Plant Productivity Research Articles

Analysis of Sunflower and Oilseed Rape Competitiveness in the Conditions of Slovakia and Czech Republic

Abstract The paper primarily deals with the development of agriculture in the Slovak Republic and Czech Republic, analyzes the agricultural sector in the period 2012–2022 and examines in more detail agriculture, its plant production, especially oilseeds. Attention is given to brief information on the development and situation of the sunflower and oilseed rape, where we focus on the analysis of the development of selected indicators during the observed period, such as production, area sown, yields. Within our research we deal with the concept of competitiveness, using the appropriate indicators. Based on the data, via analysis we quantified the value of Revealed Comparative Advantage index (RCA) and Competitiveness Growth Index (RCA 1). The development of society and the opening of borders between individual states caused the development of foreign trade. Membership in the European Union meant for Slovak and Czech foreign trade the relinquishment of sovereignty in this areas and the adoption of a common trade policy that establishes rules for foreign trade within member countries, but also towards third countries. At the same time, however, Slovak Republic and Czech Republic gained access to the single internal market, which is of significant importance for foreign trade of countries.

Aggregate productivity, economic fluctuations, and export orientation: Evidence from India

Understanding the cyclicality in aggregate productivity helps answer whether the economy allocates resources efficiently or not. The paper analyses the sources of aggregate productivity growth, such as direct efficiency gain within-plants, allocative efficiency gain, and gains due to entry and exit during economic fluctuations. In particular, we exploit the economic shock of the Great Recession to analyse the validity of the 'Cleansing’ or ‘Scarring’ effect of recession and 'Schumpeterian Darwinian Selection' for Indian manufacturing. The rise and fall of within-plant and net-entry effects during the economic fluctuations explains the pro-cyclicality of productivity growth. Plants in export-oriented industries are crucial in explaining the pro-cyclicality. Negative external shock to exporting sectors during 2008–09 shifted resources from more productive to less productive plants. The relatively productive exporters exited the markets following the global crisis, scarring the economy. Nonetheless, the positive effect from the net-entry exit of plants during the economic downturn makes the 'Schumpeterian approach of Darwinian Selection' valid.

An integrated agroforestry-bioenergy system for enhanced energy and food security in rural sub-Saharan Africa.

Most people in rural sub-Saharan Africa lack access to electricity and rely on traditional, inefficient, and polluting cooking solutions that have adverse impacts on both human health and the environment. Here, we propose a novel integrated agroforestry-bioenergy system that combines sustainable biomass production in sequential agroforestry systems with biomass-based cleaner cooking solutions and rural electricity production in small-scale combined heat and power plants and estimate the biophysical system outcomes. Despite conservative assumptions, we demonstrate that on-farm biomass production can cover the household's fuelwood demand for cooking and still generate a surplus of woody biomass for electricity production via gasification. Agroforestry and biochar soil amendments should increase agricultural productivity and food security. In addition to enhanced energy security, the proposed system should also contribute to improving cooking conditions and health, enhancing soil fertility and food security, climate change mitigation, gender equality, and rural poverty reduction.

Air quality challenges in Central Asian urban areas: a PM2.5 source apportionment analysis in Dushanbe, Tajikistan.

This work presents the first comprehensive assessment of PM pollution sources in Dushanbe, Tajikistan. A total of 138 PM2.5 samples were collected during 2015-2016 and 2018-2019 and were analyzed through gravimetric, ED-XRF, and multi-wavelength absorption techniques. The results show that PM2.5 concentrations were substantially higher than the European annual limit value and WHO Air Quality Guidelines annual average value, with an average of 90.9 ± 68.5μgm-3. The PMF application identified eight sources of pollution that influenced PM2.5 concentration levels in the area. Coal burning (21.3%) and biomass burning (22.3%) were the dominant sources during the winter, while vehicular traffic (7.7%) contributed more during the warm season. Power plant emissions (17.5%) showed enhanced contributions during the warm months, likely due to high energy demand. Cement industry emissions (6.9%) exhibited significant contribution during the cold period of 2018-2019, while soil dust (11.3%) and secondary sulphates (11.5%) displayed increased contribution during the warm and cold months, respectively. Finally, waste burning (1.5%) displayed the lowest contribution, with no significant temporal variation. Our results highlight the significant impact of anthropogenic activities, and especially the use of coal burning for energy production (both in power plants and for residential heating), and the significant contribution of biomass burning during both warm and cold seasons.

