Wheat Stubble Fields Research Articles

Study on Operating Vibration Characteristics of Different No-Tillage Planter Row Units in Wheat Stubble Fields

Study on Operating Vibration Characteristics of Different No-Tillage Planter Row Units in Wheat Stubble Fields

Influence of the harvesting method on the processes of moisture accumulation and yield capacity

BACKGROUND: A feature of the climate of the steppe zones of Western Siberia is the frequent recurrence of droughts. Accumulation and preservation of solid precipitation in the form of snow on field in winter is a relevant task, since this directly affects the accumulation of productive moisture in soil by the time of sowing and, as a result, the formation of the future harvest.
 AIMS: To determine the influence of the snow cover level, moisture reserves and productive moisture in the soil on a stubble background, harvested with a thresher for direct combining and a rippler on the yield capacity of spring wheat.
 METHODS: The field experiment was carried out in 2021-2022 in the steppe zone of the Omsk region at the Novouralskoye Scientific and Production Enterprise of the Omsk Agrarian Scientific Center. In the autumn of 2021, sections of the field were marked out for measurements: wheat stubble field after the thresher for direct combining, wheat stubble field after the rippler. In March 2022, indicators of the height of the snow cover and moisture reserves in the snow were determined on the marked areas using the VS-43 balance snow gauge. In the spring, wheat was sown with the machine-tractor unit, consisting of the RSM 2400 tractor and the Amazone Condor 15001-C sowing facility. In autumn, the chosen field sections were harvested with the Sampo-250 seed-production harvester.
 RESULTS: It was found that after harvesting with the thresher for direct combining with a stubble background of about 15 cm, there is a decrease in the moisture reserve in the one-meter-depth layer by almost 2 times, down to 48.6 mm, by the spring period. The moisture reserve on a high stubble background, after the operation of the rippler, on the contrary, was able to persist, as there were 96.6 mm of productive moisture in the one-meter-depth layer by the time of sowing. The average grain yield on the field section sown after the rippler was 1.16 t/ha. The average grain yield on the field section sown after harvesting with the thresher for direct combining was 1.06 t/ha. Thus, the grain increase was 0.1 t/ha or 9.4%.
 CONCLUSIONS: The carried out field experiment indicates that, when harvesting with a rippler, there is a twofold increase in productive moisture by the time of sowing, while the increase in the yield of spring soft wheat grain was 9.4%.

Field Variation Characteristics of Sprayer Boom Height Using a Newly Designed Boom Height Detection System

To ensure boom sprayer safety and spraying efficiency, the sprayer boom height must be adjusted during pesticide application. The field variation characteristics of the sprayer boom height are the basis of the boom balance adjustment. A boom height detection system based on ultrasonic sensors was designed. Field tests were performed in 2.0 ha of vacant fields and 13.44 ha of wheat stubble fields. A signal processing method based on the K-means clustering algorithm was used to preprocess the ultrasonic sensor data. The results showed that the K-means clustering algorithm could effectively improve the detection accuracy of an ultrasonic sensor. The boom height variation was greatest at the sides of the boom, and the primary frequencies of the boom height variation were concentrated within a low-frequency band from 0 Hz to 1 Hz. The U-turn operation was more likely to cause the boom to contact the crop canopy or the ground than row operation. As the spraying speed increased, the maximum boom height variation and maximum roll angle increased; these primary components decreased in frequency, and the amplitude clearly increased. The maximum boom height variation exceeded 50 cm, and the maximum roll angle exceeded 3°, which not only aggravated the droplet drift but also caused damage to the boom and nozzles due to contact with the ground or the crop canopy. These findings can provide a theoretical basis for use in the development of an automatic boom height adjustment system.

