Improve Soil Chemical Properties Research Articles

Effect of reductive soil disinfestation on the chemical and microbial characteristics of rhizosphere soils associated with Salvia miltiorrhiza production in three cropping systems

Pre-planting reductive soil disinfestation (RSD) has been shown to restructure soil microbial communities and suppress soil-borne diseases. However, the effect of RSD on soil chemical and microbial characteristics in different cropping systems has not been studied. We sampled rhizosphere soils of Salvia miltiorrhiza, a staple medicinal plant in China, from three cropping system: continuous cropping monoculture, rotation cropping monoculture with Platycodon grandiflorus, and intercropped with Paeonia lactiflora. In a pot experiment, rice straw was applied as amendment to these soils before irrigating to saturation and covering with plastic film to simulate RSD. Soil chemical and microbial properties, mycorrhizal colonization, were determined using chemical analyses and high-throughput sequencing, and the growth of seedlings of S. miltiorrhiza was evaluated. RSD significantly improved soil chemical properties, changed the microbial community composition and structure, increased microbial diversity, and facilitated seedling growth. The efficacy of RSD differed greatly among the three cropping systems. RSD performed better in rotation soils compared to the soils from continuous cropping and intercropping. RSD markedly decreased the relative abundance of pathogenic Fusarium genus in intercropping soils only. In conclusion, the effectiveness of RSD should be evaluated in the context of a specific cropping system.

Bay leaf essential oils inhibited microbial growth and exerted potential preservation effects on tofu

Cattle manure contains high organic matter, so that this material is commonly used as plant nutrients in a form of organic fertilizer. In order to get a better understanding on the use of cow manure, the objectives of this research are (1) to determine the influence of liquid waste and solid livestock as fertilizer on soil quality and (2) to study the effect of both liquid and solid fertilizer on coffee plant growth. In this research, Completely Randomized Design (CRD) was employed as a research design, while data analysis was conducted using ANOVA. The F statistical test was applied to measure whether all independent variables could influence the dependent variable by using 5% and 1% (Alpha) degrees. The results showed that one time application of livestock wastewater improved C-organic chemical properties, N, P, CEC, Ca and Mg while soil chemical properties of pH, K, Na decreased. Two times application of livestock liquid fertilizer treatment improved soil chemical properties pH, N total, Ca, Mg and saturation bases. As for solid waste, one time treatment increased chemical properties of pH, C organic, N total, Ca and saturation of the base. The two times treatment could improve soil chemical properties of pH, N. total, P, Ca, Mg, base number and base saturation. Liquid waste fertilizer also found to provide significant effect on plant height and coffee plants quality. Additionally, (3) solid waste (compost) was found to have a significant effect on plant height, plant height rate and number of buds.

The effects of livestock’s waste utilization as fertilizer on coffee plant’s growth

Cattle manure contains high organic matter, so that this material is commonly used as plant nutrients in a form of organic fertilizer. In order to get a better understanding on the use of cow manure, the objectives of this research are (1) to determine the influence of liquid waste and solid livestock as fertilizer on soil quality and (2) to study the effect of both liquid and solid fertilizer on coffee plant growth. In this research, Completely Randomized Design (CRD) was employed as a research design, while data analysis was conducted using ANOVA. The F statistical test was applied to measure whether all independent variables could influence the dependent variable by using 5% and 1% (Alpha) degrees. The results showed that one time application of livestock wastewater improved C-organic chemical properties, N, P, CEC, Ca and Mg while soil chemical properties of pH, K, Na decreased. Two times application of livestock liquid fertilizer treatment improved soil chemical properties pH, N total, Ca, Mg and saturation bases. As for solid waste, one time treatment increased chemical properties of pH, C organic, N total, Ca and saturation of the base. The two times treatment could improve soil chemical properties of pH, N. total, P, Ca, Mg, base number and base saturation. Liquid waste fertilizer also found to provide significant effect on plant height and coffee plants quality. Additionally, (3) solid waste (compost) was found to have a significant effect on plant height, plant height rate and number of buds.