No synergy between P and AMF inoculation to improve Sun Protection Factor production in Anadenanthera colubrina (Vell.) Brenan leaves

Secondary metabolite production in medicinal plants and other plants is improved by arbuscular mycorrhizae, plant stress, as well as nutritional factors. The compounds responsible for Sun Protection Factor from Anadenanthera colubrina (Vell.) such as flavonoids and proanthocyanidins may also increase by manipulation of plant stress or nutrient status, and inoculation with arbuscular mycorrhizal fungi (AMF). However, specific gaps regarding the viability of this agricultural tool need clarification, especially regarding the role of Phosphorus (P), one of the mycorrhizal symbiosis regulators and widely employed in plant cultivation. Therefore, this study aimed to understand the role of P in regulating SPF in Anadenanthera colubrina when cultivated in association with arbuscular mycorrhizal fungi (AMF). To this end, two concentrations of P2O5 (8 mg dm−3 and 50 mg dm−3) were evaluated, and two inoculation treatments were tested: control and seedlings inoculated with AMF inoculant. After 150 days in a greenhouse, the leaves were collected to obtain the ethanolic extracts and used to assess the SPF, production of flavonols, proanthocyanidins, saponins, pigments, and in vitro antioxidant activity. The presence of higher P levels in the soil (50 mg dm−3) renders mycorrhizal inoculation dispensable for the enhancement of SPF, production of photoprotective compounds, and antioxidant activity as plants grown under this condition showed a six-fold increase compared to non-inoculated seedlings kept in soil with a lower P level. On the other hand, leaves of A. colubrina seedlings inoculated with AMF and cultivated in soil supplemented with 8 mg P dm−3 displayed a SPF with a 4.9-fold increase and the biosynthesis of photoprotective and antioxidant compounds enhanced by more than five-fold compared to those not inoculated. Despite these benefits, these cultivation practices did not increase the accumulation of carotenoids and chlorophylls. Mycorrhizal inoculation and phosphate fertilization are agricultural practices that, independently, contribute to the increased SPF, biosynthesis of secondary metabolites, and antioxidant activity in A. colubrina leaves.

Climate change may shift metapopulations towards unstable source-sink dynamics in a fire-killed, serotinous shrub.

Climate change, with warming and drying weather conditions, is reducing the growth, seed production, and survival of fire-adapted plants in fire-prone regions such as Mediterranean-type ecosystems. These effects of climate change on local plant demographics have recently been shown to reduce the persistence time of local populations of the fire-killed shrub Banksia hookeriana dramatically. In principle, extinctions of local populations may be partly compensated by recolonization events through long-distance dispersal mechanisms of seeds, such as post-fire wind and bird-mediated dispersal, facilitating persistence in spatially structured metapopulations. However, to what degree and under which assumptions metapopulation dynamics might compensate for the drastically increased local extinction risk remains to be explored. Given the long timespans involved and the complexity of interwoven local and regional processes, mechanistic, process-based models are one of the most suitable approaches to systematically explore the potential role of metapopulation dynamics and its underlying ecological assumptions for fire-prone ecosystems. Here we extend a recent mechanistic, process-based, spatially implicit population model for the well-studied fire-killed and serotinous shrub species B. hookeriana to a spatially explicit metapopulation model. We systematically tested the effects of different ecological processes and assumptions on metapopulation dynamics under past (1988-2002) and current (2003-2017) climatic conditions, including (i) effects of different spatio-temporal fires, (ii) effects of (likely) reduced intraspecific plant competition under current conditions and (iii) effects of variation in plant performance among and within patches. In general, metapopulation dynamics had the potential to increase the overall regional persistence of B. hookeriana. However, increased population persistence only occurred under specific optimistic assumptions. In both climate scenarios, the highest persistence occurred with larger fires and intermediate to long inter-fire intervals. The assumption of lower intraspecific plant competition caused by lower densities under current conditions alone was not sufficient to increase persistence significantly. To achieve long-term persistence (defined as >400 years) it was necessary to additionally consider empirically observed variation in plant performance among and within patches, that is, improved habitat quality in some large habitat patches (≥7) that could function as source patches and a higher survival rate and seed production for a subset of plants, specifically the top 25% of flower producers based on current climate conditions monitoring data. Our model results demonstrate that the impacts of ongoing climate change on plant demographics are so severe that even under optimistic assumptions, the existing metapopulation dynamics shift to an unstable source-sink dynamic state. Based on our findings, we recommend increased research efforts to understand the consequences of intraspecific trait variation on plant demographics, emphasizing the variation of individual traits both among and within populations. From a conservation perspective, we encourage fire and land managers to revise their prescribed fire plans, which are typically short interval, small fires, as they conflict with the ecologically appropriate spatio-temporal fire regime for B. hookeriana, and likely as well for many other fire-killed species.

