Developments in pesticide application for the small-scale farmer in the tropics

1981 ◽  
Vol 10 (7) ◽  
pp. 345-349 ◽  
Author(s):  
G A Matthews
Keyword(s):  
Crop Protection ◽  
Small Scale ◽  
Weed Competition ◽  
Pesticide Application ◽  
Peasant Farmer ◽  
Recent Developments ◽  
The Tropics ◽  
High Degree ◽  
Spinning Disc ◽  
Small Scale Farmer

Hydraulic sprayers, which have reached a high degree of sophistication, have long been seen as inappropriate for use in many countries where crops are most at risk from pest, disease and weed competition. ULV application by spinning-disc sprayer may have overcome problems of inadequate water supply, but, for many, costs are still too high. Recent developments in electrostatic sprayers could remove this final constraint to adequate crop protection for the peasant farmer.

Genetic Diversity of Basil (Ocimum spp. - Lamiaceae) Based on RAPD Markers and Volatile Oil Constituents

HortScience ◽  
1998 ◽  
Vol 33 (3) ◽  
pp. 492f-493
Author(s):  
Roberto F. Vieira ◽  
James E. Simon ◽  
Peter Goldsbrough ◽  
Antonio Figueira
Keyword(s):  
Genetic Diversity ◽  
Molecular Markers ◽  
Rapd Markers ◽  
Volatile Oil ◽  
Essential Oil Composition ◽  
Oil Composition ◽  
Traditional Medicines ◽  
The Tropics ◽  
High Degree ◽  
First Time

Essential oils extracted from basil (Ocimum spp.) by steam distillation are used to flavor foods, oral products, in fragrances, and in traditional medicines. The genus Ocimum contains around 30 species native to the tropics and subtropics, with some species naturalized and/or cultivated in temperate areas. Interand intraspecific hybridization have created significant confusion in the botanical systematics of this genus. Taxonomy of basil (O. basilicum) is also complicated by the existence of numerous varieties, cultivars, and chemotypes within the species that do not differ significantly in morphology. In this study we are using RAPD markers and volatile oil composition to characterize the genetic diversity among the most economically important Ocimum species. We hypothesize that the genetic similarity revealed by molecular markers will more accurately reflect the morphological and chemical differences in Ocimum than essential oil composition per se. Preliminary research using five Ocimum species, four undetermined species, and eight varieties of O. basilicum (a total of 19 accessions) generated 107 polymorphic fragments amplified with 19 primers. RAPDs are able to discriminate between Ocimum species, but show a high degree of similarity between O. basilicum varieties. The genetic distance between nine species and among 55 accessions within the species O. americanum, O. basilicum, O. campechianum, O. × citriodorum, O. gratissimum, O. kilimandscharium, O. minimum, O. selloi, and O. tenuiflorum will be analyzed by matrix of similarity and compared to the volatile oil profile. This research will for the first time apply molecular markers to characterize the genetic diversity of Ocimum associate with volatile oil constituent.

scholarly journals Vegetation Diversity of Screes and Taluses of The Pamir and South-Western Tian Shan in Middle Asia

2021 ◽  
Author(s):  
Arkadiusz Nowak ◽  
Sebastian Świerszcz ◽  
Sylwia Nowak ◽  
Marcin Nobis
Keyword(s):  
Species Composition ◽  
Arid Zone ◽  
Field Studies ◽  
Vegetation Diversity ◽  
Plant Associations ◽  
Middle Asia ◽  
Recent Developments ◽  
Phytosociological Relevés ◽  
High Degree ◽  
Tian Shan

AbstractThis paper presents the results of phytosociological research on scree vegetation of the Pamir and south-western Tian Shan. We collected 222 phytosociological relevés during field studies conducted in 2015–2019, applying the Braun-Blanquet approach. We identified 21 plant communities on mobile and stabilized screes of colluvial cones, aprons and fans, inhabiting mainly the montane and alpine belts in several ranges (e.g. Peter the First, Alichur, Shugnan, Shachdarian, Darvaz, Rushan, Vanch, Fergana, Kyrgyz and Terskey ranges). As a result we provide the first comprehensive hierarchical syntaxonomic synopsis of scree communities at montane and alpine elevations in the eastern Middle Asia. The collected vegetation relevés represent the majority of the variation among the phytocoenoses of gravel, pebble, cobble and rock block slides and screes in the montane and alpine belts. As a result of field studies and Twinspan analyses, nine associations were identified on screes of the Pamir and western Tian Shan. All these communities were assigned to the Sileno brahuicae-Lactucetalia orientalis Nowak et al. 2021. Additionally, within the nitrophilous compact gravel screes one subassociation of Corydalidetum kashgaricae trigonelletosum gontscharovii was distinguished. In the most arid zone two additional plant associations and one subassociation were identified in gravelly semi-deserts zone. The main factors determining the species composition of the studied associations are scree mobility, rock particle size, elevation above sea level and slope inclination. Our research revealed considerable diversity of scree habitats of montane and alpine belts what might be astonishing regarding harsh environment of this mountainous territory. However, a great number of lineages that evolved here and particularly rich species pool of this habitat in Middle Asia facilitate remarkable diversity among vegetation of taluses and screes. The distinctiveness of species composition is additionally enhanced by high degree of endemism of chasmophytic habitats in the eastern part of Middle Asia. Despite recent developments, the prominent chasmophytic vegetation of Middle Asia still needs thorough studies focused on its relationship to semi-desert, tall-forb and petrophytic communities of high mountains of the Pamir, Hindu-Kush, Kunlun and Central Tian Shan.