Characterization of Biochars From Tropical Biomass

Tropical country has a large biomass provide from agricultural residue. The biomass has potential to be processed as biochar. In general, biochar can be utilized as soil amendment in order to increase the ability of soil to retain nutrients, reduce surface runoff, due to excess water, and adding biodiversity of soils that are very useful for plant growth. The biochar characteristics are strongly related to the feedstock types and also their pyrolysis method. This research aims to study the physical characteristics of tropical biochar and their potential suitability in soil improvement. The biochar was produced by slow pyrolysis method using a vertical bed kiln. The feedstock were 9 types of agricultural residue including: mango leaf, longan leaf, teak leaf, mango branch, longan branch, rubber branch, corncob, rice straw, and rice husk. Temperature of the pyrolisis process was in the range of 400 °C to 600 °C. The results indicated that the physical properties of feedstock affects the characteristics of biochar. The higher bulk density and fixed carbon value the greater yield of biochar. Compare to their raw materials, the average water content of biochar was reduced (0.2–3.85 %), while pH increased (7.06–9.9). The electrical conductivity in general also increased (0.11–2.9 ds.m-1 ). Bulk density changed, corncob, and branches materials decreased, while rice straw, rice husk and leaves materials increased. The water holding capacity was a fairly low number (4–20 %). Application of the utilized biochar as a soil amendment is to improve soil chemical properties (pH, electrical conductivity, and availability of N-P contents) and physical properties (bulk density, porosity, and water holding capacity). Application for different soil types requires different biochar characteristics, it is influenced by the type of raw material used, temperature, and combustion time.

Rice Straw and Titonia Compost Granular Formation to Improve Onion Production in Regosol

Utilization of granule compost from rice straw (JP) and titonia (T) as a nutrient enrichmen for Regosol. Regosol has low nutrient content, especially in macro nutrient then it important to incease nutrient content for Onion cultivation. This research aims to study the effect of application granular compost from rice straw and titonia to the chemical properties and onion production. The research was conducted at the Wire House and Soil Chemistry Laboratory, Faculty of Agriculture, Andalas University. The design used was a completely randomized design (CRD) consisting of 4 treatments and 3 replications. The level of granul compost is 0 ton / ha; 7.5 tons / ha; 15 ton / ha; and 22.5 ton / ha. The results showed that giving JP and T granule compost improved soil chemical properties such as C-organic, N-total, P-available and K-dd soil. Aplication granular compost 22.5 tons / ha increased wet weight, dry weight, number and diameter bulb.

Effectiveness of compost and vermicompost from market organic waste to improve soil chemical properties

The purpose of this study is to evaluate the results of compost and vermicompost derived from market organic waste and its ability to improve soil chemical properties. Seven treatments consisted of treatments without organic matter (control), compost consisted of three treatments (2.5, 5, and 10 tons/ha), and vermicompost consisted of three treatments (2.5, 5, and 10 tons/ha). The treatments were arranged using a Completely Randomized Design with three replications. Each treatment was mixed with soil and incubated for eight weeks. After eight weeks the parameters observed consisted of total N, total P, available P, total K, Organic-C, and pH. The results showed a change in soil chemical content. The highest increase in soil chemical content was shown in the treatment of vermicompost. Application vermicompost 10 tons/ha had a significant influence on changes in soil pH, organic C, total P, available P, total K, and Compost 10 tons/ha increased total N. Vermicompost application of 10 tons/ha could increase total P (215.99%), available P (465.34%), total K (37.78%), pH (12.38%) and organic-C (40.34 %). Compost 10 tons/ha increases total N by (54%). Market organic waste effectively used as vermicompost and compost that could improve the soil’s chemical properties.

