changes in nutritional background by introducing calculated doses of mineral fertilizers for all options with seeding rates on average for 2018–2019 yielded an increase in soft wheat by 0.94 tons of grain per hectare and by 0.61 tons of spelt. The highest conversion efficiency of fertilizers at a sowing rate of 6 million in common wheat was 8.1 kg of grain per 1 kg of a.a., for spelt at a sowing rate of 4 million the figure was 5.6 kg per 1 kg of a.a.

Rainwater Harvesting with Solar and Gravity Powered Irrigation for High Tunnels

HIGHLIGHTS Captured rainwater supplied nearly all the irrigation required for high tunnels in Tennessee. Solar pumping and/or gravity flow adequately supplied the pressure required for irrigation in high tunnels. Rainwater harvesting costs need to be reduced in order to be more competitive with alternate water sources. Abstract . High tunnels use clear plastic film over a large metal frame to trap solar radiation as heat in order to extend the crop growing season and reduce environmental stress. High tunnels differ from high tech greenhouses in that they use the natural soil as the growing media and use natural ventilation without fans or heaters to control the growing environment. High tunnels can provide some of the benefits of greenhouses at a much lower cost. However, the protective cover cuts-off rain water to the crop and significantly modifies the crop-water use environment. In order to reduce reliance on external sources of water, The University of Tennessee–Biosystems Engineering and Plant Science Departments implemented three types of rainwater harvesting (RWH) for high tunnels that did not require an external source of power for irrigation: gravity flow, solar battery-powered pumping, and solar transfer pumping. RWH by gravity-flow stored water captured off the high tunnels at a high enough elevation to deliver water for irrigation at very low pressure while solar battery-powered pumping delivered pressurized water directly to the irrigation system. Solar transfer pumping moved harvested rainwater to a higher elevation tank that used gravity flow to irrigate at intermediate pressures. These RWH systems were designed to store 64 mm of rainfall from the high tunnel cover (6400 L per 100 m2 of footprint area) and were able to provide 75% to 100% of the spring crop and 90% to 100% of the fall crop irrigation based on 16 experiments over six years. The RWH systems were ranked in order of increasing cost, maintenance, and complexity as follows: 1) gravity flow, 2) solar transfer pumping, and 3) solar battery-powered pumping. However, all RWH systems had high initial cost when compared to well and municipal water supplies, $12,750 to $15,950 for two 9.2- × 29-m high tunnels. Significantly lower cost rain gutters and water storage were identified but not yet tested for RWH in high tunnels. Keywords: Drip irrigation, Evapotranspiration, Gravity irrigation, Greenhouses, High tunnels, Microirrigation, Rainwater harvesting, Solar pumping.

Crop classification from full-year fully-polarimetric L-band UAVSAR time-series using the Random Forest algorithm

Accurate and timely information on the distribution of crop types is vital to agricultural management, ecosystem services valuation and food security assessment. Synthetic Aperture Radar (SAR) systems have become increasingly popular in the field of crop monitoring and classification. However, the potential of time-series polarimetric SAR data has not been explored extensively, with several open scientific questions (e.g. the optimal combination of image dates for crop classification) that need to be answered. In this research, the usefulness of full year (both 2011 and 2014) L-band fully-polarimetric Uninhabited Aerial Vehicle Synthetic Aperture Radar (UAVSAR) data in crop classification was fully investigated over an agricultural region with a heterogeneous distribution of crop categories. In total, 11 crop classes including tree crops (almond and walnut), forage crops (grass, alfalfa, hay, and clover), a spring crop (winter wheat), and summer crops (corn, sunflower, tomato, and pepper), were discriminated using the Random Forest (RF) algorithm. The SAR input variables included raw linear polarization channels as well as polarimetric parameters derived from Cloude-Pottier (CP) and Freeman-Durden (FD) decompositions. Results showed clearly that the polarimetric parameters yielded much higher classification accuracies than linear polarizations. The combined use of all variables (linear polarizations and polarimetric parameters) produced the maximum overall accuracy of 90.50 % and 84.93 % for 2011 and 2014, respectively, with a significant increase of approximately 8 percentage points compared with linear polarizations alone. The variable importance provided by the RF illustrated that the polarimetric parameters had a far greater influence than linear polarizations, with the CP parameters being much more important than the FD parameters. The most important acquisitions were the images dated during the peak biomass stage (July and August) when the differences in structural characteristics between most crops were the largest. At the same time, the images in spring (April and May) and autumn (October) also contributed to the crop classification since they respectively provided unique information for discriminating fruit crops (almond and walnut) as well as summer crops (corn, sunflower, and tomato). As a result, the combined use of only four acquisitions (dated May, July, August, and October for 2011 and April, June, August, and October for 2014) was adequate to achieve a nearly-optimal overall accuracy. In light of the promising classification accuracies demonstrated in this research, it becomes increasingly viable to provide accurate and up-to-date crops inventories over large areas based solely on multitemporal polarimetric SAR.

