Almendro en flor

Vincent van Gogh

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Legumes versus rhizobia: a model for ongoing conflict in symbiosis 
Joel L. Sachs Kenjiro W. Quides Camille E. Wendlandt

The legume–rhizobia association is a powerful model of the limits of host control over microbes. Legumes regulate the formation of root nodules that house nitrogen‐fixing rhizobia and adjust investment into nodule development and growth. However, the range of fitness outcomes in these traits reveals intense conflicts of interest between the partners. New work that we review and synthesize here shows that legumes have evolved varied mechanisms of control over symbionts, but that host control is often subverted by rhizobia. An outcome of this conflict is that both legumes and rhizobia have evolved numerous traits that can improve their own short‐term fitness in this interaction, but little evidence exists for any net improvement in the joint trait of nitrogen fixation.

Legume and rhizobia conflict over nodule number. (a) Costs vs benefits of nodulation are modeled. Plant costs to nodulation (carbon, C) are predicted to be a linear function of the number of nodules formed (Nod#) with a slope of m (cost per nodule): f{C} = m × Nod#. Plant benefits from nodulation (nitrogen, N) are predicted to be a negative exponential function, f{N} = α(1 − e^(B×Nod#)), with diminishing returns that reach an asymptote at α and diminish at a rate corresponding to B. (b) Net benefits of nodulation can be calculated by subtracting the cost from the benefit functions. The net benefit function for nodulation is unimodal, increasing with the formation of nodules (zone of cooperation) until the optimal number of nodules is reached (N–C^(max)), and above which additional nodules reduce the host benefit (zone of conflict). If too few or too many nodules are formed, the host does not acquire the net minimal benefit to set seed (i.e. < N–C^(min)). (c) Host fitness (i.e. growth, seed set) varies with the number of nodules formed. Lotus japonicus mutants have been generated that form too many nodules compared with wild‐type and thus experience reduced fitness.
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https://nph.onlinelibrary.wiley.com/doi/10.1111/nph.15222
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1971 - The Lorax - Dr. Seuss.pdf by alihhj on Scribd

https://www.theguardian.com/books/2018/jul/23/dr-seuss-lorax-inspired-by-orange-kenyan-monkeys?CMP=share_btn_tw 

https://www.nature.com/articles/s41559-018-0628-x
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Slimemolds 
Photo: @bealeiderman
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Evidence that organic farming promotes pest control      

Lucile Muneret, Matthew Mitchell, Verena Seufert, Stéphanie Aviron, El Aziz Djoudi, Julien Pétillon, Manuel Plantegenest, Denis Thiéry & Adrien Rusch

Ecological intensification of agro-ecosystems, based on the optimization of ecological functions such as biological pest control, to replace agrochemical inputs is a promising route to reduce the ecological footprint of agriculture while maintaining commodity production. However, the performance of organic farming, often considered as a prototype of ecological intensification, in terms of pest control remains largely unknown. Here, using two distinct meta-analyses, we demonstrate that, compared to conventional cropping systems, (i) organic farming promotes overall biological pest control potential, (ii) organic farming has higher levels of overall pest infestations but (iii) that this effect strongly depends on the pest type. Our study shows that there are lower levels of pathogen infestation, similar levels of animal pest infestation and much higher levels of weed infestation in organic than in conventional systems. This study provides evidence that organic farming can enhance pest control and suggests that organic farming offers a way to reduce the use of synthetic pesticide for the management of animal pests and pathogens without increasing their levels of infestation.

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https://www.nature.com/articles/s41893-018-0102-4.epdf?author_access_token=vz2NiLiAJWq8p6Kq8COozdRgN0jAjWel9jnR3ZoTv0Og-b_ymdoFUCQ2kyUf73zy7SGA7_RjBaetKoG-OtYIHKebdz4fBH8STW-VbQ8dN_90dd8hhdBsOApRNFaoYdfKQwJMB8rvKheBe6jGfTN33A%3D%3D
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http://www.agroecologia2018.com/
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Levon Biss 
http://www.thisiscolossal.com/2018/07/microsculpture-by-levon-biss/
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Lewontin & Levins - Biology Under the Influence Dialectical Essays on Ecology, Agriculture, And Health by Felipe Mercado Sandy on Scribd

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A female personification of the continent America, engraved by  Adriaen Collaert(ca. 1590)
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"...there is something sad, and indeed ominous, about the direction of America’s gaze – turned away from the traditional life of hunting (and roasting human meat) depicted on the left, toward the mass bloodshed and slaughter brought about by the arrival of the Spanish depicted on the right" 
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https://publicdomainreview.org/collections/america-a-personification-ca-1590/
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