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111.
Saleem Muhammad Hammad Potgieter Johan Arif Khalid Mahmood 《Precision Agriculture》2021,22(6):2053-2091
Precision Agriculture - Recently, agriculture has gained much attention regarding automation by artificial intelligence techniques and robotic systems. Particularly, with the advancements in... 相似文献
112.
Saleem Muhammad Hammad Potgieter Johan Arif Khalid Mahmood 《Precision Agriculture》2021,22(6):2092-2094
Precision Agriculture - A correction to this paper has been published: https://doi.org/10.1007/s11119-021-09824-9 相似文献
113.
Per-Erik Mellander Johan Bergh Tomas Lundmark Kevin Bishop 《European Journal of Forest Research》2008,127(1):71-79
Both aboveground and belowground climate affects net primary production (NNP) and forest growth. Little is known about how
above and belowground factors interact. The BIOMASS-model was tested to simulate photosynthetic recovery over a wide range
of soil temperatures created by snow cover manipulations on tree-scale plots in a 20-year-old Scots pine stand in northern
Sweden. The differences in timing of soil warming between the plots covered a span of two months. Carbon assimilation in needles,
sap flow, needle water potential and climatic parameters were measured in the field. The simulations revealed that an early
start of soil warming gave a relatively early photosynthetic recovery and a 7.5% increase of NPP. Late soil warming delayed
the photosynthetic recovery and reduced the NPP by 13.7%. This indicated that soil temperature needed to be accounted for,
as well as air temperature, when analysing photosynthetic recovery and NPP in boreal environment. The effects of differences
in soil temperature were reflected in the simulated photosynthetic recovery. The model did not fully capture the delay of
photosynthetic recovery caused by a late soil warming. It was possible to integrate the complexity of the soil climate effects
into a threshold date for soil thaw, using sapflow measurements together with information about air temperature and a day
degree sum, as long as water availability was not limiting water uptake by roots. Although a more realistic mechanism than
that currently in BIOMASS is desirable as climate change shifts the typical patterns of interplay between air and soil temperature
dynamics. 相似文献
114.
RAPD (randomly amplified polymorphic DNA) analyses were carried out on 21 accessions of Lachenalia bulbifera (Cyrillo) Engl. Five pre-selected primers produced an average of 88% polymorphisms. Fifteen of the 21 accessions could be
identified using the five primers. In a pairwise comparison genetic distance values ranging from 0.11 to 1.08 were obtained.
These values reveal a high amount of variation within the species. The genetic distance values within the tetraploid and hexaploid
groups on the south coast were low, but values were high between the groups on the south coast and those on the west coast.
A dendogram was constructed from the RAPD banding profiles, using UPGM cluster analysis. The dendogram clusters certain accessions
together. These clusters are supported by their geographical locality and chromosome data. The hexaploid group, tetraploid
group and octoploid group on the south coast are respectively clustered together. It is concluded that RAPDs can be used to
assess the genetic variation at an intra-specific level in Lachenalia.
This revised version was published online in July 2006 with corrections to the Cover Date. 相似文献
115.
Valeria Villanova Christian Galasso Giovanni Andrea Vitale Gerardo Della Sala Johan Engelbrektsson Niklas Strmberg Kashif Mohd Shaikh Mats X. Andersson Fortunato Palma Esposito Susanne Ekendahl Donatella De Pascale Cornelia Spetea 《Marine drugs》2022,20(7)
A local strain of Nannochloropsis granulata (Ng) has been reported as the most productive microalgal strain in terms of both biomass yield and lipid content when cultivated in photobioreactors that simulate the light and temperature conditions during the summer on the west coast of Sweden. To further increase the biomass and the biotechnological potential of this strain in these conditions, mixotrophic growth (i.e., the simultaneous use of photosynthesis and respiration) with glycerol as an external carbon source was investigated in this study and compared with phototrophic growth that made use of air enriched with 1–2% CO2. The addition of either glycerol or CO2-enriched air stimulated the growth of Ng and theproduction of high-value long-chain polyunsaturated fatty acids (EPA) as well as the carotenoid canthaxanthin. Bioassays in human prostate cell lines indicated the highest antitumoral activity for Ng extracts and fractions from mixotrophic conditions. Metabolomics detected betaine lipids specifically in the bioactive fractions, suggesting their involvement in the observed antitumoral effect. Genes related to autophagy were found to be upregulated by the most bioactive fraction, suggesting a possible therapeutic target against prostate cancer progression. Taken together, our results suggest that the local Ng strain can be cultivated mixotrophically in summer conditions on the west coast of Sweden for the production of high-value biomass containing antiproliferative compounds, carotenoids, and EPA. 相似文献
116.