Simulating soil surface temperature under plastic film mulching during seedling emergence of spring maize with the RZ–SHAW and DNDC models

Plastic film mulching has been widely used to increase soil temperature in areas with a cold spring. Reliable simulation of mulched soil surface temperature is important for initial growth of spring crops. The hybrid Root Zone Water Quality-Simultaneous Heat and Water (RZ-SHAW) model and the Denitrification-Decomposition (DNDC) model use different approaches to quantify the effect of plastic film mulching on soil temperature. A two-year field study was conducted to compare the performance of the RZ-SHAW model and DNDC model for simulating the 5-cm soil temperature (T5) under varying plastic film mulching coverages during seedling emergence of spring maize. Three treatments were used in this study: no mulching (PM0), full plastic film mulch (PM100), and partial plastic film mulch with 60 % coverage, i.e. 60 cm width of plastic every meter (PM60). Compared with no mulching, PM100 and PM60 treatments enhanced daily maximum and average T5 (2.53℃ and 1.25℃, respectively; p < 0.05) while not affecting the diurnal sinusoidal phase change of T5 (2.45℃ and 1.21℃, respectively; p < 0.05). The RZ-SHAW model was robust for T5 simulation under mulching condition with RMSE and NSE ranged from 2.01℃ to 2.51℃ and 0.68 to 0.84, respectively, while the DNDC model failed to predict T5 for mulched soil with RMSE and NSE ranged from 2.79℃ to 4.33℃ and 0.25 to 0.46, respectively. Employing Tms (air temperature between plastic film and soil surface) to replace soil surface temperature may be one reason for the poor T5 simulation of DNDC in mulched plots. By contrast, the RZ-SHAW model ran a complete calculation for heat and vapour transfer within the mulched layer, which robustly simulated atmosphere–soil surface temperature gradient in the plant canopy, surface covering, and soil surface in a broader range of climatic conditions. Additionally, the longwave radiation reflected back to the soil surface by the plastic, which was not considered by DNDC model, was important and enhanced T5 simulation performance for RZ-SHAW under mulching condition. It suggested to imbed the SHAW module into DNDC for a sufficiently precise simulation of soil temperature and gas emission.

Population dynamics and habitat use by Northern Lapwing Vanellus vanellus in agricultural landscape of Dravsko and Ptujsko polje (NE Slovenia)

Abstract The Northern Lapwing numbers across Europe are declining owing to its insufficient breeding success. To determine the size, dynamics and habitat use of the lapwing population at Dravsko and Ptujsko polje, a survey was carried out between 2016 and 2018. In 2016, 2017 and 2018, we recorded 148, 130, and 117 pairs, respectively. The population declined during the study and the population trend is uncertain. Approximately 12 to 21% of the national lapwing population was recorded at Dravsko and Ptujsko polje, making them one of the most important breeding areas in Slovenia. The majority of lapwings were found in bare tilled fields and fields with young spring crops that enable unbroken all-round views. Crop data analysis showed a significant preference for maize fields which are mostly bare tillage at the start of the incubation period and therefore act as an ecological trap for lapwings due to the time coincidence of the nesting period and farming operations. For the protection of the lapwing in Slovenia, we recommend a time limit of farming operations or avoiding individual nests while working in the field. Both measures are recommended to be implemented in combination with the provision of suitable foraging habitat for chicks. For greater effectiveness, we propose priority implementation of conser vation measures on traditiona l breeding sites.

