bluuebunny/crossref_metadata_2025 huggingface dataset:
Analysis of aging effect on lower limb muscle activity using short time Fourier transform and wavelet decomposition of electromyography signal
Authors: Khan Tawhidul Islam , Moznuzzaman Md. , Ide Shuya
Published: May 2023

The ubiquity of human knee osteoarthritis (OA) has increased among the elderly people worldwide. In this paper, the intended focus has been given to evaluate the consequence of aging on the lower limb (LL) muscle activities during sit-stand-sit perturbations. Eighty-four participants, including 51 eligible healthy subjects and 33 knee OA patients, took part in this study. The activity of the vastus lateralis, vastus medialis, rectus femoris, and the medial head of gastrocnemius muscles were evaluated using the surface electromyography (EMG) technology. Aging effects on the LL muscles were statistically analyzed by extracting the EMG features based on the conventional technique, short time Fourier transform (STFT) and Wavelet Transform (WT). Healthy subjects were categorized into three groups based on age. The Jarque–Bera test was performed for checking the normality of the dependent variables. To clarify the impact of aging statistically on muscle activity, the independent t-test was performed. The muscle activities of middle age and older age participants were identified to be considerably higher than those of young people. However, they were lower than those of the OA patients. Both the STFT and the WT performed as useful and powerful tools for analyzing EMG signals compared to the conventional filtering approach. The WT outperformed the STFT notably in statistical quantification of the aging effects on LL muscle activities.
Atomization of liquid pulsed jet in subsonic crossflow
Authors: Chang Jianlong , He Liujing , Chen Lianhua , Li Zhaoyong
Published: May 2023

Pulsed jet is an effective solution to improve fuel jet penetration depth and consequently increase the mixing efficiency of gas–liquid in conventional combustion chambers. This has the benefits of reducing pollutant emissions and diminishing the instability of fuel combustion. However, the atomization process of pulsed jets with small amplitude has still not been properly investigated. This paper studies such a process through Large Eddy Simulation and a Coupled Level Set and Volume of Fluid method. We investigate the atomization process in a liquid pulsed jet with a subsonic crossflow and the impact of the Strouhal number on atomization morphology and the behavior of the pulsed jet in general. Results show that, with a constant mass flow rate, the role of Rayleigh–Taylor instability is replaced by the periodic fluctuation of the jet velocity, which ends up dominating the primary process of atomization of the liquid transverse pulsed jet. This also improves atomization, in general, and the fragmentation of the jet. We also show that the Strouhal number significantly impacts the penetration depth of the jet, with high values increasing penetration by up to 12%.
Research on the damage diagnosis model verification method of cable-stayed bridges
Authors: Liu Jie , Chen Jiameng , Liu Qingkuan , Wang Hailong , Bu Jianqing
Published: May 2023

To solve the problem that the damage diagnosis model of cable-stayed bridges cannot quantitatively evaluate its validity, the verification method of the diagnosis model is investigated. A model validation method [Root-Mean-Square Error (RMSE)-Statistical Hypothesis Test (SHT), R–S] that combines the RMSE evaluation index and the SHT is proposed and applied to the reliability evaluation of the cable-stayed bridge data mining damage diagnosis model. First, the R–S method evaluates the diagnostic effect of the model via the evaluation index. Second, the SHT method is used to quantitatively compare the consistency between the output data of the diagnostic model and the actual structure output data. Finally, the validity of the model is quantitatively evaluated. The application process of the proposed method is demonstrated by an example. The results show that the diagnostic model has strong reliability and that the confidence level Pδ exceeds 90%, which indicates the effectiveness of the diagnostic model verification method.
Candida biofilm formation and recurrent vulvovaginal candidiasis
Authors: Sun Yao , Kostoulias Xenia , Qu Yue
Published: May 2023

Recurrent vulvovaginal candidiasis (RVVC), a recalcitrant Candida infection of the lower female reproductive tract, is a difficult-to-treat medical condition affecting the morbidity of many otherwise healthy women. Cumulative experimental evidence supports the involvement of biofilm formation of Candida in the pathogenesis of RVVC and its treatment failure. In this review, we will discuss important insights into the roles of Candida biofilms in RVVC.
Mineralogical control on physically protected soil organic matter in a neotropical moist forest
Authors: Huber Molly E. , Yavitt Joseph B. , Wright S. Joseph
Published: May 2023

Context Minerals and organic matter physically associate in many soils, yet the precise nature, either via a hierarchy of aggregate particles or by build-up of organo–mineral associations, remains obscure, especially in tropical forest environments. Aims We investigated physically protected organic matter by comparing soils with contrasting parent material, topography, and pedogenesis, but with similar tropical moist forest on Barro Colorado Island in the lowlands of Panama. Methods Bulk soil from 10 sites was separated by size into free-floating particles, macroaggregates (>250 μm), microaggregates (53–250 μm), and <53-μm particles. A subsample of macroaggregates was disintegrated and separated into coarse particles (>250 μm), occluded microaggregates, and occluded <53-μm particles. Concentrations and natural abundance of stable isotopes for carbon (C) and nitrogen (N) were determined for each fraction, and ratios (C:N, stable isotopes) were used to characterise organic matter for each fraction. Key results Macroaggregates were the largest fraction of bulk soil (71%) and were 15% greater in kaolinite- than smectite-dominated soils. Macroaggregates were composed of coarse particles (14%), occluded microaggregates (62%), and occluded <53-μm particles (24%). Concentrations of C and N widely varied among fractions but the variation was not related to clay mineralogy. The C:N ratio and stable N isotope ratio indicated more decomposed organic matter in kaolinite- than smectite-dominated soils. Conclusions and implications Macroaggregates composed of plant detritus and microaggregates in the Barro Colorado Island soils imply that the aggregate hierarchy route ultimately protects soil organic matter in this tropical forest environment.
Body size predicts the rate of contemporary morphological change in birds
Authors: Zimova Marketa , Weeks Brian C. , Willard David E. , Giery Sean T. , Jirinec Vitek , Burner Ryan C. , Winger Benjamin M.
Published: May 2023