Effect of planting dates and some growth stimulants on growth and productivity of chia plant

Effect of planting dates and some growth stimulants on growth and productivity of chia plant

Improving productivity of arabica coffee genotype G1 through potassium fertilization

Abstract One of the determinants of coffee productivity is the availability of nutrients in the soil, with potassium being among the essential nutrients required to enhance productivity. Therefore, this study aimed to determine the optimal potassium fertilizer dosage needed to increase the productivity of Arabica coffee plants of the G1 genotype. This study was conducted in the experimental garden of Syiah Kuala University in Bener Meriah Regency, Aceh Province, Indonesia using a Non-Factorial Randomized Block Design (RBD). A total of 132 Arabica coffee trees of genotype G1 were randomly selected based on specific criteria, such as 8 years of age, planted with a spacing of 2.5 x 2.5 m, pruned properly, grown under moderately dense shade of Leucaena trees, and well-maintained. The treatments included a control group without potassium fertilizer and multiple groups receiving potassium fertilizers at 29, 58, 87, 116, and 145 kg K2O per hectare. These potassium sources were derived from potassium chloride (KCl) fertilizer containing 58% K2O and Rice Husk Ash containing 2% K2O, respectively. This resulted in 11 treatment units, each comprising 3 coffee trees replicated 4 times, for a total of 44 treatment units. The results showed that potassium fertilization from KCl and Rice Husk Ash had a significant effect on the increased productivity of Arabica coffee genotype G1. The effect was observed based on the number of productive branches per tree, clusters per branch, fruits per cluster, fruits per tree, the weight of red cherries per tree, parchment coffee per tree, green beans per tree, and the green beans yield at 14% moisture content. The optimal potassium fertilizer dosage was 145 kg K2O per hectare, equivalent to 250 kg KCl or 156.25 g KCl per tree. Additionally, it was observed that potassium sourced from KCl was more effective than potassium from Rice Husk Ash due to the longer time the latter takes to improve the productivity of Arabica coffee.

Combining solar panels with plants for sustainable energy and food production: state of the art

The need for alternative energy sources becomes extensive because of the escalating cost of fossil fuels. The goal of this paper is to examine the effectiveness of combining photovoltaics and agriculture for better yield. Photovoltaic (PV) solar plants will compete with farms for available land. In this study, the methodologies are discussed how it is possible to maximize land utilization by placing solar arrays and food crops on the same plot of land. The term is proposed "agrivoltaic system" to describe this setup. Conventional solutions (discrimination of agricultural and energy extracting) were compared to two agrivoltaic schemes with varying density of PV arrays using land equivalent ratios. We utilized a crop model to simulate the amount of sunlight reaching the crop from an array of solar panels and to speculate on the yield reduction that would result from the partial shading. These early findings suggest that agrivoltaic systems may be highly effective; the two densities of PV panels were anticipated to boost worldwide land production by 73%. One possible explanation for the success of these hybrid systems is the presence of facilitation mechanisms analogous to those seen in agroforestry. At the end it is suggested that in places where arable land is rare, new solar plants may find it beneficial to produce both power and food.

