High Soil Acidity Research Articles

The Effects of Soil Acidity and Aluminium on the Root Systems and Shoot Growth of Lotus pedunculatus and Lupinus polyphyllus.

Lotus pedunculatus (lotus) and Lupinus polyphyllus (Russell lupin) persist in the upland grasslands of New Zealand, where soil acidity and associated aluminium (Al) toxicity impede conventional pasture legumes. This experiment investigated the response of lotus and Russell lupin to soil acidity and Al. The species were sown in 20 cm tall 1.2 L pots of acidic upland soil. A mass of 4.5 or 6.7 g lime (CaCO3)/L was added to either the top or bottom or both soil horizons (0-9 cm and 9-18 cm), resulting in six treatments across six randomised blocks in a glasshouse. The soil pH was 4.4, 4.9, and 5.4; the exchangeable Al concentrations were 24, 2.5, and 1.5 mg/kg for 0, 4.5, and 6.7 g lime/L. At 16 weeks post-sowing, the plants were divided into shoots and roots at 0-9 cm and 9-18 cm. Root morphology, shoot and root dry matter (DM), shoot nitrogen (N), and nodulation were measured. The total plant DM and shoot-to-root DM ratio were higher, and the shoot %N was lower for the lotus plants than the Russell lupin plants for the various lime rates (13.2 vs. 2.9 g plant-1, 5.6 vs. 1.6, and 2.4 vs. 3.3%, p < 0.05). No response to lime in terms of total DM or total root morphology parameters was exhibited in either species (p > 0.05). Root morphology adjustments in response to acidity between soil horizons were not observed. The results indicated that lotus and Russell lupin are tolerant to high soil acidity (pH 4.4-5.4) and exchangeable Al (1.5-24 mg kg-1), highlighting their considerable adaptation to grasslands with acidic soils.

Kemasaman Tanah dan Sebaran Senyawa Pirit pada Berbagai Kedalaman Tanah Pasang Surut

Soil acidity (pH) is the main obstacle in tidal swampland. The high soil acidity (pH &lt; 4.0) causes an increase in the solubility of iron (Fe). The high soil acidity affects the balance of chemical reactions in the soil and the availability of nutrients in the soil. The purpose of this study was to determine soil acidity (pH), redox potential (Eh), and soluble Fe at at varying soil depths with different pyrite locations in tidal swampland. This study used a nested design and studied the following factors: 1) Depth of pyrite 0-50 cm layer (actual acid sulfate soil) and 50-100 cm layer (potential acid sulfate soil). 2) Soil depth includes 0-25 cm, 25-50 cm, 50-75 cm, and 75-100 cm. Soil samples were taken at the depth where pyrite was detected, with 3 replicates at each soil depth. This resulted in a total of 24 experimental units. The depth of the nested soil coincided with the depth of the pyrite. The study analyzed the acidity of acid sulphate soil, redox potential, and dissolved Fe at pyrite locations within soil depths of 0-100 cm and 0-25 cm, 25-50 cm, 50-75 cm, and 75-100 cm. The results indicate that there was no significant difference in the measurements between the various soil depths of 0-50 cm and 50-100 cm.

Ability of Nutrient Management and Molecular Physiology Advancements to Overcome Abiotic Stress: A Study on Sub-Saharan African Crops

Abiotic stress is a major cause of the declining crop yield worldwide, especially in tropical agricultural areas. Meeting the global food demand has become a serious challenge, especially in tropical areas, because of soil acidity, Al and Fe toxicity, drought and heat stress, and climate change. In this article, we reviewed several research and review papers from Google Scholar to list the different solutions available for the mitigation of abiotic stress, especially in tropical regions where several major crops, such as maize, sorghum, wheat, rice, soybean, and millet, are affected by abiotic stress and fertilizer input. In particular, Sub-Saharan Africa (SSA) has been affected by the low use of fertilizers owing to their high cost. Therefore, soil and plant researchers and farmers have developed many techniques to mitigate the effects of stress and improve the crop yield based on the agroecological zone and crop type. Nutrient management using chemical fertilizers alone or in combination with organic crops is a strategy recommended to cope with abiotic stress and increase the crop yield, particularly in developing countries. Notably, integrated soil fertility management has been effective in semi-arid areas under drought and heat stress and in subhumid and humid areas with high soil acidity and Fe toxicity in Africa. Recent advances in the molecular physiology of various crops considered a staple food in SSA have facilitated the breeding of transgenic tolerant plants with high yield. However, the feasibility and implementation of this technique in the African continent and most tropical developing countries are major issues that can be solved via adequate subsidies and support to farmers. This review can aid in the development of novel strategies to decrease hunger and food insecurity in SSA.