The selective fungitoxic actions of prochloraz (an imidazole) and a triazole fungicide, quinconazole (3-(2,4-dichlorophenyl)-2-(1 H- 1,2,4-triazol-1-yl)- 4(3H)-quinazolinone: II ), were studied with selected phytopathogenic fungi. With the exception of Ustilago maydis, all the fungi tested were more sensitive to prochloraz than to II. A number of DMI-resistant mutants of Penicillium digitatum and P. italicum showed positive cross-resistance to both DMIs, but except for P. italicum isolate H17, the levels of resistance to II were much higher than to prochloraz. The generally higher toxicity of prochloraz to the fungi investigated, as compared to II , could not be ascribed to the slightly higher accumulation of prochloraz. With regard to prochloraz, there was no general correlation between the sensitivity of the fungi tested and the amount of fungicide accumulated. A similar situation was evident for II. However, the DMI-resistant mutants of P. italicum did show a reduced accumulation of both azoles, which may account for a low level of acquired DMI-resistance in this fungus. Since accumulation levels of the test compounds in the isolates with different degrees of resistance were the same, additional mechanisms of resistance may be involved in isolates with relatively high degrees of DMI-resistance. No detectable amounts of fungicide metabolites were found in most fungi tested over a 16-hour incubation period. Therefore, fungal metabolism is not generally responsible for the differences in sensitivity between fungi to each azole tested. It also does not generally explain the differential toxicities of prochloraz and II to each individual species. The exception to this was Rhizoctonia solani which metabolized prochloraz to a non-fungitoxic compound. This correlated with its low prochloraz sensitivity. 相似文献
117.
118.
Seventeen Sustainable Development Goals (SDGs) were adopted by 193 Governments at the General Assembly of the United Nations in 2015 for achievement by 2030. These SDGs present a roadmap to a sustainable future and a challenge to the science community. To guide activities and check progress, targets and indicators have been and are still being defined. The soil science community has published documents that describe the primary importance of soil for SDGs addressing hunger, water quality, climate mitigation and biodiversity preservation, and secondary relevance of soil for addressing several other SDGs. Soil scientists only marginally participated in the SDG discussions and are currently only peripherally engaged in discussions on targets or indicators. Agreement on several soil‐related indicators has still not been achieved. Involvement of soil scientists in SDG‐based studies is desirable for both developing solutions and increasing the visibility of the soil profession. Inputs into policy decisions should be improved as SDG committee members are appointed by Governments. Possible contributions of soil science in defining indicators for the SDGs are explored in this paper. We advocate the pragmatic use of soil–water–atmosphere–plant simulation models and available soil surveys and soil databases where “representative” soil profiles for mapping units (genetically defined genoforms) are functionally expressed in terms of several phenoforms reflecting effects of different types of soil use and management that strongly affect functionality. 相似文献
119.
Johan Bouma 《Soil Use and Management》2019,35(1):32-38
Soil use and management play a key role, when maintaining or restoring soil quality, as an estimated 30% of soils in the world suffer from various forms of degradation. Several of the seventeen UN Sustainable Development Goals (SDGs), approved in 2015 by 195 governments, are land‐related, providing a stimulating challenge for soil research. Unfortunately, soil degradation is still prominent, even though decades of research have resulted in restorative and innovative forms of soil management, generating successful case studies all over the world. Why don't enough farmers adopt such research results? Some argue that the problem of soil degradation is mainly socio‐economic rather than technical. However, this is not correct as the soil–water–plant–climate system raises many basic, unresolved questions about soil behaviour. More attention is needed for information sharing and knowledge building to link the research arena with stakeholders and policy makers. This is particularly urgent because the information revolution, which is fundamentally changing attitudes of increasingly critical stakeholders, presents a challenge to distinguish between relevant and irrelevant information on Internet and social media. Continuous interaction with land users in the field and sharing knowledge in a joint‐learning mode is needed more than ever, recognizing that different forms of knowledge can contribute to acceptance in the practice of land‐use innovations and lead to realization of land‐related SDGs. Such forms of interaction take much time, which is of limited availability in current research regimes, and implies a need for change. Soil scientists need assistance from communication experts to facilitate interaction processes. 相似文献
120.
Johan Sakshaug 《Acta veterinaria Scandinavica》1965,6(1):112
The acute, oral toxicity of fenthion (O,O-dimethyl-O-(3-methyl-4-methylmercapto-phenyl)thiophosphate) in different formulations emulgated in water was studied. For male, white rats the approximate values for LD50 found varied from 340 to 560 mg per kg, technical fenthion in commercial products being more toxic than the chemically pure compound. Fenthion in the commercial preparation Lebaycid was more toxic for male, white mice (LD50 approx. 125 mg per kg) than for rats. 相似文献