Growth and Yield of Soybean and Wheat, and Changes of Soil Properties in a Rotation System Experiment Conducted for 3 Years in an Upland Field Converted from a Paddy Field

Different tillage methods can have varying effects on soil properties and crop quality. Therefore, field experiments were conducted at the Teaching and Research Farm of Landmark University, located in Omu‐Aran, Kwara State. The objectives were to investigate the impacts of various tillage methods on soil characteristics and the growth, yield, mineral and proximate content of soybean (Glycine max (L.) Merr.). Based on these objectives, it was hypothesized that soil properties, growth, yield, mineral and proximate contents of soybean would react differently to different tillage methods. Consequently, experiments were conducted to validate this hypothesis. The treatments were four tillage methods: manual clearing (MC), ploughing (P), ploughing plus harrowing (P + H) and manual ridging (MR), replicated three times in a randomized complete block design. Data on the initial soil properties (bulk density, particle size, pH, organic matter, N, P, K, Ca and Mg), along with the chemical properties of the soil on a per‐plot basis at the end of the experiment, were collected. Additionally, data on soil bulk density, porosity, moisture content and temperature were collected during the vegetative growth of the soybean. Soybean plant height and the number of branches were recorded at the midflowering stage, while grain yield and the number of pods were recorded at harvest. Soybean seeds were later analysed for their mineral and proximate contents using standard methods. P + H resulted in lower soil bulk density than other tillage methods and led to higher growth, yield, proximate and mineral contents of soybean. In MC, bulk density, soil moisture content, soil organic matter, N, P, K, Ca and Mg were significantly higher and temperature lower than in other tillage methods; yet, these advantages did not translate into increased yield and quality due to the higher bulk density. The growth, yield and quality of soybean were significantly influenced by soil bulk density rather than by soil chemical properties. Using the mean of the two sites, relative to MC, P and MR, P + H increased the grain yield of soybean by 41.3%, 24.4% and 13.7%, respectively. These findings underscore the importance of appropriate tillage practices for successful soybean cultivation in similar agroecological zones. For small‐scale operations, MR is suggested, while P + H is recommended for large‐scale soybean production in the studied area. Future studies could include additional variables, such as economic analysis, long‐term soil health impacts or the effects of tillage methods under varying climate conditions.

Weed competition on soybean (Glycine max) growth and yield was expected to be different when managed in an agroforestry system as compared with sole-cropping without trees. Therefore agronomic practices to control weeds might need to be modified in agroforestry systems. We analyzed weed competition effects on soybean growth, grain yield, and yield components at different distances from 4year-old eucalyptus (Eucalyptus benthamii) in an alley cropping system, as well as in a sole-crop system in southern Brazil. Above-ground soybean biomass was collected throughout the growing season and a logistic function was used to model crop growth. Weed above-ground biomass sampled during the soybean cycle, and grain yield and yield components at the end of the growing season were evaluated using regression analysis across positions between tree lines, and results compared to those without influence of trees. Soybean yield components were mostly reduced between tree lines compared with sole-cropping without trees. Soybean growth and yield within the eucalyptus agroforestry system was not affected by weed competition. However, weeds reduced soybean growth and yield in sole-cropping without trees. Reduction in soybean yield in the agroforestry system was rather caused by competition from trees. Therefore, tree interference may limit both weed and soybean growth potential.

Plant growth promoting rhizobacteria are a group of bacteria, that actively colonize plant roots, induce the resistance of plant to pathogen, increase plant growth and yield. Our previous research had showed, that one of rhizobacterial isolates from soybean root effective to promote growth and yield of soybean<em>.</em> To maintain the effectivity of this bacterial isolate during storage, transportation and application, so need to be formulated. The aim of this research was to get the best carrier for formulation to maintain the effectivity of rhizobacterial isolate in storage to promote growth and yield of soybean. This research have used random complete design with 16 treatments and 3 replicates. The treatments were combination of material carrier for formulation of rhizobacterial isolate (peat soil, tapioca flour and coconut water + 1 % palm oil) and time of storage of formula (0, 1, 3, 5 and 7 weeks) and control. The parameter were population density of rhizobacterial isolate on formula, growth development (germination rate, plant height, number of leaves and twigs) generative phase (time of flowering and pod) and yield (weight of seed) of soybean. The results showed that all formulas of rhizobacterial isolate able to increase growth and yield of soybean. The best combination which effective to increase growth and yield of soybean were rizobacteria in peat soil formula and storage for five weeks.

