Kg Of Urea Research Articles

Biodiversity-safeguarding threshold for urea-fertilizer application on paddy fields: Protozoa-based toxicity tests

Urea is a widely applied fertilizer to enhance crop yields. Ecological risks associated with the excessive application of urea fertilizer threaten the paddy fields' sustainable agriculture and biodiversity preservation. There are no practical thresholds based on proven data on microbial communities. Protozoa are nitrogen-sensitive organisms. For the first time, this study conducted acute and chronic urea toxicity tests on eight species of organisms. The results indicate that Blepharisma sp. is the most sensitive species to urea exposure and is a suitable indicator for determining the safe threshold of urea. This study estimated the predicted no-effect concentration using species sensitivity distribution curves. Subsequently, it established the threshold for urea application in rice fields based on the fields' area and the surface water's height. The short-term safety threshold for urea in the studied paddy field with black soil is 87.7mg/L, equivalent to 43.85kg of urea per hectare for a single nitrogen fertilizer application. The long-term safety threshold is 5.02mg/L, representing the concentration for re-applicating urea. The biodiversity-safeguarding application threshold provides the basis for developing a urea fertilizer reduction protocol to safeguard the paddy fields' biodiversity.

ANTHROPOGENIC PRESSURE IN RURAL AREAS: DIAGNOSIS AND MAPPING OF POTENTIAL POLLUTION SOURCES AFFECTING WATER RESOURCESIN THE WATERSHED HEADS OF THE OUEME AND PENDJARI RIVERS IN THE COMMUNE OF COPARGO (NORTH-WEST BENIN)

Critical in assessing the quality and quantity of watercourses, headwaters of watersheds have been under anthropogenic pressure for several years, which has had negative impacts on water resources and soils. This study aims to assess the state of anthropogenic activities within the headwaters of the Copargo watersheds, followed by identifying and mapping potential sources of pollution to the water resources of the Oueme and Pendjari river headwaters in the Copargo municipality. To achieve this, data were collected through surveys, interviews, direct field observations, and remote sensing using Google Earth Engine. The results indicate that agriculture is the main activity, practiced by 90.84% of the population. Livestock farming (8.9%) and wood exploitation (7.2%) follow. The surveys reveal that the land is rarely left fallow, indicating overexploitation. The average duration of land cultivation during an agricultural season is 7.77 months. The agricultural inputs used include chemical fertilizers (NPK fertilizers and urea) and pesticides (herbicides and insecticides). On average, 120.5 kg of NPK fertilizer, 63 kg of urea, and 6.99 liters of pesticides are used per season per farmer. 2% of the producers attribute soil depletion to the use of agricultural inputs. The results of this study show that the potential sources of pollution in the study area remain anthropogenic activities, particularly agriculture, through the increased use of chemical fertilizers and pesticides (herbicides, insecticides). The absence of industrial units in the study area eliminates any risk of pollution from factories. Given the activities carried out in the area, this study will be followed by a physicochemical characterization of water resources and soils to evaluate their physicochemical and chemical quality.

Evaluation of Balanced Fertilizer Types and Validation of Soil Fertility Map-Based Fertilizer Recommendation for Bread Wheat Production in Bale Highland Southeastern Ethiopia

The optimal and appropriate fertilizer recommendation packages for all crops considering the improvement in productivity of small-scale farmers in the country. To evaluate the impact of blended fertilizer on wheat output, a field experiment using a five-treatment, three-replicate RCBD design was carried out during the 2020–2023 cropping season at Bale Highland southeastern Ethiopia to evaluate balanced fertilizer types and validation of soil fertility map-based fertilizer recommendation for Bread Wheat production The treatment 1Control (without fertilizer)2 (100 kg/ha-1 Urea )3 (100 kg /ha-1 NPS plus 100 kg of urea)4(100 kg /ha-1 NPSB plus 100 kg of urea) 5(100 kg /ha-1 NPSZnB plus 100 kg of urea). The plot size was 3m by 3 m (9 m2) and the spacing between plots and blocks was 1m and 1m, respectively in comparison to the control, The application of 100 kg ha-1 NPSZnB + 100 kg ha-1 urea in Bale Highland produced the highest and most significant yields of grains (5257.51 kg ha-1) the least amount of grain (3006.51 kg ha-1) in Bale Highland at the same time. To improve the production of wheat in the study area, farmers in Bale Highland must apply NPSZnB, with a similar agroecology.

