Ecological and Genetic Systems Underlying Sustainable Horticulture

2010 ◽  
pp. 331-362 ◽  
Author(s):  
Autar K. Mattoo ◽  
John R. Teasdale
2015 ◽  
Vol 41 (1) ◽  
pp. 57
Author(s):  
Juan WEN ◽  
Jian-Feng XU ◽  
Yan LONG ◽  
Hai-Ming XU ◽  
Jin-Ling MENG ◽  
...  

Life ◽  
2021 ◽  
Vol 11 (4) ◽  
pp. 271
Author(s):  
Chentao Yong ◽  
Andras Gyorgy

While the vision of synthetic biology is to create complex genetic systems in a rational fashion, system-level behaviors are often perplexing due to the context-dependent dynamics of modules. One major source of context-dependence emerges due to the limited availability of shared resources, coupling the behavior of disconnected components. Motivated by the ubiquitous role of toggle switches in genetic circuits ranging from controlling cell fate differentiation to optimizing cellular performance, here we reveal how their fundamental dynamic properties are affected by competition for scarce resources. Combining a mechanistic model with nullcline-based stability analysis and potential landscape-based robustness analysis, we uncover not only the detrimental impacts of resource competition, but also how the unbalancedness of the switch further exacerbates them. While in general both of these factors undermine the performance of the switch (by pushing the dynamics toward monostability and increased sensitivity to noise), we also demonstrate that some of the unwanted effects can be alleviated by strategically optimized resource competition. Our results provide explicit guidelines for the context-aware rational design of toggle switches to mitigate our reliance on lengthy and expensive trial-and-error processes, and can be seamlessly integrated into the computer-aided synthesis of complex genetic systems.


Genetics ◽  
1998 ◽  
Vol 148 (3) ◽  
pp. 1333-1340 ◽  
Author(s):  
Hong-Wen Deng ◽  
Yun-Xin Fu

AbstractThe past decades have witnessed extensive efforts to correlate fitness traits with genomic heterozygosity. While positive correlations are revealed in most of the organisms studied, results of no/negative correlations are not uncommon. There has been little effort to reveal the genetic causes of these negative correlations. The positive correlations are regarded either as evidence for functional overdominance in large, randomly mating populations at equilibrium, or the results of populations at disequilibrium under dominance. More often, the positive correlations are viewed as a phenomenon of heterosis, so that it cannot possibly occur under within-locus additive allelic effects. Here we give exact genetic conditions that give rise to positive and negative correlations in populations at Hardy-Weinberg and linkage equilibria, thus offering a genetic explanation for the observed negative correlations. Our results demonstrate that the above interpretations concerning the positive correlations are not complete or even necessary. Such a positive correlation can result under dominance and potentially under additivity, even in populations where associated overdominance due to linked alleles at different loci is not significant. Additionally, negative correlations and heterosis can co-occur in a single population. Although our emphasis is on equilibrium populations and for biallelic genetic systems, the basic conclusions are generalized to non-equilibrium populations and for multi-allelic situations.


2021 ◽  
pp. 2000252
Author(s):  
Yang Zhang ◽  
Wentao Ding ◽  
Zhihui Wang ◽  
Huimin Zhao ◽  
Shuobo Shi

1993 ◽  
Vol 9 (10) ◽  
pp. 392-395 ◽  
Author(s):  
L.D. Sibley ◽  
E.R. Pfefferkorn ◽  
J.C. Boothroyd

2021 ◽  
Vol 13 (15) ◽  
pp. 8532
Author(s):  
Michael M. Blanke ◽  
Sabine D. Golombek

(1) Background: Black plastics pose a general problem in sustainability issues, as the recycling is hampered by the black colour disguising the type of plastics in the NIR scanner on the garbage sorting belt, as the black colour absorbs NIR radiation. Sorting flower/plant pots suffer from their additional soil contamination in the strive for sustainable flower production in horticulture. As these black plastic flowerpots are currently rarely recycled, a study was instigated of reusing them based on Heino Schwarz’s innovative idea. (2) Methods: In the first step, the carbon footprint was calculated for the flowerpots of two sizes employed in the nursery, their customised production from virgin polypropylene and the delivery from the Netherlands to the nursery in Bavaria. In step 2, the carbon footprint was calculated based on PAS 2050-1 for the number of flowerpots in circulation and return rates in 2019 and in 2020 to assess the GHG saved by the innovation. (3) Results: The innovative concept of Heino Schwarz is a discount on returning the customised used flowerpots, with a 40% increase from 24,533 returned flowerpots in 2019 to 39,797 in 2020. This shows the increasing acceptance and environmental awareness of the consumer and the great success. (4) Conclusions and outlook: The present case study has shown that innovative approaches such as discounts for reused/returned flowerpots of the Schwarz nursery can save 3.85–4.56 t CO2eq, a valuable contribution to reducing GHG emissions, creating environmental awareness among the consumers and building a close B2C relationship. The amount of CO2eq saved is equivalent to ca. 40% of the annual carbon burden of a European/German citizen or ca. 23,000 km driven in a private vehicle, the average mileage driven privately in two years.


1977 ◽  
Vol 26 (1) ◽  
pp. 81-82 ◽  
Author(s):  
Steve Selvin

A definition of efficiency is presented to aid a researcher in the choice of the genetic systems for the diagnosis of twin zygosity. An expression is given that produces a numeric value that indicates which systems do the most effective job of discriminating DZ twins from a sample of twin pairs. This definition of efficiency is illustrated with eight blood groups commonly used in twin zygosity diagnosis.


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