Impact of Humic Substances on Alleviation of Soil Salinity and the Enhancement of Plant Productivity: a review

Humic substances (HS) are a major component of organic matter in soil, and they have long been recognized for their ability to promote plant growth in a sustainable manner. Recently, there has been a lot of effort put into using multiple approaches to study the connection between the chemical structure of HS compounds and their effect on plant biological processes. Positive physiological responses at the local and systemic levels have been linked to the presence of specific functional groups in HS. Hormone-like signaling pathways are responsible for eliciting these reactions. This review was written with one goal in mind: to help readers gain a firm grasp on the research surrounding the application of HSs. The spatial arrangement of hydrophilic and hydrophobic regions, as well as the dosage, source, molecular size, degree of hydrophobicity, and aromaticity, all contribute significantly to HS's biological efficacy. Therefore, our hypothesis explains the beneficial effect of HS in salt-affected rhizospheres, likely attributed to both direct and indirect influences on plant metabolism, soil microorganism metabolism, soil nutrient uptake dynamics, and soil physical conditions. Keywords: Humic substance, germination, salinity, plant growth

The Antioxidant Defense System of Tomato (Solanum lycopersicumL.) Varieties under Drought Stress and upon Post-Drought Rewatering.

Water shortage induces physiological, biochemical, and molecular alterations in plant leaves that play an essential role in plant adaptive response. The effects of drought and post-drought rewatering on the activity of antioxidant enzymes and levels of H2O2, phenolic compounds, ascorbic acid, and proline were studied in six local tomato (Solanum lycopersicumL.) varieties. The contents of H2O2 and ascorbic acid increased in all drought-exposed tomato plants and then decreased upon rewatering. The level of phenolic compounds also decreased in response to water shortage and then recovered upon rehydration, although the extent of this response was different in different varieties. The activities of ascorbate peroxidase (APX) and guaiacol peroxidase (POX) and the content of proline significantly increased in the drought-stressed plants and then decreased when the plants were rewatered. The activities of 8 constitutive APX isoforms and 2 constitutive POX isoforms varied upon exposure to drought and were observed after rewatering in all studied varieties. The information on the response of tomato plants to drought and subsequent rewatering is of great importance for screening and selection of drought-tolerant varieties, as well as for development of strategies for increasing plant productivity under adverse environmental conditions.

AcEXPA1, an α-expansin gene, participates in the aluminum tolerance of carpetgrass (Axonopus compressus) through root growth regulation.

AcEXPA1, an aluminum (Al)-inducible expansin gene, is demonstrated to be involved in carpetgrass (Axonopus compressus) root elongation under Al toxicity through analyzing composite carpetgrass plants overexpressing AcEXPA1. Aluminum (Al) toxicity is a major mineral toxicity that limits plant productivity in acidic soils by inhibiting root growth. Carpetgrass (Axonopus compressus), a dominant warm-season turfgrass widely grown in acidic tropical soils, exhibits superior adaptability to Al toxicity. However, the mechanisms underlying its Al tolerance are largely unclear, and knowledge of the functional genes involved in Al detoxification in this turfgrass is limited. In this study, phenotypic variation in Al tolerance, as indicated by relative root elongation, was observed among seventeen carpetgrass genotypes. Al-responsive genes related to cell wall modification were identified in the roots of the Al-tolerant genotype 'A58' via transcriptome analysis. Among them, a gene encoding α-expansin was cloned and designated AcEXPA1 for functional characterization. Observed Al dose effects and temporal responses revealed that Al induced AcEXPA1 expression in carpetgrass roots. Subsequently, an efficient and convenient Agrobacterium rhizogenes-mediated transformation method was established to generate composite carpetgrass plants with transgenic hairy roots for investigating AcEXPA1 involvement in carpetgrass root growth under Al toxicity. AcEXPA1 was successfully overexpressed in the transgenic hairy roots, and AcEXPA1 overexpression enhanced Al tolerance in composite carpetgrass plants through a decrease in Al-induced root growth inhibition. Taken together, these findings suggest that AcEXPA1 contributes to Al tolerance in carpetgrass via root growth regulation.

