Plant Growth Medium Research Articles

Conservation of beneficial microbes between the rhizosphere and the cyanosphere.

Biocrusts are phototroph-driven communities inhabiting arid soil surfaces. Like plants, most photoautotrophs (largely cyanobacteria) in biocrusts are thought to exchange fixed carbon for essential nutrients like nitrogen with cyanosphere bacteria. Here, we aim to compare beneficial interactions in rhizosphere and cyanosphere environments, including finding growth-promoting strains for hosts from both environments. To examine this, we performed a retrospective analysis of 16S rRNA gene sequencing datasets, host-microbe co-culture experiments between biocrust communities/biocrust isolates and a model grass (Brachypodium distachyon) or a dominant biocrust cyanobacterium (Microcoleus vaginatus), and metabolomic analysis. All 18 microbial phyla in the cyanosphere were also present in the rhizosphere, with additional 17 phyla uniquely found in the rhizosphere. The biocrust microbes promoted the growth of the model grass, and three biocrust isolates (Bosea sp._L1B56, Pseudarthrobacter sp._L1D14 and Pseudarthrobacter picheli_L1D33) significantly promoted the growth of both hosts. Moreover, pantothenic acid was produced by Pseudarthrobacter sp._L1D14 when grown on B. distachyon exudates, and supplementation of plant growth medium with this metabolite increased B. distachyon biomass by over 60%. These findings suggest that cyanobacteria and other diverse photoautotrophic hosts can be a source for new plant growth-promoting microbes and metabolites.

Interactive effects of silicon and potassium on photosynthesis and physio-biochemical traits of rice (Oryza sativa L.) leaf mesophyll under ferrous iron toxicity

Iron toxicity originated from excess ferrous ion (Fe2+) availability within plant growth medium remains a potent stress severely limiting rice productivity via alteration of photosynthetic and metabolic processes. Silicon (Si) or potassium (K) individually can enhance plant tolerance to abiotic stresses, including metal toxicity. However, their combined mitigation effects lack proper exploration even though greater alleviation potential could possibly be achieved. The objective of the present study was to evaluate the potential of combined application of Si and K in mitigating Fe2+ toxicity impairments to rice leaf mesophyll tissue. The experiment was laid out in a factorial combination of two Fe2+ levels (0 and 300 mg L−1), two Si levels (0 and 56 mg L−1), and two K levels (0 and 200 mg L−1) following a completely randomized design. Excess Fe2+ impaired leaf mesophyll performance by negatively affecting all tested parameters; however, Si and K significantly reduced those impairments. The integrated application of Si and K resulted in the maximum mitigation effects as high as 23%, 27%, 14%, 40%, 25%, 37%, 24%, 48%, 34%, 28%, 41%, and 15% for total chlorophyll content, maximum quantum yield of photosystem II, membrane stability index, relative cell death, lipid peroxidation, total protein content, free proline content, total polyphenol content, hydrogen peroxide content, total antioxidant activity, net photosynthetic rate, and plant biomass, respectively, compared with the control, with 29% decrease in Fe content and 4.2-fold and 1.7-fold respective increase in Si and K content of rice leaf mesophyll. Silicon or K enhanced photosynthetic performance by boosting antioxidant activity, proline content, and polyphenol content, thereby reducing oxidative damages from Fe2+-generated free radicals like hydrogen peroxide; however, K was comparatively more effective than Si. The combined application of Si and K resulted in significantly better Fe2+ toxicity alleviation response over their sole application for the maximum studied traits. The findings would contribute to the present understanding of Fe2+ toxicity alleviation and help in strategizing crop management practices for sustainable rice production in Fe2+-toxic lowlands.

Pengaruh Pemberian Pupuk Kascing Dan Cangkang Telur Ayam Terhadap Pertumbuhan Dan Produksi Terong Bulat Pondoh (Solanum Melongena L.)

