Soybean Harvest Research Articles

Variable-rate in corn sowing for maximizing grain yield

Sowing density is one of the most influential factors affecting corn yield. Here, we tested the hypothesis that, according to soil attributes, maximum corn productivity can be attained by varying the seed population. Specifically, our objectives were to identify the soil attributes that affect grain yield, in order to generate a model to define the optimum sowing rate as a function of the attributes identified, and determine which vegetative growth indices can be used to predict yield most accurately. The experiment was conducted in Chapadão do Céu-GO in 2018 and 2019 at two different locations. Corn was sown as the second crop after the soybean harvest. The hybrids used were AG 8700 PRO3 and FS 401 PW, which have similar characteristics and an average 135-day cropping cycle. Tested sowing rates were 50, 55, 60, and 65 thousand seeds ha−1. Soil attributes evaluated included pH, calcium, magnesium, phosphorus, potassium, organic matter, clay content, cation exchange capacity, and base saturation. Additionally, we measured the correlation between the different vegetative growth indices and yield. Linear correlations were obtained through Pearson’s correlation network, followed by path analysis for the selection of cause and effect variables, which formed the decision trees to estimate yield and seeding density. Magnesium and apparent electrical conductivity (ECa) were the most important soil attributes for determining sowing density. Thus, the plant population should be 56,000 plants ha−1 to attain maximum yield at ECa values > 7.44 mS m−1. In addition, the plant population should be 64,800 plants ha−1 at values < 7.44 mS m−1 when magnesium levels are greater than 0.13 g kg−1, and 57,210 plants ha−1 when magnesium content is lower. Trial validation showed that the decision tree effectively predicted optimum plant population under the local experimental conditions, where yield did not significantly differ among populations.

ЕФЕКТИВНІСТЬ ОСНОВНОГО ОБРОБІТКУ ҐРУНТУ ТА МІНЕРАЛЬНОГО ЖИВЛЕННЯ У ВИРОЩУВАННІ СОЇ НА ЗРОШЕННІ

In the article the brought results over of experimental researches of influence of different methods and depth of soil basic tillage and doses of mineral fertilization on agrophysical properties and productivity of soybean. A purpose of researches is establishment of the most effective methods of soil basic tillage and doses of application of mineral fertilizers at growing of soybean in row croprotation on the irrigation of south of Ukraine and their influence on a height and development of plants, forming of harvest and quality of seed. During an experiment used the field, in-gravimetric, visual, laboratory, calculation-comparative, mathematically-statistical methods with the use of confessedly methods and methodical recommendations. For determination of efficiency of action of soil basic tillage and doses of fertilizers on the productivity of soybean five variants of methods of basic tillage were stopped up and three variants of fertilizer systems: organic and two organo-mineral with doses bringing of mineral fertilizers - N30P60, N60P60 on a background of post harvesting bits and pieces of cultures of crop rotation and optimal mode of irrigation. Results. The changes of agrophysical properties happened under act of the systems of soil basic tillage, nourishing mode, that stipulated creation of different terms for a height and development of culture and forming of harvest. The productivity of seed of soybean at plowing on a 25-27 cm averaged for five years on a background the dose of fertilizers of N60P60 of 4,22 t/ha. At the combined tillage which united disk loosening on a 14-16 cm with slotting on a depth a 38-40 cm, 4,12 t/ha of seed of soybean is got in the system of differentiated-1 soil tillage. On the average on a factor B (system of fertilizer), the productivity of seed of soybean at organic system of fertilize made 2,38 t/ha. Bringing of dose N30P60 assisted the height of harvest on 0,84 t/ha, and N60P60 on 1,39 t/ha, or on 35,2 and 58,4% accordingly. Conclusion. In the short row crop rotation on the irrigated lands of south of Ukraine the most favorable terms for a height, development and forming of harvest of soybean on dark-chestnut soils are created in the systems of plowing basic soil tillage with the turn of layer or differentiated- 1 tillage with the deep loosening under soybean or shallow on a background slotting on a depth a 38-40 cm under a previous culture.