The effect of various after-ripening temperature regimens on the germination behaviour of Ambrosia artemisiifolia

Ambrosia artemisiifolia (common ragweed) is an annual weed known to infest crops and disturbed areas, and cause human pollinosis. To examine the effect of different thermal regimens on seed germination, during seed after-ripening, a study was conducted for two years. In 2012 (year 1) and 2013 (year 2), ragweed seeds collected from a single wheat stubble field were divided and stored under one of the five temperature regimens: constant −20 °C, +5 °C, room temperature (18 °C), +25 °C, and field conditions. Germination tests were performed every 15 days of storage from day 17 to day 213. Storage conditions showed a strong influence on ragweed seed germination duration. At constant low temperatures (−20 °C), seed behaved in an opposite manner depending on the year; in year 1 germination was inhibited while it was stimulated in year 2. At higher temperatures, seed dormancy was unbroken due to a lack of exposure to low temperatures. Under field conditions, seeds reached a high level of germination after a few days of storage due to temperature fluctuations. The different behaviours of ragweed seeds shown at constant temperatures revealed different dormancy depths in the two years that might be due to population variability and maternal environment differences during seed maturation.

The performance of a fluted coulter for vertical tillage as affected by working speed

Vertical tillage is an efficient and effective tillage practice for conservation agriculture. However, the performance of vertical tillage tools has not been well documented. In this study, two vertical tillage tools: 8-wave and 13-wave coulters, were tested in a wheat stubble field at three different working speeds: 12, 16, and 20km/h, to examine the effects of tool geometry and working speed on the tillage performance of the fluted coulters. Soil disturbance width, soil throw width, and soil sticking on the coulter as well as residue cover were measured. The results showed that the soil disturbance width was significantly different among the working speeds and between two coulters while the other measured variables were only affected by the working speed. The 13-wave coulter had a 17% lower soil disturbance width as compared with the 8-wave coulter. Increasing the working speed (from 12 to 16km/h and from 12 to 20km/h) increased the soil disturbance width by 7.0 and 13.1% and the soil throw width by 14.3 and 45.1% respectively, but decreased the soil sticking by 1.4 and 76.6% and the residue cover by 5.1 and 11.0% respectively. Generally speaking, the effect of working speed was more dominant than the coulter geometry on the tillage performance of the fluted coulters. For long-term no-tillage farmers with excessive residue concerns, the 8-wave coulter working at 20km/h would be beneficial for sustainable farming practice.

Droplet-Based Microfluidics Platform for Ultra-High-Throughput Bioprospecting of Cellulolytic Microorganisms

Discovery of microorganisms producing enzymes that can efficiently hydrolyze cellulosic biomass is of great importance for biofuel production. To date, however, only a miniscule fraction of natural biodiversity has been tested because of the relatively low throughput of screening systems and their limitation to screening only culturable microorganisms. Here, we describe an ultra-high-throughput droplet-based microfluidic system that allowed the screening of over 100,000 cells in less than 20min. Uncultured bacteria from a wheat stubble field were screened directly by compartmentalization of single bacteria in 20 pl droplets containing a fluorogenic cellobiohydrolase substrate. Sorting of droplets based on cellobiohydrolase activity resulted in a bacterial population with 17- and 7-fold higher cellobiohydrolase and endogluconase activity, respectively, and very different taxonomic diversity than when selected for growth on medium containing starch and carboxymethylcellulose as carbon source.

除草の風土〔26〕東海地方のコムギ刈跡における非選択性茎葉処理除草剤による帰化雑草の防除

除草の風土〔26〕東海地方のコムギ刈跡における非選択性茎葉処理除草剤による帰化雑草の防除

A Comparison of an Experimental Plow with a Moldboard and a Disk Plow on the Soil Physical Properties

The moldboard plow is the most popular tillage tool in Turkey. However, the efficiency of the moldboard plow is poor compared to rotary tillage tools and it does not produce good soil conditions. Experiments were conducted on a wheat stubble field to compare the effects of an experimental plow (EP), a disk plow (DP), and a moldboard plow (MP) on soil bulk density, moisture content following tillage, cone index, and aggregate size distribution. The experiments were carried out on a silty loam soil, at a constant depth (200 mm), and with three travel speeds (4.5, 5.4, and 6.3 km h-1). The results showed that the type of plow did not significantly affect the soil bulk density, the moisture content following tillage, and the cone index. However, for spring tillage, the EP caused more moisture to be stored in the 0- to 100-mm top layer, compared to the MP and the DP. This is beneficial for germinating the seeds as they can find enough moisture on the top layer. The EP was found to reduce aggregate size more than the MP and the DP. Also, the EP produced a soil aggregate size distribution that is typically desirable as a seedbed. The effect of travel speed on the soil physical properties was not statistically significant. As the travel speed increased, the soil aggregate size and the moisture content following tillage decreased while the cone index and the bulk density increased.

