Mixture Of Topsoil Research Articles

In Situ Use of Mining Substrates for Wetland Construction: Results of a Pilot Experiment.

This paper evaluates an experimental wetland as part of a pilot soil reclamation project in a mining area. The wetland was constructed using materials of mining origin from the area; most reactive materials of acid pH were stabilised using limestone filler. The study selected macrophytes that are tolerant to potentially toxic elements (PTEs) and resistant to salinity, namely Phragmites australis, Juncus effusus, and Iris pseudacorus. These macrophytes were then placed in pots containing substrates composed of different mixtures of topsoil, peat, and mining waste (black or yellow sand). A thorough analysis of the physicochemical and mineralogical characteristics of the materials included studies of PTE mobilisation. This study emphasises the significance of the rhizosphere in directing the transfer of PTEs to the plant and the correlation between the substrate and the development of plant defence mechanisms, such as the formation of Fe-plates. Scanning electron microscopy was used to highlight these aspects and validate the results of the analytical determinations. These wetlands can be proposed as a phytoremediation strategy for areas affected by mining and maritime influence. They are easy to construct and remain stable, providing important ecosystem services such as the natural attenuation of acid mine drainage, support for vegetation development and fauna, and a clean ecosystem.

Enhancing Native Plant Establishment in Mine Tailings under Drought Stress Conditions through the Application of Organo-Mineral Amendments and Microbial Inoculants

The implementation of phytoremediation strategies under arid and semiarid climates requires the use of appropriate plant species capable of withstanding multiple abiotic stresses. In this study, we assessed the combined effects of organo-mineral amendments and microbial inoculants on the chemical and biological properties of mine tailings, as well as on the growth of native plant species under drought stress conditions. Plants were cultivated in pots containing 1 kg of a mixture of mine tailings and topsoil (i.e., pre-mined superficial soil) in a 60:40 ratio, 6% marble sludge, and 10% sheep manure. Moreover, a consortium of four drought-resistant plant growth-promoting rhizobacteria (PGPR) was inoculated. Three irrigation levels were applied: well-watered, moderate water deficit, and severe water deficit, corresponding to 80%, 45%, and 30% of field capacity, respectively. The addition of topsoil and organo-mineral amendments to mine tailings significantly improved their chemical and biological properties, which were further enhanced by bacterial inoculation and plants’ establishment. Water stress negatively impacted enzymatic activities in amended tailings, resulting in a significant decrease in acid and alkaline phosphatases, urease, and dehydrogenase activities. Similar results were obtained for bacteria, fungi, and actinomycete abundance. PGPR inoculation positively influenced the availability of phosphorus, total nitrogen, and organic carbon, while it increased alkaline phosphatase, urease (by about 10%), and dehydrogenase activity (by 50%). The rhizosphere of Peganum harmala showed the highest enzymatic activity and number of culturable microorganisms, especially in inoculated treatments. Severe water deficit negatively affected plant growth, leading to a 40% reduction in the shoot biomass of both Atriplex halimus and Pennisetum setaceum compared to well-watered plants. P. harmala showed greater tolerance to water stress, evidenced by lower decreases observed in root and shoot length and dry weight compared to well-watered plants. The use of bioinoculants mitigated the negative effects of drought on P. harmala shoot biomass, resulting in an increase of up to 75% in the aerial biomass in plants exposed to severe water deficit. In conclusion, the results suggest that the combination of organo-mineral amendments, PGPR inoculation, and P. harmala represents a promising approach to enhance the phytoremediation of metal-polluted soils under semiarid conditions.