A Systematic Review on Effects of Nitrogen Fertilizer Levels on Cabbage (Brassica oleracea var. capitata L.) Production in Ethiopia.

Cabbage (Brassica oleracea var. capitata L.) holds significant agricultural and nutritional importance in Ethiopia; yet, its production faces challenges, including suboptimal nitrogen fertilizer management. The aim of this review was to review the possible effect of nitrogen fertilizer levels on the production of cabbage in Ethiopia. Nitrogen fertilization significantly influences cabbage yield and quality. Moderate to high levels of nitrogen application enhance plant growth, leaf area, head weight, and yield. However, excessive nitrogen levels can lead to adverse effects such as delayed maturity, increased susceptibility to pests and diseases, and reduced postharvest quality. In Ethiopia, small-scale farmers use different nitrogen levels for cabbage cultivation. In Ethiopia, NPSB or NPSBZN fertilizers are widely employed for the growing of various crops such as cabbage. 242 kg of NPS and 79 kg of urea are the blanket recommendation for the current production of cabbage in Ethiopia. The existing rate is not conducive for farmers. Therefore, small-scale farmers ought to utilize an optimal and cost-effective nitrogen rate to boost the cabbage yield. Furthermore, the effectiveness of nitrogen fertilization is influenced by various factors including the soil type, climate, cabbage variety, and agronomic practices. Integrated nutrient management approaches, combining nitrogen fertilizers with organic amendments or other nutrients, have shown promise in optimizing cabbage production while minimizing environmental impacts. The government ought to heed suggestions concerning soil characteristics such as the soil type, fertility, and additional factors such as the soil pH level and soil moisture contents.

Utilization of Coffee Skin Waste as Compost Fertilizer in Tapak Gedung Village, Kepahiang

Tapak Gedung is a village where most residents work as coffee farmers. This means that this village has a lot of coffee skin waste. This coffee skin waste is just left to lie around without being processed into something useful. Therefore, Thematic KKN students developed compost fertilizer from coffee skin waste in Tapak Gedung village which aims to optimize the natural potential in the form of abundant but unutilized coffee skins. This product has utility value for village communities, especially farmers, the majority of whom live in the village. Using coffee skin waste as a basic material in the composting process is an efficient solution to reduce the amount of coffee skin waste in the village. The decomposition process is accelerated by the addition of EM4 bacteria, helping in the decomposition of manure thereby optimizing the composting process. Compost is made from 80 kg of coffee husk bran, 200 mL of EM4 diluted with 18 L of water, 20 kg of animal waste, and 1 kg of urea. Thematic KKN students conveyed information about composting coffee husk waste to the Tapak Gedung village community through outreach, discussions and PowerPoint slide presentations. As a result, the compost that has been produced is distributed to village communities and applied to crops and agricultural land.

The nutrient status of paddy fields is based on the results of the analysis of the Rice Soil Test Device (RSTD) in Jerukagung Village, Klirong District, Kebumen Regency.

This study aims to determine the nutrient status of the soil and obtain fertilization recommendations based on the results of the analysis of the Rice Soil Test Device (RSTD) in Jerukagung Village, Klirong District, Kebumen Regency. Data collection was carried out by data analysis with RSTD, direct interviews and distribution of questionnaires to farmers who own rice fields. Sample selection is carried out by random sample method (probability sampling). The number of samples taken by 30 farmers from 4 farmer groups who have paddy fields in Jerukagung Village, Klirong District, Kebumen Regency.Based on the test results using RSTD, with a low N content (86.67%) so it needs to be fertilized 250 kg of Urea / ha. The P content is high (86.67%) so it needs to be fertilized 50 kg SP-36/ha. The K content is medium (73.33%) so it needs to be fertilized 50 kg KCl / ha or by using straw as much as 5 tons / ha. The degree of acidity or pH in general is neutral (60%), which is in the range of pH 6-7 so that the recommendation for N fertilization is in the form of Urea with a conventional drainage system.

Effects of different fertilizer applications on yield, yield components and fiber quality in cotton (Gossypium hirsutum L.)