Effect of row spacing and herbicide programs for control of glyphosate-resistant Palmer amaranth (Amaranthus palmeri) in dicamba/glyphosate-resistant soybean

AbstractGlyphosate-resistant (GR) Palmer amaranth is one of the most difficult to control weeds in soybean production fields in Nebraska and the United States. An integrated approach is required for effective management of GR Palmer amaranth. Cultural practices such as narrow row spacing might augment herbicide efficacy for management of GR Palmer amaranth. The objectives of this study were to evaluate the effect of row spacing and herbicide programs for management of GR Palmer amaranth in dicamba/glyphosate-resistant (DGR) soybean. Field experiments were conducted in a grower’s field with a uniform population of GR Palmer amaranth near Carleton, Nebraska, in 2018 and 2019. Year-by-herbicide program-by-row spacing interactions were significant for all variables; therefore, data were analyzed by year. Herbicides applied PRE controlled GR Palmer amaranth ≥95% in both years 14 d after PRE (DAPRE). Across soybean row-spacing, most PRE followed by (fb) early-POST (EPOST) herbicide programs provided 84% to 97% control of Palmer amaranth compared with most EPOST fb late-post (LPOST) programs, excluding dicamba in single and sequential applications (82% to 95% control). Mixing microencapsulated acetochlor with a POST herbicide in PRE fb EPOST herbicide programs controlled Palmer amaranth ≥93% 14 d after EPOST and ≥96% 21 d after LPOST with no effect on Palmer amaranth density. Interaction of herbicide program-by-row spacing on Palmer amaranth control was not significant; however, biomass reduction was significant at soybean harvest in 2019. The herbicide programs evaluated in this study caused no soybean injury. Due to drought conditions during a majority of the 2018 growing season, soybean yield in 2018 was reduced compared with 2019.

Impact of Wheat on Soybean Cyst Nematode Population Density in Double-Cropping Soybean Production.

Double-cropping is defined as producing more than one crop on the same parcel of land in a single growing season. It is reported to have many benefits when incorporated in cropping systems, including improving soil health. In some double-cropping systems, soybean is planted following winter wheat. The soybean cyst nematode (SCN) (Heterodera glycines Ichinohe) is a major soybean pathogen, and several reports suggest suppressive effects of wheat on SCN populations. Field trials were conducted from 2017 to 2018 to investigate the effect of wheat on SCN populations in double-cropping soybean. Nine fields with three levels of initial SCN populations (low, moderate, and high) were selected in Illinois. Wheat was planted in strips alternating with strips-maintained weed-free and under fallow over winter and early spring. Soybean was planted in all strips after wheat harvest. SCN egg densities were acquired at four time points: wheat establishment, post-wheat/pre-soybean, mid-soybean (R1 growth stage or beginning of flowering), and post-soybean harvest. Wheat strips reduced SCN egg densities compared with fallow strips at the R1 stage (−31.8%) and after soybean harvest (−32.7%). Double-cropping soybean with wheat has the potential to suppress SCN field populations and is a system with the potential to provide additional farm income. This study is meant to be a first step toward a better understanding of the mechanisms that govern the suppression of SCN by wheat.

78 Winter Hardy Small Cereal Cover Crops for Grazing and Silage in Nebraska

Abstract Cereal rye, winter wheat, and winter triticale are commonly planted cover crops in corn and soybean systems and have the potential to provide early spring grazing. The three cover crops differ in growth pattern. Therefore, a study was conducted to investigate the grazing potential of the three species, including the timing of the start of grazing and nutritive value of forage as measured by growing calf gain. A 7.3 hectare field was divided into 9, 0.81-hectare paddocks. Three paddocks (n = 3 replicates per treatment) were randomly assigned to each treatment: variety not stated cereal rye, Pronghorn winter wheat, or NT11406 triticale. Pastures were seeded in Mid-September following early maturity soybean harvest and received no fertilizer. Fifty-four steers (305 kg SD ± 5 kg) were stratified by weight and assigned to one of nine groups which were then assigned to a paddock. The paddocks were split in half. Steers were turned out when forage reached a 12.7 cm height and rotated to the other half once the occupied half reached 5 cm. Grazing began April 3 for rye pastures and April 9 for triticale and wheat pastures. Two groups of cattle grazing rye were pulled April 29 due to limited forage. All remaining cattle were pulled May 8 to allow for soybean planting. Throughout the grazing period pre and post-graze biomass did not differ (P ≥ 0.36) among treatments. Average daily gain did not differ among treatments (P = 0.88) averaging 1.79, 1.86, 1.84 kg/day for rye, wheat and triticale, respectively. Likewise, gain per hectare did not differ (P = 0.80) among treatments with 378, 399, 394 kg/ha for rye, wheat, and triticale, respectively. Rye offered grazing a full week before triticale and wheat, but all three small grain cereal species resulted in desirable animal performance.

