scholarly journals Organic Soils Control Beetle Survival While Competitors Limit Aphid Population Growth

2019 ◽  
Vol 48 (6) ◽  
pp. 1323-1330 ◽  
Author(s):  
Karol L Krey ◽  
Carmen K Blubaugh ◽  
James T Van Leuven ◽  
William E Snyder
Keyword(s):  
Management Practices ◽  
Solanum Tuberosum L ◽  
Management Strategies ◽  
Soil Management ◽  
Farming Systems ◽  
Colony Growth ◽  
Organic Soils ◽  
Potato Plants ◽  
Mediated Effects ◽  
Herbivore Species

Abstract Soil chemistry and microbial diversity can impact the vigor and nutritive qualities of plants, as well as plants’ ability to deploy anti-herbivore defenses. Soil qualities often vary dramatically on organic versus conventional farms, reflecting the many differences in soil management practices between these farming systems. We examined soil-mediated effects on herbivore performance by growing potato plants (Solanum tuberosum L.) in soils collected from organic or conventional commercial farm fields, and then exposing these plants to herbivory by green peach aphids (Myzus persicae Sulzer, Hemiptera: Aphididae) and/or Colorado potato beetles (Leptinotarsa decemlineata Say, Coleoptera: Chrysomelidae). Responses of the two potato pests varied dramatically. Survivorship of Colorado potato beetles was almost 3× higher on plants grown in organic than in conventional soils, but was unaffected by the presence of aphids. In contrast, aphid colony growth was twice as rapid when aphids were reared alone rather than with Colorado potato beetles, but was unaffected by soil type. We saw no obvious differences in soil nutrients when comparing organic and conventional soils. However, we saw a higher diversity of bacteria in organic soils, and potato plants grown in this soil had a lower carbon concentration in foliar tissue. In summary, the herbivore species differed in their susceptibility to soil- versus competitor-mediated effects, and these differences may be driven by microbe-mediated changes in host plant quality. Our results suggest that soil-mediated effects on pest growth can depend on herbivore species and community composition, and that soil management strategies that promote plant health may also increase host quality for pests.

scholarly journals Rural Roads Are Paving the Way for Land-Use Intensification in the Uplands of Laos

Land ◽  
2021 ◽  
Vol 10 (3) ◽  
pp. 330
Author(s):  
Jean-Christophe Castella ◽  
Sonnasack Phaipasith
Keyword(s):  
Land Use ◽  
Management Practices ◽  
Management Strategies ◽  
Farming Systems ◽  
Long Term Effects ◽  
Group Discussions ◽  
Rural Roads ◽  
External Resources ◽  
Hybrid Maize ◽  
The Impact

Road expansion has played a prominent role in the agrarian transition that marked the integration of swidden-based farming systems into the market economy in Southeast Asia. Rural roads deeply altered the landscape and livelihood structures by allowing the penetration of boom crops such as hybrid maize in remote territories. In this article, we investigate the impact of rural road developments on livelihoods in northern Laos through a longitudinal study conducted over a period of 15 years in a forest frontier. We studied adaptive management strategies of local stakeholders through the combination of individual surveys, focus group discussions, participatory mapping and remote-sensing approaches. The study revealed the short-term benefits of the maize feeder roads on poverty alleviation and rural development, but also the negative long-term effects on agroecosystem health and agricultural productivity related to unsustainable land use. Lessons learnt about the mechanisms of agricultural intensification helped understanding the constraints faced by external interventions promoting sustainable land management practices. When negotiated by local communities for their own interest, roads may provide livelihood-enhancing opportunities through access to external resources, rather than undermining them.

scholarly journals Biophysical and socio-economic tools for assessing soil fertility: A case of western hills, Nepal

2013 ◽  
Vol 1 ◽  
pp. 1-9 ◽  
Author(s):  
BP Tripathi ◽  
JE Jones
Keyword(s):  
Soil Fertility ◽  
Management Practices ◽  
Management Strategies ◽  
Soil Management ◽  
Cost Effective ◽  
Integrated System ◽  
Residue Management ◽  
Soil Fertility Management ◽  
Fertility Management ◽  
Early Results