Bu çalışma, 2020-2021 yıllarında Şanlıurfa-Harran koşullarında tesadüf blokları deneme desenine göre Candia pamuk çeşidi kullanılmış olup ve 3 tekrarlamalı olarak yürütülmüştür. Her parsel 5 sıra olup, parsel uzunluğu 12 m, sıra arası 70 cm ve sıra üzeri mesafe ise 10-12 cm olarak uygulanmıştır. Deneme, toplam 24 parselden oluşmuştur. Çalışmada farklı kimyasal ve organik gübrelerin karışımlarından oluşan uygulamalar uygulanmıştır. Bunlar, 1-Kontrol, 2-Taban gübresi (0 kg)+Üst gübre (Üre 35 kg da-1), 3-Taban gübresi (10 kg DAP da-1 )+Üst gübre (Üre 35 kg da-1), 4-Taban gübresi (20 kg DAP da-1 )+Üst gübre (Üre 35 kg da-1), 5-Taban gübresi (30 kg DAP da-1 )+Üst gübre (Üre 35 kg da-1), 6-Taban gübresi (2 ton çiftlik gübre -1da)+ Üst gübre (Üre 35 kg da), 7-Taban gübresi (4 ton çiftlik gübre da-1)+Üst gübre (Üre 35 kg da-1), 8-Taban gübresi (6 ton çiftlik gübre da-1)+Üst gübre (Üre 35 kg da-1) karışımları uygulanmıştır. Hasat sonrası ölçümlerde dekara verim (kg da-1), koza sayısı (adet bitki-1), koza ağırlığı (g), koza kütlü ağırlığı (g), çırçır randımanı (%), 100 tohum ağırlığı (g), lif inceliği (mic.), lif kopma dayanıklılığı (g tex-1) ve lif uzunluğu (mm) incelenmiştir. Çalışmadan elde edilen sonuçlara göre; denemenin iki yılında da en fazla koza sayısı (24.33 ve 24.66 adet bitki-1); koza ağırlığı (6.66 ve 6.55 g); dekara verim (526.40 ve 514.66 kg da-1) 6 ton çiftlik gübresi + 35 kg üre uygulamasından elde edilmiştir. Çalışmaya konu olan uygulamaların lif kalite özelliklerine etkisinin olmadığı saptanmıştır.

Improvement of Soil Nutrient and Yield of Maize Through the Application of Different Rates of Sawdust - Piggery Compost Fortified With Urea

Fortification of compost with inorganic fertilizer is necessary to compliment for some deficient nutrient in organic manure to improve soil fertility and crop yield. This experiment was carried out at Ambrose Alli University Teaching and Research Farm, Ekpoma, Nigeria and it was fitted in a Randomized Complete Block Design (RCBD) with seven treatments replicated thrice. The treatments were; Control, 2 tonnes of saw dust piggery compost + 75Kg/ha of urea, 4 tonnes of sawdust piggery compost + 75kg of urea, 6 tonnes of sawdust piggery compost + 75kg of urea (75kg Urea +6 SPC), 8 and 10 tonnes of compost, 150kg/ha of urea. Data collected were analysed using ANOVA and LSD was used to separate means. It was observed from the initial soil test that the soil nutrients status was below critical levels and this necessitate the application of the fertilizer to improve the fertility status of the soil. The application of 75kg Urea + 6 SPC significantly (p≤0.05) increased the soil nutrient status compared to other treatments. The growth, cobs weight, dry matter and grain yield of maize were significantly (p≤0.05) higher with application of 75kg Urea +6 SPC compared to other treatments. Also, the nutrient uptake of maize was significantly (p≤0.05) higher with application of 75kg Urea + 6 SPC. In conclusion, the application of 75kg Urea +6 SPC significantly (p≤0.05) increased the soil nutrient status, growth and the yield of maize.