Higher NPK nutrients absorption due to the use of humic acid affects the growth and yield of baby corn applied with mungbean extract

This study aims to determine the growth and production of baby corn plants due to application of humic acid and mungbean sprouts extract. The study was conducted at the Teaching Farm of the Faculty of Agriculture, Hasanuddin University, Makassar from March to May 2018. This study used a factorial two-factor design that was arranged based on a randomized block design. The first factor was the application of humic acid consisted of control, 20, and 25 kg ha−1. While the second factor was the mungbean sprout extract concentration consisted of control, 5, 15, and 25 ppm. Each treatment was repeated 3 times, resulted in 36 experimental units. The results show that humic acid treatment can increase NPK uptake by corn plants and improve soil chemical properties. However, the two treatments had no significant effect on the growth and production of the baby corn plants. Application of 25 kg ha−1 humic acid and 25 ppm mungbean sprouts extract showed the best results on the parameters of the plant height (107.28 cm) and the highest number of leaves (15.56 leaves). Highest production per hectare was obtained both from the application of 20 kg ha−1 humic acid and 5 ppm of mungbean sprouts extract, and application of 25 kg ha−1 humic acid and with 15 ppm of mungbean sprout extract.

Application of geo-organo granule fertilizer derived from volcanic ash and tithonia on corn production at oxisols

Volcanic ash material (Vam) can cover the surface of the farming land post volcano eruption. The covering process could be advantageous for soil fertility if it is thin enough, but it can be destructive for the crops if it is thick. The purpose of this research was to study the effect of the application of Geo-organo granules from volcanic ash and Tithonia (Tt) for the production of Baby Corn in Oxisol. The pot experiments design with six treatments (1AV:1Tt; 1AV:2Tt; 1AV:3Tt; 1AV:4Tt; 1AV:0Tt; 0AV:1Tt)) three replications, and used Completely Randomized Design (CRD). The criteria test of compost standard used to test the benefit of these Geo-organo materials (PT Pusri, SNI, and Regulation from Agriculture Ministry, Republic of Indonesia). Corn growth was also measured for height and yield. Plant height and yield were analyzed using F-test and continued using HSD at a 5% level of significance. The results showed that Geo-organo granules be to improve soil chemical properties of Oxisol, and mass of cob of Baby corn.

Biochar Application Does Not Improve the Biochemical Properties of Ni Contaminated Soil

Waste disposal, metal plating, refineries, and mining operations frequently contaminate soils with nickel (Ni). We explored the effects of artificial Ni contamination (0, 56, and 180mg Ni kg-1) on the soil biochemical indices. The lab experiment also investigated the possible use of kunai grass (Imperata cylindrica) biochar at a 0.75% dry weight basis to alleviate contamination effects. The biochemical indices such as dehydrogenase enzyme activity, acid phosphatase enzyme activity, and soil respiration rates were monitored in three replications. High level of Ni (180mg kg-1) suppressed soil respiration rate by 37% and dehydrogenase activity by 62% up to 15 days. The acid phosphatase activity was not affected by Ni levels and was insensitive to Ni contamination. Biochar application to the Ni contaminated soil did not improve the soil's key biological properties. The beneficial effects of biochar could be limited to improvements in soil chemical properties and not on index biological properties.

Effects of straw decayed products of four crops on the amelioration of soil acidity and maize growth in two acidic Ultisols.

Variable charge soils have low agricultural productivity associated with low pH, low cation exchange capacity (CEC), and low pH buffering capacity (pHBC). As a result of rapid acidification rates, these soils are prone to infertility resulting from Al phytotoxicity and deficiency of P, Ca, Mg, and K, and thus require amendments that can ameliorate soil acidity and enhance soil CEC and pHBC. A 30-day pot experiment was carried out using a clay Ultisol and a sandy Ultisol amended with straw decayed products (SDPs) of peanut, pea, canola, and rice. The results showed that applying SDPs increased the soil CEC, organic matter content, and exchangeable base cations in the two Ultisols. The ameliorative effects of the SDPs were superior for the sandy Ultisol than for the clay Ultisol. The addition of SDPs significantly increased soil pH and pHBC of the two Ultisols, and simultaneously decreased soil exchangeable Al3+. Among them, the greatest effect was found in the treatment with pea straw decayed products (PeaSD). The soil pHs of clay Ultisol and sandy Ultisol treated with PeaSD were respectively 5.70 and 7.37 and were 1.26 and 2.63 pH units higher than those of control. Also, applying SDPs increased maize seedling biomass in both soils and the most significant effect was found in the treatment with PeaSD, which were 0.97 (clay Ultisol) and 2.5 (sandy Ultisol) times higher than in the respective controls. The results of this study demonstrated that carefully selected straws for SDP production can effectively improve soil chemical properties, enhanced soil pHBC, and thus promote agricultural sustainability.

