The plasticity of root architecture is crucial for plants to acclimate unfavorable environments including low nitrogen (LN) stress. How maize roots coordinate the growth of axile roots and lateral roots (LRs), as well as longitudinal and radial cell behaviours in response to LN stress remains unclear. Maize plants were cultivated hydroponically under control (4 mM nitrate) and LN (40 μM) conditions. Temporal and spatial samples were taken to analyse changes in the morphology, anatomical structure, and carbon/nitrogen (C/N) ratio in the axile and lateral roots. LN stress increased axile root elongation, reduced the number of crown roots, and decreased LR density and length. LN extended cell elongation zones and increased the mature cell length in the roots. LN reduced the cell diameter and total area of vessels and increased the amount of aerenchyma, but the number of cell layers in the crown root cortex was unchanged. The C/N ratio was higher in axile roots than in LRs. Maize roots acclimate to LN by optimizing the anatomical structure and N allocation. As a result axile root elongation is favored to efficiently find available N in the soil.
I think this is a great story - here's a video from 2009 showing an expedition to find natural enemies of the invasive plant Himalayan balsam, and today the rust fungus (after years of study and testing) is being released in an effort to combat it.
I just stumbled across one of these and wanted to share the link - published by the Ecological Society of America, and written for the general public / high school / university undergraduates. Topics include biofuels, nitrogen in the environment, climate change.
Despite the many challenges in detecting and functionally characterizing small molecules, genomics advances paired with increasingly sophisticated metabolomics approaches have led to a steady increase in the discovery of metabolites of diverse structure and roles in signaling and regulatory processes. This special issue will highlight recent advances and discoveries in the field of small molecule research ranging from signaling metabolites in primary metabolism to molecules with roles in inter- or intra-specific interactions in plants and algae. The reader will find traditional functional classifications of small molecules to become increasingly blurred since many chemicals act as exogenous signals and simultaneously serve important endogenous functions in plant physiology and development.
"A balanced assessment of ecosystem services provided by agriculture requires a systems-level socioecological understanding of related management practices at local to landscape scales. The results from 25 years of observation and experimentation at the Kellogg Biological Station long-term ecological research site reveal services that could be provided by intensive row-crop ecosystems. In addition to high yields, farms could be readily managed to contribute clean water, biocontrol and other biodiversity benefits, climate stabilization, and long-term soil fertility, thereby helping meet society's need for agriculture that is economically and environmentally sustainable. "
Mary Williams's insight:
Good resource for students interested in the environmental footprint of various agricultural strategies
" Following repeated kicks in the same direction, goalkeepers became increasingly likely to dive in the opposite direction on the next kick. Surprisingly, kickers failed to exploit these goalkeeper biases. Our findings highlight the importance of monitoring and predicting sequential behavior in real-world competition. "
• Premise of the study: Reaction wood (RW) in seed plants can induce late and usually secondary changes in organ orientation. Conifers produce compression wood (CW), generated by compression tracheids, which generate a push force. Angiosperms produce tension wood (TW), generated by tension wood fibers (TWF) often described as “gelatinous fibers,” which exert a pull force. Usually RW is produced eccentrically, but it can occur concentrically, as in aerial roots of Ficus. However, gymnosperms can produce gelatinous fibers (tension fibers, TF), as in cortical and secondary phloem tissues (Gnetum). TFs are therefore limited neither to wood, xylem, nor angiosperms. Here we demonstrate that TFs in secondary phloem are involved in contraction of roots of cycads and compare them with TFs of Ficus.
• Methods: We sectioned root material of cycads at various stages of seedling development using simple staining and histochemical procedures to follow the course of secondary phloem development. Aerial roots of Ficus were compared with the cycad root material.
• Key results: Tension fibers (gelatinous fibers) occur extensively and continuously in the secondary phloem in roots that undergo contraction. Older tissues, but notably the xylem, become distorted by contraction. TFs in cycads correspond in cell wall features to TFs that occur in Ficus, but do not occur in secondary xylem. The individual fibers visibly contract.
• Conclusions: Tissue contraction in Cycas and Zamia corresponds to that found in angiosperms and Gnetum and further broadens the scope of the activity of tension tissues. This finding possibly indicates that gelatinous fibers originated at a very early period of seed plant evolution.