Experimental study on wind erosion of surface soil in subsoiling wheat stubble fields

Experimental study on wind erosion of surface soil in subsoiling wheat stubble fields

Incorporating sheep into dryland grain production systems: I. Impact on over-wintering larva populations of wheat stem sawfly, Cephus cinctus Norton (Hymenoptera: Cephidae)

Wheat stem sawfly (WSS), Cephus cinctus Norton (Hymenoptera: Cephidae) is the most damaging insect pest to Montana's $ 1 billion dollar per year grain industry. Current WSS control methods are either expensive, reduce wheat yields, or are not effective. Our objective was to compare burning, grazing, tilling, trampling and clipping wheat stubble fields on over-wintering WSS larval populations. Treatments were evaluated in three experiments using a randomized complete block design and four replications at each site. Eight, six, and two sites were used for Experiments 1, 2, and 3, respectively. Contrast statements were used to make pre-planned comparisons among treatments. For Experiment 1, treatments were fall tilled, fall grazed, spring grazed, fall and spring combined (Fall/Spr) grazed, and an untreated control. Five mature ewes were confined with electric fence to 111 m 2 plot for 24 h in the fall and spring grazed treatments resulting in a stocking rate of 452 sheep d/ha. For Fall/Spr, the stocking rate was 904 sheep d/ha. For Experiment 2, treatments were fall grazed, fall burned, fall tilled, and an untreated control. In Experiment 3, treatments were fall trampled, spring trampled, Fall/Spr trampled, hand clipped to a stubble height of 4.5 cm, and an untreated control. Trampled treatments were done at the same stocking rates as grazing treatments but sheep were muzzled to prevent intake. Wheat stem sawfly larval numbers were collected in the fall and spring, pre- and post-treatment, respectively, by collecting all plant material from three, 0.46 m lengths of row and counting the number of live larvae present. In Experiment 1, WSS mortality was greater ( P < 0.01) for the mean of all grazed treatments (68.4%) than either control (43%) or tilled (47%) plots. Mortality did not differ ( P = 0.75) between fall (67%) and spring (64%) grazed plots but was greater ( P = 0.02) for Fall/Spr (74%). In Experiment 2, larva mortality was greater ( P < 0.01) for fall grazed (63%) than burned plots (52%). In Experiment 3, WSS mortality was greater ( P < 0.01) for the mean of all trampling treatments (57%) than either control (33%) or clipped (32%) plots. Mortality did not differ ( P > 0.25) between fall (54%) and spring trampling (47%) but was greater ( P = 0.01) for Fall/Spr (70.6%). No differences ( P > 0.25) were detected for WSS mortality when grazing was compared to trampling. These results indicate the potential for using grazing sheep to control wheat stem sawfly infestations in cereal grain production systems.

Incorporating sheep into dryland grain production systems: II. Impact on changes in biomass and weed density

Weed control in fallow management to conserve soil moisture and nutrients is the largest variable cost to dryland grain production. Our objective was to compare burning, grazing, tilling, trampling and clipping wheat stubble fields on changes in total aboveground biomass and weed density. Treatments were evaluated in three experiments using a randomized complete block design for each experiment with four replications at each site. Contrasts statements were used to make pre-planned comparisons. For experiment 1, treatments were fall tilled, fall grazed, spring grazed, fall and spring combined (Fall/Spr) grazed, and an untreated control. For grazing treatments, five mature ewes were confined with electric fence to 111 m 2 plot for 24 h for fall and spring resulting in a stocking rate of 452 sheep day/ha. For Fall/Spr the stocking rate was 904 sheep day/ha. For experiment 2, treatments were fall grazed, fall burned, fall tilled, and an untreated control. In experiment 3, treatments were fall trampling by sheep, spring trampling by sheep, fall and spring combined (Fall/Spr) trampling by sheep, stubble hand clipped to a height of 4.5 cm, and an untreated control. Trampling treatments were applied at the same stocking rates as grazing treatments but sheep were muzzled to prevent intake. Data were collected in the fall, prior to treatment imposition, and spring, after treatments had been removed. Post treatment biomass and weed density were greater ( P < 0.05) in either control or tilled plots when compared to grazed plots. Post treatment biomass and weed density were greater ( P < 0.01) for control than burned plots. Post treatment biomass, weed density, and percent change in these variables, did not differ ( P > 0.08) between burned and tilled, and burned and grazed treatments. These results indicate the potential for using grazing sheep as a component in fallow management to reduce biomass and control weeds.