Application of manures reduces inorganic fertilizers requirement for maize grown in a sandy soil

The use of inorganic fertilizers with high doses is not recommended in the sustainable maize production program. The present study aimed to evaluate soil chemical properties and growth of maize plants treated with several types of manure to reduce the use of chemical fertilizers in sandy soil. An experiment was conducted in dryland with pumped deep-well water in Gumantar Village, North Lombok Regency, from May to July 2021. There were three types of manure tested: cow, poultry, and goat manures (20 ton/ha) treated with and without BeKa decomposer. All the manure treatments received 75% of chemical fertilizers applied in the control treatment (500 kg of urea and 380 kg/ha of NPK Phonska). The treatments were arranged in a randomized block design with three replicates. The results showed that the poultry manure treatments, with and without decomposer, increased soil pH significantly. This increase improved soil chemical properties, such as available P and K. Plant height, stem diameter, leaf area index at silking, and total N in leaf tissue, were not significantly different among the treatments. These results showed that the application of manures, with or without decomposer, could substitute 25% of the inorganic fertilizers needed by maize plants grown in sandy soil.

The effect of fertilizer treatments on morphological and qualitative traits of Flixweed And coriander (Descurainia sophia (L.) Schur) and (Coriandrum sativum L.) in the Agroforestry Systems.

Agroforestry is an old concept in which trees, crops and livestock have traditionally been grown on small farms.The ecological, economic and social benefits of agroforestry operations over integrated agriculture are well recognized, but the acceptance of these systems is slow. Non-use of fertilizers and their low profitability may be a reason for the acceptance of these systems by farmers. In this study, the use of biofertilizers, organic and chemical fertilizers to improve yield, quality traits and thus greater profitability of this system are considered. The tree species selected for the agroforestry system included cherries (Prunus avium L.) and walnuts (Juglans regia L.). Two species of coriander (Coriandrum sativum L.) and Flixweed (Descurainia sophia (L.) Schur) were cultivated understorey of the agroforestry system. Also, according to the Data collected from scientific resources, there are two types of biofertilizers, including Bioazospir Bacterial Fertilizer and Micomix Endomycorrhizal Fertilizer. Organic livestock (3 kg per square meter) + humic acid organic fertilizer (Agri Plus) (0.5 kg per 100 liters of water), b) Micromix endomycorrhizal biofertilizer (1000 g per square meter), c) Bioazospir biofertilizer (200 g) per thousand kg of seeds), d) Chemical fertilizer based on soil test (5 kg of urea and 155 kg of triple superphosphate and 1550 kg of potassium sulfate at the beginning of planting plus 1000 kg of potassium sulfate in 10 days after sowing And 1000 kg (from 2 months after Cultivation per hectare) and e) control Treatment (without fertilizer) was used.

Problems of primary processing of cotton and biotechnological method of their solution

T he aim of the research i s to solve the problems of preserving the natural properties of cotton fiber and seeds. After analyzing the reasons that deteriorate the quality of cotton fiber and seeds, a new non-waste technology for cleaning cotton is proposed, as well asadditional resources for making a profit, which are biofertilizer, bio-solution and alkali. Methods and results. In laboratory conditions, biofertilizers and a solution were obtained with properties close to those of biofertilizers and solutions with the addition of dust extracted during cotton cleaning. To do this, in 30 kg of land collected from the fields, which could be moved by a light wind, were added5 kg of sheep manure, 5 kg of cattle manure, 3 kg of chicken manure, 0.5 kg of nitrate, 0.5 kg of urea, 0.5 kg of phosphate fertilizers as catalysts, they were placed in a 100 liter container, filled with water and following the procedure the desired product was obtained. The use of biological solution and biofertilizer contributes to the restoration of the fertile structure of the soil, an increase in cotton yield by 25–30%, improvement of the natural properties of cotton fiber and seeds, ecology.

Grain yield response of maize (Zea mays L.) to variable rates of compost and nitrogen fertilizer integrations