One of the reasons for the low eggplant production in Riau is that the soil type in Riau is generally Red Yellow Podzolik (PMK). Utilization of PMK soil as a medium for plant growth is faced with various problems, especially the physical, chemical and biological properties of the soil which are less supportive for growth. To be able to improve PMK soil, it is necessary to provide a lot of organic matter, such as vermicompost fertilizer. Vermicompost organic fertilizer is an organic fertilizer plus, because it contains macro and micro nutrients and growth hormones that are readily absorbed by plants. In addition, giving egg shells is a household waste that can still be used to fertilize plants. Eggshell contains 94% calcium carbonate, 1% calcium phosphate, 1% magnesium carbonate and 4% organic compounds (Rahmawati and Nisa, 2015). The high calcium carbonate contained in eggshells can be used as an alternative source of calcium. The purpose of this study was to determine the effect and the best combination of casting and chicken eggshell fertilizer on the growth and production of pondoh round eggplant (Solanum melongena L.). This research was carried out experimentally using a factorial Completely Randomized Design (CRD), which consisted of two factors, namely K (Kascing Fertilizer) consisting of 3 levels, and factor C (Chicken egg shells), consisting of 3 levels, each consisting of 3 repetitions, The number of experimental units is 27 plots, each plot consists of 4 plants and 2 plants as samples, so that the total plant is 27 x 4 = 108 plants. The result of this research is that the interaction of vermicompost fertilizer and chicken egg shells has a significant effect on plant height, stem diameter, number of fruits, fruit weight per plant, fruit diameter of eggplant plants, by giving 100 g of castor fertilizer/plant and 30 chicken egg shells. g/plant is the best dose in this study.

Pengaruh Media Tanam terhadap Pertumbuhuan Kacang Hijau (Vigna Radiata)

There are various types of planting media, but not all types of planting media are suitable for growing certain types of plants. The planting medium used must be adjusted to the type of plant to be planted. A good planting medium for plant growth must have good physical properties, be loose and have the ability to hold water. The planting medium is a place where plants grow and develop, so it needs special arrangements and treatment. Using soil growing media alone is not enough to support plant growth and yields, so it is necessary to add organic materials that can provide nutrients and provide loose soil texture and the ability to store water. Mung bean is an annual plant which is quite widely cultivated in Indonesia. Green beans themselves are included in tropical plants and their cultivation is quite easy. Green beans (vigna radiata) as a source of vegetable protein. Another advantage of mung bean plants is that they are early maturing or short, mung bean plants are also tolerant of drought because they are deeply rooted and can grow on soils that are poor in nutrients so they can be cultivated on marginal lands. Climatic conditions desired by green bean plants to be able to grow and produce well in lowland areas up to an altitude of 500 meters above sea level with optimal rainfall of 50 - 200 mm/month, temperature 25 - 27 ⁰C, humidity 50 - 80% and enough light sun.

Zeoponic formula for plant growth media for ornamental plants Aglaonema siam aurora and Anthurium crystallinum

Plant growth media (PGM) play a crucial role in producing healthy and valuable ornamental plants. A good PGM has the suitable physical, chemical, and biological properties that can help realize the total growth and development potential of the plants. One PGM developed that meets these requirements is a zeoponic, made from zeolite, compost, and cocopeat as raw materials, and formulated specifically for ornamental plants. Ornamental plants are horticultural commodities with high economic value driven by fast-growing demand. However, a common problem in the cultivation of ornamental plants is the unwanted degradation in the appearance of the leaves, e.g., turning into pale and faded color. Hence, the application of an accurate dosage of macro and micro fertilizers on zeoponic ornamental plants can boost growth and enhance the aesthetic value of the plants. With this in mind, this study aimed to find the precise fertilizer formula, specially or even exclusively, for ornamental plants. The experiment was arranged in a factorial completely randomized design (CRD) with two factors, namely (1) plant species consisting of Aglaonema siam aurora and Anthurium crystallinum, and (2) fertilizer dosage consisting of different combinations of N, P, and K fertilizers as well as micro fertilizers. Test parameters observed were plant height, number of leaves, leaf length, leaf width, leaf chlorophyll, and plant beauty. PGM analysis was carried out by measuring pH, EC, available-N, available-P, cation exchange capacity, exchangeable bases, organic-C, and micronutrients. This study showed that zeoponic with a dosage of 0.375 g/l NPK fertilizer was the best for Aglaonema siam aurora, while zeoponic with a dosage of 0.75 g/l of NPK fertilizer was the best for Anthurium crystallinum plants. The use of zeoponic media is highly recommended owing to its suitable chemical properties (e. g, neutral pH, favorable EC and CEC).