As biochar improves soil fertility and crop productivity, there is a growing interest in it as a resource for sustainable agriculture. Miscanthus sacchariflorus has promising applications in various industries because it has a large amount of biomass. However, research on the agricultural utilization of Miscanthus-derived biochar is insufficient. The aim of this study was to demonstrate the effects of Miscanthus biochar on the soil environment and soybean growth. First, Miscanthus biochar was amended at different levels (3 or 10 tons/ha) in upland soil, after which the soil properties, root development, and yield of soybeans were compared with the control (without biochar). In the soil amended with 10 tons/ha of biochar (BC10), organic matter (OM) and available phosphate increased 1.6 and 2.0 times, respectively, compared with that in the control soil (CON). In addition, the soil dehydrogenase activity increased by 70% in BC10, and 16S rRNA gene sequence analysis revealed that the structure of the microbial community changed after amendment with biochar. The bacterial phyla that differed between CON and BC10 were Acidobacteria and Chloroflexi, which are known to be involved in carbon cycling. Owing to these changes in soil properties, the root dry weight and number of nodules in soybeans increased by 23% and 27%, respectively, and the seed yield increased 1.5-fold in BC10. In conclusion, Miscanthus biochar increased the fertility of soybean-growing soil and consequently increased seed yield. This study is valuable for the practical application of biochar for sustainable agriculture.

Velvetleaf (Abutilon theophrasti Medik.), primarily a cropland weed, exerts adverse impacts on the productivity of various crops, including soybean (Glycine max L.), wheat (Triticum aestivum L.), and maize (Zea mays L.), by hindering their vegetative growth. However, the interference mechanism of velvetleaf on the three crops remains unclear. The inhibitory effect of velvetleaf water extract on the germination and growth of soybean, wheat, and maize was determined in pot experiments and field trials. Four phenolic acids were identified as allelochemicals: protocatechuic acid (PA), gallic acid (GA), chlorogenic acid (CHA), and vanillic acid (VA). These allelochemicals were detected in different parts (leaves, roots, and stems) of velvetleaf, and in the rhizosphere soil of tested crops over the range of 1.19-556.23 μmkg-1 . These allelochemicals were administered in approximate concentrations as in velvetleaf roots and rhizosphere soil, and their effects varied with crop species and velvetleaf parts. The allelochemicals generally had low-dose stimulation and high-dose inhibition effects on the growth of soybean, wheat, and maize. Furthermore, the biomass distribution of these crops was affected by allelochemicals in the soil. In field trials, the allelochemicals significantly (P < 0.05) inhibited the growth of all tested crops over the whole growth period, and PA showed a significant (P < 0.05) inhibitory effect on the yield of soybean, wheat, and maize. GA, PA, CHA, and VA in velvetleaf aqueous extracts were identified as allelochemicals that play an inhibitory role on three crops. © 2022 Society of Chemical Industry.

Winter cover crops effect on soil moisture and soybean growth and yield under different tillage systems

Combined impact of land-use/land-cover and soil property changes on soil erosion in the Yellow River Basin.

ABSTRACTThis study was conducted to evaluate growth characteristics and yield of silage corn hybrids by different planting dates at paddy and upland field. Days to silking by different planting dates at paddy field were 81 days at planting on April 22, 70 days on May 20 and 62 days on June 10, respectively, and they were getting shorter as planting date delayed. There was no significant difference in days to silking between paddy and upland field. Plant height in paddy field was no significant difference between at planting on April 22 and on May 20, and it was shortened sharply at planting on June 10. There was no significant difference in plant height between paddy and upland field. There was no significant difference in lodging by different planting dates in paddy field. There was significant difference in lodging between paddy and upland field(P<0.05). There was no significant difference in stay-green by different planting dates in paddy field, and no significant difference between paddy and upland field. Ear ratios to total dry matter in paddy field were 43% at planting on April 22, 41% on May 20 and 28% on June 10, respectively, and it was lower as planting date delayed. There was no significant difference in ear ratios to total dry matter between paddy and upland field. Fresh yields in paddy field were lower with 14% at planting on May 20 and 32% on June 10 compared to on April 22 as planting date delayed. There was no significant difference in fresh yield between paddy and upland field. Dry matteryields in paddy field were higher with 9% at planting on May 20 and lower with 24% on June 10 compared to at planting on April 22 as planting date delayed. Dry matter yield in paddy field was lower with 9% compared to 1,931kg/10a at planting on April 22. TDN(Total digestible nutrients) yields in paddy field were higher with 5% at planting on May 20 and lower with 28% on June 10 compared to at planting on April 22 as planting date delayed. TDN yield in paddy field was lower with 11% compared to 1,340kg/10a at planting on April 22. (Key words:Paddy field, Silage corn, Planting date, Yield, Dry matter, TDN)