Haimanot Beruk , Tewodros Ayalew & Tarekegn Yoseph.2021.Grain yield response of maize (Zea mays L.) to variable rates of compost and nitrogen fertilizer integrations.Journal of Innovative Agriculture.volume 8, issue 2, Pages 17-21. Declining soil fertility is one of the major factor limiting crop productivity in Ethiopia. This experiment was therefore, conducted to evaluate grain yield response of maize to variable rates of compost and urea fertilizer integration. The experiment was arranged in factorial combination of three level of compost (0, 5 and 10 t ha-1) and three levels of mineral N fertilizer in the form of urea (0, 92 and 105 Kg ha-1). The experiment was laid out in randomized complete block design with three replications at the experimental field of Hawassa University, Southern Ethiopia. The result revealed significant difference among compost levels for all of the traits studied. There is significant difference among nitrogen levels for grain yield, number of kernel per row, number of kernel per ear and hundred grins weight. Significant difference among treatments (combination of compost level and nitrogen level) were observed for grain yield, number of rows per ear, number of kernel per row, number of kernel per ear and hundred kernel weights. The combination of compost and urea at the rate of 10 t ha-1 and 105 kg ha-1, respectively, produced the highest kernel yield (11.3 t ha-1) followed by (10 t ha-1 and 92 kg ha-1) and (5 t ha-1 and 105 kg ha-1) with compost and urea combination 9.4 and 8.3 t ha-1 grain yield respectively. Generally, the combination of 10 t ha-1 compost with urea at the rate of 105 kg ha-1 resulted with 63% yield advantage compared with the control plot. It is therefore; wise to recommend 10 t ha-1 compost combinations with 105 kg of urea for improved maize yield for the farmers in the research area and areas with similar agro-ecology and resources availability.

Can organic soil ameliorant and foliar organic fertilizer improve maize yield and reduce inorganic fertilizers input in a dryland semiarid?

There is still room for improving maize yield and cultivation practices in dryland semiarid areas since the current production is still low and the inorganic fertilizers (IF) input is high. This study aimed to assess possible roles of a commercially available organic soil ameliorant (OSA) and foliar organic fertilizer (FOF) to improve maize yield and to reduce IF input in a dryland semiarid area. One experiment with seven treatments were tested, namely: (A) 100% of IF doses, that consisted of 500 kg of urea and 360 kg of NPK Phonska (15-15-15) per hectare, (B) Treatment A plus OSA and FOF, (C) 70% of IF doses plus OSA and FOF, (D) Treatment A plus OSA, (E) 70% of IF plus OSA, (F) Treatment A pus FOF, and (G) 70% of IF plus FOF. The size of each treatment plot was 10.1 m2 and there were 90 plants in each plot. All the treatments were replicated three times and were arranged in a randomized block design. The results showed that the IF treatment (A) produced 11.0 kg per plot, equal to 10.9 ton/ha. Adding OSA or FOF on top of IF (D and F), produced only 3% higher than the IF alone. However, when OSA and FOF were applied together with IF (B), the yield was 6% higher than the IF alone. The 30% reduction of inorganic fertilizer could not be replaced by both OSA and FOF (E and G) in producing yield. OSA improved soil nutrients, such as available phosphorous, potassium and C-organic but not the total nitrogen.

Growth stage wise fertigation scheduling improves nutrient uptake, growth and yield of capsicum under protected conditions

The studies were conducted to evaluate the effect of varying levels of fertilization according to physiological stages of capsicum under protected conditions during 2015–2017. The experiment was laid out with five fertilization treatments for five crop physiological stages of capsicum and replicated four times in Complete Randomized Block Design. The treatments were soil fertilization as control (T1), fertigation as per recommended dose (T2) and 80%, 100% and 120% fertigation of the recommended dose split into stage wise schedule (T3, T4 and T5, respectively). Treatments registered significant differences in respect of growth, yield and nutrient uptake of capsicum grown in polyhouse. Significantly higher plant height and Leaf Area Index (LAI) under T4 and T5 indicated higher vegetative growth under these treatments. Number of fruits per plant, fruit weight and yield of capsicum registered highest value under T5 which was at par with T4 but significantly higher than other tried treatments. Highest dry matter accumulation and nutrient uptake was also recorded under this treatment being at par with T4 but significantly higher than other treatments. Based on the study, it was concluded that for 1000 m2 polyhouse, 158 kg of water soluble fertilizer (19:19:19), 9.0 kg of urea and 47.5 kg of Murate of potash are required to meet the nutrient requirement of capsicum at vegetative (1 to 25-DAT (Days After Transplanting)), flowering (26 to 42-DAT), fruit set (43 to 57 DAT), fruit growth and development (58 to 84 DAT) and harvesting (85 to 231 DAT) stages. Therefore, results of the study established that single source and basal dose or equal split of fertilizer is not sufficient to meet the nutrient requirement of capsicum at different physiological stages and needs to be supplemented with additional nutrient sources.