An experimental and finite element analysis of the characteristics of soybean grain compression damage

AbstractDuring mechanized harvesting, the compression of soybean grains is the main form of crushing caused by the interaction between the operating components and the soybean grains; the resulting damage characteristics of the grains are not well understood. Using Zhengdou 1307 as test materials, the characteristics of stress distributions under different moisture contents soybean grains in the horizontal, lateral, and vertical positions were measured and analyzed, the process of compressive damage was observed, and the damage characteristics due to compression forces were obtained. The test results show that the forced form and compressive displacement of a soybean grain is related to the magnitude of the compressive force, and the location of the stress concentration moves toward the contact, as the contact area decreases, breaking force decreases with increasing moisture content. The grain is subjected to the highest pressure when placed flat, and cracks along the vertical line of the hilum upon rupture. When placed laterally and vertically, the damage to the grain due to a compressive force is mainly from the separation of the two cotyledons.Practical applicationsThe crushing rate is an important indicator to measure the harvest quality of the soybean combine. The mechanical properties of soybean grains are an important factor affecting the crushing rate. In the process of mechanized soybean harvesting, the compression of soybean grains is the main form of crushing caused by the interaction between working parts and soybean grains, but the characteristics of soybean grains damaged by compression are not clear. This study provides a reference for the analysis of soybean damage during the harvesting, transporting, storing, and other stages by studying the damage characteristics of soybean grains, and provides certain ideas for the study of other grain damage characteristics.

Nitrogen fertilization on soybean crop over straw of forage sorghum intercropped with Urochloa ruziziensis

The experiment was carried out to evaluate the influence of N on the agronomic characteristics of soybean crop under no-tillage system over forage sorghum intercropped with Urochloa ruziziensis and on straw degradation. Four treatments (nitrogen doses) were used: 0; 20; 40 and 60 kg of N ha-1. N were applied at V3-V4 stage, using ammonium nitrate as the N source, containing 30% N. The experimental design was a randomized block design with four replications. The evaluation of dry matter quantity of forage sorghum and U. ruziziensis straw was carried out before the sowing of forage sorghum and U. ruziziensis and after soybean harvest. The soybean crop parameters evaluated were, as follows: first pod insertion height and plant height, final stand ha-1 and grain yield ha-1. Evaluations were performed at the soybean crop harvest. Nitrogen fertilization did not influence the straw decomposition of U. ruziziensis and forage sorghum nor the first pod insertion height, plant height and final stand ha-1 of soybean crop. Nevertheless, fertilization showed a quadratic behavior in the 2015/2016 crop in relation to grain yield, with a reduction in yield at doses greater than 21 kg of N ha-1, and a linear increase in the 2016/2017 crop. Key words: Ammonium nitrate, Glycine max L., no-tillage.

Detecting Recent Crop Phenology Dynamics in Corn and Soybean Cropping Systems of Kentucky

Accurate phenological information is essential for monitoring crop development, predicting crop yield, and enhancing resilience to cope with climate change. This study employed a curve-change-based dynamic threshold approach on NDVI (Normalized Differential Vegetation Index) time series to detect the planting and harvesting dates for corn and soybean in Kentucky, a typical climatic transition zone, from 2000 to 2018. We compared satellite-based estimates with ground observations and performed trend analyses of crop phenological stages over the study period to analyze their relationships with climate change and crop yields. Our results showed that corn and soybean planting dates were delayed by 0.01 and 0.07 days/year, respectively. Corn harvesting dates were also delayed at a rate of 0.67 days/year, while advanced soybean harvesting occurred at a rate of 0.05 days/year. The growing season length has increased considerably at a rate of 0.66 days/year for corn and was shortened by 0.12 days/year for soybean. Sensitivity analysis showed that planting dates were more sensitive to the early season temperature, while harvesting dates were significantly correlated with temperature over the entire growing season. In terms of the changing climatic factors, only the increased summer precipitation was statistically related to the delayed corn harvesting dates in Kentucky. Further analysis showed that the increased corn yield was significantly correlated with the delayed harvesting dates (1.37 Bu/acre per day) and extended growing season length (1.67 Bu/acre per day). Our results suggested that seasonal climate change (e.g., summer precipitation) was the main factor influencing crop phenological trends, particularly corn harvesting in Kentucky over the study period. We also highlighted the critical role of changing crop phenology in constraining crop production, which needs further efforts for optimizing crop management practices.