Selected Beneficial Microbes Alleviate Salinity Stress in Hydroponic Lettuce and Pak Choi

Hydroponics is widely used in greenhouse and vertical farming production because these facilities can precisely control environmental conditions such as lighting, temperature, and vapor pressure deficit. However, the fertilizer solutions have a short life span, and they often do not have adequate microbial populations to enhance plant growth. Previous studies have shown the potential of beneficial microbes to promote plant production and alleviate abiotic and biotic stressors in the field, and studies on their use in controlled environments such as greenhouses and vertical farms are limited in the literature. In this study, we selected several plant growth promoting microbes (PGPMs) and tested their effects on alleviating salinity stress in ‘Rex’ lettuce (Lactuca sativa) and ‘Red Pac’ pak choi (Brassica chinensis) grown in deep water culture hydroponics. Our goal was to use one stressor, salinity, that induces profound symptoms in plant morphology. A three-cycle study was conducted using five PGPMs [Bacillus, Glomus, Lactobacillus, Trichoderma, and Bacillus/Pseudomonas/Trichoderma (B/P/T) mix] and two salinity levels [no salinity and salinity treatment, with 120 mM, 40 mM, and 80 mM sodium chloride (NaCl) solution used for the first, second, and third cycles, respectively]. We measured the effects of PGPMs and salinity on plant growth and quality and the solution pH and electrical conductivity (EC). Salinity stress decreased lettuce and pak choi leaf area and shoot fresh weight and increased plant leaf chlorophyll and anthocyanin contents with increased solution EC. Under high-salinity stress (120 mM NaCl), the addition of Trichoderma reduced pak choi leaf area and fresh weight but increased solution pH, whereas under low salinity stress (40 mM NaCl), Trichoderma increased pak choi leaf chlorophyll content. Under moderate-salinity stress (80 mM NaCl) condition, the addition of Glomus sp. increased lettuce fresh weight and leaf area, and B/P/T mix increased pak choi leaf area. In conclusion, using the selected PGPMs in low to moderate-salinity stress could increase lettuce and pak choi growth and quality parameters. These results have some practical applications in the future when more saline water is used for production.

Теоретические основы оценки аэродинамического воздействия ветровых потоков на сооружения завода по подготовке и сжижению природного газа

Leaks (spills) of liquefied gases evaporate rapidly on the ground (water) and initially generate a cold plume of heavy vapors. The plume spreads fast downwind, heats up with time, and can become positively volatile in case the concentration of interest for the study (above the lower flammability limit) is reached; therefore, the plume can rise and transform into a vapor cloud. The plume or the vapor cloud can ignite in the flash form. Such situations are possible at liquefied natural gas production plants or regasification units where large amounts of explosive substances are handled involving changes in their aggregate state. The article analyses the significance of the wind impact on the facilities of natural gas liquefaction plants for regular operation and the potential consequences of emergencies. In order to assess the wind impact, the direct numerical modeling of the structure of local wind flows generated at the airflow around the plant facilities by vertical method is suggested. An example of numerical modeling for a natural gas liquefaction plant based on the modular constructions of the process line is provided.

Rational Design for the Complete Synthesis of Stevioside in Saccharomyces cerevisiae.

Stevioside is a secondary metabolite of diterpenoid glycoside production in plants. It has been used as a natural sweetener in various foods because of its high sweetness and low-calorie content. In this study, we constructed a Saccharomyces cerevisiae strain for the complete synthesis of stevioside using a metabolic engineering strategy. Firstly, the synthesis pathway of steviol was modularly constructed in S. cerevisiae BY4742, and the precursor pathway was strengthened. The yield of steviol was used as an indicator to investigate the expression effect of different sources of diterpene synthases under different combinations, and the strains with further improved steviol yield were screened. Secondly, glycosyltransferases were heterologously expressed in this strain to produce stevioside, the sequence of glycosyltransferase expression was optimized, and the uridine diphosphate-glucose (UDP-Glc) supply was enhanced. Finally, the results showed that the strain SST-302III-ST2 produced 164.89 mg/L of stevioside in a shake flask experiment, and the yield of stevioside reached 1104.49 mg/L in an experiment employing a 10 L bioreactor with batch feeding, which was the highest yield reported. We constructed strains with a high production of stevioside, thus laying the foundation for the production of other classes of steviol glycosides and holding good prospects for application and promotion.