Rhizobacterial inoculation in combination with mineral fertilizer improves maize growth and yield in poor ferruginous soil in central Benin.

The use of biotechnological approaches to increase soil fertility and productivity allows to obtain sustainable agriculture with lesser use of chemical fertilizers. The present study aimed to determine whether the inoculation of Bacillus panthothenicus, Bacillus thuringiensis, Pseudomonas putida, Pseudomonas syringae, or Serratia marcescens combined with reduced doses of NPK (nitrogen, phosphorus, potassium) fertilizer can improve the growth and yield of maize on poor ferruginous soils under field conditions in central Benin. For this purpose, maize seeds of the EVDT 97 STR C1 variety were inoculated with 10 ml suspension of five plant growth-promoting rhizobacteria (PGPR) strains, and the plots were fertilized at seeding with the recommended doses (0, 25, 50, 100%) of 200 kg/ha of NPK and 100 kg of urea for corn cultivation. The study was conducted in a completely randomized design with 3 replicates. The results showed that except for P. syringae , which induced the highest fresh aerial biomass (94.51%) and dry aerial biomass (63.63%), all other parameters were positively improved with inoculation associated with reduced doses of NPK + urea. The best height, leaf area, fresh underground biomass, and grain yield were recorded in response to the application of P. syringae + 50% NPK + urea, with an increase of 26.82, 32.23, 107.57, and 30.64%, respectively, compared to those of the control. The inoculation of seeds with P. syringae + 50% NPK + urea can be considered to be an environmentally sustainable strategy for maize cultivation.

Reactive nitrogen loss from livestock-based food and biofuel production systems considering climate change and dietary transition

Nitrogen (N) is an essential element for food production. Under the influences of correlated variables of food demand and socio-economic development, a hybrid approach was proposed to identify reactive nitrogen (Nr) loss from livestock-based food and biofuel production systems. The approach included the following components: (1) crop simulation model, DeNitrification-DeComposition, taking into account several field situations and climate change scenarios, and (2) correlation analysis of five types of livestock-based food demand and economic benefits based on copula functions and Markov Chain Monte Carlo simulation. The approach was applied to the Guangdong–Hong Kong–Macao Greater Bay Area (GBA) in China. Production of fodder crops (maize, wheat and soybeans) was examined under two climate change scenarios, Representative Concentration Pathways 4.5 and 8.5. Influence of international trade of soybeans, wheat, and maize on nitrogen fertilization was examined under two additional scenarios. Results showed that compost production from livestock manure and food loss in the production of 1000 kg of livestock-based food would reduce demand for 10.45 kg of urea in crop production, accounting for 9.2%–14.66% of total nitrogen fertilizer demand. Among all livestock-based food, fertilizer demand between 2020 and 2030 is projected to be the highest in fodder crop production to support pork production. Total Nr loss of livestock-based food production in GBA was estimated to be 1.10 to 1.58 Mt under scenario 1, and 1.09 to 1.57 Mt under scenario 2.

The feasibility of reducing yield gap by improving crop management

An appropriate solution to increase crop production is to improve production per unit area. Reconsiderations are, therefore, necessary in various agricultural systems and their production potential. To evaluate agronomic factors affecting crop yield and feasibility of reducing wheat yield gap, a questionnaire was developed in terms of yield-affecting management factors. For this purpose, data of most important factors affecting wheat yield were recorded from farmers sampled from different parts of Piranshahr, a southern city in West Azerbaijan province, Iran. The results showed that the management applied throughout the season had a significant effect on wheat yield. The lands with more than three hectares, flat, and northward with loam-clay soil texture yielded relatively higher crop. The yields were also higher in the lands plowed in March and August with a three-plough moldboard connected to a four-cylinder Ferguson tractor, flattened using a trowel, and rotated with fallow and pea. The use of phosphate (100-150 kg ha−1), potash, and micro fertilizers, as well as 100-150 kg of urea (50 kg in spring and 50 kg in autumn) led to increased yield. The use of Granstar (60 g) and 1.0 L of 2, 4-D separately, and 0.5 L of a pesticide resulted in a better seed yield. Harvesting of wheat in July 15-25 using Hyundai and 130k combines resulted in higher yields. The percentages of studied managements, including land characteristics, planting, growing, and harvesting in wheat fields were 13, 35, 27, and 25 percent, respectively.