Estimated losses in soybean (Glycine max (L.) Merril) harvest according to the speed and rotation of the trail system

The soybean crop (Glycine max. (L.) Merril) shows strong participation in the Brazilian economy. Therefore, the aim of the present study was to quantify the losses in the cutting and feeding platform and in the trail system in mechanized soybean harvest by analyzing different speed and rotation adjustments of the trailing cylinder. The experiment was carried out in a commercial soybean plot on a farm located in the municipality of Brejo (MA), during the 2017/2018 harvest. The harvester evaluated was a Case IH 8120, with a maximum power of 34.2 kW, axial flow system, and 12.2-m platform equipped with a conveyor system (draper). The experiment was conducted in two different areas. Area 1 was planted with the Brasmax® Opus (BMX Opus) cultivar, while area 2 was cultivated with the BRS 9383 cultivar. The treatments consisted of three machine speeds (4 km h-¹, 6 km h-¹, and 7 km h-¹), associated with the rotation levels of 500 rpm and 800 rpm in the trail system. The experimental design used was randomized blocks in a 3 x 2 factorial arrangement, with four replications. For the BMX Opus cultivar, harvest losses did not influence the travel speeds and rotations evaluated in the experiment due to the marked instability within the treatments. The BRS 9383 cultivar showed satisfactory results at a speed of 4 km h-1 combined with a rotation of 800 rpm, which obtained acceptable numbers for the soybean harvest (54.09 kg ha-1).

Potensi Peningkatan Luas Panen, Produksi, Dan Produktivitas Kedelai Di Jawa Barat

This study aims to identify the development of harvest area, production, and productivity of West Java soybeans during the period 2004-2005, the effect of harvest area on soybean production and grouping districts in West Java based on harvest area and soybean productivity. The analytical tools used are descriptive statistics, regression analysis, and quadrant analysis. The results showed that the harvest area, production and productivity of West Java soybeans during the period 2004-2015 increase with fluctuating growth. Soybean harvest area has a very significant effect on soybean production. The results of quadrant analysis show that only Garut and Indramayu districts are in quadrant II, which have high harvest areas and soybean productivity. Bogor and Bekasi districts are in quadrant IV which have very low harvest area and soybean productivity, while the other 14 districts are in quadrant I with high soybean productivity but low harvest area.

Nitrogen has a greater influence than phosphorus on the diazotrophic community in two successive crop seasons in Northeast China

Fertilizer-induced changes in soil nutrients regulate nitrogen (N) fixation in the terrestrial biosphere, but the influences of N and phosphorus (P) fertilization on the diazotroph communities in successive crop seasons were unclear. In this study, we assessed the effects of N and P (high vs. low doses) on the abundance and structure of N2-fixation communities after wheat and soybean harvest in a long-term (34 and 35 years) fertilization experiment. In both seasons, long-term N addition significantly decreased the abundance of nifH genes and 16S rDNA; in addition, high doses of N and P fertilizer decreased the richness of diazotrophs, whereas low doses did not. The proportion of the dominant genus, Bradyrhizobium, in the soybean season (86.0%) was higher than that in the wheat season (47.9%). Fertilization decreased diazotroph diversity and the relative abundance of Bradyrhizobium in the wheat season, but had insignificant effects in the soybean season. The addition of N, but not P, significantly changed the communities of both diazotrophs (at the genus level) and rhizobia (at the species level) in the two seasons. Soil pH was positively associated with nifH abundance and diazotrophic richness; soil NO3− content was negatively correlated with diazotrophic richness and positively correlated with diversity. Soil pH and NO3− content were the two main drivers shaping the soil diazotrophic community. Overall, long-term inorganic N had a greater influence than P on both diazotrophic abundance and community composition, and diazotrophic diversity was more clearly affected by fertilization in the wheat season than in the soybean season.