Composition of Macro and Micro Fertilizers in Zeoponics for Growing Variegated Ornamental Plants

A suitable plant growth medium (PGM) is essential in cultivating ornamental plants, which are raised mainly for their high aesthetic value. For instance, variegated plants are hugely popular among ornamental plant lovers because they exhibit an array of leaf pattern, forms, and colors. The problem, however, is that their unique colors and patterns likely change over time. In this regard, zeoponic PGM, made from zeolite mixed with other materials such as compost and cocopeat, and macro- and micronutrients offers a viable solution. Thus, this study aimed to find the appropriate kind and dosage of fertilizers making up the proper formulation of the PGM to support the desired growth and lasting appearance of variegated plants. Pot trials in the research greenhouse were conducted in a two factor, completely randomized design (CRD). The first factor was plant type - Epipremnum aureum variegata and Peperomia obtusifolia variegata. The second factor was a combination of kind and dosage of macro- and micronutrients those were added to the zeoponics. Plant growth and aestetic parameters were observed, and the chemical properties of the PGM were analyzed. The results showed that the best micro fertilizer and dosage for Epipremnum aureum variegata was Fe-EDTA 0.00096 g/l + Cu-EDTA 0.00067 g/l + Mn-EDTA 0.00269 g/l + Zn-EDTA 0.00167 g/l, while for Peperomia obtusifolia variegata, the best fertilizer dosage was Fe-EDTA 0.00038 g/l + Cu-EDTA 0.00027 g/l + Mn-EDTA 0.00108 g/l + Zn-EDTA 0.00067 g/l.

PENGARUH PEMBERIAN PUPUK KASCING TERHADAP KETERSEDIAAN NITROGEN PADA BERBAGAI JENIS TANAH DAN SERAPAN NITROGEN OLEH PAKCOY (Brassica rapa L.)

Nitrogen is a primary macro nutrient needed by plants and has an important role in plant growth. Regosols, Latosols, and Grumusols are soils that have the potential as a medium for plant growth, with different characteristics and levels of productivity and are constrained by soil nitrogen. Application of nitrogen-rich vermicompost as an alternative to overcome the problem of the three soils. The research aimed to determine the available nitrogen content and nitrogen absorption of pakcoy by adding vermicompost on Regosols, Latosols, and Grumusols. The research used a split-plot design with the main plot in the form of soil types (T1 = Regosols, T2 = Latosols, and T3 = Grumusols) and a subplot in the form of a dose of vermicompost fertilizer (K0 = 0 t ha-1, K1 = 10 t ha-1, K2 = 20 t ha-1, and K3 = 30 t ha-1) so there are 12 treatments and repeated three times. The results showed that the application of vermicompost to Regosols, Latosols, and Grumusols increased total N, available N, organic carbon, cation exchange capacity, plant height, fresh weight, dry weight, plant N, and plant N uptake. The dose of vermicompost 20 t ha-1 was the optimum dose for the parameter of N availability.