Variation in evolutionary rates among species is a defining characteristic of the tree of life and may be an important predictor of species’ capacities to adapt to rapid environmental change. It is broadly assumed that generation length is an important determinant of microevolutionary rates, and body size is often used as a proxy for generation length. However, body size has myriad biological correlates that could affect evolutionary rates independently from generation length. We leverage two large, independently collected datasets on recent morphological change in birds (52 migratory species breeding in North America and 77 South American resident species) to test how body size and generation length are related to the rates of contemporary morphological change. Both datasets show that birds have declined in body size and increased in wing length over the past 40 y. We found, in both systems, a consistent pattern wherein smaller species declined proportionally faster in body size and increased proportionally faster in wing length. By contrast, generation length explained less variation in evolutionary rates than did body size. Although the mechanisms warrant further investigation, our study demonstrates that body size is an important predictor of contemporary variation in morphological rates of change. Given the correlations between body size and a breadth of morphological, physiological, and ecological traits predicted to mediate phenotypic responses to environmental change, the relationship between body size and rates of phenotypic change should be considered when testing hypotheses about variation in adaptive responses to climate change.
Assessment of spatial acuity in typically developing children
Authors: Syeda Aisha , Nisha Kavassery Venkateswaran , Jain Chandni
Published: May 2023

Objective:

Two main techniques to assess auditory spatial acuity include real-source localisation in the sound-field and virtual-source localisation under headphones. The present study aimed to compare the efficacy of the two assessment paradigms (sound-field localisation and closed-field lateralisation) to measure the spatial abilities of normal-hearing school-aged children.

Methods:

Spatial acuity was assessed in twenty-seven normal-hearing children aged 7–13 years (Mage: 10.4; SD: 1.6) using two paradigms; 1) localisation test (a sound field paradigm) and 2) virtual auditory space identification test (VASI,a closed-field paradigm). The accuracy scores and error rates were calculated from confusion matrices for each participant in both paradigms.

Results:

The Wilcoxon sign rank test showed no statistically significant difference between the two tests in the error rates. However, there was a significant difference in the accuracy scores between the two paradigms for azimuths/locations: Right45°, Right135°, Left45°, and Left135°. Spearman correlation showed a mild to moderate positive correlation between all the measures of the two paradigms.

Conclusion:

The results show that VASI and sound-field localisation paradigms are comparable in assessing spatial acuity in children. A further experiment is warranted to establish its validity in the clinical population as a test for spatial acuity.
Cogon grass (Imperata cylindrica L.) mulch effect on microclimate, weed management and yield of upland rice
Authors: Hayati P K D , Abidah P A , Juniarti  , Syarif A
Published: May 2023

One of the problems of upland rice cultivation in dry land is the availability of water needed to maintain humidity and temperature around plant roots. Cogon grass (Imperata cylindrica L.) mulch which has a long decomposed duration, can be an alternative to maintain the microclimate humidity and control weeds. This study aimed to obtain the best dose of cogon grass mulch on microclimate, weed management and upland rice yield on ameliorated ultisol soils. The research was carried out using a randomized complete block design with five doses of cogon grass mulch, i.e. 0, 10, 15, 20, and 25 tons/ha and three replications. Data were analyzed statistically by the F test at a 5% significance level and mean comparison using Tukey’s test. Results showed that applying cogon grass mulch could reduce temperature and increase the soil’s moisture. Biomass and species of weeds decreased with increasing doses of cogon grass mulch. Applied 10 tons/ha of cogon grass mulch effectively suppresses weed growth by 42.8%. Cogon grass mulch application did not affect upland rice growth variables, but 20 t/ha mulch significantly increased the yield by 21.7%.
Salinity stress mitigation on Zea mays L. seedling by halotolerant bacteria
Authors: Saryanah N A , Sulastri  , Himawati S , Bidara I S , Roswanjaya Y P , Asiani N , Sukmadi R B , Irawati A F C
Published: May 2023

Halotolerant bacteria are reported as a potential biostimulant to mitigate saline stress on various crops. The mechanism of halotolerant bacteria in elevating plant growth under saline stress is associated with their plant growth-promoting (PGP) traits. This study evaluated the activity of single-strain halotolerant phosphate-solubilizing bacteria and its consortia with halotolerant bacteria that were able to fix nitrogen and produce ACC deaminase in alleviating salinity stress on Zea mays seedlings under in vitro conditions. One single strain and five consortia of bacterial isolates were tested for seedling growth assay under four salinity levels (0, 60, 80, and 100 mM). In vitro assay showed that halotolerant bacteria B1 (Vibrio alginolycticus) and all consortia significantly increased root number at 60 mM salinity level. Consortium B3 (V. alginolyticus+Salinicola zeshunii) was also able to improve the fresh weight of seedlings significantly (by 63.3%). Moreover, inoculation of consortium B3 affected more proline and soluble sugar accumulation in Z. mays seedlings when compared to uninoculated seedlings. We conclude that the application of a consortium of halotolerant bacteria V. alginolyticus+S. zeshunii was potentially used in improving Z. mays growth in slightly and moderately saline areas.
Potency of entomopathogen Beauveria bassiana fungus as biofertilizer and biostimulant to increase the plant growth of Cayenne pepper (Capsicum frutescens L.)
Authors: Yusniwati  , Nurbailis  , Trizelia  , Saragih M
Published: May 2023