The only concern I have is about the first sentence of the abstract - "WHEN humans will settle on the moon or Mars they will have to eat there". Personally, I'd rather we put our energy into keeping earth habitable, thank you!
This paper exploreswhether crop genetic engineering can contribute to addressing food security, as well as enhancing human nutrition and farming under a changing climate.
The review is based on peer-refereed literature, using results to determine the potential of this gene technology. It also provides a brief summary of issues surrounding this genetic enhancement approach to plant breeding, and the impacts on farming, livelihoods, and the environment achieved so far.
The genetic engineering pipeline looks promising, particularly for adapting more nutritious, input-efficient crops in the development of the world’s farming systems...
Although the technologies demonstrate potential to reduce crop losses, food waste, and enhance nutritional quality... farmers’ surveys reveal that increased yields are among the benefits for growing transgenic crops. Such a finding results from yield increases because of reduced losses from insect pests and weeds. In most developing countries, crop yields are low and yield gaps are large because of low input use, poor soil health, and pests and diseases.
Genetic engineering has a lot promise in increasing overall adaptive capacity of agriculture but emphasis on good agricultural practices, including maintenance of soil, water, and genetic resources and increasing irrigation and fertilizers remains critical to increasing production...
Given that current trends in yield increase are insufficient to double food production by 2050 and keep up with population and shifting consumption patterns, new approaches to the problem are needed. Transgenic cultivars could be a piece of that puzzle, building on success stories such as that of WEMA, but it is crucial that safety concerns are adequately addressed.
Further research should benchmark conventional approaches to crop improvement, compare them with likely yield increases available from transgenic approaches, and explicitly address climate impacts to ascertain the true potential of transgenic technologies in adapting to and mitigating climate change in the long term.
"Non-tenure-track—also known as adjunct or contingent—faculty members now make up more than 70 percent of those who teach in higher education. The trend—which shows little sign of abating—threatens national goals of maintaining global preeminence in science and technology, including biology, say education experts. "
Filamentous pathogens pose a substantial threat to global food security. One central question in plant pathology is how pathogens cause infection and manage to evade or suppress plant immunity to promote disease. With many technological advances over the past decade, including DNA sequencing technology, an array of new tools has become embedded within the toolbox of next-generation plant pathologists. By employing a multidisciplinary approach plant pathologists can fully leverage these technical advances to answer key questions in plant pathology, aimed at achieving global food security. This review discusses the impact of: cell biology and genetics on progressing our understanding of infection structure formation on the leaf surface; biochemical and molecular analysis to study how pathogens subdue plant immunity and manipulate plant processes through effectors; genomics and DNA sequencing technologies on all areas of plant pathology; and new forms of collaboration on accelerating exploitation of big data. As we embark on the next phase in plant pathology, the integration of systems biology promises to provide a holistic perspective of plant–pathogen interactions from big data and only once we fully appreciate these complexities can we design truly sustainable solutions to preserve our resources.
Potassium (K+) is one of the most abundant elements of soil composition but its very low availability limits plant growth and productivity of ecosystems. Because this cation participates in many biological processes, its constitutive uptake from soil solution is crucial for the plant cell machinery. Thus, the understanding of strategies responsible of K+ nutrition is a major issue in plant science. Mycorrhizal associations occurring between roots and hyphae of underground fungi improve hydro-mineral nutrition of the majority of terrestrial plants. The contribution of this mutualistic symbiosis to the enhancement of plant K+ nutrition is not well understood and poorly studied so far. This mini-review examines the current knowledge about the impact of both arbuscular mycorrhizal and ectomycorrhizal symbioses on the transfer of K+ from the soil to the plants. A model summarizing plant and fungal transport systems identified and hypothetically involved in K+ transport is proposed. In addition, some data related to benefits for plants provided by the improvement of K+ nutrition thanks to mycorrhizal symbioses are presented.
When it comes to preventing disease damage to crops, time is of the essence – but so is accuracy. This is why growers and crop experts need better means to accurately diagnose diseases and identify causal agents in the field without having to wait several days for laboratory results.