Tropical and subtropical soils typically have high acidity and limited nutrient availability. Surface liming under no‐till systems ameliorates topsoil acidity in the short term, but it is generally slow to neutralize subsoil acidity. A field experiment was conducted in the period from 2016 to 2021 in Parana State, Brazil, on a loamy, kaolinitic, thermic Typic Hapludox to evaluate the effects of surface application of lime combined with the use of monoammonium phosphate (MAP) and elemental S on soil acidity, root growth, plant nutrition and grain yields of wheat ( Triticum aestivum L.) and soybean ( Glycine max. [L.] Merr.) under no‐till. Treatments consisted of a control (no amendments), surface lime (SL), SL + MAP and SL + MAP + elemental S. Applying lime to the soil surface increased soil pH, exchangeable Ca 2+ and Mg 2+ contents and base saturation, as well as reducing Al 3+ content and Al 3+ saturation throughout the soil profile. Such effects were more pronounced in the 0–10 cm layer and occurred to a lesser extent in the 10–100 cm layers. The addition of MAP or MAP + elemental S did not improve the effectiveness of surface liming in alleviating soil acidity throughout the soil profile. The root length per soil surface area to a depth of 100 cm exhibited a strong correlation with wheat yield, but not with soybean yield. Surface liming increased wheat yield by 40% and when lime application was combined with MAP + elemental S, the increase in wheat yield reached 74%. Surface liming resulted in a 36% increase in soybean yield, regardless of the use of MAP and elemental S. Thus, surface application of lime was effective in reducing soil acidity to a 100‐cm depth, regardless of fertilizer application with MAP and MAP + elemental S. The improving effects of surface liming had a more favourable impact on wheat root growth than on soybean root growth, probably because wheat was more affected than soybean by insufficient rainfall during the crop development cycle. Wheat showed a greater yield response to P and S fertilizer application than soybean.

Rice straw and stubble burning is widely practiced to clear fields for new crops. However, questions remain about the effects of fire on soil bacterial communities and soil properties in paddy fields. Here, five adjacent farmed fields were investigated in central Thailand to assess changes in soil bacterial communities and soil properties after burning. Samples of soil prior to burning, immediately after burning, and 1 year after burning were obtained from depths of 0 to 5 cm. The results showed that the pH, electrical conductivity, NH4-N, total nitrogen, and soil nutrients (available P, K, Ca, and Mg) significantly increased immediately after burning due to an increased ash content in the soil, whereas NO3-N decreased significantly. However, these values returned to the initial values. Chloroflexi were the dominant bacteria, followed by Actinobacteria and Proteobacteria. At 1 year after burning, Chloroflexi abundance decreased remarkably, whereas Actinobacteria, Proteobacteria, Verrucomicrobia, and Gemmatimonadetes abundances significantly increased. Bacillus, HSB OF53-F07, Conexibacter, and Acidothermus abundances increased immediately after burning, but were lower 1 year after burning. These bacteria may be highly resistant to heat, but grow slowly. Anaeromyxobacter and Candidatus Udaeobacter dominated 1 year after burning, most likely because of their rapid growth and the fact that they occupy areas with increased soil nutrient levels after fires. Amidase, cellulase, and chitinase levels increased with increased organic matter levels, whereas β-glucosidase, chitinase, and urease levels positively correlated with the soil total nitrogen level. Although clay and soil moisture strongly correlated with the soil bacterial community's composition, negative correlations were found for β-glucosidase, chitinase, and urease. In this study, rice straw and standing stubble were burnt under high soil moisture and within a very short time, suggesting that the fire was not severe enough to raise the soil temperature and change the soil microbial community immediately after burning. However, changes in soil properties due to ash significantly increased the diversity indices, which was noticeable 1 year after burning.