This research aimed to determine the Beauveria bassiana entomopathogen fungus as a biofertilizer and biostimulant. The research was conducted at the Biological Control laboratory and Wire House, Universitas Andalas. The potency of B. bassiana produced the IAA hormone was carried out by a This was qualitative research by observing a pink color change in the Salkowsky solution while the potency of B. bassiana to dissolve phosphate by using Pikovskaya medium. The test results on Pikovskaya media showed that all tested isolates had the potential to dissolve phosphate at 7, 10, and 14 days. The largest clear zone area was in the 14 days, found in Bb WS isolates (5.42 mm) followed by TD312 isolates (5.28mm). To test of plant growth in the laboratory was carried out by testing the germination of seeds by blotter test and test on paper. The design used was a non-factorial Completely Randomized. The results showed that the highest percentage of germination was found in TD312 and BbWS isolates. The potency of B. bassiana isolates as growth promoters can be seen from an increase in plant height and the number of chili leaves. All of the results indicated that entomopathogen fungus can be applied as biological fertilizers and biostimulants on cayenne pepper plants.
The effect of callus induction media for somatic embryo formation in Hevea brasiliensis Muell. Arg
Authors: Royani J I , Khairiyah H , Mira F R , Karyanti  , Watanabe N
Published: May 2023

The method for micro-propagation of rubber (Hevea brasiliensis Muell. Arg) by somatic embryo has been conducted. The aim of the research will describe the effect of media used for callus induction on the somatic embryo formation of rubber plants. Embryonic callus had been induction in 3 media, i.e.; MH1, MH2, and MH3. After callus induction, all callus were induced in media for embryo somatic expression. Maturation of cotyledons was performed using liquid media with filter paper as a bridge to absorb the media. The results showed that the percentage of callus was induced differently for each media. MH3 media was the best media for callus induction with 62.5% of callus forms, but for embryonic callus, MH1 was the best media. Not all of the calluses could be expressed to become somatic embryos. Most calluses derived from MH1 media were the best callus for somatic embryos formed.
Characterization of Passiflora edulis accessions with sweet taste potential in Padang
Authors: Sutoyo  , Hayati P K D , Irawan M , Kuswandi  , Marta N
Published: May 2023

A sweet fruit taste of passion fruit is produced by Passiflora ligularis, which adapts in around 1400 masl. Some P. edulis accessions which wide elevation adaptation was reported to have a sweet fruit taste. This study aimed to examine the morphological characteristics of progenies from red- and yellow-rind passion fruit and obtain an adaptive sweet passion fruit accession in low-elevation conditions. A total of 118 progenies of P. edulis classified as their parents’ rind color and fruit shape were germinated in October 2021 and transplanted to the field after two months in Padang city at 163 masl elevations. The characterization was conducted by observing all accessions which produced ripe fruits until September 2022. Results from 35 accessions showed variation in quantitative characters, while similar qualitative characters in stem, leaf, and flower among accessions, except tendril and stem color. The noticeable differences between the accessions are fruit characteristics. Round red-rind accessions have the heaviest fruit (102.05g). Yellow-rind passion fruit has a sweetness level of 19.5°brix, sweeter than oval red-rind (17.04°brix) and round red-rind (16°brix). Accession KK 42, ML 44 and MB 26 reveal high TSS, i.e. 20, 19 and 18°brix, respectively; however, no accession has a sweet taste fruit. A recessive allele may control the sweet taste character. Segregation of the genes that control carbohydrate metabolism into sugar in fruits and outcrosses occurring among accessions are responsible for the variation in fruit characteristics.
Effect of pruning and application of KNO3 + MKP fertilizer on the generative development of several varieties of grapes (Vitis vinifera L.)
Authors: Ekawati F , Suliansyah I , Erona S M , Palja E O , Ibrahim M R
Published: May 2023

Research on grape cultivation is still rarely carried out in Indonesia (Tropical Countries) unless it is carried out by Research Centers, which are indeed engaged in developing grapes. This study aims to examine the effect of pruning and application of white Potassium Nitrate (KNO3) and Mono Potassium Phosphate (MKP) on the development of the generative phase of several grape varieties. The study used a completely randomized design (CRD) with two factors, namely varieties (V1: Taldun, V2: Akademik, and V3: Jupiter), and several combinations of fertilizers (P1: KNO3 1 g/L + MKP 3 g/L, P2: KNO3 2 g/L + MKP 5 g/L, and P3: KNO3 3 g/L + MKP 7 g/L). Observations were made on post-pruning bud sprouting time, percentage of buds that produced flowers, percentage of flowers turning into fruit, fruit size (diameter), and total soluble solids (°brix). The data revealed that pruning treatment followed by fertilizer application of KNO3 3 g/L + MKP 7 g/L accelerated the generative phase and produced better fruit quality and quantity for the Jupiter variety.
Effect of planting media modification on growth and seed potential of two vanilla varieties
Authors: Melati  , Meilawati N LW , Arlianti T
Published: May 2023

