Fertigation Technique Research Articles

Kualitas Fungi Mikoriza Arbuskula (FMA) yang Diproduksi dengan Teknik Fortifikasi dan Fertigasi Berbeda pada Pertumbuhan Indigofera zollingeriana

Arbuscular mycorrhizal fungi (AMF) is a fungus that has a symbiotic impact on the plant at the root system level. The research objective was to evaluate the growth of Indigofera zollingeriana produced from inoculation of AMF under different fortification and fertigation techniques at the field scale. A completely randomized design with six treatments and five replication were applied for the study. The treatments were: FD1000, FD2000, FD3000 (AMF fortified with 1000, 2000, and 3000 ppm of AB mix at flat fertigation), FB1000, FB2000, and FB3000 (AMF fortified with 1000, 2000, 3000 ppm of AB mix at graded fertigation). The result shows that the AMF colonization level at the root of was similar (P>0.05) to the upper value of colonization (80.00‒99.00%). The entire products of AMF have similar favorable symbiotic effects on the plant with major growth traits (plant high, stem diameter, number of branches and twigs). A fortification of 2000 ppm of AB mix under graded fertigation technique has produced AMF that significantly (P<0.05) increased the number of leaves with higher green color level (7.5GY 4/6) compared with other treatments. In conclusion, the AMF produced by different fortification and fertigation techniques at the field scale has a similar result on root colonization effectivity and growth performance of I. zollingeriana. In addition, the AMF produced by 2000 ppm of AB mix with graded fertigation technique effectively increased the number of leaves with higher green color intensity. 
 
 Keywords: AMF, arbuscular mycorrhizal fungi quality, fertigation, fortification, Indigofera zollingeriana

Fertirrigation in coffee: agronomic and sustainable aspects

The present work aims to relate the positive effects of irrigation and mineral nutrition on coffee productivity, considering that the various existing methods and techniques involve a wide variation of dosage and nutrient splitting, due to the interaction between soil, water, climate, plant and area where the crop is located. Thus, through the methodology of literature review, a survey of research and theoretical notes of issues related to the benefits of irrigation and mineral nutrition was carried out, culminating in the focus of the fertigation technique. The study took into account aspects related to the rational use of water, the prevention of soil desertification and the Sustainable Development Goals of the UN 2030 Agenda. The analysis of the works and authors consulted made it possible to bring to the academic-scientific scope approaches that highlighted the fundamental role of fertigation in coffee farming.

Evolution of Lippia multiflora Biomass by the Fertigation Technique on a Ferralsol in the South of Côte d’Ivoire

In order to domesticate Lippia multiflora for its perpetuation, study was carried out at the National Center of Floristics (CNF) of the University Félix Houphouët Boigny of Côte d’Ivoire. The objective of this work is to estimate the biomass of Lippia multiflora (Verbenaceae), called “savannah tea”, under the effect of urea diluted in water (fertigation) over time on a ferralsol in southern Côte d’Ivoire. The trial was set up in a completely randomized Fisher block design with three replications. Potted Lippia multiflora plants received two doses of urea T1 (0.5 g) and T2 (1 g) previously diluted 1 liter of water and a control treatment T0 without urea addition. The effects of these different doses on the growth parameters of Lippia multiflora were compared with each other using analysis of variance to assess the growth parameters of the plant. The observations were made on the average height of the plants in centimeters (cm), the average diameter of the stem, the average number of leaves and roots. From the results obtained, the contribution of urea influenced the growth of Lippia multiflora because different from those of the T0 control. It appears that the application of urea T1 (0.5 g) best promotes the growth of Lippia multiflora.