Application of organic fertilizer for improving soybean production under acidic stress

The presence of acidic soil in rural areas poses difficulties for agricultural production. One factor regulating soil pH is the overuse of inorganic fertilizer. The increased use of fertilizers in soybean production not only raises sustainability concerns but also contributes to soil acidity. Therefore, the use of organic fertilizer could offer a solution for addressing both issues related to soil acidity and sustainability. The purpose of this study was to investigate the manipulation of soil pH using organic fertilizer for soybean production under acidic stress. The planting medium, consisting of a mixture of topsoil, rice husk charcoal, and organic fertilizer (in a ratio of 2:1:1), was supplemented with 0.5 ​g of NPK fertilizer as a basal treatment in each planting medium. To regulate the soil acidity to pH 4, we added FeSO4 and allowed the mixture to incubate for 30 days. The results demonstrate that the application of three types of organic fertilizers chicken manure (P1), oil palm empty bunch fertilizer (P2), and vermicompost (P3) positively impacts the growth of three soybean varieties. The findings indicate that the application of P2 organic fertilizer can increase vegetative growth almost 50% in soybeans on acidic soil, including plant height, leaf count, and root length. Meanwhile, applying P3 organic fertilizer can boost reproductive growth responses in soybeans on acidic soil, such as pod number (from around 0-4 unit to 42–51 unit), grain number (from around 0-5 unit to 88–90 unit), and grain weight (from around 0–0.37 ​g to 12–25 ​g). Organic fertilizer has the potential to regulate soil pH, promoting higher yields of soybeans under acidic stress.

Selection of best compound fertilizer amended potting mixture for successful growth of black pepper (<em>Piper nigrum l.</em>) hybrid (“Dingirala”) nursery plants

Black Pepper, Piper nigrum L.) is a perennial, evergreen, climbing vine and it is widely used as a spice and flavoring agent in the food industry and ayurvada medicine throughout the world. Therefore, continuous supply of pepper is important for the sustainability of these sectors. Pepper is usually propagated vegetatively using stem cuttings. Cuttings are planted in polythene bags filled with a mixture of equal parts of topsoil, cow dung, sand, and coir dust. Scarcity of cow dung and expensiveness resulted with huge demand are the limiting factors in commercial production of pepper. Incorporation of nitrogen and phosphorus containing fertilizers to potting mixture in the absence of cow dung may at least supply plant nutrients which highly essential for early growth of plants. Therefore, this study was carried out to investigate the effect of different compound fertilizer for nursery plants of P. nigrum L, hybrid “Dingirala” in the absence of cow dung in the potting mixture. Four different levels (1, 2, 3, 4 g per pot) of four different compound fertilizers were taken as treatments such as T1- Yara Complex (N:P:K 12:11:18), T2- Yara Grower ( N:P:K 21:7:14), T3- NPK Balance (N:P:K 15:15:15) K as SOP, T4- NPK Balance (N:P:K 15:15:15) K as MOP and T5 a phosphate fertilizer Di-ammonium phosphate (DAP) (N:P:K 18:46 :0). All were mixed into a modified potting mixture of topsoil: sand: coir dust 2:1:1 without cow dung. Control was the potting mixture already recommended by Department of Export Agriculture (top soil: sand: coir dust: cow dung, 2:1:1:1) without inorganic fertilizer. Each treatment contained three replicates per treatment. Complete Randomized Block Design (RCBD) was the experimental design and each block consisted with 50 plants. Two nodal cuttings of Black pepper hybrid Dingirala were planted and maintained in a propagator under a net house at central research station Matale (IM3a). After 105 days from establishment, survival percentage, growth parameters such as shoot length (cm), number of leaves and shoot dry weight (g) were measured. Soil parameters such as soil pH and EC and total N%, P% and K% of tissues were analyzed. Significantly highest (P<0.05) survival rate (91%) was recorded from recommended potting mixture used as control in this experiment and cuttings treated with 1g of Di-ammonium phosphate. Significantly highest (P<0.05) shoot length (39.1cm) was recorded from cuttings treated with 1g of Yara complex fertilizer (N:P:K 12:11:18) and Significantly highest (P<0.05) number of leaves (9.0) was recorded from cuttings treated with 1g of DAP fertilizer.Therefore, cuttings planted with top soil: sand: coir dust: cow dung, 2:1:1:1 is the best potting mixture and in absence of cow dung with normal potting mixture with 1g of Di-ammonium phosphate excelled all compound fertilizers in terms of overall growth, soil and leaf nutrient parameters of Hybrid "Dingirala" pepper nursery plants over the first 105 days after establishment.