Incorporating sheep into dryland grain production systems: III. Impact on changes in soil bulk density and soil nutrient profiles

Changes in soil bulk density and soil nutrient profiles are a major concern of dryland grain producers considering grazing sheep on cereal stubble fields. Our objective was to compare burned, grazed, tilled, trampled and clipped wheat stubble fields on changes in soil bulk density and soil nutrient profiles. Treatments were evaluated in a series of three experiments using a randomized complete block design and four replications at each site. Contrast statements were used to make pre-planned comparisons among treatments. For Experiment 1, treatments were fall tilled, fall grazed, spring grazed, fall and spring combined ( Fall/ Spr) grazed, and an untreated control. Five mature ewes were confined with electric fence to a 111 m 2 plot for 24 h for fall and spring grazed plots resulting in a stocking rate of 452 sheeps d/ha. For Fall/Spr, the stocking rate was 904 sheeps d/ha. For Experiment 2, treatments were fall grazed, fall burned, fall tilled, and an untreated control. In Experiment 3, treatments were fall trampling by sheep, spring trampling by sheep, fall and spring combined (Fall/ Spr) trampling by sheep, hand clipping to a stubble height of 4.5 cm, and an untreated control. Trampling treatments were done at the same stocking rates as grazing treatments but sheep were muzzled to prevent intake. In Experiment 1, post-treatment organic matter tended to be greater ( P = 0.09) in the mean of the grazed treatments than control plots. In all of the experiments, change in soil bulk density, and soil nutrient profiles did not consistently differ ( P > 0.07) among treatments in any manner that would suggest a detrimental impact of grazing sheep on small grain residue. These results indicate a strong potential for grazing sheep on grain stubble without adversely impacting soil bulk density or nutrient profiles.

Survey of Winter Wheat (Triticum aestivum) Stubble Fields Sprayed with Herbicides in 1998: Cultural Practices1

A survey of 174 fields was conducted during August and September of 1998 to investigate effects of cultural and herbicide practices on postharvest weed control in winter wheat stubble fields across western and southern Nebraska. Seventy-four percent of the fields were seeded at rates of 67 to 100 kg/ha, with 60% of the wheat seeded in rows spaced 25 cm apart. Wheat seeded in east–west rows contained 98% more stinkgrass and 82% more tumble pigweed than wheat seeded in north–south rows. Sixty-nine percent of winter wheat stubble fields were rated excellent for weed control. Postharvest weed control with herbicides was not affected by row spacing. In western Nebraska, density of tumble pigweed and Russian thistle was greater when wheat seeding rate was 50 kg/ha than at higher seeding rates. Short-stature winter wheat cultivars had greater densities of Pennsylvania smartweed and toothed spurge than taller cultivars. The most common winter wheat cultivars were ‘Arapahoe’ (34%) and ‘Alliance’ (17%). Weed control was positively correlated with number of winter wheat stems per square meter (r = 0.22**). Density of several weed species was greater in fields seeded with a disk than with a hoe drill. The most common crop rotations sampled were winter wheat–corn–fallow (50%), winter wheat–fallow (18%), and winter wheat–corn–soybean (13%). Winter wheat yields and wheat stem densities were greater and weed density was less when winter wheat was seeded after an 11- to 14-mo fallow period rather than a 0- to 5-mo period.Nomenclature: Green foxtail, Setaria viridis (L.) Beauv. #3 SETVI; kochia, Kochia scoparia (L.) Schrad. # KCHSC; Pennsylvania smartweed, Polygoncum pensylvanicum P. # POLPY; Russian thistle, Salsola iberica Sennen & Pau # SASKR; stinkgrass, Eragrostis cilianensis (All.) E. Mosher # ERACN; toothed spurge, Euphorbia dentata Michx. # EPHDE; tumble pigweed, Amaranthus albus L. # AMAAL; corn, Zea mays L.; soybean, Glycine max (L.) Merr.; winter wheat, Triticum aestivum L.Additional index words: Atrazine, crop rotations, ecofallow, ecofarming, glyphosate, no-till, weed management.Abbreviations: W–C or Sor, winter wheat–corn or sorghum; W–C–F, winter wheat–corn–fallow; W–C–Soy, winter wheat–corn–soybean; W–C–Spgr, winter wheat–corn–spring grains; W–F, winter wheat–fallow; W–W, winter wheat–winter wheat.