A Crop Group-Specific Pure Pixel Time Series for Europe

Long timeseries of Earth observation data for the characterization of agricultural crops across large scales are of high interest to crop modelers, scientists, and decision makers in the fields of agricultural and environmental policy as well as crop monitoring and food security. They are particularly important for regression-based crop monitoring systems that rely on historic information. The major challenge lies in identifying pixels from satellite imagery that represent pure enough crop signals. Here, we present a data-driven semi-automatic approach to identify pure pixels of two crop groups (i.e., winter and spring crops and summer crops) based on a MODIS–NDVI timeseries. We applied this method to the European Union at a 250 m spatial resolution. Pre-processed and smoothed, daily normalized difference vegetation index (NDVI) data (2001–2017) were used to first extract the phenological data. To account for regional characteristics (varying climate, agro-management, etc.), these data were clustered by administrative units and by year using a Gaussian mixture model. The number of clusters was pre-defined using data from regional agricultural acreage statistics. After automatic labelling, clusters were filtered based on agronomic knowledge and phenological information extracted from the same timeseries. The resulting pure pixels were validated with two different datasets, one based on high-resolution Sentinel-2 data (5 sites, 2 years) and one based on a regional crop map (1 site, 7 years). For the winter and spring crop class, pixel purity amounted to 93% using the first validation dataset and to 73% using the second one, averaged over the different years. For summer crops, the respective values were 61% (91% without one critical validation site) and 72%. The phenological analyses revealed a clear trend towards an earlier NDVI peak (approximately −0.28 days/year) for winter and spring crops across Europe. We expect that this dataset will be useful for various applications, from crop model calibration to operational crop monitoring and yield forecasting.

The study of the dependence of spring crops yield on the abiotic environmental factors using nonlinear interpolation

The article discusses the effect of abiotic environmental factors on crop yields. Abiotic factors cannot be changed by human activity; therefore, considering their impact on yield is very important for predicting crop yields. The article analyzes the dependence of spring wheat yield on such abiotic environmental factors as average ten-day air temperatures during the growing season, ten-day amounts of precipitation during the growing season and the Selyaninov hydrothermal coefficient during the growing season. To identify dependencies, the authors applied a non-linear approximation method using a third-degree polynomial dependence with one variable. The study was conducted during the most important growing season of spring wheat, in May and June. The authors show the equations of the third-degree polynomial dependences and graphs, as well as their graphic interpretation. Based on the obtained graphs, the authors have analyzed favorable intervals of abiotic factors for the formation of high yields of spring wheat. The authors indicate the most optimal temperature and humidity conditions for each ten days of May and June. These dependences are suitable not only for spring wheat but also for other spring grain crops, such as oats and barley.

A method to assess the impact of soil available water capacity uncertainty on crop models with a tipping‐bucket approach

AbstractMost agronomic crop models use a reservoir tipping‐bucket approach to model the water budget in the soil. Soil available water capacity (AWC) is the main soil property considered in this approach. Because AWC is difficult to measure, uncertainty in AWC may be high. We developed a method using a specific kriging technique to determine the effects of uncertainty in AWC on crop model predictions. The AqYield crop model was used as an example to assess the effects of uncertainty in AWC on two agronomic output variables (grain yield and drainage). The factors considered were the climatic region, crop type and soil depth. We assessed the results using the coefficient of variation (CV) and sets of critical values for which CV exceeded 5, 10 and 15%. The experiment provided insight into the criticality of AWC uncertainty over a wide range of agropedoclimatic situations according to crop, model and output of interest. The method revealed the greater effect of AWC uncertainty on both outputs for the spring crop than for the winter crop and identified cases where AWC uncertainty was critical. There was a stronger effect of AWC uncertainty on yield for shallow soil and climatic water deficit conditions. For each situation, the AWC uncertainty levels were determined above or below which the impact becomes significant on a given output because the sensitivity was very dependent on climate–crop–soil combinations. It was also observed that uncertainty in AWC had little effect in AqYield for a wide range of situations. The method developed uses a small number of model simulations to produce accurate results to better understand the impact of this major soil input data according to the target model and specific objectives. It could help to determine the level of accuracy needed in AWC measurement, depending on the objectives.Highlights The method quantifies the effects of AWC uncertainty on crop models with a tipping‐bucket approach. This method can assess the impact of uncertainty with only a few runs using a kriging approach. The method identifies critical situations for a wide range of agropedoclimatic conditions. Critical region graphs give critical thresholds for accuracy needed in AWC.