Increasing Growth, Production and Nutrient Uptake of Pakcoy (Brassica rapa L) Plant on Peat Soil by Applying Polyvalent Cation Ameliorant Cu2+, Fe3+, Zn2+ and Palm Front Compost

The development in Riau has led to converting agricultural land to non-agricultural use, impacting the cultivation of vegetable crops on peatlands that require intensive treatment to achieve maximum productivity. The research aims to assess the effects of ameliorants and oil palm frond compost application on the growth, production, and nutrient uptake of pakcoy plants (Brassica rapa L). The experiment utilized a Completely Randomized Factorial Design with 2 factors. The first factor involved ameliorants with 4 treatment levels: without ameliorant, Cu2+, Fe3+, and Zn2+. The second factor included oil palm frond compost with 4 treatment levels: without compost, 12. 24. and 36 g/plant. Parameters observed were plant height, leaf count, fresh weight, dry weight, and nutrient uptake of N, P, and K. Results showed significant interaction effects between ameliorants and oil palm frond compost on plant height, leaf count, fresh weight, and nutrient uptake of N, P, and K, with the best treatment being Cu2+ ameliorant and 24 g/plant oil palm frond compost. The primary effect of ameliorants significantly influenced all observed parameters, with Cu2+ being the best treatment. The primary effect of oil palm frond compost significantly influenced all observed parameters, with 12 g/plant being the best treatment.

Methylosinus trichosporium OB3b bioaugmentation unleashes polyhydroxybutyrate-accumulating potential in waste-activated sludge

BackgroundWastewater treatment plants contribute approximately 6% of anthropogenic methane emissions. Methanotrophs, capable of converting methane into polyhydroxybutyrate (PHB), offer a promising solution for utilizing methane as a carbon source, using activated sludge as a seed culture for PHB production. However, maintaining and enriching PHB-accumulating methanotrophic communities poses challenges.ResultsThis study investigated the potential of Methylosinus trichosporium OB3b to bioaugment PHB-accumulating methanotrophic consortium within activated sludge to enhance PHB production. Waste-activated sludges with varying ratios of M. trichosporium OB3b (1:0, 1:1, 1:4, and 0:1) were cultivated. The results revealed substantial growth and methane consumption in waste-activated sludge with M. trichosporium OB3b-amended cultures, particularly in a 1:1 ratio. Enhanced PHB accumulation, reaching 37.1% in the same ratio culture, indicates the dominance of Type II methanotrophs. Quantification of methanotrophs by digital polymerase chain reaction showed gradual increases in Type II methanotrophs, correlating with increased PHB production. However, while initial bioaugmentation of M. trichosporium OB3b was observed, its presence decreased in subsequent cycles, indicating the dominance of other Type II methanotrophs. Microbial community analysis highlighted the successful enrichment of Type II methanotrophs-dominated cultures due to the addition of M. trichosporium OB3b, outcompeting Type I methanotrophs. Methylocystis and Methylophilus spp. were the most abundant in M. trichosporium OB3b-amended cultures.ConclusionsBioaugmentation strategies, leveraging M. trichosporium OB3b could significantly enhance PHB production and foster the enrichment of PHB-accumulating methanotrophs in activated sludge. These findings contribute to integrating PHB production in wastewater treatment plants, providing a sustainable solution for resource recovery.Graphical abstract

Multiomics and biotechnologies for understanding and influencing cadmium accumulation and stress response in plants.