Effects of Different Rates of Poultry Manure and Split Applications of Urea Fertilizer on Soil Chemical Properties, Growth, and Yield of Maize.

During integrated nutrient management involving poultry manure (PM) and urea fertilizer (UF) for maize (Zea mays L.), it is necessary to investigate the best time to apply UF that will optimize soil chemical properties, growth, and yield of maize. Hence, studies were carried out to investigate the effect of different rates of PM and single and split applications (SA) of UF on soil chemical properties, growth, and yield of maize. The treatment involved three levels of PM (0.0, 4.0, and 8.0 t·ha−1) and four sets of periods of UF: (i) 0 kg N ha−1 (control), (ii) 120 kg N ha−1 applied at planting (AP), (iii) two SA of 120 kg N ha−1 (90 kg N ha−1 applied AP + 30 kg N ha−1 at thirty days after planting (DAP)), and (iv) three SA of 120 kg N ha−1 (60 kg N ha−1 applied AP + 30 kg N ha−1 thirty DAP + 30 kg N ha−1 at tasseling). The 12 treatments were arranged in a randomized complete block design and replicated three times. PM and UF alone and integrating UF with PM improved soil chemical properties, growth, and yield of maize compared with the control. SA of UF three times (60 + 30 + 30) had the most improved soil chemical properties, growth, and yield of maize. Results also showed that maize yielded higher under UF integrated with PM compared with their sole forms. Application of 60 + 30+30 with 8 t ha−1PM (60 + 30+30 + 8 t ha−1PM) or with 4 t ha−1PM treatments showed the highest growth and yield of maize, but due to the bulkiness, handling challenges, and cost of PM, 60 + 30+30 + 4 t ha−1PM is recommended. Therefore, for better growth and yield of maize, after the initial application of PM, UF application should be split-applied in accordance with plant growth and the pattern of uptake to avoid losses by leaching and therefore ensured that N level in the soil is high at the critical stage of N demand.

Studies on the Effects of Liming Acidic Soils on Improving Soil Chemical Properties and Yield of Crops: A Review

Studies on the Effects of Liming Acidic Soils on Improving Soil Chemical Properties and Yield of Crops: A Review

Effectiveness of the combination of biopellet, biochar, chicken manure and fish waste to the improvement of chemical properties of sandy soil and soybean plant growth

Most of the activities of the use of organic fertilizers and natural additions of organic matter in agricultural intensification fields in Indonesia have not been able to compensate for the rate of decline in soil organic matter by the decomposition process. Biochar has a high C level and has the mean residence time in a long period in the soils. It has been proven that biochar applications may increase soil Carbon but have not been able to increase plant production. Therefore, the use of biochar combined with organic waste rich in nutrients is essential to develop. The purpose of this study was to determine the effectiveness of some biochar compositions with sugar cane, chicken manure, fish waste in the form of biopellet fertilizer on improving the chemical properties of sandy soils and the vegetative growth of soybean plants. This study used a completely randomized block design with two factors. The first factor (B) was the composition of biochar consisting of three levels, namely: 70% biochar, 15% chicken manure, 15% fish waste (B1), 50 % biochar, 25% chicken manure, 25% fish waste (B2), and 20% biochar, 40% chicken manure, 40% fish waste (B3). The second factor (D) was the dose of biopellet fertilizers consisting of four levels, namely: control (D0), 2.5 t/ha (D1), 5 t/ha (D2), and 10 t/ha (D3). The results showed that the addition of biopellet fertilizer effectively improved soil chemical properties (pH, C-organic, and CEC) and the availability of N, P, and K of the sandy soil. The effectiveness of increasing the soil total-N varied from 32.42 to 75.79%, P-available varied from 17.46 to 40.69%, and exchangeable K ranged from 8.7 to 25.67%. Improvement of soil chemical properties and the availability of N, P, and K by biopellet fertilizer application increased plant growth but reduced the weight of root nodules.