Canola Breeding for HUMAN HEALTH

Canola Breeding for HUMAN HEALTH

Long-Term Water Balance of Selected Field Crops in Different Agricultural Regions of the Czech Republic Using Fao-56 and Soil Hydrological Approaches

Long-term water balance (WB) of four selected crops (winter wheat, oilseed rape, silage maize, semi-early potatoes) was determined at the field block scale in the Czech Republic for all agricultural growing areas (AGAs): maize-, beet-, potato- and mountain-AGAs for the 1981–2010 period. A novel approach for the calculation of WB was employed, which combined the FAO-56 method for crop water requirements (CWRs) with sources of available water from precipitation, soil, and groundwater. The computed WB was divided into four categories of soil water availability based on soil hydrolimits and crop features: Categories 1 and 2 with zero or mild occurrence of crop water stress; categories 3 and 4 with intermediate and severe occurrence of crop water stress. The winter crops were affected by water stress to a lesser extent (the area of categories 3 and 4: wheat 20.1%, oilseed rape 14.5%) as compared with spring crops (the area of categories 3 and 4: maize 39.6%, potatoes 41%). The highest water deficit was recorded for all crops in the maize-AGA due to low precipitation and high CWRs. Most available water was revealed to occur in the mountain-AGA. A strong need for the adoption of measures towards the optimization of water regimes on agricultural land was indicated. The present study shows a promising approach for evaluating and proposing changes of area of cultivated crops with the appropriate tillage and agricultural water management in terms of satisfactory crop water requirements.

Economic Analysis of Silkworm Rearing and Cocoon Production in Bilaspur District of Himachal Pradesh

Sericulture is an agro-based multitudinous activity which involves cultivation of mulberry, production of laying, rearing of silkworms for cocoons, marketing and reeling of cocoons for value added products such as processing and weaving of the yarn. It is a short gestation period labour intensive enterprise which can go a long way in promoting inclusive growth and alleviating poverty in rural areas. The present study was therefore carried out in order to analyse investment and returns pattern of cocoon production in Bilaspur district of Himachal Pradesh. Two-stage random sampling and proportional allocation method was used to prepare a list of sample farmers. Out of 60 silkworm rearers, 19 were large and 41 were small. The dry cocoon production per farm on small and large category was estimated at 8.25 kg (6.20 kg in spring and 2.05 kg in autumn) and 19.51 kg (16.67 kg in spring and 2.84 kg in autumn). The dry cocoon production per ounce of seed was found to be 20.28 kg and 26.14 kg on small and large category households for both the seasons together. The fixed cost of production / ounce for spring crop varied from 9.92 per cent on small farms to 14.75 per cent on large farms. The variable cost varied from 90.08 per cent on small farms to 85.25 per cent on large farms implying the economical use of fixed and variable resources by large growers. The gross returns per ounce seed basis ranged between ` 1,626 and ` 5,535 on small and large farms for the spring crop. The autumn crop was found to give negative returns; therefore farmers should be provided with technology which could reduce the moisture in the rearing room, develop humidity resistant races of silkworms as well as develop varieties of mulberry plantation which may yield good leaves just after rainy season.

Evaluation of adaptive capacity of genotypes of spring cereals in arid conditions of the Astrakhan region

Objects of research were: spring wheat Saratovskaya 70-st, Cardinal, 3 Curenta, Madam, Nil avocet yr7's, Angarida; spring barley Ratnik-st, Medium 135, grace, Vakula, Brassa; spring oats Showjumping-st, Leo, Bulan, Kuranin. As a result of the study of these varieties of spring crops, the most adapted to local soil and climatic conditions samples were identified. The selected samples were distinguished by high biological plasticity, growth and development rates, maximum use of moisture, as well as the ability to form high grain yields.

Growing Degree Day and Seed Yield Relationships in Mustard (Brassica juncea L.) Under Different Sowing Seasons and Locations of Turkey

Mustard is grown in mild winter regions as late fall and in hard winter regions as late spring crop. Mustard has high degree of adaptability under wide range of climatic conditions in Turkey. Temperature is an important weather parameter affecting the growth and development of the mustard. The sum growing degree day (GDD) for a growing season is related to plant development which is depends on the accumulation of heat. The aim of this study was to determine the adaptation of mustard, under sowing seasons (spring and fall sowing) and locations in terms of crop growth (emergence, 50% flowering, physiological maturity, and sum growing degree days) and seed yield of mustard. Two-year field experiments in a split-plot design with four replications were carried out during 2013-14 and 2014-15 growing seasons at eight different ecological locations. These locations included Ankara, Aydin, Erzurum, Eskisehir, Isparta, Tekirdag, Tokat and Sanliurfa provinces of Turkey-as classified by Koppen-Geiger ecological conditions. The Brassica juncea L. (mustard seeds) were collected from wild conditions in the Konya province of Turkey. The results showed that, sowing seasons and locations significantly affected seed yield and GDD. The maximum seed yield of 3754.9 kg ha-1 was obtained from Tokat (warm humid) during fall sowing with total accumulated GDD of 1512.1 °C for mustard. Sum growing degree-days accumulated in different sowing seasons and locations occurred between 1132.0 °C and 2285.1 °C depending on the related ecological conditions. Fall season crop in Aydin location had the maximum growing degree days. Overall, fall season accumulated more growing degree days due to longer period of sunshine in comparison to spring season with less sunshine days resulting in longer vegetation period.