RZWQM2 Simulated Drip Fertigation Management to Improve Water and Nitrogen Use Efficiency of Maize in a Solar Greenhouse

The drip fertigation technique is a modern, efficient irrigation method to alleviate water scarcity and fertilizer surpluses in crop production, while the precise quantification of water and fertilizer inputs is difficult for drip fertigation systems. A field experiment of maize (Zea mays L.) in a solar greenhouse was conducted to meet different combinations of four irrigation rates (I125, I100, I75 and I50) and three nitrogen (N) fertilizer rates (N125, N100 and N75) under surface drip fertigation (SDF) systems. The Root Zone Water Quality Model (RZWQM2) was used to assess the response of soil volumetric water content (VWC), leaf area index (LAI), plant height and maize yield to different SDF managements. The model was calibrated by the I100N100 scenario and validated by the remaining five scenarios (i.e., I125N100, I75N100, I50N100, I100N125 and I100N75). The predictions of VWC, LAI and plant height were satisfactory, with relative root mean square errors (RRMSE) < 9.8%, the percent errors (PBIAS) within ±6%, indexes of agreement (IoA) > 0.85 and determination of coefficients (R2) > 0.71, and the relative errors (RE) of simulated yields were in the range of 1.5–7.2%. The simulation results showed that both irrigation and fertilization had multiple effects on water and N stresses. The calibrated model was subsequently used to explore the optimal SDF scenarios for maximizing yield, water use efficiency (WUE) or nitrogen use efficiency (NUE). Among the SDF managements of 21 irrigation rates × 31 N fertilizer rates, the optimal SDF scenarios were I120N130 for max yield (10516 kg/ha), I50N70 for max WUE (47.3 kg/(ha·mm)) and I125N75 for max NUE (30.2 kg/kg), respectively. The results demonstrated that the RZWQM2 was a promising tool for evaluating the effects of SDF management and achieving optimal water and N inputs.

Otomatisasi Sistem Fertigasi Tetes untuk Tanaman Berbasis Mikrokontroler

The process of manual fertilization and irrigation of plants has disadvantages such as it requires human labor and is inefficient in the use of fertilizers and water sources. Therefore, the purpose of this research is to design and develop an automatic fertigation system. The method used in this research is a drip fertigation technique where the fertigation liquid that has been stirred is placed in a tank with 100 cm height from ground. With the gravitational force, the fertigation liquid is distributed through pipes, hoses and emitters around the plant. While the control system and automation of fertigation distribution to plants is carried out based on a microcontroller that need the condition of soil moisture values around the plant. If the watering time and humidity values are met, the electronic valve will open so that the fertigation liquid flows from the tank to the plants. Furthermore, in this study the tests were carried out to determine the uniformity coefficient and debit of drip fertigation. From the results, it shows that the emitter’s debit influenced by the liquid level in the tank. The uniformity coefficient obtained in the two tests is greater than 90%. From the two tests carried out from the moisture sensor 1 and 2, it shows the mean percentage error for both sensor is less than 1.7%, while the percentage error of soil moisture sensor 1 is 1.6% and the percentage error of soil moisture sensor 2 is 1%, respectively. Meanwhile, from the ultrasonic sensor testing it was obtained 0% of error. It also shows from the testing conducted that the fertigation system works very well and successfully.

Drip Irrigation Detection for Power Outage-Prone Areas with Internet-of-Things Smart Fertigation Managemant System

In drip irrigation agriculture or fertigation technique, sufficient amount of water and nutrients are crucial for a plant's growth and development. An electronic timer is usually used to control the plant watering automatically and the scheduling is set according to different levels of plant growth. The timer has to be adjusted frequently since the required amount of water is different according to the growth stages. In power outage-prone regions, the problem with scheduled irrigation using timer becomes worsen since the watering schedule is disrupted by occasional black-outs, leading to an insufficient supply of water and nutrients, which leads to poor crop yields. Typical solution for such problems is by hiring field works to monitor the functionality of the automated system, plant health, and to re-adjust the timer once a power outage occurs. However, this solution is ineffective, time-consuming, and acquires high overhead costs. This paper proposes a systematic irrigation method using the internet-of-things (IoT) framework in order to improve the monitoring of plant growth and consequently improves the efficiency of the workflow. This systematic fertigation monitoring system consists of power outage alerts, and on-line notifications of plant irrigation, pesticide delivery, and polybag cleaning schedule. As a result, by using the proposed system, higher efficiency in farming management is achieved, with a 40% reduction in manpower, as compared to a typical fertigation-based farming system. This system demonstrates greater control over irrigation scheduling, plant growth, recording of pesticide scheduling automatically, and polybag cleaning, all of which will improve crop yields significantly.