The growth impact of Capsicum annuum crops in hydrogel incorporated media

Increasing food and water security via sustainable agriculture is vital, particularly in light of climate change. Researchers and farmers have recently shown a great deal of interest in the agricultural applications of hydrogels. This research aims to evaluate the impact of hydrogel on Capsicum annuum crop productivity and irrigation water use effectiveness. In a polybag containing a specifically formulated mixture of hydrogel and topsoil, the pepper variety cv Bara was contained. The use of 20%, 40%, 60%, 80%, and 100% biodegradable hydrogel doses per plant was also investigated. The treatment schedule was established using a random complete block strategy. Investigated factors included water usage, irrigation frequency, plant height, leaf number, leaf area, and leaf area index. According to the study’s findings, 40 percent hydrogel and 60 percent topsoil per plant produced the optimum growth characteristics. The results of the study indicate that hydrogel able to hold water, circulating water into the media and enhancing the water usage efficiency of pepper crops without affecting plant growth.

Effect of nodal cutting position and plant growth regulator on bud sprouting of Dendrocalamus giganteus Wall. Ex Munro in Uganda

Dendrocalamus giganteus Wall. Ex Munro (giant bamboo) is one of the most economically important bamboo species globally. However, propagation of Dendrocalamus giganteus from seed is hampered by the duration it takes to flower – making the large-scale production of planting stock for this valuable species untenable. This study was conducted under greenhouse conditions to determine the optimal doses of indole-3-butyric acid (IBA) and culm cutting position to propagate D. giganteus. Cuttings from the top, middle and basal culm positions were treated with different concentrations of Indole-3-Butyric Acid (0.6 %, 0.8 % and 1.0 %) and a control with distilled water. A mixture of top forest soil and sand in a ratio of 2:1 was used as a growth medium. The experiment was set up in a Complete Randomized Factorial Design (CRFD). Cuttings were monitored for the number of bud sprouts over 18 weeks. Results indicated that cuttings’ position and concentration of IBA greatly influenced the sprouting of D. giganteus. The highest bud sprouts were obtained for 0.6 % IBA and cuttings from the basal position. Bud sprouting was lowest in the control and cuttings from the top position. We conclude that while propagating D. giganteus by culm cuttings, basal cuttings and 0.6 % IBA should be encouraged.

Effect of media on the percentage of Cratoxylum arborescens cutting

Gerunggang (Cratoxylum arborescens Blume.) is one of native peat swamp species which good potential for pulp material and rehabilitation. One factor affecting the success of vegetative propagation is rooting media. The objectived of this study was observed the suitability of four rooting medium for gerunggang cuttings i.e: river sand, mixture of peat+ rice husk (3:1), mixture of top soil+rice husk (3:1), and mixture of cocopeat+rice husk (2:1). A number of 20 gerunggang cuttings with 4 replication were tested at four rooting media during 16 weeks observation period. Some parameter were observed i.e: number of shoots, leaves and roots per cutting, length of primary root (cm), rooting speed, rooted percentage (%), and survival percentage (%). Different rooting media significantly affect (p<0.01) on number of buds per cutting and length of primary root. However, the type of rooting media did not significantly affect (p>0.05) to the number of leaves and roots per cutting, rooted percentage (%) and survival percentage (%). High rooting percentage was achieved by media topsoil+ricehusk with average of 67.50%, while the lowest percentage was obtained peat+ricehusk medium with average of 38.75%. A mixture of topsoil+rice husks (3:1) is a best medium for early growth of gerunggang cutting which indicate by best number of buds, leaves and roots per cutting, rooted percentage (%) and survival percentage (%). Survival rate of cutting in this research is ranging from 56.25% - 77.50%.

EFFECT OF PRE-SOWING TREATMENT ON SEED GERMINATION OF LOHAKATH (XYLIA KERRII CRAIB &amp; HUTCH.)