Genetic improvement of legume roots for adaption to acid soils

Acid soils occupy approximately 50% of potentially arable lands. Improving crop productivity in acid soils, therefore, will be crucial for ensuring food security and agricultural sustainability. High soil acidity often coexists with phosphorus (P) deficiency and aluminum (Al) toxicity, a combination that severely impedes crop growth and yield across wide areas. As roots explore soil for the nutrients and water required for plant growth and development, they also sense and respond to below-ground stresses. Within the terrestrial context of widespread P deficiency and Al toxicity pressures, plants, particularly roots, have evolved a variety of mechanisms for adapting to these stresses. As legumes, soybean (Glycine max) plants may acquire nitrogen (N) through symbiotic nitrogen fixation (SNF), an adaptation that can be useful for mitigating excessive N fertilizer use, either directly as leguminous crop participants in rotation and intercropping systems, or secondarily as green manure cover crops. In this review, we investigate legumes, especially soybean, for recent advances in our understanding of root-based mechanisms linked with root architecture modification, exudation and symbiosis, together with associated genetic and molecular strategies in adaptation to individual and/or interacting P and Al conditions in acid soils. We propose that breeding legume cultivars with superior nutrient efficiency and/or Al tolerance traits through genetic selection might become a potentially powerful strategy for producing crop varieties capable of maintaining or improving yields in more stressful soil conditions subjected to increasingly challenging environmental conditions.

Effect of Different Poultry Manure on the Performance of Tomatoes (Lycopersicon esculentum mill)

Purpose: Tomato is one of the most popular and versatile vegetables in the world and organic production with high yields of desirable quality are a target of many producers. However, the yield of tomatoes in Uganda are low compared to other parts of the world. The reason is that most soils in Uganda are low in fertility. There is widespread soil degradation, due to massive soil erosion resulting into loss of organic matter, high soil acidity and nutrient imbalance hence low crop yields. This study aimed at establishing the effect of different poultry manure on the performance of tomatoes.&#x0D; Methodology: The field trials were conducted in the mid altitude environment at BSU farm. Four treatments which included broiler, Layer, combination of Broiler and Layer chicken manure and the control were applied. The study was carried out in a randomized complete block design replicated four times. Measurements were made on number of leaves, number of flowers, plant height, fruit weight, fruit size, number of tomatoes and yield per hectare. Broiler and layer chicken manure increased the number of leaves, plant height number of flowers, number of fruits, fruit weight and fruit size significantly.&#x0D; Findings: The results indicate that poultry manure is very rich in macro nutrients. Among the treatments, broiler and layer chicken manure gave the highest fruit yield of 13.8 and 13.4 tons per hectare (t/ha) respectively. A combination of the manure produced 12.8 t/ha and the control treatment gave the lowest yield of 8.1 tons per hectare (t/ha). There was no significant difference between broiler and layer chicken manure. Both manures were equally good and enhanced yield. Therefore, farmers may opt for either of the two depending on the availability.&#x0D; Recommendation: The study recommend that either broiler or layer chicken manure can be used for production of tomato in order to achieve high yields.

Nutrient Dynamics in Acid Sulfate Soil Treated with Dolomite and Micronutrient Fertilizers and Their Effects on the Growth of Lowland Rice