The discontinuous availability of good-quality seeds had become the main problem in vanilla development. One of the limiting factors is the retarded growth of tendrils, which are used as plant propagation materials. The growth of vanilla vines using recommended cultivation techniques only produces one internode/month. Therefore it is necessary to modify the cultivation techniques to accelerate vanilla seeds production. Modifying the seed propagation media is one of the possible adjustments. This research aims to analyze the effect of planting media modification on vanilla growth and seed potency. The study used a randomized block design of 2 factors with four replications. The first factor is variety, namely Vania 1 and Vania 2, while the second factor is the type of planting media, namely media 1 (compost: burnt husks: cow manure (1:1:1)), media 2 (soil: compost: burnt husks: cow manure (1:1:1:1) ), media 3 (recommended cultivation (soil: cow manure (1:1)). The parameters observed were plant growth (tendrils length, number of internodes, number of leaves, leaf length, leaf width), cutting potential (seeds) and chlorophyll content. The results showed that the growth of Vania 1 was the same as that of Vania 2 and media composition without soil (media 1) resulted in the highest cutting potential compared to other media.
Identification and morphological characterization of local red chilies from West Sumatra
Authors: Suliansyah I , Ekawati F , Hariandi D
Published: May 2023

West Sumatra still stocks local chilies, which, based on information, have good resistance to viruses. This study aims to characterize the morphology of several local red chilies in West Sumatra due to exploration. The characterization refers to general guidelines for compiling descriptions of vegetable (chili) varieties issued by the Ministry of Agriculture of the Republic of Indonesia in 2021. The qualitative data from the characterization results were processed using the NTsys Ver.2.02 program to see the kinship of several West Sumatra local red chili. In comparison, the quantitative data were analyzed with various values to determine the criteria for diversity. Based on the results of grouping phylogenetic trees, at a similarity coefficient of 59%, two groups were obtained, namely, the first group consisting of Chilli Kawek Solok Selatan and Chilli Kampung Solok Selatan and the second group consisting of chilies from Chilli Kampung Manangah Solok Selatan, Chilli Lotanbar Limapuluh Kota, Chilli Local Dharmasraya 1, Chilli Local Maninjau, Chilli Local Tanah Datar, Chilli Ateng Maninjau, Chilli Local Pesisir Selatan, Chilli Ateng Pasaman Barat, Chilli Local Sijunjung, Chilli Kuhay Padang Pariaman, Chilli Akar Solok Selatan, and Chilli Local Dharmasraya 2. Chilli Kuhay Padang Pariaman, and Chilli Akar Solok Selatan, have the closest relationship, 94%. In general, the chilies resulting from the exploration had narrow criteria for diversity except for the observation of fruit length of the Chilli Local Maninjau variety.
Effect of bokashi quail manure and rice husk biochar on soil pH and soybean plants growth
Authors: Andayani S , Hayat E S , Mursalin A
Published: May 2023

The availability of fertile land is currently increasingly limited, so land use leads to suboptimal land. Suboptimal land constraints are low elements of N, P, K, S, and microelements, low soil pH, the possibility of Al and Fe poisoning. The use of bokashi quail manure and rice husk biochar is expected to overcome suboptimal land constraints. The objective of this study is to apply the best amount of bokashi and biochar to soybean plants in poor soil. The study employed a completely randomized design, a field experiment methodology. The study used two types of treatments: bokashi quail dung, which came in doses of 15, 30, and 45 grams per polybag, and rice husk biochar, which came in doses of 15, 30, and 45 grams per polybag. According to the study’s findings, applying bokashi 30 grams per polybag along with 15 grams of rice husk biochar per polybag could lead to the greatest rise in soil pH when compared to other treatments. The use of bokashi quail manure alone, at doses between 30 and 45 grams per polybag, can result in the highest plant height and number of leaves compared to other treatments.
Application of local resource-based amelioration technology on the chemical properties of Inceptisols in monoculture and polyculture cultivation systems
Authors: Herviyanti H , Maulana A , Habazar T , Noer M , Lita R P , Refdi C W , Fathi A N M , Monikasari M
Published: May 2023

The impact of using chemical fertilizers in the cultivation system changes the soil’s physicochemical characteristics. Local resources-based amelioration technology can be used as a solution to increase soil fertility and plant productivity. This study aimed to measure changes in the chemical properties of Inceptisols in monoculture and polyculture cultivation systems. A randomized block design was used in this research with eight treatments and three replications. Treatments were carried out with equivalent doses: control; bamboo biochar (BB)+ Tithonia green fertilizer(TGF)+manure+compost; BB+TGF+manure; BB+TGF+compost; BB+manure+compost; TGF+manure+compost; conventional technique and Ministry of Agriculture recommendation (MAR). The results showed that the addition of ameliorant tended to have higher pH than conventional and control. The highest organic-C of the monoculture was obtained in TGF+manure+compost, which was 0.39; 0.49; and 0.47 more elevated compared to the control, conventional technique, and MAR. Meanwhile, the highest organic-C in the polyculture system was found in BB+TGF+manure and almost the same as BB+manure+compost, but higher by 1.15, 1.01, and 1.01 compared to control, conventional, and MAR. The available-P in the monoculture system was almost the same for all treatments, while for the polyculture system, BB+manure+compost, BB+manure+compost, and MAR showed that the values were almost the same and higher than the others.
Optimization on co-composting of horse manure with pineapple waste composition using Response Surface Methodology (RSM)
Authors: Mohd Sokri S S , Tee T P , Nurin A M Y , Azhar S , Nayan N , Hj Suyub I B
Published: May 2023

