Effect of variable rate seeding on winter wheat seedbed and germination parameters using soil apparent electrical conductivity

Due to the variability of soil characteristics in the field and the rising prices of high-quality seeds, farmers are increasingly interested in applying a system of precision variable rate seeding (VRS), which makes it easier to manage risks in crop production and allows to ensure the profitability of the farm. Most modern seed drills are equipped with a hydraulic or electric drive and a terminal in the tractor cabin, allowing farmers to apply VRS. The aim of this study was to determine the most appropriate seeding rate of winter wheat according to the measured apparent soil electrical conductivity (ECa) in the field, to investigate the uniformity of seed placement by layers in the soil and to evaluate the germination dynamics of winter wheat. Precision seeding was performed using a VRS map, generated from soil ECa data obtained by field surface scanning using the ECa device EM-38 MK2. Winter wheat seeding was implemented with a direct seed drill. The research was carried out by measuring the parameters of winter wheat seedbed and germinated plants, including the number and distribution of seeds in soil layers of different depths, germination, tillering. Field research was performed with 3 treatments and 4 repetitions (1 - uniform rate seeding; 2 - VRS; 3 - VRS + variable rate fertilisation (VRF)). The results of the research showed a direct relationship between the soil ECa and the depth of seed placement. Most seeds were inserted at medium depths (15-30 mm), except in the soil management zone, where ECa was highest (28.8 mS center dot m(-1)). In this area, most seeds (50.7%) were inserted shallowly up to 15 mm. The experimental results of seeding studies showed that using the VRS and VRS + VRF methods in all soil zones the germination of winter wheat was similar, while seeding at the uniform rate yielded significant differences between individual soil zones

The Substantiation of Concave Crossbars Design for Corn Ear Shelling

Eksperimentiniai tyrimai atlikti 2016–2019 metais Žemės ūkio mašinų technologinių procesų tyrimų laboratorijoje stacionariu tangentiniu stendu, kurio kūlimo būgno skersmuo yra 0,8 m. Pasirengiant tyrimams, buvo nustatytas 32 mm arba 35 mm tarpas tarp kūlimo būgno spragilo ir burbuolės apačios (stalo paviršiaus). Būgno spragilo linijinis greitis (12; 13; 14; 15; 16; 17 m s-1) buvo nustatytas įtampos dažnio keitikliu. Tyrimai atlikti su šešiomis skirtingų formų (8; 10 ir 12 mm aukščio) skersinėmis juostomis, kurios montuojamos stende. Tyrimų rezultatai parodė, kad skersinės juostos darbinio paviršiaus forma sąlygoja kukurūzų grūdų sužalojimą. Kuliant sausas kukurūzų burbuoles, grūdų sužalojimą galima sumažinti (nesumažinant grūdų separacijos nuo burbuolės šerdies) javų kombaino pobūgnyje įprastas užapvalinto darbinio paviršiaus skersines juostas pakeitus į tokias, kurių paviršius yra nuožulnus (28°–36° posvyrio kampo).The experimental research was conducted in 2016–2019 at the Laboratory for Analysis of Technological Processes of Agricultural Machinery using a stationary tangential single-cylinder threshing unit with one rasp bar and the cylinder diameter of 0.8 m. The crossbars of six different designs (8; 10; 12 mm height) were manufactured for the research. The clearance between the threshing cylinder rasp bar and bottom of concave crossbar (bottom of corn ear) was from 32 mm and 35 mm. The linear speed of rasp bar (12; 13; 14; 15; 16; 17 m s-1) was set by a variable frequency drive. The studies of corn ears threshing have shown that the shape of the concave cross bars surface have a significant influence on the grain damage while grain detachment from the cobs remains similar. For dry corn ear threshing it would be reasonable to use the concave equipped with oblique cross bars (surface angle 28° – 36°).Žemės ūkio inžinerijos fakultetasŽemės ūkio inžinerijos ir saugos instituta

The influence of concave crossbar design on corn ear shelling efficiency and grain damage

Eksperimentiniai tyrimai atlikti 2018 metais Žemės ūkio mašinų technologinių procesų tyrimų laboratorijoje naudojantis stacionariu tangentiniu kūlimo stendu, kurio kūlimo būgno skersmuo yra 0,8 m. Pasirengiant tyrimams, buvo nustatytas 32 mm tarpas tarp kūlimo būgno spragilo ir burbuolės apačios (stalo paviršiaus). Būgno spragilo linijinis greitis (15,0 m s-1) buvo nustatytas įtampos dažnio keitikliu. Tyrimai atlikti su keturiomis skirtingų formų (6 mm aukščio) skersinėmis juostomis, kurios montuojamos stende. Tyrimų rezultatai parodė, kad skersinės juostos darbinio paviršiaus forma sąlygoja kukurūzų grūdų sužalojimą. Kuliant sausas kukurūzų burbuoles grūdų sužalojimą galima sumažinti (nesumažinant grūdų separacijos nuo burbuolės šerdies) javų kombaino pobūgnyje įprastas užapvalinto darbinio paviršiaus skersines juostas pakeitus į tokias, kurių paviršius yra nuožulnus (28° posvyrio kampo)The experimental research was conducted in 2018 at the Laboratory for Analysis of Technological Processes of Agricultural Machinery using a stationary tangential single-cylinder threshing unit with one rasp bar and the cylinder diameter of 0.8 m. The crossbars of four different designs (6 mm height) were manufactured for the research. The clearance between the threshing cylinder rasp bar and bottom of concave crossbar (bottom of corn ear) was 32 mm. The linear speed of rasp bar (15 m s-1) was set by a variable frequency drive. The studies of corn ears threshing have shown that the shape of the concave cross bars surface have a significant influence on the grain damage while grain detachment from the cobs remains similar. For dry corn ear threshing it would be reasonable to use the concave equipped with oblique cross bars (surface angle 28°)Vytauto Didžiojo universitetasŽemės ūkio akademij

The influence of concave crossbars design on corn ear shelling efficiency during rasp bars impact

Eksperimentiniai tyrimai atlikti 2017 metais Žemės ūkio mašinų technologinių procesų tyrimų laboratorijoje stacionariu tangentiniu kūlimo stendu, kurio kūlimo būgno skersmuo buvo 0,8 m. Prieš pradedant tyrimus, buvo nustatytas 24 mm tarpas tarp kūlimo būgno spragilo ir pobūgnio skersinės juostos. Būgno spragilo greitis (10.47 m s-1; 12.57 m s-1; 14.66 m s-1) buvo nustatytas įtampos dažnio keitikliu. Tyrimams buvo suprojektuotos ir pagamintos penkių skirtingų formų skersinės juostos, kurios montuojamos stende. Geriausi rezultatai gauti naudojant įstrižas 28–36° juostas, kurių plotis 11–15 mm, o aukštis – 8 mm, kai spragilo greitis siekia 14,66 m s-1The experimental research was conducted in 2017 at the Laboratory for Analysis of Technological Processes of Agricultural Machinery using a stationary tangential single-cylinder threshing unit with one rasp bar and the cylinder diameter of 0.8 m. The crossbars of five different shapes to be installed into the threshing unit were designed and manufactured for the research. The clearance between the threshing cylinder rasp bar and concave crossbar was 24 mm. The speed of rasp bars (10.47 m s-1; 12.57 m s-1; 14.66 m s-1) was set by a variable frequency drive. The tests have de-monstrated that the oblique crossbars shape (tilt angle 28–36°; width 11–15 mm; height 8 mm) has a positive effect on grain detaching from cob during threshingVytauto Didžiojo universitetasŽemės ūkio akademij