Lohakath (Xylia kerrii Craib &amp; Hutch.), a valuable timber species in Bangladesh, belongs to the family Leguminosae. Morphology of fruits, seeds and the effect pre-sowing treatments of seeds were studied. The average length, breath and thickness of fruits were found 13.3, 5.3 and 0.8 cm respectively and those of seeds were 1.4, 0.3 and 0.3 cm respectively. Number of seeds per kilogram was 5000-5400. The germination test was done by sowing the seeds in polybags (4 cm x 6 cm) filled with a mixture of topsoil, coconut husk compost, coarse sand and fine sand in the ratio of 3:4:1:1. The highest germination percentage (98%) was found in scarification with sand paper. The lowest germination percentage (53%) was found in control. About 87% was found in hot water (80 °C) immersion (10 minutes), 84% was found in 80% concentrated H2SO4, 63% was found in immersion in cold water (4 °C) for 12 hours. As the use of sulphuric acid and scarification techniques are somewhat risky and trouble some, therefore, pre-sowing treatment of Lohakath seed for germination in rural Bangladesh could be hot water immersion method.

UPTAKE AND DISTRIBUTION OF RADIOSTRONTIUM IN TOMATO TREATED WITH ARBUSCULAR MYCORRHIZAL FUNGI.

Arbuscular mycorrhizal fungi (AMF) were inoculated into the root system of edible tomato plants to investigate their effect on the uptake and distribution of strontium radionuclide in the tissues of plants grown under laboratory conditions. The experiments were carried out in a sterile mixture of topsoil and sand, where in one series of experiments contaminated soil with 85Sr was used. Seeds were inoculated with a mixture of AMF at sowing, the second, control series was without application of AMF. Determination of radioactivity in soil and in different parts of tomato plants was carried out by gamma-spectrometric measurement. The obtained results and statistical analysis indicated a significant association between AMF inoculation of plants and the change in the distribution of 85Sr. The presence of AMF reduced the translocation of 85Sr from the root system to the aerial parts of tomato plants.

Propagation of agroforestry tree species by airlayering: a case study of Canarium schweinfurthii Engl. in the Western Highlands of Cameroon

Objective: As a contribution to the domestication of Canarium schweinfurthii (Black olive tree), the present study examined its potential for clonal propagation by air-layering. Methodology and Results: Three substrates Topsoil, Sawdust and mixture of Sawdust and Topsoil in a 1:1 (v/v) ratio] and five concentrations (0, 1, 2.5, 5 and 10 g/l) of exogenously applied indole butyric acid (IBA) were tested for their effects on the rooting of air-layers. Results showed that the percentage of rooted layers and the mean number of roots per rooted layer were significantly (p ˂ 0.001) influenced by substrate and IBA concentration, whereas the layers’ mortality rate was influenced only by substrate (p ˂ 0.001). The highest percentage of rooted layers (78.57 ± 7.78%) was recorded with the combination of Sawdust substrate and 5 g/l IBA. The same treatment combination resulted in the highest mean number of roots per rooted layer (34.95 ± 0.76). The lowest mortality rate of layers (6 ± 1.94%) was recorded with Sawdust substrate. Conclusion and application of findings: C. schweinfurthii is amenable to vegetative propagation through air-layering technique. For prolific rooting of air-layers, Sawdust substrate and application of 5 g/l IBA are recommended. With the increasing demand for C. schweinfurthii fruits, these study findings would contribute to rapid and mass propagation of this multifunctional indigenous tree species which have suffered neglect in research. Selecting trees with desirable traits and propagating them asexually using simple and inexpensive method as described in this work would improve establishment of this plant whose fruits trade raises the living standard of many populations in Western and Central Africa. Keywords: Canarium schweinfurthii, Domestication, Non-timber forest products, Vegetative propagation, Western Highlands of Cameroon

GROWTH RESPONSES OF SACHA INCHI BEAN SEEDS (Plukenetia volubilis L) ON VARIOUS ORGANIC MATERIAL SOURCES