Soil Water Dynamics with Spring Camelina in a Three‐Year Rotation in Washington's Winter Wheat–Fallow Region

Core Ideas The soil water dynamics of 3‐yr winter wheat–camelina–summer fallow and 2‐yr winter wheat–summer fallow rotations were measured for 8 yr. At harvest, there was less soil water after camelina than after winter wheat in the 2‐yr rotation. The water deficit persisted through the 13‐mo fallow period and decreased the yield of 3‐yr vs. 2‐yr winter wheat. Increased cropping intensity may increase risk and variability in dry environments. Camelina [Camelina sativa (L.) Crantz] of the Brassicaceae family is a short‐season drought‐ and frost‐tolerant oilseed. Camelina has been promoted as an alternative crop for the low‐precipitation (&lt;350 mm annually) Mediterranean‐like climate region of the US inland Pacific Northwest, where a monoculture 2‐yr winter wheat (Triticum aestivum L.) (WW)–summer fallow (SF) rotation is widely practiced. An 8‐yr experiment was conducted to compare a 3‐yr WW–camelina–SF rotation with the typical 2‐yr WW–SF rotation to analyze the soil water dynamics of these two crop rotations. Growing spring‐planted camelina reduced soil water content at the beginning of the fallow; this reduction resulted in an average of 21 mm less water at WW planting and a 170 kg ha‐1 reduction in grain yield compared with WW–SF. We show that (i) the deep‐rooted broadleaf weed Russian thistle (Salsola tragus L.) present in camelina most years was the most likely reason for greater in‐crop soil water use than with WW–SF, and (ii) the limited camelina residue was probably responsible for greater evaporative loss during the spring to late summer segment of the fallow. We report the first findings from the Pacific Northwest drylands of greater water use by a cool‐season spring crop versus WW and greater evaporative loss during the summer caused by lack of residue in a minimum‐tillage SF comparison. Here, extending the crop rotation to include camelina was costly in terms of water use, surface soil residue cover, soil water storage during the fallow, and WW grain yield.

The Potato Tuber Moth, Phthorimaea operculella (Zeller), in India: Biology, Ecology, and Control

Phthorimaea operculella occurs in almost all potato-producing states in India and is considered to be a major potato pest in several states. The larva attacks all vegetative parts of the potato, and most economic damage occurs to potato tubers both before harvest in the field and during storage. The tuber damage in storage has been stated to range from 1 to 72.5% in the endemic states. In Karnataka and Himachal Pradesh, up to 100% losses in storage have been reported. In India, maximum moth activity in the spring (January–May) crop occurs during March–May, whereas in the summer (May–October) crop in hilly areas, peak activity occurs in October. Temperature is positively correlated, whereas RH has a negative influence. In stores, maximum activity occurs in July. Moderate temperature around 23–24 °C is conducive for oviposition and development. Development time from egg–adult varies considerably (20–165 days). In tropics and subtropics, 7–13 generations are completed annually. For its management, use of healthy seed, field sanitation, deep planting, and proper ridging contribute significantly. In India, generally, 1–2 insecticide applications are given for its control in spring and autumn (October–December) crops. Field releases of Copidosoma koehleri and Chelonus blackburni integrated with Bacillus thuringiensis and Phthorimaea operculella granulosis virus are effective in areas having moderate temperature and high RH. In storage, dry leaves of Eucalyptus, Lantana, Ageratum, Eupatorium, soapnut, and wheat straw offer significant reduction in infestation. CIPC is helpful in reducing losses due to sprouting, but it also indicates very good potential against P. operculella in storage.