Characterisation of andrographolide in andrographis paniculata under different cultivation conditions

The trend in the practical uses of herbal medicine has gained increasing momentum in recent years. One of the trends includes the use of the andrographolide-containing Andrographis paniculata, which is a herb that is traditionally used as medicine. There are not many studies have investigated the cultivation of this plant. The aim of this study is to develop a standard of procedure for cultivating Andrographis paniculata using the fertigation technique. A total of 6 treatments in 2 growth medium compositions were studied; treatments T1, T3, and T5 in Cocopeat-RHA (70:30) and treatments T2, T4, and T6 in 100 % cocopeat. 3 magnesium compositions of 10 ppm (T1 and T2), 50 ppm (T3 and T4), and 70 ppm (T5 and T6) in nutrient solution were also studied. Treatments T1, T3, and T5 showed the potential for better growth quality with a maximum plant height of 32.51 cm, 32.51 cm, and 31.75 cm. The andrographolide content was comparable with controls 1 and 2 (0.67-0.70 µg/mL). In higher magnesium compositions of the nutrient solution, the dry herb yield of T5 and T6 decreased from 2.4 g to 1.6 g and 2.4 g to 1.2 g. The T3 and T5 treatments exhibited a higher yield than T4 and T6 based on a comparison of dry herb yield. The incorporated fertigation technique showed an on-par quantity of andrographolide yield to that of conventional techniques (0.67-0.70 µg/mL) although it showed an advantage of overcoming the cleanliness problem faced in this study. Hence, the T3 standard of procedure was deemed the best, as it gave better plant growth quality with a maximum plant height of 31.75 cm, a maximum number of leaves (141 total count), a good dry herb yield of 2.2 g, and better andrographolide content 0.7 µg/mL. The fertigation technique incorporated with the combined Cocopeat-RHA medium and 50 ppm magnesium composition in the nutrient solution is suggested for the cultivation of Andrographis paniculata.

Impact of Irrigation with Saline Water on the Production of Tomato (Solanum lycopersicum) under Soilless and Traditional Techniques

A greenhouse experiment was carried out to evaluate the response of tomato (Solanum lycopersicum) to saline water irrigation under soilless and traditional techniques. A special fertigation technique with two different salinity levels (1 dS m-1 and 4 dS m-1) of water was used under different soilless media, namely, perlite, gravel, and pozzolana as inert media, in addition to traditional techniques. Results showed that among the three soilless substrates, perlite medium produced the highest total yields with larger fruit sizes. Furthermore, the perlite medium enabled significant savings in water, compared to gravel (-15%) and pozzolana (-20%). Moreover, the results corroborated the existing knowledge on the tolerance of tomato to brackish water irrigation, since there was no significant difference in yield of plants grown in the soil irrigated with water with salinity levels of 1.1 dSm-1 and 4-5 dS m-1. Plant biometric data revealed a better and quicker development of plants grown in the soilless media compared to those grown in the soil, even in the case of freshwater irrigation.

Alfalfa canopy water interception under low-pressure sprinklers

Canopy water interception is an important factor in water use efficiency analysis and sprinkler-based fertigation technique development. In the present study, alfalfa canopy water interception and its influence factors were assessed under low wind conditions. The canopy interception capacity for three growth stages of alfalfa (S1, early vegetative stage; S2, late vegetative stage; S3, bud stage) were measured under two types of low-pressure spray sprinklers. The dynamics of canopy interception and interception ratio with irrigation depth were also observed. The total irrigation depth for all measurements was around 8 mm. A weight-based canopy interception measurement device was installed outdoors and integrated with a 20-psi sprinkler at 1 m above the canopy. The alfalfa canopy interception first increased rapidly with irrigation depth, but then stabilized and reached canopy interception capacity (Im). The minimum irrigation depths to achieve the Im values were 2 mm, 3 mm, and 4 mm at the S1, S2 and S3 stages, respectively. Im increased significantly across growth stages, and ranged from 0.46 mm to 1.49 mm. Interception ratio decreased gradually as irrigation depth increased. With an approximately 8-mm total irrigation depth, interception ratio ranged from 5.27 % to 17.59 % over all growth stages. Water application rate had no effect on Im, and Im decreased with droplet diameter. Generally, Im was higher and reached more quickly with the R3000 sprinkler compared to the D3000 sprinkler. Fresh weight, plant height, and LAI of alfalfa had significant positive correlations with canopy interception capacity, and a quadratic regression model was developed with using plant height as a factor. This study provides valuable and basic information for irrigation schedules and fertigation in alfalfa cultivation.