Computational model and adjustment system of header height of soybean harvesters based on soil-machine system

With wide distribution and a large planting area, soybeans are an important cash crop in China. Due to the low position of soybean plants, improper control of the header height during harvesting is likely to cause poor harvesting and soil shoveling. To solve such problems, a soybean harvester header-height adjustment system is developed in this study. A profiling mechanism and hydraulic driving system were designed based on a current soybean harvester. The interaction between the soil and the harvester’s profiling mechanism was explored, the force and motion of the profiling mechanism were analyzed, and a relational model between the detection angle of the angular transducer and the rotational angle of the profiling mechanism was built. By analyzing the soil compactness of soybean growing plots, a linear fitting method was used to establish a mathematical model of soil compactness and compacting depth, a computational model of profiling the header height was determined, and an adaptive header-height adjustment system was designed. Evaluation indicators of the soybean harvester header-height adjustment system were constructed and a field harvesting experiment was conducted, whose results show that the absolute error between the average stubble height and the profiling height set by an industrial personal computer (IPC) before the tests was less than 2 mm. The variation coefficients of stubble height in the four groups of tests were 9.3%, 11.6%, 8.5%, and 6.5%, with respective profiling control accuracy of 88%, 86%, 90%, and 92%, ground flatness and soil compactness have little effect on the overall control effect of the control system.

Determination of stripping zones and axle spacing between the cylinders in two-cylinder stripping reaper (header)

Stripping devices become an alternative to harvester-threshers in the harvesting season. The research objective is improvement of harvesting operations, including the introduction of the method of soya stripping. The research showed that the use of a single-cylinder stripping device was not optimal, for harvesting losses exceeded agricultural norms. It was decided to use a two-cylinder scheme. The implementation of this design solution reduced the grain loss rate, but still it was not enough to achieve compliance with the requirements of classical soybean harvesting. For high-quality soybean stripping, it is necessary to calculate the zones of stripping and axle spacing between the first and second stripping cylinders, as well as the profile of the stripping combs. Schemes presented are calculation of the stripping zones and determination of the axle spacing between the cylinders, taking into account their positional relationship in the stripping reaper.

Soybean harvesting using current dedicated headers and adapters

The article describes the basic agrotechnical requirements for soybean combine harvesting. The current model range of adapters and headers used by agricultural producers for harvesting is analyzed. The design features and purpose of the headers and adapters to be used are studied. The results of experimental studies using dedicated soybean harvesting headers manufactured by Rostselmash in the real economic conditions of the Southern Federal District of the Russian Federation and a theoretical calculation of the optimal length of the header table are presented. Studies of combine harvesters from Rostselmash (Nova 340, Vector, TORUM) having various designs of threshers (single-drum; axial-flow) have shown that RSM-181 TORUM 750+ZhSU-900 and RSM-181 TORUM 740+ZhSU-700 combine harvesters have high productivity per hour of the main period equal to 5.20 and 4.80 ha / h respectively. This can be explained by the presence of a large working width header, a high speed of movement and an axial-flow thresher used on the combine. When harvesting long-stalked soybeans, the length of the header table is of great importance, which determines the reliability of the header auger, the uniformity of the plant mass supply to the combine thresher. As a result of theoretical calculations, it was established that the header table length should be L_ht≥0.81 m. Manufacturers of current headers recommend replacing a serial length table with a table having an extended length when harvesting long-stalked soybeans.