Horse manure (HM) content of nitrogen and phosphorus can improve soil nutrient as organic fertilizer. Biodegradable pineapple waste (PW) contains high organic carbon, which is also a good bulking agent if appropriately treated with HM through co-composting to optimize the better quality of the co-compost product. The study objective was to optimize the composting quality of HM with PW via response surface methodology (RSM). Twenty treatments based on 3 level codes (-α, 0, +α) of three compositing factors, namely co-composting period (20, 25, 30 days), percentage of composition HM: PW (85:15, 90:10, 95:5) and particle size of PW (0.25, 0.50, 0.75 cm), respectively were designed using the central composite design (CCD). At the end of composting period, the carbon to nitrogen ratio (C/N), dry matter (DM), organic matter (OM), moisture content (MC), bulk density and pH were determined as co-compost qualities (dependent responses). The optimum results indicated that the Day 20 of composting period, composition 95:5 (HM: PW) and 0.25 cm of particle size had significant optimum values of 27.2 % DM, 72.8 % MC, 90.3 % OM and pH 6.7. No significant interaction of the three factors was found on C/N ratio and bulk density by RSM analysis. Subsequently, the significant results of optimum value developed a prediction model for co- composting HM and PW.
Study on physical properties of rangeland at some slope levels in Nagari Aie Dingin, District of Lembah Gumanti, Solok Regency
Authors: Variastuti S , Herviyanti  , Yulnafatmawita
Published: May 2023

A field study was carried out in Nagari Aie Dingin, Lembah Gumanti District, Solok Regency. This research was aimed to examine the physical properties of Inceptisols at several slope levels in the research location. The soil samples were taken by purposive sampling based at slope levels (slightly steep [8-15%], moderately steep [15-25%], steep [25-45%], and very steep [>45%]), and in coffee field (25-45%) for two soil depths (0-30 cm and 30-60 cm). The results showed that the research area had silt loam, silty clay loam, and silt clay in texture. By increasing slope level (from 8-15% to >45%), soil organic matter content tended to decrease (from 5.74 to 2.58), bulk density increased (from 0.58 to 0.79 g/cm3), total soil porosity decreased (from 71.20 to 62.80), permeability rate decreased (from 9.47 to 4.01), for both soil depths (0-30 cm and 30-60 cm). Meanwhile, aggregate stability index was considered moderate. Compared to the land under coffee cultivation, the level of soil physical properties under the rangeland was still lower than that under coffee plantation. There was a negative correlation between SOM and soil BD (r (0-30 cm) = -0.85 and r (30-60 cm) = -0.69) and positive correlation between SOM and STP (r (0-30 cm) = 0.95, r (30-60 cm) = 0.80) and between SOM and soil permeability (r (0-30 cm) = 0.37, r (30-60 cm) = 0.85). Based on the fact, it is suggested to apply appropriate cultivation techniques and to provide suitable input in improving the soil physical properties.
Restoration of soil chemical and mercury content in former mining land with the application of biochar, manure and clay for the sunflower growth and production
Authors: Gusmini  , Arlius F , Adrinal  , Fauzan R , Putri E L
Published: May 2023

The former gold mining land is a land that has a deficient fertility level and is contained heavy metals such as mercury (Hg). The purpose of this research is to study the role of biochar, manure, and clay and the role of sunflowers in reducing mercury (Hg) in the restoration of the former gold mining land. The researcher used a random design method with groups of 3 treatments and 3 repetitions. The treatment consists of 0 ton/ha, 10 ton/ha, and 20 ton/ha biochar, manure, and clay. The result of this research shows the effect of biochar, manure, and clay in reviving the chemical properties of the soil and able to reducing mercury levels in the soil and increasing the production of sunflowers. The best treatment happened in the dose of 20 tons/ha, increasing the chemical properties with the value pH 6.12, P-available 30,89 ppm, C-organic 2,457%, N-total 0,1459%, CEC 23.87 me.100g-1, K-dd 0,1309 me.100g-1, Mg-dd 0,254 me.100g-1, Na-dd 0,116 me.100g-1, Hg 19,748 ppm, sunflower production 4,14 g/100 seeds and sunflowers able to accumulate mercury in the trunk 15,05 ppm and 6,69 ppm in the root.
Role of coffee plantation in reducing erosion under coarse textured soil in wet tropical region
Authors: Yulnafatmawita  , Maira L , Gusmini  , Edwin
Published: May 2023