Multitemporal monitoring of soil moisture with RADARSAT SAR during the 1997 Southern Great Plains hydrology experiment

Multitemporal RADARSAT Synthetic Aperture Radar (SAR) imagery was evaluated for monitoring soil moisture during the Southern Great Plains 1997 Hydrology Experiment (SGP97). Over the 1-month experiment a total of 10 RADARSAT (C-band; 5.3GHz; HH polarized) acquisitions were obtained. After co-registration of the images, the dependence of the backscattering coefficient (σ) on incidence angle (θ) was evaluated. An angular correction scheme was applied to the data and the correlation of a values with volumetric soil moisture measurements was determined. A high positive correlation between the two was observed for wheat stubble fields, whereas no correlation could be observed for pasture fields. A change detection approach yielded a correlation of soil moisture changes to σ changes for wheat stubble fields, indicating the potential of this method for soil moisture monitoring.

A two‐layer canopy compensation point model for describing bi‐directional biosphere‐atmosphere exchange of ammonia

AbstractA new resistance model is described to interpret the biosphere‐atmosphere exchange fluxes of ammonia (NH3) with vegetation, and compared with previous modelling approaches for NH3. The new model constitutes an extension of an existing one‐layer canopy compensation point model: in addition to bi‐directional foliar stomatal exchange and deposition to leaf cuticles, the model treats NH3 emission from a ground layer. This may originate from fertilizer evaporation, the soil or decomposing plant parts. The emission potentials of the foliage and ground surface are given by the NH3 gas concentrations at equilibrium with the ammonium (NH+4) concentration in the apoplastic fluid or soil solution. From these concentrations, as well as the transfer resistances of the different exchange pathways, the net compensation point of the canopy (Xc) may be derived. The net flux is determined by the relative magnitude of Xc and the NH3 air concentration above the vegetation. The two‐layer canopy compensation point is applied to: (i) an oilseed rape canopy, in which NH3 emission from decomposing leaf litter at the ground surface presents a second major source; and (ii) a wheat stubble field, in which emission from the soil contributes significantly to the net exchange. For both canopies, the model performance is contrasted with the single‐layer Xc model, which is not able to reproduce the temporal patterns of exchange. The two‐layer model is proposed as the optimum compromise between simplicity and accuracy, capable of describing bi‐directional NH3 exchange in atmospheric transport models over a very wide range of vegetation types.

Acoustical Properties of Farmland

Although many measurements have been made of the propagation of sound over grassland, there are relatively few data over cultivated surfaces. The propagation of sound over an absorbing surface is influenced by the impedance of the surface and the locations of the source and the receiver. A reduction in ground impedance can increase the rate of attenuation of A-weighted sound levels due to broad-band sources near to the ground. Measurements of complex excess attenuation at 1 m from a point source have been used to deduce the acoustical impedance of a variety of farmland surfaces including arable land. These data suggest that farmland surfaces have lower impedance values than those assumed typical of grass-covered surfaces in noise prediction schemes. Spectra of the difference in levels measured at vertically separated microphones at distances of 30 and 44 m from a loudspeaker over four cultivated surfaces are presented. The differences between spectra measured over subsoiled or ploughed ground and those obtained over relatively undisturbed surfaces are consistent with predictions that take into account the effective impedance of rough porous surfaces. The rates of attenuation of A-weighted broad-band sound over an oilseed rape crop, and over ploughed and undisturbed portions of a wheat stubble field at ranges up to 50 m are found to be greater than predicted by an empirical ISO method. A simple semi-empirical model that uses a single ground parameter is found to give better agreement with these data.