The middle mountain region of Nepal, which occupies some 30% of the total land, is the homeland of 45% of the total population, with agriculture being the main source of their livelihoods. Hill farming is primarily based on organic manure with livestock, forest and crops being major components of an integrated system. The aim of this study is to develop and promote improved methods for research and development organizations to identify cost-effective and appropriate soil fertility management strategies through; providing an improved understanding of the biophysical and socio-economic factors affecting the adaptability of sustainable soil management strategies in hillside systems, developing methodologies for evaluating soil fertility technologies and management systems for differently resource farmers in different farming systems, and strengthening the capability of local professionals in collaborating institutions to provide useful information to farmers. The work is placing emphasis on promoting cost-effective methods of soil fertility management, building on farmers' own knowledge and systems. Participatory techniques have been used for gaining a better understanding of fertility indicators, trends and existing soil management practices during 2000/01 in the western hills of Nepal. Farmers are now concerned that increasing amounts of chemical fertilizer at increasingly higher cost have to be applied, soils are becoming “harder” and production is declining. As a result farmers in four agro-ecological zones opted to either test methods for “improving” the quality of farm yard manure (FYM), or “improve” crop residue management. Early results show that through covering the FYM with black plastic sheets, yield increases of over 30% can be achieved. The use of participatory farm management techniques is providing a basis for local NGOs and farmers to evaluate their own experiments and develop soil fertility technologies and systems for their environments.DOI: http://dx.doi.org/10.3126/ajn.v1i0.7536 Agronomy Journal of Nepal (Agron JN) Vol. 1: 2010 pp.1-9

scholarly journals Endophytic Colonization of Potato (Solanum tuberosum L.) by a Novel Competent Bacterial Endophyte, Pseudomonas putida Strain P9, and Its Effect on Associated Bacterial Communities

2009 ◽  
Vol 75 (11) ◽  
pp. 3396-3406 ◽  
Author(s):  
Fernando Dini Andreote ◽  
Welington L. de Araújo ◽  
João L. de Azevedo ◽  
Jan Dirk van Elsas ◽  
Ulisses Nunes da Rocha ◽  
...  
Keyword(s):  
Pseudomonas Putida ◽  
Microbial Communities ◽  
Pseudomonas Syringae ◽  
Denaturing Gradient Gel Electrophoresis ◽  
Solanum Tuberosum L ◽  
Linear Regression Analysis ◽  
Colony Growth ◽  
Group Method ◽  
Growth Stages ◽  
Potato Plants

ABSTRACT Pseudomonas putida strain P9 is a novel competent endophyte from potato. P9 causes cultivar-dependent suppression of Phytophthora infestans. Colonization of the rhizoplane and endosphere of potato plants by P9 and its rifampin-resistant derivative P9R was studied. The purposes of this work were to follow the fate of P9 inside growing potato plants and to establish its effect on associated microbial communities. The effects of P9 and P9R inoculation were studied in two separate experiments. The roots of transplants of three different cultivars of potato were dipped in suspensions of P9 or P9R cells, and the plants were planted in soil. The fate of both strains was followed by examining colony growth and by performing PCR-denaturing gradient gel electrophoresis (PCR-DGGE). Colonies of both strains were recovered from rhizoplane and endosphere samples of all three cultivars at two growth stages. A conspicuous band, representing P9 and P9R, was found in all Pseudomonas PCR-DGGE fingerprints for treated plants. The numbers of P9R CFU and the P9R-specific band intensities for the different replicate samples were positively correlated, as determined by linear regression analysis. The effects of plant growth stage, genotype, and the presence of P9R on associated microbial communities were examined by multivariate and unweighted-pair group method with arithmetic mean cluster analyses of PCR-DGGE fingerprints. The presence of strain P9R had an effect on bacterial groups identified as Pseudomonas azotoformans, Pseudomonas veronii, and Pseudomonas syringae. In conclusion, strain P9 is an avid colonizer of potato plants, competing with microbial populations indigenous to the potato phytosphere. Bacterization with a biocontrol agent has an important and previously unexplored effect on plant-associated communities.

scholarly journals Impacts of soil management practices on soil fertility in potato-based cropping systems in the Bolivian Andean highlands

2010 ◽  
Author(s):  
◽  
Javier Aguilera Alcón
Keyword(s):  
Soil Fertility ◽  
Plant Tissue ◽  
Management Practices ◽  
Solanum Tuberosum L ◽  
Chenopodium Quinoa ◽  
Soil Management ◽  
Organic Fertilizers ◽  
Organic C ◽  
Sheep Manure ◽  
Andean Highlands