The development of acid sulfate soils for agriculture is limited by high soil acidity, high soluble Fe, and low available P, base cation, and micronutrient contents. Therefore, the application of dolomite and micronutrient fertilizer is required to improve soil and rice productivity. This study aimed to determine the effect of dolomite and Cu and Zn fertilizer on the dynamics of nutrient availability in acid sulfate soils and their effect on the growth, nutrient uptake, and yield of rice. The study was conducted in a greenhouse and arranged in a completely randomized design with 13 treatments and 5 replications. The application of various doses of micronutrient fertilizer containing Cu and Zn oxide was compared with the control and dolomite application treatments. NPK as a basal fertilizer was applied according to the recommended dose for all treatments. The results showed that the application of micronutrient fertilizer and 3 tons ha-1 dolomite effectively increased the availability of P nutrient from 13.5 to 58.3 pp and decreased the potential for iron toxicity. Furthermore, applying 6 tons ha-1 dolomite, combined with 2 tons ha-1 organic fertilizer, and 6 ml l-1 micronutrient fertilizer resulted in the highest grain yield of 91.65 g pot-1 with an increase of 19%. Meanwhile, the application of 3 tons ha-1 dolomite and a combination of 3 tons ha-1 dolomite + 2 tons ha-1 organic matter could reduce 20-30% of iron uptake by plant roots. Application of dolomite and micronutrient fertilizers increases the productivity of soil and rice on acid sulfate soils.

VARIATIONS OF GETEROSIS SIZE OF GREEN MASS AND SEED YIELD IN HYBRID POPULATIONS OF LUCERNE SOWING IN CONDITIONS OF HIGH ACID ACID

The article highlights the results of studying the magnitude of heterosis and the nature of inheritance of forage and seed productivity in 37 hybrid populations (F3 and F5) of alfalfa sowing under conditions of high soil acidity (pH 5.2-5.3). It was found that among the hybrid populations of alfalfa F3 (2013-2016) in terms of forage productivity above the standard variety Sinyukha by 0.06-0.23 kg / m² (+ 5-20%) were: Mega / Regina, Vika / Regina, Zhidrune / Regina, Zhidrune / Sinyukha, Mega / Grilys, Yaroslavna / Vika, Yaroslavna / Zhidrune, Zhidrune / Vika, Grilys / Zhidrune, Vika / Mega and 15 more samples and parental forms of Zhidrune, Vika indicator. In the standard variety Sinyukha, the dry matter collection was 1.0-1.25 kg / m². The average interpopulation level was in the range of 0.98-1.25 kg / m2 depending on the year of use. Subsequent studies (2017-2019) among hybrid F5 populations only in Grilys / Mega, Grilys / Vika, Yaroslavna / Vika, Yaroslavna / Zhidrune and Grilys / Zhidrune revealed an increase in feed productivity to the standard by 5-11% or at 0.06-0.13 kg / m2 and 21 other samples and the parental forms of Grilys, Vika were on a par with him in this respect. In the standard variety of cyanosis, the dry matter collection was 1.09-1.41 kg / m². The average interpopulation level (MPC) was in the range of 1.03-1.31 kg / m². Heterosis (positive dominance) was detected in Mega / Regina (F3 hp = 69.37 and in F5 - 4.44) according to the degree of dominance of hybrid populations isolated by forage productivity in both F3 and F5; Vika / Regina (3.66 and 1.08); Gidrune / Regina (4.67 and 24.2); Yaroslavna / Vika (2.7 and 1.71); Yaroslavna / Zhidrune (2.56 and 5.11); Grilys / Gidrune (17,58 and 2.0). It should be noted that the heterosis index in these combinations ranged from 9.6 to 23.6% in F3, while in F5 it decreased to 0.5-19%. In terms of seed productivity in the period 2013-2016, only the combination Sinyukha / Mega was 20% higher than the standard among hybrid F3 populations and 8 more were on a par with it (Regina / Zhidrune, Sinyukha / Yaroslavna), Grilys / Mega, Grilys / Regina, Mega / Yaroslavna, Vika, Mega / Zhidrune). In the standard variety Sinyukha, the seed yield was 26.1-49.8 g / m2. The average interpopulation level was in the range of 16.7-52.5 g / m². During the following studies (2018-2020) among F5 hybrids no significant excess to the standard variety was detected, only the Regina / Mega population was on a par with it. Seed yield at the average interpopulation level was 9.3-22.9 g / m², in the standard - 25.0-37.5 g / m². Based on the results of this work, hybrid alfalfa populations with a combination of fodder and seed productivity against the background of high soil acidity were selected and proposed for use in the selection process: Regina / Zhidrune, Sinyukha / Mega, Sinyukha / Yaroslavna, Grilys / Mega, Grilys / Regina. They can be used separately in the selection process after further research: on forage productivity - samples Mega / Regina, Vika / Regina, Zhidrune / Regina, Zhidrune / Sinyukha, Mega / Grilys, Grilys / Vika Yaroslavna / Vika, Yaroslavna / Zhidrune, Grilys / Zhidrune , Vika / Mega; by seed productivity - Regina / Mega.