Water erosion is one phenomenon causing land degradation in a wet area. The research was aimed to evaluate the total of soil erosion under coffee plantations having coarse textured soil in wet tropical regions. This research was taken out on a coffee plantation in Sibarasok, Maninjau having rather to very steep slope and high annual rainfall, with Inceptisol soil order. Soil samples were taken from 6 land units (Coffee-86 y having 0-8%, 25-45%, and >45%, Coffee 5 y-15-25%, Coffee 8 y-25-45%, and forest >45% as control). The samples of soil were prepared and analyzed in the Laboratory of Soil, Department of Soil Science and Land Resource, Andalas University. The actual amount of soil eroded was predicted using the USLE formula. Then, it was compared to the tolerated (Etol) soil erosion. The result showed that the predicted amount of soil eroded was quite low (<10 T/Ha/y), except under coffee having >45% slope. The highest soil eroded in the very steep slope was due to its low SOM content and permeability, with an erosion hazard level of 1.2. Compared to tolerated erosion (Etol), the actual soil erosion predicted was lower than the Etol. The fiber roots of the coffee dominating the top 5 cm of soil surface as well as high SOM content and hydraulic conductivity rate caused the soil on the top to become tightly held avoiding erosion.
Changes in soil chemical properties due to conversion of rubber plantation land to food crops with a slash-and-burn system in the regency of Sijunjung, West Sumatera Indonesia
Authors: Sandi N , Naspendra Z , Juniarti  , Hendra A M
Published: May 2023

The Rubber plantation area is an agroforestry cover area that resembles a forest cover area. Recently, there have been many land conversions, both from forests to intensive agricultural areas, agroforestry to intensive agricultural areas. Land conversion is mostly carried out by the slash-and-burn method with negative impacts causing land degradation. This study was aimed to determine changes in several parameters of chemical properties on land that has undergone burning. This research had been conducted from April to August 2022 in Nagari Padang Laweh, Koto VII District, Sijunjung Regency. Then continued at the Soil Chemistry Laboratory of the Faculty of Agriculture, Andalas University. Soil samples were taken from three land uses, namely, Rubber fields, former Rubber plants that had been cut down and former Rubber plants that had been planted with Corn on the same slopes. The data obtained from the results of the analysis were processed using microsoft excel and read with a table of criteria for soil chemical properties. The results showed a decrease in several parameters of soil chemical properties on land that was converted by the slash-and-burn method. After the land was planted with food crops, there was an increase in some of the parameters of chemical properties studied.
Effective concentration of entomopathogens Beauveria bassiana (Bals) Vuil as biological control agents for Spodoptera frugiperda J.E. Smith (Lepidoptera: Noctuidae)
Authors: Nelly N , Reflinaldon  , Meriqorina S R
Published: May 2023

Fall armyworm (Spodoptera frugiperda JE Smith) is an invasive pest that attacks corn plants. This pest control can be done using several techniques. Biological control for S. frugiperda is using the entomopathogenic fungus Beauveria bassiana. The study to obtain an effective concentration of the entomopathogenic fungus B. bassiana for controlling S. frugiperda. The study was conducted at the Insect Bioecology Lab and Biological Control Laboratory, Faculty of Agriculture, Universitas Andalas. The study was designed in a Completely Randomized Design (CRD) with five treatments and was repeated five times. The treatments consist of a suspension of the fungi B. bassiana with different densities, namely 106, 107, 108, 109 conidia/ml and control (aquadest + tween 80). Parameters observed were larval mortality, percentage of Pupae formed, percentage of adults offsprings, and the number of normal and defective adults as well as male and female adults. Data were analyzed by Analysis of Variance (ANOVA), further tested with LSD at a 5% level, and analysis probit to known LC100. The results showed that the higher the concentration, the higher the mortality of the larvae. The effective suspension of B. bassiana as control of S. frugiperda was a concentration of 109, caused larvae mortality percentage of 84%, Pupae formation of 4%, adults offspring 2%, and sex ratio male: female (1:0), normal and abnormal adults 0:1. To get larvae mortality up to 100%, the LC100 is 1018 conidia/ml.
Potential of actinobacteria as biocontrol agents to Xanthomonas oryzae pv. oryzae in vitro
Authors: Rahma H , Trisno J , Martinius  , Shafira S D
Published: May 2023

Xanthomans oryzae pv. oryzae (Xoo) is a pathogen that causes bacterial leaf blight in rice plants.Biological control using microorganisms, one of which incorporates actinobacteria, is one of the most extensively used control techniques. This work aimed to find actinobacteria isolates from rice that can inhibit Xoo growth in vitro. A Completely Randomized Design (CRD) was employed in this experiment, with 14 treatments and three replications. There are 13 isolates used: Act-Hr 49, Act-Hr 21, Act-Hr 24, Act-Pha 4, Act-Mn2, Act-LB3, Act Pha 2.3, Act Pha 3.4, Act-Pha 3.3, Act-Hr 47, Act Pha 3.5, Act-Krj 21, Act-SK2 and control (Xoo without Actinobacteria treatment). The ability of actinobacterial isolates to reduce Xoo growth in vitro and the enzyme activity of each isolate were measured. The study revealed that three Actinobacteria isolates, Act-LB3, Act-Mn2, and Act-Pha4, could potentially suppress Xoo bacteria’s growth with inhibition indices ranging from 12 mm to 15 mm Act-LB3 isolate produced catalase enzyme, while Act-Pha4 isolate produced both catalase and protease enzyme. The results indicate that actinobacteria from the rice rhizosphere could produce antibacterial metabolites and enzyme activity.
Exploration of the indigenous rhizosphere fungi as corncob waste decomposers and its potential as biological agent Fusarium graminearum and increase corn growth
Authors: Nurbailis  , Liswarni Y , Yanti Y , Widiastuti A
Published: May 2023