Due to changes in climate and socioeconomic developments, current soil management practices in the Bolivian Andean Highlands may be increasing soil degradation thereby threatening food security. A study was established in four representative communities during the 2006-09 growing seasons to identify an integrated soil management strategy that may help to improve soil fertility and productivity by increasing soil organic matter. Soil samples collected from fields of different lengths of cropping (LC) and fallow (LF) showed that LC decreased and LF increased total (TOC) and active soil organic C (AOC), and total (TN), inorganic (TIN) and active soil N (AIN). Field trials established with combinations of soil inorganic fertilizers (SIF) and local and alternative soil organic fertilizers (i.e., cow and sheep manure, household compost and a biofertilizer) revealed that the cow and sheep manure combined with SIF significantly affected soil properties, such as pH, soil test P, TN, TIN and TOC, soil water content and bulk density and significantly increased the production of potato (Solanum tuberosum L.) and a subsequent quinoa (Chenopodium quinoa Willd.) crop. Results of testing a portable field method to assess N status of potato plant tissue suggest that use of the Cardy nitrate-N meter may have some promise for tissue testing for potato in the Andean highlands of Bolivia, where access to soil and plant tissue testing services is limited.

scholarly journals Simulating farm income under the current soil management regime in the mid-hills of Nepal

2011 ◽  
Vol 6 (8) ◽  
pp. 27-34
Author(s):  
Gopal Datt Bhatta ◽  
Nilhari Neupane
Keyword(s):  
Urban Areas ◽  
Management Practices ◽  
Regional Scale ◽  
Soil Management ◽  
Farming Systems ◽  
Farm Income ◽  
Strategy Formulation ◽  
Soil Quality Index ◽  
Management Regime ◽  
Spatial Environment

Farmers in the mid-hills of Nepal follow diverse farming systems. The peri-urban area of this region, where population density is higher, faces several problems in farming. While hills suffer from erosion because they are erodible, the peri-urban areas face the problem of decline in factor productivity, particularly in intensively cultivated farmlands. The present study is concerned with simulating farm income on a regional scale based on soil management practices. Spatial explicit simulation shows that the loss of farm income due to degradation is substantially higher in hills while it is lower in valley bottoms. Strategy formulation and testing in the spatial environment indicates that Geographic Information System is an appropriate methodological tool for simulating the consequences of particular interventions. Key words: Mid hills, Nepal, spatial modeling, soil quality index, farm income DOI: http://dx.doi.org/10.3126/hjs.v6i8.3243 Himalayan Journal of Sciences Vol.6 Issue 8 2010 pp.27-34

scholarly journals Soil Properties and Soil Management Practices in Commercial Organic and Conventional Vegetable Farms in Kathmandu Valley

2015 ◽  
Vol 15 (1) ◽  
pp. 13-22
Author(s):  
Gautam Shrestha
Keyword(s):  
Soil Properties ◽  
Nitrogen Content ◽  
Soil Nitrogen ◽  
Management Practices ◽  
Soil Management ◽  
Farming Systems ◽  
Kathmandu Valley ◽  
Organic Farm ◽  
Organic Farmers ◽  
Conventional Farm

Soil management practices determine the long term productivity of soil. A comparative study of commercial organic and conventional vegetable farming systems was carried out to find out impact of different farming systems on soil properties. This study was executed in Kathmandu valley (Kathmandu, Bhaktapur and Lalitpur districts) among 30 organic and 30 conventional commercial vegetable farmers. Semi-structured questionnaire survey and soil physical and chemical analysis were performed to gather the required information. Results showed that bulk soil pH was significantly higher in the organic field than in the conventional field. Soil organic matter and available soil potassium were significantly higher in amount in the organic farm than in the conventional farm. Total soil nitrogen content and available soil nitrogen content were significantly higher in amount in the conventional farm than in the organic farm. Conventional farmers were applied significantly higher amount of chicken manure and biozyme as compared to organic farmers. Organic farmers applied significantly higher amount of urban compost and bone meal as compared to conventional farmers.  Farmers perceived productivity was increasing in trend in the organic farms whereas it was declining in the conventional farms.DOI: http://dx.doi.org/10.3126/njst.v15i1.12005 Nepal Journal of Science and TechnologyVol. 15, No.1 (2014) 13-22

scholarly journals Long-Term Management Affects the Community Composition of Arable Soil Seedbanks