Rhizobacteria Mitigate the Negative Effect of Aluminum on Pea Growth by Immobilizing the Toxicant and Modulating Root Exudation.

High soil acidity is one of the main unfavorable soil factors that inhibit the growth and mineral nutrition of plants. This is largely due to the toxicity of aluminum (Al), the mobility of which increases significantly in acidic soils. Symbiotic microorganisms have a wide range of beneficial properties for plants, protecting them against abiotic stress factors. This report describes the mechanisms of positive effects of plant growth-promoting rhizobacteria Pseudomonas fluorescens SPB2137 on four pea (Pisum sativum L.) genotypes grown in hydroponics and treated with 80 µM AlCl3. In batch culture, the bacteria produced auxins, possessed 1-aminocyclopropane-1-carboxylate (ACC) deaminase activity, alkalized the medium and immobilized Al, forming biofilm-like structures and insoluble phosphates. Inoculation with Ps. fluorescens SPB2137 increased root and/or shoot biomass of Al-treated plants. The bacteria alkalized the nutrient solution and transferred Al from the solution to the residue, which contained phosphorus that was exuded by roots. As a result, the Al concentration in roots decreased, while the amount of precipitated Al correlated negatively with its concentration in the solution, positively with the solution pH and negatively with Al concentration in roots and shoots. Treatment with Al induced root exudation of organic acids, amino acids and sugars. The bacteria modulated root exudation via utilization and/or stimulation processes. The effects of Al and bacteria on plants varied depending on pea genotype, but all the effects had a positive direction and the variability was mostly quantitative. Thus, Ps. fluorescens SPB2137 improved the Al tolerance of pea due to immobilization and exclusion of toxicants from the root zone.

Manifestation of heterosis of signs of productivity in hybrids (F3 and F5) of lucern of seeding under conditions of high soil acidity

Aim. Assessment of the level of productivity, heterosis and the nature of inheritance in hybrids (F3 and F5) of alfalfa under conditions of high soil acidity (pH 5.2-5.3). Methods. Field, laboratory. Results. The results of research (2013-2020) on the level of productivity and effects of heterosis, the nature of inheritance of traits of fodder and seed productivity in 37 hybrid populations (F3 and F5), created with samples of alfalfa sowing and variable of different ecological and geographical origin, naturally soil background with high acidity (pH 5.2-5.3). Conclusions. Hybrid pop-ulations of alfalfa with a combination of high fodder and seed productivity against the background of soil acidity have been selected and proposed for use in the selection process: Regina / Zhidrune, Sinyukha / Mega, Sinyukha / Yaroslav-na, Grilys / Mega, Grilys / Regina. Samples Mega / Regina, Vika / Regina, Zhidrune / Regina, Zhidrune / Sinyukha, Mega / Grilys, Grilys / Vika Yaroslavna / Vika, Yaroslavna / Zhidrune, Grilys / Zhidrune, Vika can be used separately in selection process after further researches on forage productivity and seed – Regina / Mega.

Epistemic Uncertainties in the Assessment of Regional Soil Acidification

The increasing acidification of soil due to pollution and agricultural management practices is a growing problem worldwide, where food production is already under threat by climate change, more frequent droughts, and soil nutrient depletion. Soil acidification is quantified by pH measurements and is a primary metric for soil health. High soil acidity is a constraint on the production of grains and other crops because it decreases the bioavailability of important plant nutrients while increasing soil toxicity arising from an imbalance of essential soil elements. Field pH can be estimated by colour test kits which are very cost-effective and particularly suitable for developing countries where laboratory services are not available or fail to provide timely results. Because the pH test kit is based on visual colour matching between a colour card scale and a soil sample in solution, there are epistemic uncertainties, such as variability in expert opinion, differences in colour vision, measurement error, instrumentation, and changes in daylight spectral content. In this study, expert human observers were compared in experiments conducted using a standard pH test kit under a range of environmental conditions. A significant difference in uncertainty in colour discrimination was evident between male and female experts, whereas changes in daylight conditions had lower impact on the variance of pH estimates. In a group of subject matter experts, the male standard error (0.35 pH) was 57% higher on average over the range of pH values (pH = 4 → 10) compared to females (0.22 pH). This error was largest (70%) in the low pH 4 to 6.5 range, which is a critical range for successful amelioration of soil acidification. The results suggest that historical database measurements may have hitherto unrecognised uncertainties that affect confidence intervals for experimental data that in turn will have an impact on predictive models and policy development.