Effect of Microbial Fertilizer on The Development of Pepper (Capsicum annuum L.) Seedlings Exposed to Salt Stress

Salinity is an important abiotic stress factor that negatively affects plant growth and yield. The study, the effect of microbial fertilizer containing Bacillus subtilis bacteria, commercially named Subtima, on salt stress in pepper was observed. Two different saline solutions (100 mM and 200 mM) were prepared to create salt stress in the plant growing medium. The fertilizer solution was applied to the plants in 4 different concentrations (300, 400, 500 and 600 ppm) from the leaves in the form of a spray. Morphological parameters such as plant height, stem length, leaf length, leaf width, and petiole length were measured. It was found that salt stress resulted in a decrease in plant morphological characteristics compared to the control group (0 mM salt + 0 ppm fertilizer). It was found that the most effective fertilizer dose to increase plant height (25.23 cm) at 100 mM salt stress was 400 ppm. At 200 mM salt stress, it was found that the most effective fertilizer dose for increasing plant height (22.67 cm) was an application of 300 ppm application. In general, fertilizer applications were found to be effective in reducing the negative effects of salt on the morphological traits studied.

Specific features of <i>in vitro</i> micropropagation of various representatives of the genus <i>Rhododendron</i>

One of the best plants for landscaping urban areas are representatives of the genus Rhododendron L. However, there is the problem of obtaining planting material because traditional propagation methods are inefficient or take a lot of time and resources. In vitro micropropagation can be a solution to this problem. The research objects were Rhododendron Helsinky University, Rhododendron hybrid Marianna v. Weizsacker, and Rhododendron caucasicum var. Rosea. Three variants of Woody Plant Medium (WPM) were used for the experiment: with the addition of benzylaminopurine/indolylbutyric acid or naphthylacetic acid/kinetin in the proportion of mg/l, and a control variant without hormones. The analysis of the effect of different concentrations of phytohormones has demonstrated that for different representatives there are specific combinations of growth regulators. For Rh. caucasicum var. Rosea the hormone-free medium was the most suitable for plant growth as well as the appearance of shoots of order II. For Rh. hybrid Marianna v. Weizsacker, the optimal medium for plant growth was also a hormone-free medium, but the addition of naphthylacetic acid / kinetin enhanced the tillering. The presence of benzylaminopurine / indolylbutyric in the medium had a negative effect on the species and the hybrid. The use of these hormones for Rh. Helsinky University resulted in stimulation of growth and tillering of the plant, while naphthylacetic acid / kinetin hormones caused a depressing effect.

THE IMPACT OF RICE HUSK ASH (RHA) AS SOILLESS GROWING MEDIUM ON SAWI CAIXIN GIANT (Brassica parachinensis) GROWTH PERFORMANCE

The Sustainable Development Goal 2 (SDG 2), which aims to end hunger, enhance nutrition, and support sustainable agriculture, places a high priority on food security. The amount of rice husk ash (RHA) produced by the process of burning rice husks has increased over time, causing environmental pollution. In modern soilless agriculture, RHA has a significant potential to be used as a fertile and nutrient-rich medium. The Zero Energy Soilless Agriculture (ZESA) System is a revolutionary concept for horticultural plants that might utilize RHA as a soilless growing medium. The effect of growing medium ratio of cocopeat and RHA on plant growth performance of sawi caixin giant (Brassica Parachinensis) using ZESA system over 35 days was investigated in this study. Three different treatments, T1 (1:0), T2 (1:1), and T3 (3:1), on the growing medium ratio of cocopeat and RHA were carried out. The treatments were set up in four replicates of two individuals each using a randomised full block design. The data of plant Growth parameters such as the number of leaves and plant height were recorded every 7 days, and the fresh weight of the plants was taken on harvesting day. FTIR analysis and an elemental analyzer were used to characterise the chemical analyses of cocopeat, RHA, and fertiliser. As shown by the results, T3 treatment increased all plant growth performance parameters compared to T1 control treatment, with a value of 12.02 cm for plant height, 10 leaves, and 33.75g of fresh weight. The plant growth performance of Brassica parachinensis was improved by using a 3:1 ratio of 25% RHA as a soilless growing medium couple with application of rich nitrogen X and Y fertilisers using the ZESA System. Finally, RHA has the potential to be used as a soilless growing medium for many horticulture plants using the ZESA System.