Sacha inchi is a creeping perennial herb plant that belongs to the Euphorbiaceae family. Sacha inchi, or Plukenetia volubilis is a perennial plant with large, oil-filled seeds. sacha inchi plants began to be widely cultivated. However, in practice it is still planted directly in the field, without going through the nursery first, so the quality of the plants produced varies greatly. Seeding is a process that determines the quality of the plants to be cultivated. Planting media is the media used to grow plants, where roots or roots will grow and develop. A good planting medium must meet requirements such as not containing pest and disease seeds, free of weeds, able to hold water. This study aims to see the effect of the mixture and to get the best mixture of organic matter that supports the growth of Sacha inchi seedlings. This research was conducted from June to August 2022. The research method used was a Randomized Block Design (RAK) with 5 treatments consisting of: Top soil : sand (A), Top soil : sand : burnt husks (B), Top soil : sand : goat manure (C), top soil : sand : bamboo leaves (D), top soil : sand : leftover crickets (E). Data analysis with F test and further test with BNT test level of 5%. Giving organic matter shows better growth than without giving organic matter. Mixture of top soil, sand, and crickets growing media showed optimal growth in number of leaves, number of perfectly opened leaves, widest leaf width, longest leaf length, plant height, fresh weight of plants, and fresh weight of roots.

Seedling Growth of Tectona grandis using Different Potting Mixture

Aims: This study evaluated the influence of 11 potting media compositions on seedling growth and development of Tectona grandis.&#x0D; Study Design: The experiment was set up in a completely randomized design involving ten replicates.&#x0D; Place and Duration of Study: The study was carried out at the Department of Forestry and Wildlife Management Nursery, University of Port Harcourt, Rivers State, Nigeria, between April 2019 and April 2020.&#x0D; Methodology: Ten (10) seedlings per sowing media including topsoil, topsoil and cow dung (2:1, 3:1), topsoil and poultry dung (2:1, 3:1), topsoil and pig dung (2.1, 3:1), topsoil and sawdust (2.1, 3:1), topsoil and mushroom substrate (2.1, 3:1) were selected and transplanted into polybags. Growth parameters (seedling height, root collar diameter, leaf number and biomass (shoot dry weight (SDW), root dry weight (RDW) and total dry weight (TDW)) were determined and subjected to analysis of variance.&#x0D; Results: Seedlings of T. grandis displayed significant differences (p ≤ 0.05) in height, root collar diameter, leaf number and biomass. Among treatments, tallest seedlings were observed in mixture of topsoil and poultry dung (3:1), at months 1 to 3 and in mixture of topsoil and cow dung (3:1) at months 4 and 5, highest root collar diameter was observed in mixture of topsoil and poultry dung (3:1) and highest leaf number was recorded in mixture of topsoil and poultry dung (2:1 and 3:1) and topsoil and cow dung (2:1 and 3:1) at months 1 to 5. The highest SDW was evident in mixture of topsoil and poultry dung (2:1) while highest RDW and TDW were observed in mixture of topsoil and cow dung (3:1). Lowest height, diameter, leaf number and biomass were recorded in topsoil (control) at months 1 to 5.&#x0D; Conclusion: The results revealed that among the tested mixtures, topsoil and poultry dung and topsoil and cow dung mixtures were the best for seedlings growth of T. grandis.

Germination responses of Cola acuminata (Pal. De Beauv.) seeds to different substrates, photoperiods and dehydration