Cadmium (Cd) is one of the most toxic heavy metals faced by plants and, additionally, via the food chain, threatens human health. It is principally dispersed through agro-ecosystems via anthropogenic activities and geogenic sources. Given its high mobility and persistence, Cd, although not required, can be readily assimilated by plants thereby posing a threat to plant growth and productivity as well as animal and human health. Thus, breeding crop plants in which the edible parts contain low to zero Cd as safe food stuffs and harvesting shoots of high Cd-containing plants as a route for decontaminating soils are vital strategies to cope with this problem. Recently, multiomics approaches have been employed to considerably enhance our understanding of the mechanisms underlying (i) Cd toxicity, (ii) Cd accumulation, (iii) Cd detoxification and (iv) Cd acquisition tolerance in plants. This information can be deployed in the development of the biotechnological tools for developing plants with modulated Cd tolerance and detoxification to safeguard cellular and genetic integrity as well as to minimize food chain contamination. The aim of this review is to provide a current update about the mechanisms involved in Cd uptake by plants and the recent developments in the area of multiomics approach in terms of Cd stress responses, as well as in the development of Cd tolerant and low Cd accumulating crops.

Productivity Of Palm Oil (Elaeis guineensis Jacq) (Elaeis guineensis Jacq) In The Highlands In Simalungun District With Percentage Levels Of Bunch Rot Based On Planting Year

The study was conducted to evaluate the percentage rate of bunch rot by planting year and the productivity of oil palm in the highlands. The research was conducted on the plant area yielded by survey method at Kebun Bah Birung Ulu Sidamanik Subdistrict Simalungun Regency. The study was conducted in August 2014 with a height of 648 - 1087 meters above sea level located on Longitude: 2o 52 '08.70' 'N - 99o 00' 14.96'' T and Latitude: 2o 46 '12.59' 'U-98o 56 ' 03.63 '' Q. This research was conducted by collecting data such as An Overview of Biru Ulu Garden of PTPN. IV, the production of fresh fruit bunches per block per year of planting: Actual production (tons/ha) for the 1996, 2004, 2005 and 2006 cropping periods and the number of staples per five years was also used in the determination of palm oil grade and attack percentage data bunch rot) and fruit parthenocarpy in Garden Bah Birung Ulu, PT Perkebunan Nusantara IV, Sidamanik Subdistrict, Simalungun Regency, North Sumatra Province. Research Results Show Oil palms at 4 - 9 years old are still attacked by rotting fruit, but the percentage of attacks tends to decrease with the age of oil palm plantations. The percentage of fruits shipped to the palm oil mill at 4 - 5 year olds is very low and tends to increase fruit rot and parthenocarpi attacks with increasing altitude of the plant site. bunch diseases commonly caused by Marasmius palmivorus also affect the low productivity of plants in the highlands

EFEKTIVITAS TIGA BAHAN ORGANIK TERHADAP SERANGAN HAMA, PERTUMBUHAN DAN PRODUKSI SAWI

Pakcoy mustard greens are a type of rain-resistant vegetable. Pakcoy has green leaves with high nutritional content and economic value. One of the efforts that can be made to increase plant production is by providing fertilizer. Fertilization is carried out in order to meet the nutrient needs of plants, so that they can provide high yields, especially using organic fertilizer so that you can use waste as fertilizer. One type of recycled waste that can be used as organic fertilizer is egg shells, tea dregs and banana peels, each of which contains elements that are good for cultivation. Apart from that, pak choy mustard plants have the main problem that causes damage to pak choy, namely destructive pests that eat pak choy leaves such as plutella caterpillars, tritip caterpillars, armyworms, aphids (Aphids), cabbage spanner caterpillars. This research will be carried out from October to December 2023 at the UNISKA Integrated Field Laboratory. With a height of 67 meters above sea level, the temperature is 31.2◦C, humidity is 62.3% and soil pH is 6. Based on the research results, it shows that there is a very real influ.ence on the observed variables of plant height and number of leaves at the age of 14, 21 and 28 DAP, and it has an effect significant in root length at 28 days after planting. Fresh weight, dry weight, and armyworm pest attacks were lowest at P7.