PEMANFAATAN AQUAPONIK SEBAGAI TEKNOLOGI BUDIDAYA IKAN NILA DAN SAYURAN YANG MENDUKUNG PERTANIAN BERKELANJUTAN DI DESA KAYANGAN, KECAMATAN KAYANGAN, KABUPATEN LOMBOK UTARA

This introduction to aquaponic planting techniques aims to provide examples of the application of advanced and sustainable agricultural technology to the people in Kayangan village, Kayangan sub-district, North Lombok district (KLU). This activity was carried out from December 2022 to February 2023 at the Bagek Kembar hamlet, Kayangan. The fish used were 60 days old fish seeds with a size of 10 cm x 5 cm which were reared in a 4x3 m tarpaulin container. The plant growth media used is in the form of used foam taken from one of the residents' houses with a size of 5 cm. Placement of the planting media uses used plastic cups and used bottles as containers for placing plastic cups. The vegetables used in making this aquaponics are mustard greens, lettuce and pakcoy. The nutrients used to support plant growth are in the form of fish manure and some additional organic nutrients which are made independently using organic waste from the kitchen. The results of using aquaponic technology as a cultivation technology show that the plants grow but the leaves of the plants turn yellow and the fish in the pond can grow large.

Investigating spatial relationship of soil capability and agricultural land management in Cugenang District, Cianjur Regency

Soil as a medium for plant growth is the most important factor in agriculture. Soil capability is closely related to soil fertility which describes soil productivity in producing optimal agricultural production. Cugenang District is located in Cianjur Regency, which has abundant rice crops. Cugenang District also experiences changes in land use and disasters that can decrease the land’s ability. This study aims to map and analyze the capability of the soil and land management of paddy fields and the relationship between the two. This quantitative research uses spatial, statistical, and descriptive analysis. Data were collected by observation, soil sampling, interviews, and secondary data sourced from related institutions. The collected data will be processed using statistical tests and geospatial technology using ArcGIS 10.8 to visualize soil capability and land management of paddy fields geographically. The weighted overlay technique’s spatial analysis results show that most paddy fields have medium and low soil capability. Meanwhile, high soil capability for paddy fields is mostly found in high areas of Cugenang District. The land management of paddy fields is calssified into two combinations. The first combination is between vegetative conservation and fertilization. The second combination is between vegetative conservation, mechanics conservation, and fertilization. Statistical test using chi-square shows a strong relationship between soil capability and land management. The results of this study indicate that the majority of paddy fields with medium soil capability use three methods of land management techniques, while paddy fields with low soil capability use two methods of land management techniques.

SOME MORPHOLOGICAL TRAITS OF TOMATO PLANTS UNDER THE INFLUENCE OF THE ADDITION OF PHOSPHATE ROCK AND SODIUM CHLORIDE AND THEIR INTERACTIONS

A (Factorial experiment), Expermant design was Completely Randomized (C.R.D.),2 × 4 × 3, which included 24 experimental units. It was carried out, during the growing season 2017-2018, in one fieldes of the Botanical Garden of the (Department of biology), in the College (Education for Pure Sciences - Ibn Al-Haytham), University of Baghdad. The research aimed to find out the effect of phosphate rock added to the plant growth medium, at the level of 5 grams, and the zero level that is adding phosphate rock (as a source of the element phosphorus) on some vegetative characteristics of the tomato plant, namely plant height, root length, wet and dry weight of the root and shoot group, Tomato plants grown in medium to which sodium chloride solution was added, and at concentrations of 50, 100 and 150 (mM.L-1), as well as the control treatment, which is the zero concentration of NaCl. The study confirmed the positive effect of adding phosphate rock, increasing the averages and values of the studied traits, increasing the plant's ability to withstand the stress of sodium chloride when adding phosphate rock, and reducing the effect of sodium chloride, which causes a significant decrease in the studied plant traits