Efektivitas Fungi Mikoriza Arbuskula pada Tanaman Singkong (Manihot esculenta) di Tanah Inceptisol Bogor

Cassava is widely grown in Inceptisol. As agricultural land, the soil has several problems, i.e., high soil acidity, easily leached soil surface layers, unstable soil aggregates, and slow permeability. Arbuscular mycorrhizal fungi (AMF) form a symbiotic relationship with over 80% of higher plant species. However, the effectiveness of AMF on cassava has not been widely reported. This study aimed to determine the effect of AMF inoculants on the vegetative growth of cassava in Inceptisol. The AMF inoculants used were Gigaspora sp., Glomus manihotis, and a consortium of Acaulospora tuberculata and Glomus rubiforme. The experiment was performed in a Randomized Block Design with 8 treatments and 3 replications, i.e., M1 = G. manihotis; M2 = Gigaspora sp.; M3 = consortium of A. tuberculata-G. rubiforme; M4 consortium of G. manihotis-Gigaspora sp.; M5 consortium of G. manihotis-A. tuberculata-G. rubiforme; M6 consortium of A. tuberculata-G. rubiforme-Gigaspora sp.; and M7 consortium of G. manihotis-A. tuberculata-G. rubiforme-Gigaspora sp.; and control (as recommended dose of NPK fertilizers). In the AMF application treatment, 75% of the recommended NPK fertilizer was applied, thus saving 25% from the control. A total of 50 AMF spores were applied to each cassava plant and maintained for 8 weeks. The data were analyzed using the RStudio 4.1.1 program. The results showed that all treatments with AMF gave various effectiveness and could compete with the indigenous AMF. AMF application significantly increased the vegetative growth of cassava grown in Inceptisols, i.e., shoot and root dry weight, root length, P-uptake, and percentage of root infection. Application of G. manihotis and the consortium of A. tuberculata-G. rubiforme-Gigaspora sp. effectively increased cassava plants' growth for 8 weeks in Inceptisol. The AMF application could save 25% on the use of NPK fertilizers.&#x0D; &#x0D; Keywords: Acaulospora, cassava, Gigaspora, Glomus, fertilizer, mycorrhizal

KERAGAAN DUA BELAS VARIETAS UNGGUL BARU PADI PADA AGROEKOSISTEM LAHAN PASANG SURUT DI KALIMANTAN BARAT

The population of West Kalimantan continue to grow from year to year, led to increasing need for major food crops, especially rice. Farmers of West Kalimantan cultivate rice in various land agro-ecosystems, one of which is tidal swamp. Problems faced by farmers in rice cultivation on tidal swam include waterlogging, high soil acidity, poor nutrients, saltwater intrusion, and Fe toxicity. One of the efforts that can be done to increase rice productivity on tidal swamp is the introduction of new high-yielding varieties&nbsp; of rice with high yield potential. The purpose of this trial was to determine the performance of twelve new superior varieties rice with high yield potential on tidal swamp in West Kalimantan. The trial used a Randomized Block Design (RBD). The treatments were twelve new high-yielding varieties, namely Inpara 10, Inpari 32, Inpari 39, Inpari 45, Inpari 47, Inpari 48, Digdaya, Padjadjaran, Cakrabuana, Gemah, Mantap, and Cisaat, with five replications. The variables observed were plant height, number of productive tillers, panicle length, number of filled grain per panicle, percentage of filled grain per panicle, and&nbsp; productivity. The data were analyzed by ANOVA and further tested with the Tukey's Honest Significant Difference test. The results showed that the new high-yielding varieties with good performance and suitable for development on tidal swamp in West Kalimantan is Padjadjaran with productivity of 5.6 t/ha.