Weed Science ◽  
2016 ◽  
Vol 65 (1) ◽  
pp. 73-82 ◽  
Author(s):  
Roser Rotchés-Ribalta ◽  
Laura Armengot ◽  
Paul Mäder ◽  
Jochen Mayer ◽  
Francesc Xavier Sans
Keyword(s):  
Community Composition ◽  
Management Practices ◽  
Control Strategies ◽  
Management Strategies ◽  
Farming Systems ◽  
Conventional Farming ◽  
Weed Diversity ◽  
Organic And Conventional Farming ◽  
Term Management

The intensification of farming practices has reduced weed infestations, but it has also led to a reduction in weed diversity and changes in species composition. These effects are well described for aboveground flora; however, it is less clear how these effects might be expressed in the soil weed seedbank. We evaluated the effects of different long-term farm management strategies on the weed seedbank abundance, diversity, and community composition in the DOK (bioDynamic, bioOrganic, and Konventionell) field trial established in 1978 at Therwil, Switzerland. The trial compares biodynamic, organic, and conventional farming systems, which mainly differ in fertilization, weed control strategies, and pest control. The species richness and seed abundance of the weed seedbank were higher in the organic and biodynamic systems compared with the conventional ones. The different farming systems favored shifts in species assemblages, because specific management practices, such as herbicide application and type of fertilization, acted as filters that selected against certain species but promoted others that were more adapted.

The management of risk in a dryland environment

2011 ◽  
pp. 13-21
Author(s):  
D.I. Gray ◽  
J.I. Reid ◽  
D.J. Horne
Keyword(s):  
Risk Management ◽  
Service Providers ◽  
Management Strategies ◽  
Subterranean Clover ◽  
Farming Systems ◽  
Market Risk ◽  
Farm Size ◽  
Forage Crops ◽  
Risk Management Strategies ◽  
Upside Risk

A group of 24 Hawke's Bay hill country farmers are working with service providers to improve the resilience of their farming systems. An important step in the process was to undertake an inventory of their risk management strategies. Farmers were interviewed about their farming systems and risk management strategies and the data was analysed using descriptive statistics. There was considerable variation in the strategies adopted by the farmers to cope with a dryland environment. Importantly, these strategies had to cope with three types of drought and also upside risk (better than expected conditions), and so flexibility was critical. Infra-structure was important in managing a dryland environment. Farmers chose between increased scale (increasing farm size) and geographic dispersion (owning a second property in another location) through to intensification (investing in subdivision, drainage, capital fertiliser, new pasture species). The study identified that there may be scope for further investment in infra-structural elements such as drainage, deeper rooting alternative pasture species and water harvesting, along with improved management of subterranean clover to improve flexibility. Many of the farmers used forage crops and idling capacity (reduced stocking rate) to improve flexibility; others argued that maintaining pasture quality and managing upside risk was a better strategy in a dryland environment. Supplementary feed was an important strategy for some farmers, but its use was limited by contour and machinery constraints. A surprisingly large proportion of farmers run breeding cows, a policy that is much less flexible than trading stock. However, several farmers had improved their flexibility by running a high proportion of trading cattle and buffer mobs of ewe hoggets and trade lambs. To manage market risk, the majority of farmers are selling a large proportion of their lambs prime. Similarly, cattle are either sold prime or store onto the grass market when prices are at a premium. However, market risk associated with the purchase of supplements and grazing was poorly managed.

BİLGİ YÖNETİMİ UYGULAMALARI KAPSAMINDA İNSAN KAYNAKLARI YÖNETİMİNDE MEYDANA GELEN DEĞİŞİMLER

2013 ◽  
Vol 1 (1) ◽  
pp. 83
Author(s):  
Ozan Büyükyılmaz
Keyword(s):  
Knowledge Management ◽  
Human Resources ◽  
Performance Management ◽  
Management Practices ◽  
Human Resources Management ◽  
Management Strategies ◽  
Resources Management ◽  
Management Philosophy ◽  
Management Processes

The development and expansion of knowledge management as an important management philosophy has a significant impact on human resources management as well as on organization as a whole. In this context, knowledge management processes have been used as a strategic tool within human resources management.Therefore, functions of human resources management must adapt itself to this change. The purpose of this study is to determine the role of human resources management in the management of knowledge and to reveal the effects of knowledge management practices on the functions of human resources byexamining the relationship between human resources and knowledge management. In this context, a theoretical investigation was conducted. It has been determined that significant changes occurred on the functions of human resources management such as selection and recruitment, performance management, remuneration and reward, training and development within the framework of the knowledge management strategies.