BELTS VS TIRES, BELTS VS BELTS, TIRES VS TIRES

Tractive performance comparisons among two different width rubber belt tracks, 46 cm (18 in.) and 81 cm(32 in.) wide, and two different size rear tires, 710/70R38 and 18.4R46, were made on two different surface conditions.The belts were tested on a Caterpillar 55 tractor equipped with the Mobil-trac system and the tires on a John Deere8400 mechanical front-wheel-drive (MFWD) tractor. The performance tests were completed on two surfaces, one being anon-tilled wheat stubble field and the second, the wheat stubble field tilled approximately 23 cm (9 in.) deep with a Nobleblade sweep. Performance comparisons using tractive efficiency, dynamic traction ratio, and slip were made. Results ofthese performance comparisons between the belts and tires indicate that, in general, the belts performed better. Theperformance differences between the two belt widths were less defined. The performance differences between the two tiressuggests that the narrower tire had a slight traction advantage.

Survival of Wheat Streak Mosaic Virus in Grass Hosts in Kansas from Wheat Harvest to Fall Wheat Emergence

Field samples of annual and perennial grasses were tested to determine which can be alternate hosts to wheat streak mosaic virus (WSMV) and can survive and sustain the virus from wheat harvest to fall wheat emergence in Kansas. Sites sampled included Conservation Reserve Program (CRP) hectares, government set-aside fields, wheat stubble fields, and waterways. Samples were collected in August of 1988 and at four approximately monthly intervals in 1989 and were tested for the virus by indirect ELISA. None of the perennial grasses sampled were infected, but five annual grass species - Setaria viridis, S. taberi, Eriochloa contracta, Echinochloa crusgalli, and Panicum capillare - plus volunteer wheat were infected throughout this period (.)

Axle Power Distribution for a Front-Wheel Assist Tractor

ABSTRACT A tractor equipped with a mechanical front-wheel assist was performance tested in the two- and four-wheel drive modes. Total tractor mass and static ballast distribution was identical when comparing performance differences between the two drive modes. Power demand for drawbar pull, slip and motion resistance of a mechanical front wheel drive tractor operated in the two- and four-wheel drive mode were compared on a wheat stubble field before and after plowing. The front-wheel assist tractor operated in the four-wheel drive mode had lower slip and motion resistance losses and higher drawbar pull than when operated in the two wheel drive mode.

Transformations of Fall‐Applied Nitrogen‐15‐Labelled Fertilizers

AbstractIn conjunction with field studies on gaseous losses of nitrogen, the transformations of fall‐applied 15N‐labelled KNO3 and urea (with and without nitropyrin) were studied in black and dark brown Chernozemic (Typic Udics and Typic Haploborolls) soils during 1980–81 and 1981–82. The amount of fall‐applied N which could not be accounted for in the following spring ranged from 25 to 33% (2 sites) for KNO3 and only 10 and 5% from urea without and with nitropyrin, respectively. These losses occurred during the fall (before the soil was frozen) and in the following spring (after soil thaw) and were primarily due to denitrification. Nitrification of NH+4‐N from applied urea occurred at a slow rate during the cool late fall until freeze‐up and commenced again in early spring when the soil warmed up. Application of nitrapyrin in conjunction with urea delayed nitrification as well as downward movement of fertilizer N in the soil profile and was effective in decreasing the denitrification losses. Immobilization of fertilizer N was minimum under fallow conditions (7%) but ranged from 15 to 21% and 24 to 26% of the applied N as KNO3 and urea, respectively, in wheat stubble fields. Nitrapyrin did not affect the immobilization of fertilizer N or the amount of fertilizer N found in the microbial‐biomass.