Effect of Fertigation Technique on Some Onion Physical Properties Using Different Emitter Types

Onion is the most widely-used flavoring vegetable in the world. And it is an important export crop in Egypt about 17%  529.631Tt., from total annually production. Scarcity of water resources in Egypt (arid and sigemi-arid regions) threatening food security. As well as, it is a limiting factor in agriculture expansion. So, maximizing irrigation water productivity by right combination of water and nutrients, and the method of fertilizer application through field water management practices (modern irrigation techniques, and fertigation) in irrigated crops, are a pre requisite for higher yields and good quality production. On the other hand it is very important to overcome water shortage and encourage environment preservation, particularly in sandy soils. Field experiment was conducted during 2016 /2017 season in private farm at Alexandria Cairo desert road, El-Behiara governorate. To study the effect of fertigation technique on some onion yield (quantity) i.e., bulb diameter “d1 and d2” (cm)., bulb mass “Bm” (g), bulb actual volume “Bv” (cm3), moisture content “MC” (%), and bulb yield “BY” (Mg fed-1)., through three emitters type, i.e., on line OT4 (I1), built in drip line GR 16 (I2) and built in drip line antiroots (I3), to obtain maximum irrigation water productivity, highest fertilizer effective, promoting yield quantity and quality and preservating environment of hyper mismanagement of water and fertilizer. Generally, results showed that using (I3) treatment recorded higher values compared with (I1) and (I2) treatments. Where, results indicated that, bulb yield “BY” (Mg fed-1) values increased about 8.32 and 2.77%., by using (I3), compared with (I1), and (I2). Also, using (I3) lead to increased irrigation water productivity “IWP” (kg m-3) about 66.1 and 33.2%., compared with using (I1), and (I2). In addition, it could be seen that bulb mass “Bm” (g), was increased by 60.77 and 14.39 %, when using (I3) compared with (I1) and (I2)

Effect of some selected soil properties, moisture content, yield and consumptive water use on two Cassava (TMS 0581 and TME 419) varieties

The increasing demand of Cassava for our dietary needs and shortage experienced going by the burgeoning global population is a cause for concern that require urgent attention. The study therefore considered the effect of some selected soil properties, nutrients, moisture content, yield and consumptive water use (CWU) on two selected Cassava varieties TMS 0581 and TME 419 respectively. The design was a Randomized Complete Block Design (RCBD) of four treatments and three replicates. Treatment A had fertigation, B used poultry manure, C employed NPK, 15-15-15 while D with no treatment was used as control. Soil properties such as Bulk Density (BD), Particle Density (PD), soil classification and nutrients such as Cation Exchange Capacity (CEC), Organic Matter (OM), Nitrogen (N), Potassium (K) and others were determined using standard procedures. Penman-Monteith (PM) model was used in estimating reference evapotranspiration (ETr) while its product with crop coefficient (Kc) produced crop evapotranspiration (ETc). Moisture content was measured at depths 10, 20 and 30 cm respectively while water use efficiency (WUE), irrigation water applied and tuber yield were also determined. The findings of this study showed that all the soil properties were within permissible levels to encourage optimum agronomic development of Cassava plant and the class was entirely a loamy soil which permits well-developed roottuber configuration. Tuber yields varied from 21.96 Kg to 25.13 Kg for TMS 0581 variety while TME 419 had 17.04 Kg to 31.63 Kg in all the treatments. Deficiencies were observed in some of the nutrients which were replenished with the introduction of the fertilizers among the plots. Moisture content at 30 cm depth is suggestive of adequate water availability sufficient enough to encourage proper tuber development for optimum yield while fertigation technique was adjudged the best as it improved Cassava Tuberization and WUE in all the treatments considered.