Correlation of pesticide ecotoxicity with clay mineral dispersion effect on adsorption and ozonation – An approach through impact assessment on Lemna minor

An unprecedented approach allowed correlating the pesticide fate in clay-containing media under air exposure with their ecotoxicity. This constitutes the novelty of this work and involves the study of the toxicity of ozonized pesticide-containing waters towards an aquatic plant, Lemna minor. The behavior of diazinon (DAZ) and atrazine (ATR) in natural clay-containing media was simulated in plant growth media fulfilling the Swedish Institute for Standards (SIS) containing Na+ and Fe2+-exchanged montmorillonite (Mt). The exchangeable cation was found to influence the pesticide ozonation and toxicity towards Lemna minor. Pesticide interactions appear to promote high catalytic surface through a compromise between low pH and high Mt dispersion. These results provide valuable findings for predicting pesticide ecotoxicity according to their natural oxidative degradation in the host clay suspension.

Application of organic wastes to subsoil materials can provide sustained soil quality in engineered soil covers for mine tailings rehabilitation: A 7 years study

Improper disposal or poor management practices at mine Tailings Storage Facilities (TSF) can give rise to fugitive emissions with risk to both the surrounding environment. Establishing sustainable vegetation covers (rehabilitation) on TSFs is a critical objective and effective management strategy to mitigate pollution risk. Although direct revegetation is a potential strategy, tailings can exhibit properties such as extreme pH, salinity, elevated metal content, deficiency of nutrients and organic matter that inhibit vegetation establishment and necessitate the provision of a cover soil medium (≥ 30 cm). This requires a high amount of topsoil sourcing, which is often in limited supply at mine sites because of degradation, contamination, or previous removal. Moreover, materials often used as a soil cover for tailings may not favour plant establishment and development due to the poor soil structure and the low level of organic matter and nutrient content.Thus, improvement of substrate physiochemical characteristics by using organic and/or inorganic amendments is needed to promote plant establishment and drive soil processes. While several studies have assessed the feasibility of different plant growth media (soils) they are often based on short-term evaluation in greenhouse and lack the longer term implications of field based studies.Soil cover materials were evaluated using 1 m3 plots at a Pb/Zn TSF. Treatments included tailings, subsoil and subsoil amended with Compost like Output (CLO) and Spent Mushroom Compost (SMC). Following 7 years' revegetation, soil samples were taken at two depths (0–10 cm and 10–20 cm) and pH, salinity (EC), structure, nutrient and metal content were determined. Vegetation nutrient content was determined after 1 yrs. growth (2015) and again at 7 yrs. (2021).Bare tailings and subsoil displayed poor physico-chemical properties, whereas SMC or CLO amendment, improved physical characteristics and nutrient content both in soil and in vegetation, showing that the benefits of organic amendment to subsoil materials for rehabilitation are effective in the long-term. Moreover, results showed a higher content of C, N and P in all treatments at the depth 0–10 cm than at 10–20 cm, highlighting the role played by the rhizosphere. While lower vegetation nutrient content was recorded in the in the 2021, in some cases below deficiency criteria, results highlight the need for rehabilitation criteria specific rather than applying standard agronomy guidelines.

Marul bitkisinin (Lactuca sativa L.) akuaponik sistemde gıda güvenliği açısından değerlendirilmesi

We determined the number of coliform bacteria, Escherichia coli, yeast, and molds that may occur in the system, and the quality of lettuce grown in aquaponics for consumers from sensory, colour, and texture points of view. The amount of yeast and mold in the plant growing medium (hydroton) and water was 4.67 log CFU/cm2 and 2.25 log CFU/mL at the end of the six-week experiment, respectively. The number of coliform bacteria and E. coli in the growing medium and in the system water was found to be 2.57 log CFU/cm2 and 3.46 log CFU/mL for coliform, 0.75 log CFU/cm2 0.31 log CFU/mL for E. coli, respectively. Organisms that pose a risk to food safety, accumulate in the culture media. After the harvest, lettuce cultured in the aquaponic system (AP) was compared with the lettuce cultured in soil (SC). According to the results, AP lettuce was found to have darker colors (Lightness: 56.4 AP, 49.09 SC, p<0.05), harder (Hardness: 209.3 AP, 153.7 SC, p<0.05), and slightly appetizing (Sensory analysis overall liking: 8.4 AP, 7.7 SC) than SC. In conclution, aquaponic systems are much more preferable in terms of sensory quality and consumer preferences than soil-based production systems.