Effect of Application of Crotalaria juncea L. Compost on Availability and Uptake of Ca, Mg, S by Sweet Corn (Zea mays saccharata Sturt) on an Entisol of Wajak, Malang

Entisol is a type of soil at the initial development stage and has a texture dominated by sand fraction. This causes a decrease in soil quality and can reduce crop production. This compost of leguminase plants can play a role in improving soil chemical properties. The purpose of this research was to determine the effect of Crotalaria juncea L. compost application on the availability of secondary macro nutrients Ca, Mg, and S, and uptake of Ca, Mg, and S by sweet corn plant in Entisol, Wajak. Treatments tested were C0 (Urea 100%), C1 (Compost Crotalaria juncea L. 100% + Urea 75%), C2 (Compost Crotalaria juncea L. 100% + Urea 75%), C3 (Compost Crotalaria juncea L. 100%), C4 (Compost Crotalaria juncea L. 200%). The five treatments were arranged in a completely randomized design with three replications. The results showed that the application of Crotalaria juncea L. compost (20 t ha -1 ) significantly increased the availability of Ca, Mg and S on 12 weeks by 41.6%, 96.71% and 133.78%, respectively. The application of Crotalaria juncea L. compost (20 t ha -1 ) did not significantly increase uptake of Ca, Mg and S.

Application of Cow Manure and Trichoderma sp. on Ex-mining Land to Improve Soil Chemical Properties and Fragrant Lemongrass (Cymbopogon nardus L.) Growth

Ex-mining land has low productivity due to poor soil quality. One way to improve the quality of the soil is by providing organic materials, soil microbes, and plants that are known to be adaptive, such as fragrant lemongrass. The study aimed to determine the effect of the use of manure and Trichoderma sp. in improving soil chemical properties on ex-mining land. This research was conducted in Nagari Pala Luar, Koto Tujuh District, Sijunjung, and the Soil Laboratory, Agriculture Faculty, Universitas Andalas. The design used was Randomized Block Design (RBD) with 5 treatments (A = control / without cow manure and Trichoderma, B = 144 g cow manure + 14.4 gr Trichoderma sp. / planting hole, C = 288 g cow manure + 28, 8 gr Trichoderma sp. / planting hole, D = 432 g cow manure + 43.2 gr Trichoderma sp. / planting hole, E = 576 g cow manure + 57.6 g Trichoderma sp. / planting hole) and 3 replications. The results showed the use of cow manure and Trichoderma sp. able to increase nutrient content and of fragrant lemongrass growth in ex-mining land by giving 432 g cow manure + 43.2 gr Trichoderma sp. / planting hole.

Phosphorus availability as affected by the application of organic amendments in Ultisols