Integrated Weed Management Systems to Control Common Ragweed (Ambrosia artemisiifolia L.) in Soybean

As resistance to herbicides limits growers' weed management options, integrated weed management (IWM) systems that combine non-chemical tactics with herbicides are becoming critical. A 2 year integrated weed management (IWM) study was conducted at three locations in VA, USA. The factorial study evaluated: (1) soybean planting date (early or late planted) (2) with or without winter cover (cereal rye/wheat or no cover), and (3) with or without harvest weed seed control (HWSC). Prior to soybean planting in the first year, winter cover resulted in a 22% reduction in common ragweed density compared to no cover. At soybean harvest in the first year, the lowest common ragweed densities were in the late planted plots following winter wheat, and common ragweed aboveground biomass was reduced by 46 and 22% at two locations in late planted compared to early planted soybean. To evaluate the impact of the first year's treatments and HWSC, full season soybeans were planted across the trial in the second year. Prior to soybean planting in the second year, late planting in the first year common ragweed density was reduced by 83% at one location, but significant reductions were not observed elsewhere. When comparing winter cover to no cover, common ragweed densities were reduced by 31 and 49% at two locations and densities were similar at the third location. Harvest weed seed control reduced common ragweed density by 43% at one location compared to the conventional harvest plots but no significant reductions were observed at the other locations or at other rating timings. However, there was a significant location by planting date by winter cover interaction and the overall lowest common ragweed densities (4.1 to 10.3 plants m−2) were in the late planted plots with winter cover. This research indicated that winter cover, late planting, and HWSC can reduce common ragweed populations with late planting being the most influential. Therefore, double-cropping soybean after wheat is likely the most viable means to better control common ragweed using IWM as it combines both winter cover and late planting date.

Effect of single or sequential POST herbicide applications on seed production and viability of glyphosate-resistant Palmer amaranth (Amaranthus palmeri) in dicamba- and glyphosate-resistant soybean

AbstractGlyphosate-resistant (GR) Palmer amaranth is a troublesome weed that can emerge throughout the soybean growing season in Nebraska and several other regions of the United States. Late-emerging Palmer amaranth plants can produce seeds, thus replenishing the soil seedbank. The objectives of this study were to evaluate single or sequential applications of labeled POST herbicides such as acifluorfen, dicamba, a fomesafen and fluthiacet-methyl premix, glyphosate, and lactofen on GR Palmer amaranth control, density, biomass, seed production, and seed viability, as well as grain yield of dicamba- and glyphosate-resistant (DGR) soybean. Field experiments were conducted in a grower’s field infested with GR Palmer amaranth near Carleton, NE, in 2018 and 2019, with no PRE herbicide applied. Acifluorfen, dicamba, a premix of fomesafen and fluthiacet-methyl, glyphosate, or lactofen were applied POST in single or sequential applications between the V4 and R6 soybean growth stages, with timings based on product labels. Dicamba applied at V4 or in sequential applications at V4 followed by R1 or R3 controlled GR Palmer amaranth 91% to 100% at soybean harvest, reduced Palmer amaranth density to as low as 2 or fewer plants m−2, reduced seed production to 557 to 2,911 seeds per female plant, and resulted in the highest soybean yield during both years of the study. Sequential applications of acifluorfen, fomesafen and fluthiacet premix, or lactofen were not as effective as dicamba for GR Palmer amaranth control; however, they reduced seed production similar to dicamba. On the basis of the results of this study, we conclude that dicamba was effective for controlling GR Palmer amaranth and reduced density, biomass, and seed production without DGR soybean injury. Herbicides evaluated in this study had no effect on Palmer amaranth seed viability.

Monitoring of the Combine with Smart Devices in Soybean Harvesting

GIS technology based on real-time smart devices, including GPS devices and sensors will be widely used in agricultural technology. Therefore, this technology is being expected in crop harvesting process. One of the most important processes in soybean cultivation is the efficient use of combines and harvesting without loss of harvest. The grain harvester combine Dominator-130 equipped with GPS receiver and grain level sensor was researched in harvesting the soybean. According to results of experiments, during the harvesting of soybean the grain cleanness in a tank of the combine harvester Dominator-130 made up 95.9 per cent, grain loss in a thresher of combine made up 0.7 per cent, these indexes answer to the demands, however in a reaper of combine harvester the grain loss and damaging of grain were higher than demand. Therefore, it is important to define the optimal technological parameters and working regimes that give opportunity to decrease the loss of grain in the reaper of combine and damaging of grain in the thresher of combine for harvesting the soybean.