Phenolic Compound Production Increased In Vitro Regenerated Cichorium intybus L.

Chicory (Cichorium intybus L.) is a low-height perennial or biennial herb from the family of Asteraceae. Investigation of different in vitro regeneration strategies of Cichorium intybus and increasing the number of secondary metabolites in vitro regenerated plant samples were the aims of the research. Callus and plant regenerations were achieved in basal plant growth media supplemented with plant growth regulators (PGRs). Whole plant regeneration was carried out by direct organogenesis from leaf explant in Murashige and Skoog (MS) and B5 media supplemented with naphthalene acetic (NAA) acid and indole-3-butyric acid (IBA). The highest callus quantity was produced in MS medium supplemented with indole-3-acetic acid (IAA) and benzyl amino purine (BAP). The combination and concentrations of PGRs used in MS and B5 media not only provided root and shoot formation with callus, but also caused a change in the amounts of phenolic components. In addition, some PGRs used caused an increase in the number of phenolic compounds in callus and shoots developed from the leaf explant. When plants that grow in vitro and in vivo are compared with each other, it has been determined that plants grown in vivo contain higher amounts of some phenolic compounds. In vivo and in vitro samples were extracted in ethanol/water (80:20 v/v). The analysis of phenolic compounds (caftaric, chicoric, and chlorogenic acids and esculin) were performed in high-performance liquid chromatography (HPLC) and inulin was in UV spectrophotometry. The caftaric and chlorogenic acids and inulin concentrations were higher in vivo samples than that in vitro. Contrarily, esculin, and chicoric acid concentrations were higher in the in vitro regenerated samples. The higher concentration of valuable compounds in the in vitro regenerated samples, especially in callus tissue, gives hope for large-scale production of secondary metabolites under laboratory conditions.

Constructed Technosols as a Soil Rebuilding Technique to Reclaim Abandoned Limestone Quarries in the Mediterranean Region: A Field Study

Soil rebuilding represents a major challenge in the recovery of abandoned quarries. In this study, we explored the possibility of using reconstructed Technosols, to achieve soil rebuilding goals at an abandoned quarry site. We first investigated the use of a mixture containing commercial manure and limestone debris (LD) as pedotechnomaterials for an “ad hoc” (re)constructed Technosol (CT), for the recovery of an opencast limestone quarry in one of most concentrated quarry areas in the world. In a field experiment, we tested and monitored different pedotechnosystems (PTSs) made up of constructed Technosol + pasture species + different Mediterranean plant species. Specifically, a control (CT, without any additional treatments) was compared to treatments with organic amendment (CTOA) and conventional fertilizers (CTCF). Data were collected over a 12-month period and included crop performance, plant nutritional state, soil physical-chemical parameters, and metabolites. Analysis of variance compared differences among treatments, while factor analysis (FA) interpreted multiple relationships while explaining observed variability. Results showed that CTOA had better soil physical-chemical properties, greater plant growth, and overall superior agronomic performances compared to all other treatments due to the improved substrate conditions. According to FA, these results appear related to the creation of fertile soil conditions, with most of the investigated metabolites (i) playing a pivotal role in observed outcomes, together with (ii) a clear potential in being considered as a reliable fingerprint for investigating plant responses in constructed PTSs. The proposed pedotechniques in CTOA development show a great potential for the full recovery of abandoned limestone quarries in degraded Mediterranean areas by providing an excellent medium for plant growth, facilitating environmental reclamation.