Cropping systems using forage grasses as cover crops have been effective in soil conservation and nutrient cycling, but root persistence of ruzigrass (Urochloa ruziziensis) is significant, and may impair root growth of the next crop. However, it is unknown how this would interfere with soybean root growth and yield under field conditions. Ruzigrass root persistence during soybean development, and its effects on soybean yield were studied under field conditions. Ruzigrass and soybean were grown alone or in rotation, and roots were sampled every 30 days and evaluated using carbon isotope discrimination. Despite temporary impairment of soybean root growth in the uppermost soil layer, there was no effect of ruzigrass on soybean yield. The ruzigrass root decay rate was high in the first 30 days after desiccation, and then it slowed down. Soybean roots grew slowly up to 30 days after planting (DAP, V7) and then peaked at 90 DAP (R5). Soybean root growth and yield are not affected by decaying ruzigrass roots. Around 50% of the ruzigrass roots are mineralized before soybean flowering. However, by soybean harvest there are still from 25 to 28% of non-decomposed ruzigrass roots up to the soil depth of 0.20 m.

We have reported by the statistical study that the correlation coefficients between the yield-constitutional factors of winter wheat and atmospheric and soil temperatures before and after severe winter were very high in highlands. Therefore we studied experimentally the influence of raising atmospheric and soil temperatures during December to April upon the growth and yields of wheat. The results were as follows: 1) Higher atmospheric temperature and higher soil temperature treatments in early March to late March increased the number of ripened grains per ear, probably as the results of the recovery effect resulted from the vigorous vegetative growth and also healthy differentiation induced by higher temperature. Higher temperature in early to mid-April increased the number of ears, probably as the results of effective spring tillering. By these reasons the yields were increased by the above two treatments. 2) Though higher temperature in December to February increased the number of stem in early spring period, it was decreased at the harvest time on account of the death of spikelets by subsequent cold weather. Consequently the yields were not increased by these treatment, although the growth of wheat was promoted

Spatial and temporal changes of soil properties and soil fertility evaluation in a large grain-production area of subtropical plain, China

Soybean (Glycine max) production is seriously threatened by ground-level ozone (O3) pollution. The goal of our study is to summarize the impacts of O3 on physiology, growth, yield, and quality of soybean, as well as root parameters. We performed meta-analysis on the collated 48 peer-reviewed papers published between 1980 and 2019 to quantitatively summarize the response of soybean to elevated O3 concentrations ([O3]). Relative to charcoal-filtered air (CF), elevated [O3] significantly accelerated chlorophyll degradation, enhanced foliar injury, and inhibited growth of soybean, evidenced by great reductions in leaf area (−20.8%), biomass of leaves (−13.8%), shoot (−22.8%), and root (−16.9%). Shoot of soybean was more sensitive to O3 than root in case of biomass. Chronic ozone exposure of about 75.5 ppb posed pronounced decrease in seed yield of soybean (−28.3%). In addition, root environment in pot contributes to higher reduction in shoot biomass and yield of soybean. Negative linear relationships were observed between yield loss and intensity of O3 treatment, AOT40. The larger loss in seed yield was significantly associated with higher reduction in shoot biomass and other yield component. This meta-analysis demonstrates the effects of elevated O3 on soybean were pronounced, suggesting that O3 pollution is still a soaring threat to the productivity of soybean in regions with high ozone levels.

This study develops a multivariate, nonnormal density function that can accurately and separately account for skewness, kurtosis, heteroskedasticity, and the correlation among the random variables of interest. The statistical attributes of the underlying random variables and correlation processes are examined. The potential applications of this modeling tool are discussed and exemplified by analyzing and simulating Corn Belt corn, soybean, and wheat yields. While corn and soybean yields are found to be skewed and kurtotic and exhibit different variances through time, wheat yields appear normal but also heteroskedastic. A strong correlation is detected between corn and soybean yields.