scholarly journals Theology at Thresholds: Learning from a Practice ‘In Transition’

2017 ◽  
Vol 4 (1) ◽  
pp. 45-62 ◽  
Author(s):  
Rachel Muers ◽  
Rhiannon Grant
Keyword(s):  
Decision Making ◽  
The Other ◽  
Small Scale ◽  
Theological Ethics ◽  
Reciprocal Influence ◽  
Core Practices ◽  
Recent Developments ◽  
Collective Process ◽  
The One ◽  
Over Time

Recent developments in contemporary theology and theological ethics have directed academic attention to the interrelationships of theological claims, on the one hand, and core community-forming practices, on the other. This article considers the value for theology of attending to practice at the boundaries, the margins, or, as we prefer to express it, the threshold of a community’s institutional or liturgical life. We argue that marginal or threshold practices can offer insights into processes of theological change – and into the mediation between, and reciprocal influence of, ‘church’ and ‘world’. Our discussion focuses on an example from contemporary British Quakerism. ‘Threshing meetings’ are occasions at which an issue can be ‘threshed out’ as part of a collective process of decision-making. Drawing on a 2015 small-scale study (using a survey and focus group) of British Quaker attitudes to and experiences of threshing meetings, set in the wider context of Quaker tradition, we interpret these meetings as a space for working through – in context and over time – tensions within Quaker theology, practice and self-understandings, particularly those that emerge within, and in relation to, core practices of Quaker decision-making.

scholarly journals North Italy: Welcome to the Tropics!

2021 ◽  
Vol 13 (1) ◽  
pp. 215-218
Author(s):  
Federica Veronese ◽  
Francesca Graziola ◽  
Pamela Farinelli ◽  
Elisa Zavattaro ◽  
Vanessa Tarantino ◽  
...  
Keyword(s):  
High Temperatures ◽  
Climate Changes ◽  
Northern Italy ◽  
Larva Migrans ◽  
Cutaneous Larva Migrans ◽  
North East ◽  
The North ◽  
Caucasian Girl ◽  
The Tropics ◽  
High Degree

We describe a case of cutaneous Larva Migrans in an 8-year-old Caucasian girl. The lesion appeared ten days after a bath in the river in a valley in the north-east of Piedmont. The patient was successfully treated with Albendazole 400 mg daily for 5 days. Autochthonous cases are rare, particularly in northern Italy. Probably the high temperatures and the high degree of humidity favored by the climate changes to which Europe is subjected are favorable to the development of larvae. The diagnosis of cutaneous Larva Migrans should, therefore, be considered also in individuals who have not traveled in geographic areas at risk for the climate.

scholarly journals Shallow Water Bathymetry Inversion Using Hybrid Multi-band Composites Resulted from Integration of Drone-based RGB and Multispectral Imagery

2022 ◽  
Author(s):  
Evangelos Alevizos ◽  
Athanasios V Argyriou ◽  
Dimitris Oikonomou ◽  
Dimitrios D Alexakis
Keyword(s):  
Low Cost ◽  
Visible Spectrum ◽  
Small Scale ◽  
Multispectral Imagery ◽  
Depth Data ◽  
Recent Developments ◽  
Model Tuning ◽  
Inversion Techniques ◽  
Camera Sensors ◽  
Current Inversion

Shallow bathymetry inversion algorithms have long been applied in various types of remote sensing imagery with relative success. However, this approach requires that imagery with increased radiometric resolution in the visible spectrum is available. The recent developments in drones and camera sensors allow for testing current inversion techniques on new types of datasets. This study explores the bathymetric mapping capabilities of fused RGB and multispectral imagery, as an alternative to costly hyperspectral sensors. Combining drone-based RGB and multispectral imagery into a single cube dataset, provides the necessary radiometric detail for shallow bathymetry inversion applications. This technique is based on commercial and open-source software and does not require input of reference depth measurements in contrast to other approaches. The robustness of this method was tested on three different coastal sites with contrasting seafloor types. The use of suitable end-member spectra which are representative of the seafloor types of the study area and the sun zenith angle are important parameters in model tuning. The results of this study show good correlation (R2>0.7) and less than half a meter error when they are compared with sonar depth data. Consequently, integration of various drone-based imagery may be applied for producing centimetre resolution bathymetry maps at low cost for small-scale shallow areas.

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