Cola acuminata (Pal. De Beauv.), one of the many forest tree species which are of socio-economic importance in Western and Central Africa, is still exploited in the wild by subsistence farmers because it has not been domesticated yet. As a contribution to its domestication, the present study aimed at determining germination requirements and desiccation tolerance of seeds. Three substrates (forest topsoil, river sand and mixture of forest top soil and river sand), two photoperiods (12 hours/day and continuous darkness) and dehydration were investigated for their effects on seeds germination percentage. To evaluate the seeds’ tolerance to desiccation, fresh seeds were dried at laboratory temperature for 16 days during which seeds moisture content, seeds germination percentage and electrical conductivity of seeds leachate were monitored at two-day intervals. Results showed that the mean germination percentage recorded on the mixture of forest top soil and river sand (97.2 ± 1.0%) was significantly higher than that recorded on forest topsoil (85.5 ± 4.0%), which was in turn higher than that obtained on river sand (70 ± 1.5%). The effect of photoperiod on germination percentage was not significant (p = 0.112). As response to seeds drying, the mean germination percentage slightly decreased as moisture got lost, then drastically dropped when moisture content was below 45.95 ± 4.2%. Seeds failed to germinate when their moisture content fell below 27.1 ± 2.1%. Electrical conductivity of seed leachate exhibited a highly significant negative correlation with both germination percentage (p ˂ 0.01, r = -0.926) and moisture content (p ˂ 0.01, r = -0.931). It is concluded that the best substrate for C. acuminata seeds’ germination is the mixture of forest top soil and river sand in a 1/1 (v/v) ratio. Cola acuminata seeds are desiccation-sensitive and their storage behavior is recalcitrant. This is a significant constraint for conservation that should be addressed in further researches.Keywords: Cola acuminate, seed germination, photoperiod, desiccation tolerance, moisture content, storage behavior.

Mass Propagation of Nauclea diderrichii (de Willd. &amp; Th. Dur) Merr. Seedlings through Tissue Culture Technique

Nauclea diderrichii is a tree species of economic importance. However, its plantation establishment is limited by inadequate seedling production. Hence, there is ample scope of tissue culture for its mass propagation. Its in vitro plantlets development as affected by media strengths indicated that 100 % seed germination was obtained in full MS basal medium while the least (3.35 %) was from quarter-strength at 8 Weeks after inoculation (WAI). The effects of BAP and NAA assessed on the growth of its sub-cultured plantlets showed that highest number of leaves (17) and adventitious shoots (3) were obtained from MS basal medium supplemented with 0.1 mg/l BAP only. Whereas, highest shoot length (3.61 cm) and average number of roots (5/plantlet) were obtained from the same medium without hormone(s) at 8 WAI. Further sub-culturing into MS with 0.05 mg/l NAA resulted into plantlets having optimum shoot and massive root growth ready for acclimatization in 6 WAI. The plantlets were successfully acclimatized using coconuthusk/ topsoil mixture with 90 % survival.&#x0D; Plant Tissue Cult. &amp; Biotech. 31(1): 51-60, 2021 (June)

Percolation monitoring and water content estimation by Ground Penetrating Radar in a controlled environment

We investigated the percolation of water within a controlled environment in order to recover the EM properties and the internal structure of the materials, and to better understand the drainage processes involved. We implemented an analogue model that accurately replicates a green roof, from the construction materials to the geometry. We acquired several common offset GPR data sets on the entire surface of the model, both before and during different irrigation tests. We separately analyzed variations in the reflected amplitudes and in the EM velocities, the latter of which were calculated by combining the measured thickness of the model with the arrival times of the recorded reflections. The signal amplitudes obtained before and during irrigation are compared in order to estimate the attenuation factor at the different stages of the irrigation process. We use the attenuation factor and the EM velocities to estimate the relative permittivity of the topsoil mixture, from which we then calculate the water content, the porosity, and the relative electrical permittivity of the solid matrix by applying well known empirical formulas. The results were validated by comparing them with independent direct measurements.

Phytoremediation of potentially toxic elements using constructed wetlands in coastal areas with a mining influence.

This paper proposes the use of wetlands as a phytoremediation strategy for areas of mining and maritime influence in the southeast of Spain. Potentially toxic elements (PTEs) tolerant and salinity-resistant macrophytes (Phragmites australis, Juncus effusus and Iris pseudacorus) have been used. The experiment is carried out in an aerobic artificial wetland using representative sediments affected by mining activities in the study area. Selected species were placed in pots containing substrates made with different mixtures of topsoil and/or peat, mining residues (black or yellow sand). After six months, rhizosphere, root and aerial parts were collected. A transfer study of As, Pb, Zn and Cu is performed, determining contents in rhizosphere and plant (aerial and underground part). From these data, the TF and BCF were calculated for each plant in 15 different substrates. The work is complemented by an initial study of scanning electron microscopy (SEM-EDX) of plants. The obtained results indicate a tolerance of the metallophytes to these PTEs, which may favour the obtaining of a naturalized habitat that acts as an effective protective barrier to the ecosystem, that is easy to maintain and that avoid the risk of transfer to the trophic chain. The use of these species can be a complement to the chemical stabilization proposed for the whole area and carried out in experimental plots. Because they are perennial plants, it is necessary to continue with the experiments and obtain results in a longer period of time that allows to evaluate yield and stabilization.