Evaluation of fertigation technique for phosphorus application of maize in the semi-arid region of Northeast China

To determine the best phosphorus (P) fertilizer management strategy in chernozem soil in the semi-arid region of Northeast China, a field experiment under film mulched drip irrigation was conducted for two consecutive years. Five P application methods were tested, including no P fertilizer applied (P0); P fertilizer one-time basal application (P1); one fertigation one time (P2); fertigation twice (P3) and fertigation four times (P4). The shoot dry matter weight, phosphorus accumulation, yield and POlsen in soil were measured regularly during the maize growing season. The results demonstrated that P fertilizer application methods imposed significant effects on dry shoot matter, the apparent P loss, P fertilizer use efficiency and yield of maize (P < 0.05). The yield, P agrinomic efficiency and P recovery efficiency of P4 treatment were significantly higher than P1 treatment by 4.2, 39.7, and 66.4% across two year. In addition, P4 treatment significantly enhanced the shoot dry matter weight after V12 stage, post-silking P uptake and reduced the apparent P loss. In conclusion, P fertigation and a rational frequency (e.g., fertigation four times) enable to keep the maximum grain yield, the shoot dry matter, and recovery efficiency of P fertilizer (66.4%) though changing agronomic methods for efficient acquisition of P toward a sustainable and productive agricultural fertigation system.

Diagnosis and management of soil fertility constraints in coconut (Cocos nucifera) : A review

Coconut (Cocos nucifera L.) is an important perennial plantation crop and to improve the productivity, the innate soil constraints should be ameliorated. The red, lateritic and sandy coconut soils are suffering with soil acidity, low CEC and poor nutrient reserve. A study on nutrient removal by coconut provides guidelines for the fertilizer input required. The effect of soil nutrient imbalance on the availability of nutrients emphasize the need based balanced fertilizer supply to coconut soils. The built up of soil available P in acidic red soils under continuous phosphatic fertilizer application strengthens the need to realize the soil test based fertilizer application. The potassium supply in the acid soils is poor, coconut being a huge feeder of potassium needs constant supply of potassium. Secondary and micronutrient deficiencies are emerging as potential yield limiting nutrients for coconut. Biomass recycling studies under coconut based cropping systems shows promising results in achieving the nutrient supply with the available biomass recycling through vermicompost. Minimizing the biomass exported out of farm especially coconut husk may improve potassium supply to palms through organic farming. Microbial studies showed that biomass recycling improved the beneficial microorganism in the rhizosphere and thereby enhances the nutrient availability. Fertigation technique showed higher nutrient use efficiency, soil and water conservation measures improved the yield of coconut in sandy soil and checks the losses through run-off and erosion in sloppy soils. Site specific soil management strategies can improve the coconut yield in an eco-friendly way.

DECAIMENTO DE BACTÉRIAS DO GRUPO COLIFORMES EM SOLOS COM COBERTURA VEGETAL E NU - DOI: 10.13083/1414-3984.v22n06a08

A fertirrigação é uma das alternativas para a disposição/tratamento de águas residuárias e traz, como grande vantagem, a possibilidade de aproveitamento agrícola dos nutrientes nelas contidos. Entretanto, é importante considerar o risco sanitário dessa prática, notadamente quando é utilizado esgoto doméstico submetido a tratamento inferior ao de nível terciário. Fatores como temperatura, incidência de raios UV, predação e competição podem proporcionar grande decaimento no número de micro-organismos exógenos no solo. Com a realização deste trabalho objetivou-se monitorar a sobrevivência e obter a taxa de decaimento de organismos indicadores, coliformes totais (CT) e coliformes termotolerantes (CF – E. coli), após 32 dias da aplicação de esgoto sanitário bruto em solo com cobertura vegetal e nu. A cobertura vegetal propiciou maior dispersão das bactérias no solo, proporcionando menor contagem na camada de 0-20 mm. Verificaram-se menores coeficientes de decaimento de bactérias do grupo coliformes totais que E. coli. No trigésimo segundo dia após a aplicação do esgoto sanitário, a contagem de E coli passou a ser insignificante tanto nas áreas em que havia cobertura vegetal como em solo nu, estimando-se que se tornem desprezíveis após 6,6 e 13,0 dias respectivamente, após sua aplicação ao solo. A fertirrigação mostrou ser uma técnica adequada para tratamento/disposição final de esgotos sanitários no que se refere à inativação de organismos patogênicos.