<p><span>The</span><span> adequacy and availability of phosphorous (P) in the soil during the </span><span>organic matter decomposition are important for plant growth, especially in the early stages </span><span>since most organic matter slowly release plant nutrients.</span><span> Therefore, this study was conducted to determine the availability of P during organic amendment</span><span lang="IN">s</span><span> in Ultisols</span><span>. The incubation experiment </span><span>used a completely</span><span> Randomized Design</span><span> (CRD) </span><span>for</span><span> 7 treatments</span><span> which consisted of </span><span>vermicompost, chicken, and cattle manure at the rate of 15 and 30 Mg ha<sup>-1</sup>. Soil and organic amendment</span><span lang="IN">s</span><span> were incorporated in</span><span>to a</span><span> 5 kg polybag and the mixture was incubated for 7 weeks. The soil was sampled at </span><span>the</span><span> 2, 3, 4, 5, 6, and </span><span>7 weeks, </span><span>and analyzed for </span><span>P availability and pH</span><span>.</span><span> Also, the </span><span>Total Soil Organic Carbon (TSOC), Total Soil Nitrogen (TSN), exchangeable Al, and Cation Exchange Capacity (CEC) were analyzed from </span><span>the </span><span>soil sampled either at week 4 </span><span>or </span><span>7. </span><span>The result showed that P increased slowly in the first 3 weeks of incubation, followed by a drastic continuous increase in week 4. </span><span>The experiment also confirmed that chicken manure released</span><span> the highest</span><span> and fastest </span><span>amount of P to the soil as compared to vermicompost, and cattle manure. On average, the increment of P was 2.28, 1.71, and 1.97 mg kg<sup>-1</sup> week<sup>-1</sup> for chicken manure, vermicompost, and cattle manure respectively</span><span>. Furthermore, the improvement of soil chemical properties was achieved using amendment as indicated by the increase in TSN, soil pH, and </span><span>a </span><span>decrease in exchangeable Al. The result </span><span>was </span><span>significant for P organic fertilization to </span><span>en</span><span>sure its availability for plant growth, leading t</span><span>o improved productivity, especially in organic farming systems</span><span>.</span></p>

Adding manure and zeolite to improve soil chemical properties and increase soybean yield

Increasing domestic soybean production is an important part of the effort to reduce reliance on imports. One potential area for improvement is developing soybean crops in Alfisols. Alfisols require intensive effort due to their poor soil chemical properties. Manure and zeolite were proposed as candidate materials that could be used to improve soil chemical properties to support plant growth and increase the productivity of cultivated land. The experiment was designed to study the addition of manure and zeolite on soil chemical properties of Alfisols and soybean yield. The experimental design was arranged in a factorial completely randomized block design with two factors—three rates of zeolite (Z0 = 0 t ha<sup>-1</sup>, Z1 = 2.5 t ha<sup>-1</sup> and Z2 = 5 t ha<sup>-1</sup>) and three manure variables (P0 = no manure, P1 = 5 t ha<sup>-1</sup> cow manure, and P2 = 5 t ha<sup>-1</sup> quail manure)—with three replications. The results showed that a combination of 5 t ha<sup>-1</sup> zeolite and cow manure increased soybean yield. However, zeolite 5 t ha<sup>-1</sup> resulted in the greatest improvement in soil chemical properties—the highest CEC, soil organic matter percentage, and pH.

Effects of Split Application of Urea Fertilizer on Soil Chemical Properties, Maize Performance and Profitability in Southwest Nigeria

Background: Since N fertilizer applied to maize (Zea mays L.) is prone to loss by leaching, it is important to derive an application time during the phenology of maize when the fertilizer is most efficiently and effectively used by the crop with minimal losses. Objective: Hence, experiments were carried out in 2014 at two locations in Osogbo southwest Nigeria to determine the effects of split application of N fertilizer on soil chemical properties, maize performance, and profitability. Methods: The treatments were: (i) control, (ii) 120 kg N ha-1 Applied at Planting (AP), (iii) two split applications (SA) of 120 kg N ha-1 {90 kg N ha-1 applied AP + 30kg N ha-1 at thirty Days After Planting (DAP) [90 + 30]}, and (iv) three SA of 120 kg N ha-1 {60 kg N ha-1 applied AP + 30 kg N ha-1 thirty DAP + 30 kg N ha-1 at tasselling[60+30+30]}. The four treatments were arranged in a Randomized Complete Block Design with three replicates. Results: Results indicate that at both sites, SA three times (60+30+30) has the most improved soil chemical properties, growth and yield of maize relative to other methods. The yield parameters increased in the order: control < 120 kg N ha-1 applied once < 90+30 < 60+30+30. Using the mean of both sites, 60+30+30 increased yield of maize by 15.3%, 37.1% and 138.2%, respectively compared with 90+30, 120 kg N ha-1 applied once and the control. Optimum returns were recorded by 60+30+30 with net return of ₦ 227,600 and a benefit cost ratio of 3.67:1 while the application of 120 kg N ha-1 applied once has a return of ₦ 157,200 with a benefit ratio of 2.9. These results show that farmers would benefit by making more profit by adopting the method of SA of N fertilizer three times (60+30+30). Conclusion: Therefore, for improved soil chemical properties, growth, yield and profitability of maize, N fertilizer application should be structured in accordance with this pattern of uptake to avoid losses by leaching and therefore ensure that N level in the soil is high at the critical stage of N demand.