EVALUATION OF POTTING MIXTURES AND PROVENANCE ON EMERGENCE AND SEEDLING GROWTH OF GUM ARABIC (Senegalia senegal [L.] Britton)

The experiment was conducted at the Rubber Research Institute of Nigeria, Gum Arabic nursery Sub-station Gashua, Yobe (120 46’ N longitude 110 00’E and altitude 360m above sea level) to evaluate the effect of potting mixtures and provenance on the emergence and seedling growth performance of gum arabic (Senegalia senegal) in 2017 and 2018. The treatments consisted of eight (8) difference potting mixtures of top soil, river sand cowdung in the ratios (2:0:1, 2:0:3, 2:1:1, 2:1:3, 2:2:1, 2:2:3, 2:3:1, 2:3:3) and two (2) provenance (Yusufari and Gujba). The experiments were laid out in Randomized Complete Design in three (3) replications. Potting mixture showed no significant difference in days to emergence of S. senegal while seeds of Yusufari origin significantly influenced early days to emergence in both years of the study. At three (3) months after sowing (3 MAS) with ratios 2:1:1, 2:3:1 and 2:2:3 though statistically similar, significantly gave superior seedlings height in 2017 and 2018 experimentation with Gujba provenance producing taller seedlings. At 3MAS with ratio 2:1:1, 2:0:1, 2:1:3 and 2:2:1 thought statistically comparable, significantly increased seedling stem diameter, number of primary branches and canopy spread than other ratios in both seasons. Also, at 3MAS potting mixtures of 2:1:1, 2:1:3, 2:3:1 and 2:2:3, thought statistically similar, significantly increased height at first branch and root length more than the other ratios regardless of the study year. The study concluded that Gujba provenance gave superior seedling growth performance in most of the sampling period. The study concluded that potting mixture in the ration 2:1:1 was most appropriate for morphological growth characters of gum Arabic provenances. It is therefore recommended for profitable seedling production in the study area.

Growth, Oxalate and Vitamin C Content of Red Amaranth (Amaranthus tricolor L.) Treated with Salicylic Acid

Red amaranth (Amaranthus tricolor L.) contains phytochemicals that are important for human health, however it also contains oxalate that may cause uric acid problem in human health. This experiment was carried out to evaluate the effect of salicylic acid (SA) on growth, oxalate, chlorophyll, and vitamin C contents in red amaranth. Red amaranth seeds were germinated in a plastic pot containing a mixture of top soil and organic fertilizer. Three week-old seedlings were applied with SA of 0 M (control), 10-8, 10-6, 10-4 or 10-2 M. Five replicates were prepared for each treatment. Growth parameters observed were plant height, fresh weight, and dry weight of plant. The Ca-oxalate crystals density was determined by observing stem section under the microscope. Chlorophyll and oxalic acid content were determined by spectrophotometer method, whereas vitamin C content was determined by titration method. The results showed that plant height and root length were tend to decline by SA application, however SA of 10-6 M significantly increased chlorophyll, carotenoid and vitamin C content. All concentrations of SA applied were able to reduce oxalic acid content and Ca-oxalate crystal’s density in stem. It can be inferred that application of SA generally enhances nutrient quality of red amaranth.