The dynamics of soybean seed production and cost structure at farmer level in Konawe and South Konawe Districts, Southeast Sulawesi Province

Research aimed to obtain information on the dynamics of soybean seedling in Southeast Sulawesi Province and its income structure at farmer level. The research was conducted in Landano Sub-district, Konawe Selatan Regency and Pondidaha Sub-district, Konawe Regency which were selected purposively as soybean centers in Southeast Sulawesi. Data collected through interview, observation and documentation studies were analyzed descriptively using cross tabulation, including financial feasibility of soybean seed production. In 2010-2018 there were fluctuations in the planting area and soybean harvest. The highest production and productivity occurred in 2016, experiencing an increase of 21% even though the planting area decreased by 22% from 2015. However in 2016, soybean seed production in Southeast Sulawesi was only able to meet 73.5 % of the need for seeds in the province. Anjasmoro is a preferable variety by farmers because its large seed is suitable for raw material of tofu and tempeh industry. In addition, other characteristics of Anjasmoro interested in are its resistant to falling, leaf rust disease, and pod breaking. Analysis of soybean seed production at breeder farmer level showed that from selling 1,000 kg of seeds, the net profit obtained was IDR 262,100 with an R/C ratio &gt; 1.

Temporal variation and spatial distribution of the pest insect Edessa meditabunda in cotton (Gossypium hirsutum) as an alternative host plant

Cotton is an alternative host for Edessa meditabunda (Hemiptera: Pentatomidae), especially after the soybean harvest in surrounding areas, when large numbers of insects invade cotton fields and damage reproductive structures such as flowers and developing bolls. However, no studies on its occurrence and spatial distribution have been conducted in cotton. Therefore, this study was aimed to assess the temporal variation and spatial distribution of E. meditabunda in the alternative host plant, Gossypium hirsutum. The study was carried out in an area of 1.1 ha planted with cotton that was divided in 64 plots of 169 m2 each, where entire cotton plants were examined weekly and E. meditabunda nymphs and adults were counted. Dispersion rates and theoretical frequency distributions were calculated and analyzed with significance level at 5%. Assessments were carried out from seedling emergence until the appearance of bolls, but E. meditabunda was present only during the reproductive stage of cotton plants. This study detected the dispersal of this stink bug from late-cycle soybean fields to cotton, indicating cotton’s potential as an alternative host plant, providing shelter and food. Based on aggregation indices, the spatial distribution of nymphs and adults in cotton was aggregated at the beginning of the infestation, but tended toward randomness as bolls reached maturity. The occurrence of E. meditabunda in cotton was best described by the Poisson distribution with significance level at 5%.

БОБОВЫЕ ПРЕДШЕСТВЕННИКИ, ОБРАБОТКА ПОЧВЫ И ЗАЩИТА РАСТЕНИЙ В АГРОТЕХНОЛОГИЯХ ЯРОВОЙ ПШЕНИЦЫ СРЕДНЕГО ПОВОЛЖЬЯ

The article presents the results of studies on the evaluation of legume precursors (soybeans, peas, lupin, chickpeas), methods of primary tillage, and plant protection during spring wheat cultivation in the conditions of chernozem soils of the Middle Volga region. Studies have shown that the studied precursors had different growing season duration and water consumption, which provided different water regimes and accumulation of productive moisture in the soil and ultimately affected the productivity of spring wheat. The accumulation of productive moisture in the soil occurs mainly in the autumn, winter, and spring periods; after harvesting peas, no more than 19% of precipitation (28–33 mm) accumulated after harvesting soybeans,lupine, and chickpeas – 29–39% (29–39 mm) until the time of a steady transition of air temperature below 5оC. According to the yield level of spring wheat, the researchers arranged the studied precursors in the following row: after peas – 3,80 t/ha &gt; after chickpeas and lupine – 3,49–3,50 t/ha &gt; after soybeans – 3,45 t/ha. There was an increase in the yield of spring wheat for combined tillage in crop rotation (for the studied crop – soil disking by 10–12 cm + plowing by 20–22 cm) in comparison with minimal tillage by 0,52 t/ha or by 15,6%, and on adaptiveintegrated plant protection by 0,36 t/ha or 10,6% in comparison with the level of standard technologies.The effect of the studied factors on the formation of yield was as follows: tillage – 40,7% &gt; plant protection – 25,3% &gt; precursors – 19,1%. The mentioned variants also increased the quality of spring wheat grain.