Effect of rooting time, pot size and fertigation technique on strawberry plant architecture

BACKGROUND: Flower induction and the reproductive and vegetative behavior of strawberry plants depend on several agronomic and nutritional factors. OBJECTIVE: During propagation in the nursery, several fertigation techniques (nutrient amount and timi

Increasing yield and agronomic efficiency of boro rice (Oryza sativa) by fertigation with bed planting compared with conventional planting.

The fertigation technique with raised bed planting for transplanted boro (winter, irrigated) rice production is a research focus nowadays. A field experiment compared two cultivation methods: the fertigation technique within raised bed planting on boro rice, and fertilizer broadcasting in the conventional planting method. Compared to conventional fertilizer broadcasting, results showed that the new fertigation technique in raised bed planting increased grain yield of transplanted boro rice by up to 17.04%. It yielded a greater number of panicles per square meter, a greater number of grains per panicle, higher 1000-grains weight, and better plant growth attributes. Sterility percentage and weed infestation were lower. Thirty six percent of irrigation water and time for application could be saved. Water use efficiency for grain and biomass production was higher. The agronomic efficiency of nitrogen (N) fertilizer was significantly higher. This study concluded that fertigation in raised bed planting for transplanted boro rice is a new approach with higher yield and higher fertilizer and water use efficiency than the existing agronomic practice in Bangladesh. Keywords: boro rice, fertigation with bed planting, de-nitrification, water use efficiency, harvest index, irrigated water management DOI: 10.3965/j.ijabe.20140705.004 Citation: Bhuyan M H M, Ferdousi M R, Iqbal M T. Increasing yield and agronomic efficiency of boro rice (Oryza sativa) by fertigation with bed planting compared with conventional planting. Int J Agric & Biol Eng, 2014; 7(5): 34－47.

Yeşil gübrelemede kullanılan bakla (Vicia faba L.) bitkisinin brokoli verimi üzerine etkilerinin belirlenmesi

The aim of this study was to determine the effects of using faba bean plant as green manure upon the subsequently grown plant. First in the experimentation, Rhizobium lupini bacterium was inoculated to faba bean plant in order to see the effect of inoculation. In the second stage of the experiment, bean plant was buried in the soil as green manure after its development and planting of Marathon F1 hybrid broccoli cultivar was performed after incubation. The experiment was planned with four replications according to the randomized block experimental design. Optimal fertilizers were administered with fertigation technique considering the soil characteristics. A statistical increase at 1% significant level was obtained at plant weight, plant length and number of nodules which were the analyzed characteristics of faba bean plant with bacterium inoculation. In the study, green manure application caused significant increases at curd weight, total yield, curd diameter, plant length and number of main leaves of the broccoli plant according to the green manure administration control conditions. Moreover, whereas the nitrogen and organic matter content levels of the soils taken after green manure administration increased, a decrease at pH levels of the soils was experienced. The research results showed that applications bacterium into the faba bean caused a positive effect upon the general characteristics of the faba bean and it also increased yield and other characteristics of the subsequent plant when it was used as green manure.