Progress of Soil Fertility and Soil Health Management Research for Arabica Coffee Production in Ethiopia

Soil degradation is one of Ethiopia's most severe concerns, contributing for the country's low coffee production. Researchers have been conducted by different organizations for the past five decades to ameliorate the challenges. The goal of this review was to summarize and document major research achievements recorded so far and recommend future research directions. As a result, mixing coffee pulp and husk in the composting pile with organic elements like farm yard manure and leguminous plants generates nutritionally high-quality compost in 45 days. In terms of increasing coffee yield, decomposed coffee husk (DCH) was found to be superior to <i>Sesbaniasesban</i> compost. Compost application rates of 5 to 10 tons ha^-1 (2 to 4 kg tree^-1 in dry weight base) and an equal proportion of soil incorporation and surface (50:50%) application techniques were found to be superior in increasing coffee yield. 50% recommended NP mineral fertilizer (RMF) (172 and 77 kg ha^-1 NP, respectively) + 50% recommended (DCH (10 ton ha^-1 or 4 kg tree^-1 on a dry weight basis), 50% RMF + 75% DCH, and <i>Desmodium</i>spp (green manure crop) + RMF (172 and 63 kg ha^-1 NP, respectively) significantly (<I>P</I>≤0.05) promote clean coffee yield at Agaro, Haru and Jimma, respectively. Forest soil or blends of top soils, compost and sand in 3:1:0 and 2:1:1 ratio, or organic manure and top soil mixture in 1:4, 2:4 and 3:4 ratios, produced strong and healthy coffee seedlings. A nursery pot amended with 750 mg P pot^-1 (2.5 kg soil) and 2.31 g lime + 250 mg P pot^-1 and 10 g lime + 800 mg P pot^-1 produced released pure line and hybrid seedlings, respectively, with superior dry matter yield at Jimma. Similarly, at Haru, an application of 4 g pot^-1 lime + 12.5 g pot^-1 DCH and 18.75 g pot^-1 DCH was a promising ameliorating management for acid soil for production of vigorous coffee seedlings for field planting. Future research should concentrate on evaluating other organic inputs and combined reclamation of lime-mineral fertilizer-compost, frequency of application, economic benefits, and long-term effects on soil physicochemical properties, coffee yield and bean quality, and establish cost effective soil fertility management in coffee-growing areas of the country. Furthermore, timely revision and calibration of mineral fertilizer recommendations made in the past with newly released coffee genotypes has become critical.

Effect of Different Media on Germination and Seedlings Performance of Chili Pepper (Capsicum annum)

The production of vegetable seedlings is an important business for some farmers in most parts of the world with poor media being a major constraint. An experiment was conducted to investigate the effect of different media on germination and nursery performance of chili pepper at the Department of Horticulture, Kwame Nkrumah University of science and Technology (KNUST). A Randomized Complete Block design with six treatments and three replications was used in the study. Media treatments were used either alone or in combination and they were: topsoil only, rice hull ash only, rabbit waste only, topsoil and rice hull ash (1:1), topsoil and rabbit waste (1:1) and topsoil and river sand (1:1). There were significant differences in germination percentage, seedling height, number of leaves and stem girth as function of the media treatments. The different media however did not affect days to 50% germination significantly. Comparatively, the highest and the lowest germination percentages (77.50% and 62.00%) were obtained by nursing seeds in the mixture of topsoil and rice hull ash as well as rabbit waste only respectively. In terms of growth characteristics, plant height and number of leaves were highest in seedlings nursed in topsoil and rice hull ash mixture (18.36 cm and 13.23 cm) respectively at the end of the study period. The highest stem girth was seedlings nursed in topsoil (3.129 mm) at the end of the experiment. Plants nursed in rabbit waste only had the lowest growth performance in terms of plant height (2.75 cm), number of leaves (4.50) and stem girth (1.27 mm) at the end of the experiment. Growth medium consisting of a mixture of proportion of topsoil and rice hull ash is therefore recommended for growing chili pepper seedlings since this combination improved both germination and subsequent growth as compared to the other media used in the experiment. Rice hull ash is not recommended to be used alone in raising chili pepper seedlings since it has a high pH which decreases seedling growth. Partially decomposed rabbit waste is also not suitable to be used as nursery medium because it retards seedling growth.