Corncob waste can be used as compost; corncob compost that microbial decomposers have composted positively affects soil and plants. The objectives of this study are 1). It was obtaining the type of fungi from the corn rhizosphere that acts as a decomposer of corncob waste and 2) knowing the potential of corncob waste compost in suppressing F. graminearum, which causes stem rot on corn and increasing plant growth. The designs used for the two steps of the study were: Randomized Block Designs with ten treatments and four replication. The first step is using the rhizosphere fungi isolates for composting corncob waste. The second step is testing corncob composted by ten different types of rhizosphere fungi to suppress corn stem rot caused by F. graminearum. Parameters observed in the first step were: the number of conidia and the number of propagules of rhizosphere fungi in corncobs compost. The third step was: Incubation period, disease incidence, disease severity, number of dead plants, and plant growth. The result of the research indicated that the corn rhizosphere obtained 15 isolates of fungi that varied the color, shape of the colony, and growth rate. The highest number of propagules was found in compost decomposed by rhizosphere fungi RF4, while the number of conidia classified as high was found in RF4, Rf, and RF6 compost. All corncob compost decomposed by rhizosphere fungi was able to suppress stem rot disease caused by F. graminearum.
The antagonistic potential of Bacillus spp. against Ralstonia solanacearum causing bacterial wilt disease in ginger (Zingiber officinale)
Authors: Sussanti D , Khairul U , Resti Z
Published: May 2023

Bacterial wilt caused by Ralstonia solanacearum is an important disease in ginger which can cause yield losses of more than 90%. One way to control the disease is by biological control using the microorganism, Bacillus. Bacillus spp. is recognized to have the ability to control pests and diverse phytopathogens through the induction of systemic resistance in plants. This study aimed to obtain Bacillus spp. that can prevent the bacterial wilt disease in ginger caused by Ralstonia solanacearum. This study was carried out at the Microbiology Laboratory and Greenhouse, Faculty of Agriculture, Universitas Andalas, from July to October 2022. The experiment introduced 5 Bacillus (Bacillus cereus Se07, Bacillus cereus P14, Bacillus sp. SJI, Bacillus sp. HI, and Bacillus subtilis) and control, inoculated with Ralstonia solanacearum at one month old. The parameters of ginger that will be observed were incubation period, disease incidence, and disease severity. The results show that the treatment of B. cereus P14 is the best ability to suppress the severity of bacterial wilt disease by 37.03% with an effectiveness of 47.38%.
The dosage of biopesticide formulation of local Metarhizium anisopliae flour in compost(metankos) against Oryctes rhinoceros L.
Authors: Fauzana H , Nelvia  , Rustam R , Puspita F , Feronica R
Published: May 2023

The Rhinoceros beetle (Oryctes rhinoceros) is the main pest that causes severe impacts on palm oil plantations. The technology for controllingO. rhinocerosis more focused on utilizing the biological agentMetarhizium anisopliae, which is added to the compost called Metankos. The study aimed to obtain the best dose of localM. anisopliaebiopesticide flour formulation on Metankos on mortality ofO. rhinoceroslarvae. The study was conducted experimentally using a completely randomized design consisting of eight treatments with four replications to obtain 32 experimental units. Each experimental unit consisted of 10 larvae ofO. rhinocerosinstar II. The treatments used several doses ofM. anisopliaeflour formulation with doses of 0, 30, 60, 90, 120, 150, 180, and 210 g/5 kg compost/bucket. The result showed that a 60 g/5 kg compost/bucket of the best compost mixed with a formulation ofM. anisopliaeflour induced a 52.5% mortality rate forO. rhinoceroslarvae.
Fungicidal activity nanoemulsions of citronella oils (Cymbopogon nardus L.) against rice seed-borne pathogenic fungi
Authors: Harahap R F , Martinius  , Darnetty
Published: May 2023

Rice seed-borne pathogenic fungi are one of the causes of decreased rice productivity. Nanoemulsion of citronella oil is an alternative control for seed-borne pathogenic fungi carried by rice seeds and is effective and environmentally friendly. The research aimed to determine the effective concentration of nanoemulsions of citronella oil in controlling rice seed-borne pathogenic fungi. The study was conducted in two stages: 1. In the laboratory using a completely randomized design (CRD) with seven treatments and four replications. 2. Greenhouse uses the same design and treatment in stage one. The treatments used were control (soaking using sterile distilled water), nanoemulsion of citronella oil concentrations of 0.40%, 0.45%, 0.50%, 0.55%, 0.60%, and synthetic fungicide with propineb active site (70 WP) at a 2 g/l. The data obtained were analyzed using variance with the advanced test of Least Significance Different (LSD) at the 5% level. The parameters observed were the percentage of rice seeds that were attacked by fungi, identification of seed-borne pathogenic fungi, percentage of rice seeds that were attacked by each fungus, percentage of seedlings that appeared in the field, percentage of seedlings attacked by fungi, percentage of dead seedlings, seedling height, fresh and dry weight of seedlings. The result showed that nanoemulsion with a concentration of 0.50% was the most effective in controlling rice seed-borne pathogenic fungi, with the effectiveness of seeds being attacked suppressed by fungus, seedlings appearing in the field, seedlings being attacked by fungus, dead seedlings, seedling height, fresh and dry weight seeds were 75.00%, 60.00%, 100.00%, 100.00%, 60.83%, 141.55%, 366,67% respectively.
Mixed rice husk ash and powder of Piper aduncum fruit as an alternative control of Spodoptera frugiperda in corn plants
Authors: Lina E C , Buana M P , Nelly N , Refrinaldon  , Reflin
Published: May 2023