The effect of various light conditions and different nitrogen forms on nitrogen metabolism in pepper fruits

Abstract The ‘Spartacus’ F1 sweet pepper was grown in a plastic tunnel on rockwool during 2006-2008. A fertigation technique was used for water and fertiliser application. The tunnel was divided into two parts covered with different plastic films. The first part of the tunnel was covered with a film that transmitted less light than the film covering the second part. In both parts of the tunnel, the plants were divided into two groups. One group of plants was fertilised with just nitrate nitrogen (100% N-NO3) and the other one with three forms of nitrogen (N-NO3:N-NH4:N-NH2 in a ratio of 50:13:37). Fruits were harvested mature green and red. Concentrations of nitrate and ammonium ions as well as total nitrogen and free amino acids were analysed in the plant material. Nitrate and nitrite reductase activities were also investigated, and dry matter content and soluble sugars were also determined. Higher light intensity increased nitrate concentration in red pepper fruits but decreased ammonium ion content. These tendencies were not as obvious in green fruits. In most cases, red fruits fertilised with three nitrogen forms accumulated more nitrates than those fertilised with N-NO3. This observation was similar in the case of green fruits. In most cases, pepper fruits accumulated more ammonium ions in the case of N-NO3 fertilisation than when three forms of nitrogen were applied, but the differences were not always statistically significant. Higher nitrate reductase activity was observed in the case of better light conditions as well as mixed nitrogen fertilisation in red pepper fruits. No differences were observed in the case of nitrite reductase activity between fruits harvested from various treatments in red and also green fruits, with some exceptions. The green fruits of pepper had higher nitrate reductase activity than the red ones. It can be summarised that various light conditions influenced the nitrogen metabolism of pepper fruits as well as the different nitrogen forms applied with fertilisers.

Effect of Maturity Stage and Short-Term Storage on the Biological Quality of Sweet Pepper Fruits

Effect of Maturity Stage and Short-Term Storage on the Biological Quality of Sweet Pepper Fruits Sweet pepper plants of Spartacus cultivar were grown in plastic tunnel on rockwool using the fertigation technique. The three year experiment was carried out in 2006-2008. Fruits were harvested every year in three maturity stages: green, turning and red. The contents of ascorbic acid, phenols, soluble sugars, nitrate and ammonium ions, total nitrogen, free amino acids and dry matter were determined in freshly harvested fruits as well as after short-term (two weeks) storage. Red pepper fruits accumulated significantly more ascorbic acid, soluble sugars and phenols in comparison with the green and turning ones. The level of nitrate ions was highest in the green fruits and decreased during their ripening while the ammonium ion concentration increased. The lowest content of amino acids was observed in green fruits. Two week storage at 5-8°C, followed by two days at room temperature caused the reduction of nitrate ions in green and red fruits. Ammonium ion content as well as phenol and soluble sugar level increased in stored fruits, irrespectively of their maturity stage. Ascorbic acid content increased in the stored turning and red pepper fruits as related to its initial concentration. Dry matter content did not change after storage. Biological quality of harvested pepper fruits depended of their maturity stage, however, their response to short-term storage was similar.

Comparison Between Disc and Non-Woven Synthetic Fabric Filter Media to Prevent Emitter Clogging

The aim of this research was to compare the evolution of head loss in disc (130 m) and non-woven synthetic fabric filter media used to filter the water in drip irrigation systems. Two forms of treatment of the irrigation water were carried out: one with a chemical product (chlorine) and the other with none. The research used two different filter media: two for each treatment together with a fertigation technique with organic products in both types of treatment. The chemical treatment of the irrigation water was done by chlorination, in which the source of chlorine was sodium hypochlorite. Water from an open reservoir was used, in which a drip irrigation module was installed. The temporal variation in water quality over one year was analyzed, taking into consideration the physical, chemical, and biological parameters of water that can cause clogging problems in emitters. The results showed that, in irrigation water, the pH and iron chemical parameters presented an average risk of clogging, and the hydrogen sulfide parameters presented a high risk. The performance of the filters was analyzed by comparing the concentrations of the effluent on the disc and non-woven synthetic fabric filters in relation to the efffluent's physical and biological parameters. An attempt was made to follow head loss evolution in relation to the volume filtered by the filters so as to make a comparative analysis. It could be seen that the evolution of head loss was more significant and quicker with the non-woven synthetic fabric filter than with the disc filter. The level of clogging in the emitters was calculated by means of a uniform distribution index. The test area using the non-synthetic woven fiber filter presented the smallest level of clogging and the greatest water distribution index.