Effect of Varieties and Spacing on Radiation Efficiency, Growth and Yield of Sweet Corn (Zea mays saccharata Sturt.) in The Lebak Swamp Land

Corn is an important food crop in Indonesia which has a function as a source of food, a source of feed and the main ingredient for industry. Corn production in Hulu Sungai Utara Regency has increased from 2018-2020. However, it has not been able to meet market demand for corn because it is constrained by several factors such as lowland swamp land which is used as a place of cultivation with all the problems, namely periodically inundated land, low soil fertility, high soil acidity, toxic substances, lack of micro nutrients, organic matter still raw and others. From the aspect of cultivation technology, the use of superior varieties and proper spacing is influenced by environmental factors, especially climatic factors. The objectives of the study were: 1) Analyzing the interaction of varieties and planting distance on radiation efficiency and growth component of sweet corn (Zea mays saccharata Sturt.) in the lebak swamp land. 2) Analyzing the best varieties and the best planting distance for radiation efficiency and growth component of sweet corn (Zea mays saccharata Sturt.) in the lebak swamp land. This research was conducted in the lebak swamp land of ​​the STIPER Amuntai Experimental Garden, Muara Tapus Village, Hulu Sungai Utara Regency, South Kalimantan Province. At an altitude of ± 2 meters above sea level with coordinates of -2o28' South Latitude and 115o13"' East Longitude from May 2021 to August 2021. This study used a factorial randomized block design (FRBD) method. The first factor is the sweet corn variety (V) consisting of four levels, namely exsotic variety (v1), jambore variety (v2), talenta variety (v3) and ganebo variety (v4). The second factor is sweet corn planting distance (J) consisting of three levels, namely 75 cm x 20 cm (j1), 75 cm x 25 cm (j2) and 75 cm x 30 cm (j3). The results showed that the interaction between varieties and spacing did not affect all observation variables. Varieties affect the observed variables of plant height, number of leaves, leaf area index, plant growth rate, relative growth rate and number of seeds per row. Plant spacing affects the observed variables of plant height, leaf area index and plant growth rate. The best variety is the talent variety (v3) and the best spacing is 75 cm x 20 cm (j1) and the value of radiation use efficiency is 1,5584 g.MJ-1.

Spatial and Temporal Nutrient Dynamics and Water Management of Huanglongbing-Affected Mature Citrus Trees on Florida Sandy Soils

Nutrients are vital for plant growth, development, and aid in disease control because nutrients affect host plant and pathogen interactions. Once a citrus tree is infected with the phloem-limited, Gram-negative bacteria, Candidatus Liberibacter asiaticus (CLas), huanglongbing (HLB; citrus greening), it would fall under threat of survival as the disease has no known control mechanism discovered thus far. The objective of this study was to determine if split soil applications of essential nutrients improve the availability and accumulation, reduce leaching of these nutrients beyond the root zone, and promote root growth and water dynamics of HLB-affected citrus trees in the soil–plant–atmosphere continuum. Split soil applications of three N rates (168, 224, and 280 kg ha−1 year−1) were the main blocks. Micronutrients were randomly applied to the sub-blocks assigned in a split-split plot design, applied in three splits annually. The micronutrients were applied to foliage and soil as follows: foliar only 1× (1×), foliar 1× and soil-applied 1× (2×), and foliar 1× and soil-applied 2× (3×)× (1× = 9 kg ha−1 year−1 of Mn and Zn to each foliar and soil along with 2.3 kg ha−1 year−1 of B). Significant soil NH4-N and NO3-N, Zn, and Mn were retained within the active soil root zone (0–30 cm). Higher soil acidity was detected when trees received the highest micronutrient rate in the upper soil layers (0–15 cm) as compared with the middle (15–30 cm) and the lowest (30–45 cm) soil layers. Fine root length density (FRLD) was significantly lower at the highest micronutrient rates, manifesting root growth negatively associated with high Mn and low soil pH. Invariably, the water dynamics: stem water potential (ψstem), stomata conductance (gs), and sap flow were also negatively affected when trees received foliar 1× and soil 2× (3×) treatment as compared with the other treatments. Split application of nutrients had a significant effect on FRLD growth, retaining soil-applied nutrients within the active root zone, and improved water use efficiency.