Thermal treatment of petroleum-contaminated marine sediment according to oxygen availability and temperature: Product quality as a potential plant-growth medium

The sustainable management of dredged sediment from contaminated sites needs to consider the end-use of the treated sediment. In this regard, modifying conventional sediment treatment techniques to generate a product that is suitable for a range of terrestrial uses is necessary. In the present study, we evaluated the product quality of treated sediment as a potential plant-growth medium following the thermal treatment of marine sediment contaminated by petroleum. The contaminated sediment was subject to thermal treatment at temperatures of 300, 400, or 500 °C, and no, low, or moderate oxygen availability, and the resulting treated sediment was analyzed in terms of its bulk properties, spectroscopic properties, organic contaminants, water-soluble salts and organic matter, and the leachability and extractability of heavy metals. All operational combinations for the treatment process reduced the total petroleum hydrocarbon content of the sediment from 4922 mg kg−1 to lower than 50 mg kg−1. The thermal treatment process stabilized the heavy metals in the sediment, reducing the zinc and copper concentration by up to 58.9% and 89.6%, respectively, in the leachate from the toxicity characteristic leaching procedure. The hydrophilic organic and/or sulfate salt byproducts of the treatment were phytotoxic, but these can easily be removed by washing the sediment with water. By combining the sediment analysis results with experimental data from barley germination and early-growth tests, the end product was found to be of higher quality when higher temperatures and lower oxygen availability were employed in the treatment process. These findings demonstrate that it is possible to retain the natural organic resources of the original sediment by optimizing the thermal treatment, thus ensuring a suitably high product quality for use as a plant-growth medium.

High Efficiency Regeneration System from Blueberry Leaves and Stems.

The main propagation approach is tissue culture in blueberries, and tissue culture is an effective and low-cost method with higher economic efficiency in blueberries. However, there is a lack of stable and efficient production systems of industrialization of tissue culture in blueberries. In this study, the high-efficiency tissue culture and rapid propagation technology system were established based on blueberry leaves and stems. The optimal medium for callus induction was WPM (woody plant medium) containing 2.0 mg/L Forchlorfenuron (CPPU), 0.2 mg/L 2-isopentenyladenine (2-ip) with a 97% callus induction rate and a callus differentiation rate of 71% by using blueberry leaves as explants. The optimal secondary culture of the leaf callus medium was WPM containing 3.0 mg/L CPPU with an increment coefficient of 24%. The optimal bud growth medium was WPM containing 1.0 mg/L CPPU, 0.4 mg/L 2-ip, with which the growth of the bud was better, stronger and faster. The optimal rooting medium was 1/2 Murashige and Skoog (1/2MS) medium containing 2.0 mg/L naphthylacetic acid (NAA), with which the rooting rate was 90% with shorter rooting time and more adventitious root. In addition, we established a regeneration system based on blueberry stems. The optimal preculture medium in blueberry stem explants was MS medium containing 2-(N-morpholino) ethanesulfonic acid (MES) containing 0.2 mg/L indole-3-acetic acid (IAA), 0.1 mg/L CPPU, 100 mg/L NaCl, with which the germination rate of the bud was 93%. The optimal medium for fast plant growth was MS medium containing MES containing 0.4 mg/L zeatin (ZT), 1 mg/L putrescine, 1 mg/L spermidine, 1 mg/L spermidine, which had a good growth state and growth rate. The optimal cultivation for plantlet growth was MS medium containing MES containing 0.5 mg/L isopentene adenine, with which the plantlet was strong. The optimal rooting medium for the stem was 1/2MS medium containing 2.0 mg/L NAA, with which the rooting rate was 93% with a short time and more adventitious root. In conclusion, we found that stem explants had higher regeneration efficiency for a stable and efficient production system of industrialization of tissue culture. This study provides theoretical guidance and technical support in precision breeding and standardization and industrialization in the blueberry industry.