The evaluation of basal respiration and some chemical properties of soils under cover crop treatments in a cherry orchard

Effects of different cover crops (CCs), mechanical cultivation and herbicide treatments on some soil chemical properties [pH, EC, total N, available P, exchangeable cations (Ca, Mg, K, Na) and the DTPA-extractable micronutrients (Fe, Mn, Zn, Cu)] and basal soil respiration (BSR) were investigated in a cherry orchard from 2013 to 2014. The present study was conducted in a cherry orchard located at the Experiment Station of Black Sea Agricultural Research Institute in Samsun province on the Northern side of Turkey. CC treatments, included Trifolium repens L. (TR), Festuca rubra subsp. Rubra (FRR), Festuca arundinacea (FA), T. repens (40%)+F. rubra rubra (30%)+F. arundinacea (30%) mixture (TFF), Vicia villosa (VV) and Trifolium meneghinianum (TM). Control treatments included mechanical cultivated (weed-free), herbicide treated (weed-free) and control plots, i.e., bare ground plots (with no cover crop) were allowed to become weedy. The experiment was conducted in a randomized complete block design with four replicates. The CCs were mowed in the flowering stages of the plants. After 90 days following seed harvest, soil samples were collected from two depths (0-20 and 20-40 cm) in each plot. All cropping species showed positive effects on soil chemical properties and BSR. The CC treatments decreased soil pH and exchangeable Na and increased EC, total N, available P, exchangeable cations (Ca, Mg, K) and the DTPA-extractable micronutrients (Fe, Mn, Zn). Effects of mechanical cultivation and herbicide treatments on soil chemical properties and BSR values were not found significant for both soil depths as compared to control (p<0.01). Results of the study showed that CCs, especially TR and VV treatments as legume plants improved soil chemical properties and BSR values in short term period. However, longer term studies are needed to evaluate the long-term effects of these sustainable management practices which have the potential to improve soil quality variables are encouraged.

Effects of green manure legumes and their termination time on yield of maize and soil chemical properties

ABSTRACT A two-year field experiment was conducted to examine the effects of interseeded green manure (GM) legumes in maize (Zea mays L.) cropping systems and their termination time on yield of maize and soil chemical properties in southern Ethiopia. Maize variety, BH540 was planted as the main crop while three GM legumes cowpea (Vigna unguiculata L. Walp), lablab (Lablab purpureus (L.) Sweet) and hairy vetch (Vicia villosa Roth) were interseeded between maize rows. The GM legumes were terminated and incorporated into soils at 30, 45 and 60 days after planting. The amounts of dry biomass produced varied significantly (p < 0.05) among GM legumes and their termination time. The results indicated that GM legumes accumulated over 39.3–65.5 kg N ha−1 yr−1 during 2014 cropping season and 53.3–156.6 kg N ha−1 yr−1 during 2016 cropping season. However, maize stover and grain N yields were not significantly influenced by GM. The results suggest GM legumes, lablab and cowpea improved soil chemical properties (N, P and K). Therefore, interseeding and incorporation of GM legumes can be considered as an alternative mechanism of soil fertility management for sustainable crop production in southern Ethiopia, where rotational and successional GM legumes cultivation is practically impossible.