Potentials of peatlands for agriculture in Tanjung Jabung Barat Regency, Jambi Province

Peatlands are considerably vulnerable and fragile. Despite this, peatlands serve as a place to live and to exercise sustainable farming for some communities. This study aims to examine the potentials of peatland in Tanjung Jabung Barat Regency for agricultural activities. Peatland distribution map with scale of 1:50,000 and the unanimous map on forest functions (TGHK map) are the main sources for this study. Laboratory analysis over seven soil samples were used for the assessment of land suitability, before overlaid with TGHK map to determine potentials and availability of lands for agriculture activities. Results showed that only 20,285 ha were suitable for agricultural activities. About 18,433 ha peatlands were classified as marginally suitable (S3) for food crops or horticulture, while the same level of suitability for annual crops occupied around 20,142 ha. Main limiting factors in land suitability were root condition (rc) due to deep to very deep peat depth categories; and nutrient retention (nr) due to high soil acidity. Utilization of peatlands for agricultural activities needs to appropriately conserve pristine condition to allow sustainable environment in the long term while maintaining and economic benefits. This research suggests that local water management, liming, fertilizer and minimum tillage would improve the quality of peatlands.

PENGEMBANGAN LAHAN BASAH SUB-OPTIMAL : PERTUMBUHAN Moringa Oleifera (L) PADA TANAH SULFAT MASAM YANG DIBERI BAHAN AMELIORAN

Moringa is a plant that has a myriad of benefits, either to fulfill human nutrition or as an ingredient used for animal feed. Information to the public is still very minimal about the benefits of this Moringa plant, and it also requires a large area of land to cultivate it. Acid sulphate land is a land that is underutilized as agricultural crop cultivation because it has a serious limiting factor, but has the potential to cultivate Moringa plants, because Moringa plants are tolerant of high soil acidity. This high soil acidity can be overcome by the addition of ameliorant materials in the form of husk ash and empty oil palm fruit bunches (OPEFB). Besides being able to improve the physical and chemical properties of the soil, ameliorant is expected to improve soil fertility in acid sulfate soils. This research was carried out by taking soil in the Barito Kuala area, precisely in the Tabukan sub-district as a polybag scale planting medium, this study used a factorial completely randomized completely randomized design method. The results of soil sample analysis showed that the characteristics of acid sulfate soils were very low, and had very high levels of toxic elements such as Fe and Al. While the results of the analysis of OPEFB compost the chemical element values ranged from high to very high so it was very good for application to acid sulfate fields. The treatment of OPEFB compost and husk ash affected the growth of the number of Moringa plant shoots with the best treatment being 20 ton.ha-1 and husk ash 10 ton.ha-1.

The Effect of Pelletized Lime Kiln Dust Combined with Biomass Combustion Ash on Soil Properties and Plant Yield in a Three-Year Field Study

Extensive application of mineral fertilizers resulted in high soil acidity, which is one of the major problems for crop production and soil degradation. Industrial solid waste, such as lime kiln dust and wood ash, can be used as alternative liming materials to benefit sustainable agricultural development. In this work, pelletized lime kiln dust with and without wood ash was utilized as liming material and the results of the three-year field study were compared with conventional mineral-based liming materials. It was determined that pelletized lime kiln dust satisfies the requirements posed by the recent European Union regulations to qualify as liming materials. The application of 2000 kg/ha Ca equivalent pelletized lime kiln dust increased soil pHKCl by ~0.55 pH units. Moreover, pelletized lime kiln dust significantly increased spring wheat grain yields ranging from 33.6% to 40.4%, depending on the pellet size. The usage of these liming materials not only increased crop yield but also decreased heavy metal concentration in soil. Due to high alkalinity, carbonate content, easy handling, and the transportation of pelletized lime kiln dust with and without wood ash, the materials have the potential to be used in agriculture as liming materials to reduce soil acidification and increase crop productivity or be used as soil amendments.