Scientific bases of the humus stabilization in ordinary chernozem in Russia

&lt;p&gt;The influence of long-term use of mineral and organic fertilizers, crop rotations, plant residues, soil treatment systems on humus content of common chernozems and stabilization of productivity of field crops in the arid conditions of the Middle Volga region is considered on the example of researches in the Samara area. The zone climate of field experiments is characterized as extremely continental. The sum of the active temperatures (above 10°C) is 2,800-3,000°C. The average annual rainfall is 454.1 mm with fluctuations over the years from 187.5 mm to 704.6 mm. At some years, precipitation does not happen within a month or more. Hydrothermal index in May-August is 0,7, the duration of the frost-free period is 149 days. If the humus content in the region is 4.35-4.52%, then, it is necessary to introduce 6.7-8.0 t/ha of manure per year to maintain the balance of the deficit. The introduction of biological methods for the conservation and reproduction of soil fertility (green fertilizers, perennial grasses, straw as fertilizer) reduces the loss of humus by 0.15-0.24 t/ha. This makes it possible to increase the payback of mineral fertilizers, which must be taken into account when developing fertility reproduction systems for soils. In the variants with minimal and differentiated cultivation of the soil during crop rotation in 30 years of the study, the loss of humus in the 0-30 cm layer decreased by 0.04 - 0.73% (43-789 kg per year with maximum values in the combination of direct seeding of spring crops with deep loosening for a number of crop rotations is 4.14%, significantly exceeding the control (by 0.54%). The decrease in soil fertility in the variants with constant plowing and minimal tillage contributed to an increase in the conjugation of productivity of crops with humus. Based on the research, in order to preserve the fertility of the soil of ordinary chernozem, it is necessary to use green fertilizer, leguminous perennial grasses. In the regional rotations of crop production, new generation technologies are recommended, the basis of which is differentiated tillage with the use of crushed straw as fertilizer.&lt;/p&gt;

Shifting sowing of camelina from spring to autumn enhances the oil quality for bio-based applications in response to temperature and seed carbon stock

Camelina [Camelina sativa (L.) Crantz] is an emerging oilseed crop that is attracting the interest of farmers in relation to its high environmental adaptability and low-input request. Camelina oil is an outstanding feedstock for the bio-based industry, since its unique composition allows multiple applications. Being spring camelina biotypes able to grow as both an autumn and spring crop in mild climates, and sowing date directly influences the temperature occurring during the seed filling stage, which likewise influences the final seed quality in terms of seed weight, oil and fatty acid (FA) content. A detailed study on the response of spring camelina to the effects of autumn and spring sowing is reported herein. The spring variety Midas was sown at six different sowing dates at the experimental farm of Bologna University (Italy) during two consecutive growing seasons (2015-16 and 2016-17). In parallel, three experiments were also carried out in a growth chamber with different ranges of temperatures during the seed filling period. Samplings of immature seeds over time, in both controlled environment and open field trials, allowed identification of a “time frame” in which the main variations in FA kinetics occurred. A “critical period”, from 350 to 540 growing degree day after the start of flowering (GDD-AF) was identified as that in which the closest relation between the final camelina FA composition and temperature, during the seed filling stage, occurred. The adoption of this empirical model permitted early evaluation (about 10 d before harvest) of the final camelina oil composition with relevant implications for the bio-based industry. Autumn sowing dates were associated with increased plant aboveground biomass, seed yield, seed oil content, seed weight (TKW), and content of linolenic and eicosenoic acid. Since eicosenoic acid is a valuable feedstock for the bio-based industry, growing spring camelina, as an autumn crop, in the Mediterranean region allows significantly increase the quantity of this infrequent FA.

Estimating the farm-level economic costs of spring cropping to manage Alopecurus myosuroides (black-grass) in UK agriculture

AbstractCrop rotation is a non-chemical strategy adopted by farmers to manage weeds. However, not all crops in a rotation are equally profitable. Thus, there is potentially a trade-off between the costs and benefits of this strategy. The objective of the current study is to quantify this trade-off for the rotational control of an important weed (Alopecurus myosuroides). Data from 745 farms were used to parameterize a farm-level mixed-integer goal-programming model of the economics of spring cropping for weed control in UK agriculture. On average, the short-term loss of profit from spring cropping is greater than the benefits in terms of reduced herbicide usage and yield increases. These costs are greater when weed densities are low, so that spring cropping is an expensive strategy in the early stages of an infestation. However, there is a great deal of farm-to-farm variation: factors such as soil type and farm size are important and the current study highlights that economic modelling at the farm level is important in enabling farmers to make informed decisions. In general, however, if spring cropping is to be a successful strategy then the benefits to farmers will be in terms of long-term reductions in weed densities, but this will be at the expense of short-term profitability.