Uji Toksisitas Beberapa Fungisida Nabati terhadap Penyakit Layu Fusarium (Fusarium oxysporum) pada Tanaman Kentang (Solanum tuberosum L.) secara In Vitro (Toxicity Test of several Biofungicides in controlling Fusarium wilt (Fusarium oxysporum) in Potato Plants (Solanum tuberosum L.) by In Vitro)

2019 ◽  
Vol 9 (2) ◽  
pp. 91
Author(s):  
Ghea Dotulong ◽  
Stella Umboh ◽  
Johanis Pelealu
Keyword(s):  
Solanum Tuberosum ◽  
Fusarium Oxysporum ◽  
Fusarium Wilt ◽  
Leaf Extract ◽  
Solanum Tuberosum L ◽  
In Vitro Toxicity ◽  
Potato Plants ◽  
Colony Diameter ◽  
In Vitro Toxicity Test

Uji Toksisitas Beberapa Fungisida Nabati terhadap Penyakit Layu Fusarium (Fusarium oxysporum) pada Tanaman Kentang (Solanum tuberosum L.) secara In Vitro (Toxicity Test of several Biofungicides in controlling Fusarium wilt (Fusarium oxysporum) in Potato Plants (Solanum tuberosum L.) by In Vitro) Ghea Dotulong1*), Stella Umboh1), Johanis Pelealu1), 1) Program Studi Biologi, FMIPA Universitas Sam Ratulangi, Manado 95115*Email korespondensi: [email protected] Diterima 9 Juli 2019, diterima untuk dipublikasi 10 Agustus 2019 Abstrak Tanaman kentang (Solanum tuberosum L.) adalah salah satu tanaman hortikultura yang sering mengalami penurunan dari segi produksi dan produktivitasnya, akibat adanya serangan penyakit layu yang salah satunya disebabkan oleh Fusarium oxysporum. Tujuan penelitian ini adalah mengidentifikasi toksisitas beberapa fungisida nabati dalam mengendalikan penyakit Layu Fusarium (F. oxysporum) pada tanaman kentang (Solanum tuberosum L.) secara In Vitro. Metode Penelitian yang digunakan yaitu metode umpan beracun. Data dianalisis dengan Rancangan Acak Lengkap (RAL) dengan Analisis Varian (ANAVA) yang dilanjutkan dengan menggunakan metode BNT (Beda Nyata Terkecil). Hasil Penelitian, diperoleh nilai toksisitas fungisida nabati tertinggi yaitu pada ekstrak daun sirsak dengan nilai HR (69,44%), kategori berpengaruh, ditandai dengan diameter koloni 2,75 cm (100ppm) dan yang terendah toksisitasnya yaitu pada ekstrak daun jeruk purut dengan nilai HR (49,81%), kategori cukup berpengaruh ditandai dengan diameter koloni 3,75 cm (25ppm). Semakin tinggi konsentrasi yang diujikan maka semakin tinggi toksisitas dari fungisida nabati yang diberikan.Kata Kunci: fungisida nabati, Fusarium oxysporum, tanaman kentang, In Vitro Abstract Potato plants (Solanum tuberosum L.) is one of the horticulture plants which often decreases in terms of production and productivity, due to the attack of wilt, one of which is caused by Fusarium oxysporum. The purpose of this study was to determine the toxicity of several biofungicides in controlling Fusarium wilt (F. oxysporum) in potato plants (Solanum tuberosum L.) in Vitro. The research method used was the In Vitro method with the poison bait method. Data were analyzed by Completely Randomized Design with Variant Analysis (ANAVA), followed by the BNT method. The results showed that the highest biofungicide toxicity value was soursop leaf extract with HR values (69.44%), influential categories, characterized by colony diameter 2.75 cm (100ppm) and the lowest toxicity, namely in kaffir lime leaf extract with a value of HR (49.81%), quite influential category was characterized by colony diameter of 3.75 cm (25ppm). The higher the concentration tested, the higher the toxicity of the biofungicide given.Keywords: biofungicides, Fusarium oxysporum, Potato Plants, In Vitro.

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