ANALYSIS ON THE CHARACTERISTICS OF EX-MINING SOIL AFTER 5 YEARS AND 10 YEARS OF REVEGETATION

Open-pit mining has affected landscapes and ecosystem balances immensely. The effects are including altered soil surface, decreased soil productivity, soil compaction, erosion and sedimentation, declined biodiversity, as well as deteriorated hydrological, hydrogeological, and atmospheric function of the surrounding area. Reclamation is one of the environmental restoration efforts that could be taken to improve these conditions. Physical and chemical properties of soil are the indicators of soil damage level as well as the success indicator of the reclamation program. This study aims to analyze the changes in post-mining soil characteristics after 5 years and 10 years of revegetation. The sample was selected by the purposive sampling method based on the age of plants and the vegetation density. The physical properties of post-coal soil after 5 years of revegetation are characterized by high soil acidity, low in organic matter (OM)/soil organic carbon (SOC), very low total N (nitrogen), moderate P availability, extremely high K2O, and moderate CEC. Whilst, the post-coal mining soil after 10 years of revegetation is found to be acidic (low pH), with moderate SOC, low total N, low P, very high K2O, and moderate CEC. Heavy metal (Fe, Mn, Al) contents in ex-coal mining reclamation area after 5 years and 10 years revegetation found to be in the high category.&#x0D; &#x0D; Key words: post-mining land, revegetation, soil characteristics

Перспективный биологический метод повышения урожайности, ростовых и формообразовательных процессов бахчевых культур, возделываемых в Астраханской области

Melon crops growing has long been the pride of Russian agriculture, especially the Astrakhan region. The natural conditions of the Lower Volga region are very favorable for growing gourds. However, under conditions of drip irrigation, phytopathogens develop, which significantly reduce the yield of cultivated crops. One of the dangerous diseases of gourds is anthracnose (pathogen Colletotrichum laqenarium), which spreads rapidly under favorable conditions high humidity combined with high air temperature, high soil acidity, lack of potassium and phosphorus, often leading to a complete loss of crop. In this paper, we studied the effect of a biological plant protection agent based on Bacillus atrophaeus, cultivated on legume and cornmolasses bases, on growth and shaping processes, yield and disease development of gourds in arid conditions of the Astrakhan region using watermelon (Citrullus lanatus) as an example. When testing laboratory samples of the product, a positive effect on increasing the length of the central lash, the number of leaves, shoots and fruits, the mass of fruits, as well as reducing the number of diseased fruits was proved. In addition to the impact on growth and shaping indicators, the studied samples had an effect on reducing the development of watermelon anthracnose throughout the growing season and increasing the yield of cultivated gourds. At the same time, the B. atrophaeus preparation cultivated on a legume nutrient medium more effectively influenced the studied parameters: it reduced the incidence of anthracnose in plants, reduced the number of diseased fruits, increasing crop yield and fruit weight. In general, the data obtained testify in favor of the fact that the use of biological agents based on B. atrophaeus in the agricultural fields of the Astrakhan region when cultivating watermelon shows the effectiveness of the development and implementation of microbiological methods of plant protection in the arid climate of the region.

Conjoint analysis of consumer preferences for pineapple fruit in Labuhan Batu District, North Sumatra

This study aims to determine consumer characteristics and attributes, and level of pineapple fruit, which are consumers’ preferences in Labuhan Batu District, North Sumatra Province. The largest peatland is on the east coast, namely in the Labuhan Batu District area of 192 thousand ha. Some research results support that pineapple is tolerant of high soil acidity levels, adaptive to peat swampland that is tolerant of pH 3‒4. Based on this, pineapple is a potential plant in Labuhan Batu District, so sustainable pineapple cultivation is needed. By understanding the characteristics, attributes of pineapple level, from consumer preferences, it is hoped that marketing and determining sales strategies can be adjusted to market demand: methods, conjoint analysis. The characteristics of the consumers used are gender, age, education level, type of work, family income per month, number of family members, and purchase frequency for attributes, taste, size, taste, color, and texture. The results of the study, the characteristics of age 25‒44 are consumers who consume the most pineapples. The combination of pineapple fruit that consumers like, fruit with a sweet taste, large size, strong taste, soft and smooth texture, and yellowish-green color. This can be considered in determining the target market and marketing strategy for pineapple in Labuhan Batu District, North Sumatra Province.