The insecticidal activity of Piper aduncum fruit has been reported, and the rice husk ash is well used as an alternative control of the new invasive pest Spodoptera frugiperda. This research aimed to determine the effectiveness of a mixture rice husk ash andP. aduncumfruit powder as an alternative control ofS. frugiperdaon maize. The study was conducted using a Completely Randomized Design (CRD), including preliminary and follow-up tests. The test used the sowing method on the leaf, consisting of five treatments plus control and five replications. Observation parameters were larval mortality, larval development time, percentage of pupae formed, rate of imago appearing, and sex ratio. In general, a single treatment ofP. aduncumfruit powder and rice husk ash can cause the death ofS. frugiperdalarvae, inhibit the development of larvae that survive after treatment, and reduce the percentage of pupae and imago when compared to controls. It also affects the ratio of males and females of imago appearance. Probit analysis of the mixed treatment ofP. aduncumfruit powder and rice husk ash (1:1) showed the LC50 and LC95 values were 2.06 g and 12.93 g, respectively. A mixture of rice husk ash andP. aduncumfruit powder can be used as an alternative to controlS. frugiperdawith the index combination value at the LC50 and LC95level were 0.58 and 0.65 respectively, which indicates the index combination is a weak synergistic.
Suppression of joint predators (Pardosa pseudoannulata and Verania lineata) against Nilaparvata lugens in conditions exposed to MIPC insecticide
Authors: Utari A , Syahrawati M , Arneti  , Rusli R , Busniah M , Siregar R W , Putra N S
Published: May 2023

MIPC is one of the insecticides widely used by farmers to control brown planthopper or BPH (Nilaparvata lugens) in Padang City, Indonesia. Excessive use of insecticides can cause BPH to become resistant, followed by the death of natural enemies. This study aimed to determine the suppression of joint predators (Pardosa pseudoannulata and Verania lineata) against Nilaparvata lugens under MIPC Insecticide Exposure Conditions. This study used a Completely Randomized Design (CRD) factorial with two factors and five replications. The first factor was the dose of MIPC insecticide (0.75 g/l, 1.5 g/l, 2.25 g/l, and without application) and the second factor was the time of application (During BPH infestation and joint predators, before BPH infestation and joint predators, after WBC infestation and before joint predator infestation). The parameter observed were predation, body weight, and mortality. The results showed no interaction between dose and time of application on joint predator predation. Increasing the MIPC dose decreased the predation. Joint predators could suppress BPH populations of 40.6-43.6 individuals (78-81%) per day, but MIPC application and the presence of joint predators together reduced their predation rates. It is better to apply MIPC insecticide before or after the presence of joint predators to avoid negative impacts on joint predators.
The role of healthy citrus planting materials production as a major component in the development of national citrus industry
Authors: Harwanto  , Siregar A S , Mufidah L , Hanif Z , Zamzami L , Aji T G , Budiarto K
Published: May 2023

Certified citrus seed is one of vital component on the program of good agricultural practices for the development of healthy citrus plantation. Certified seed guarantee the free systemic disease and optimum vigor planting material, thus put an impact on maximum physiological response to the agriculture inputs that being applied. Production of healthy planting material is initially started from the acquisition of free diseases protocol of seeds from breeder seeds. However, there are still many issues regarding bud-stick in Indonesia which cause the spread of systemic diseases, one of which is CVPD/Huanglongbing (HLB). Therefore, this article presents a descriptive review of the important role of healthy citrus planting materials production that meets the requirements, so that it can become a reference for the citrus nurseries. There are several factors (limited availability of citrus planting materials, technology components to produce healthy seedlings that are not fully applied, as well as the partial application of certified citrus planting materials) that could inhibit the use of technology by the citrus nurseries. A number of recommendations from literatures to overcome these problems are the use of effective dissemination and extension methods, also the provision of understanding and supervision that is carried out on an ongoing basis.
Entrepreneurial competencies and farm management performance of potato farmers in Solok Regency
Authors: Yusmarni  , Putri A , Paloma C
Published: May 2023

Solok Regency has excellent potential in growing vegetables and fruit, which significantly contribute to West Sumatra’s economy. Solok Regency is the largest potato-producing area in West Sumatra. However, since 2015 there has been a drastic decline in potato production. The negative growth of potato production was affected by several factors, including sub-optimal farming management. Farmers’ lack of passion and entrepreneurial ability is one of the socioeconomic factors that hinder the development of their potential in managing productive businesses in rural areas. This paper analyses the entrepreneurial competency of potato farmers in Solok Regency and examines the effect of entrepreneurial competency on the farm management performance of potato farmers in Solok Regency. This study finds that the level of entrepreneurial competency of potato farmers is at a moderate level. Moreover, PLS path analysis found that the variables of individual characteristics of farmers, entrepreneurial characteristics, and business environment are a reference in measuring the entrepreneurial competency of Potato Farmers. Furthermore, entrepreneurial competency, individual characteristics of farmers, entrepreneurial characteristics, and business environment positively and significantly affect the farm management performance of Potato Farmers in Solok Regency. Farmer entrepreneurs do not work alone. However, they operate in a complex and dynamic environment. Despite the level of farmers’ competency ranging from moderate to high, it needs support from other parties to give farmers access to superior seeds and better prices for inputs and output.