Dynamics of pH, Ferrum and Mangan, and Phosphorus on Newly Opened Paddy Soil having High Soil Organic Matter on Rice Growth

Research had been carried out at the Research and Soil Testing Laboratory and Greenhouse of Soil Research Institute, Bogor using newly opened paddy soil from Pesisir Selatan districts, West Sumatra (one year old). Total treatments tested were 12 which were combination of farmer rate, NPK recommendation (½×; ¾×; 1½×), straw compost (½×; ¾×; 1½×), and dolomite. The trial was conducted using a completely randomized design with three replications. This research had been prepared in two units, one unit for observing plant response to nutrient management and another unit for incubation trial with the same treatment placed in the greenhouse. Rice cultivar used was IR-42 in accordance to the preferred varieties of local farmers. The sampling method for measuring the solubility of Fe2+ and Mn2+, as well as the availability of PO43- was by centrifuge 50 g mud samples from the incubation pots then separated clear extract using filter paper. The observation results on dynamics of pH, Fe2+, Mn2+ and PO4-3 mainly occured in 1 to 14 days after submerging (incubation). After 14 days soil reaction had reached thermodynamic sequence of oxidation-reduction processes, the PO43- more available and pH of the soil reached the peak. The optimum dose of NPK fertilizer obtained 0.875 NPK or equal to 175 kg of urea, 87.5 kg of SP-36 and 87.5 kg KCl ha-1. The highest number of hills achieved from straw compost treatment 1½ organic matter (OM) or 3 tons with an increase of 20%. Application of ameliorant dolomite increased the number of tillers about 2-3%, but insignificantly different with no dolomite treatment.

The Effect of Different Dosages of Nitrogen Fertilizer on Rice Growth and Leafroller Populations

Rice ( Oryza sativa L.) is an essential cereal grain crop, cultivated in tropical and subtropical areas, particularly in Asia . Several insect species are known to infest rice plants, both in open fields and in storage rooms. However, higher amounts of nitrogen fertilizer can increase plant growth, they may be responsible for initially attracting these insects to the plants. The field experiment for this study measured the effects of different nitrogen application rates on leafroller populations and rice crop growth. Five doses of nitrogen fertilizer were applied at three different times, with insect populations recorded after each application in leaf samples from six randomly selected spots on each plot. The results indicated that an optimum fertilizer dose of 75kg of urea per acre can minimize leafroller infestations and maximize plant growth. Moreover, this optimum application of fertilizer might also help plants develop resistance against invasive pest populations. DOI : 10.7176/JBAH/9-7-08 Publication date : April 30 th 2019

SALIBU technology in Indonesia: an alternative for efficient use of agricultural resources to achieve sustainable food security

SALIBU technology (rice ratooning modification) is an innovation in rice farming technology allowing ratoon crops to be harvested up to 3.5–4 times annually with a yield equivalent to that of the main crop. Although the practice of rice ratooning in Indonesia has a long history, SALIBU technology was invented as recently as 2010 by Mr. Erdiman, one of the co-authors of this paper. This technology is already well known by local farmers, who realize that with it, they need only sow and transplant once, and can then harvest repeatedly. Accordingly, it includes scope to reduce the time taken to cultivate paddies and the usage of water, seed and labor. The purpose of this paper is to introduce the SALIBU technology and to highlight its excellence in terms of its role in using agricultural resources efficiently. This paper also reviews several previous researches which become the basis of its innovations and development. One research was conducted by Erdiman et al. (2013) in several districts of West Sumatra Province related to treatments for: (1) stem-cutting height, (2) cutting timing and (3) dosage of NPK fertilizers. The research findings indicated that the optimum results in terms of productive tillers, number of grains per panicle and rice productivity came when the stem-cutting height was 3–5 cm above ground level and the stems were cut 7–8 days after harvesting and fertilizer dosage was 150 kg of urea and Ponska, respectively. Another experiment showed no significant difference in rice productivity among three agroecosystem zones namely highland, moderate and lowland for the application of SALIBU technology.