Plant Volatiles-based Insect Pest Management in Organic Farming

Organic agriculture is increasing in popularity worldwide due to the rapidly growing market for organic products. In organic production, insects present a major pest challenge that negatively impacts crop health and yield. To successfully manage an organic farmland, an effective insect pest management program is key. In this review, we first describe the approaches currently used for pest management in organic farming. Next, we review natural plant defense mechanisms, especially those based on plant volatile organic compounds. Chemically complex, plant volatiles have multiple ecological roles in plant-insect interactions including attracting pollinators, acting as cues for foraging herbivores as well as functioning as direct defense, indirect defense, or interplant priming. Based on the ecological roles of plant volatiles, we then discuss in-depth how pest management may be improved through a variety of strategies including using resistant cultivars, polyculture, using beneficial microorganisms such as mycorrhizal fungi and endophytes, and using plant-derived pesticides, all of which are reviewed in the context of plant volatiles. Lastly, integration of these different strategies based on the trait of plant volatiles for a successful and sustainable pest management program in organic farming is discussed.     

Unusual P450 reactions in plant secondary metabolism

Plant cytochromes P450 (P450s) participate in a variety of biochemical pathways to produce a vast diversity of plant natural products. The number of P450 genes in plant genomes is estimated to be up to 1% of the total gene annotations of each plant species, implying that plants are huge sources for various P450-dependent reactions. Plant P450s catalyze a wide variety of monooxygenation/hydroxylation reactions in secondary metabolism, and some of them are involved in unusual reactions such as methylenedioxy-bridge formation, phenol coupling reactions, oxidative rearrangement of carbon skeletons, and oxidative C–C bond cleavage. Here, we summarize unusual P450 reactions in various plant secondary metabolisms, and describe their proposed reaction mechanisms.     

More years of field trials against Plasmopara viticola in organic viticolture

The organic viticulture assumes a decisive role in the national agricultural sector. More impelling problems in the management of organic vineyards are represented from the plants pathology defence and particularly of Plasmopara viticola containment. Copper represents one of the few usable fungicides in the organic farming and the only effective against downy mildew. With Regulation EC n. 473/2002, fixed maximum quantity usable of copper compounds, owing to the environment problems due to the copper accumulation in the soil. To reduce quantity of metal copper or replace it with natural products, are conducted field trials with copper compounds at a low rate or alternative to copper products. Besides, we are estimating possibility to reduce the operations against P. viticola optimizing fungicidal treatments. Field trials in the organic farms located near Rome, have been carried out. Guidelines EPPO/OEPP PP 1/31 (3) have been carried out. The results of the trials have showed that, using cupric products with low metallic content, to reduce copper quantities used, always allowed to respect the limits established by Regulation EC. The alternative products that were investigated have not guaranteed, instead, an adequate protection in high pressure of grapevine downy mildew. It was possible to reduce treatments against P. viticola through control of different environmental parameters. The trials confirm that the copper is indispensable for plant protection in organic farming as it is not possible to replace it with natural extracts substances. We can reduce, instead, the copper quantities used trough the use of new products with low quantity metal copper or through the evaluation of climatic and pedologic data that allow to rationalize the fungicidal treatments.     

Tobacco,a highly efficient green bioreactor for production of therapeutic proteins

Molecular farming of pharmaceuticals in plants has the potential to provide almost unlimited amounts of recombinant proteins for use in disease diagnosis, prevention or treatment. Tobacco has been and will continue to be a major crop for molecular farming and offers several practical advantages over other crops. It produces significant leaf biomass, has high soluble protein content and is a non-food crop, minimizing the risk of food-chain contamination. This, combined with its flexibility and highly-efficient genetic transformation/regeneration, has made tobacco particularly well suited for plant-based production of biopharmaceutical products. The goal of this review is to provide an update on the use of tobacco for molecular farming of biopharmaceuticals as well the technologies developed to enhance protein production/purification/efficacy. We show that tobacco is a robust biological reactor with a multitude of applications and may hold the key to success in plant molecular farming.     

Grassland butterflies and low intensity farming in Europe

In this paper we describe the impact of the abandonment of traditional farming practices on butterflies and their habitats in traditional, often montane, pastoral systems. We link these declines to socioeconomic factors: illustrating how the failure of the CAP to support traditional farming leads to structural changes in farming enterprises??features which may be obscured by crude statistics on stock. We then call for the scheduled CAP reforms in 2013 to be radically realigned to support rather than destroy biodiversity so that any new EU agri-biodiversity commitments have an effective funding stream to support them.     

Plants as bioreactors: a comparative study suggests that Medicago truncatula is a promising production system

Plants are emerging as a promising alternative to conventional platforms for the large-scale production of recombinant proteins. This field of research, known as molecular farming, is developing rapidly and several plant-derived recombinant proteins are already in advanced clinical trials. However, the full potential of molecular farming can only be realized if we gain a fundamental understanding of biological processes regulating the production and accumulation of functional recombinant proteins in plants. Recent studies indicate that species- and tissue-specific factors as well as plant physiology can have a significant impact on the amount and quality of the recombinant product. More detailed comparative studies are needed for each product, including the analysis of expression levels, biochemical properties, in vitro activity and subcellular localization. In this review we include the first results from an extensive comparative study in which the highly glycosylated enzyme phytase (from the fungus Aspergillus niger) was produced in different plant species (including tobacco and the model legume Medicago truncatula). Special emphasis is placed on M. truncatula, whose leaves accumulated the highest levels of active phytase. We discuss the potential of this species as a novel production host.     

Plant Cytochrome P450 Monooxygenases

Plant systems utilize a diverse array of cytochrome P450 monooxygenases (P450s) in their biosynthetic and detoxification pathways. The classic forms of these enzymes are heme-dependent mixed function oxidases that utilize NADPH or NADH and molecular oxygen to produce functionalized organic products. The nonclassical forms are monooxygenases that either do not utilize flavoproteins for dioxygen activation or fail to incorporate molecular oxygen into their final product. Biosynthetic P450s play paramount roles in the synthesis of lignin intermediates, sterols, terpenes, flavonoids, isoflavonoids, furanocoumarins, and a variety of other secondary plant products. Other catabolic P450s metabolize toxic herbicides and insecticides into nontoxic products or, conversely, activate nontoxic substances into toxic products. Biochemical and molecular characterizations on a number of plant P450s have indicated that the relationships between these heme proteins and their substrates are at least as complex as those that exist in mammalian systems. Examples now exist of plant P450s that metabolize: a narrow range of substrates to yield different products, a single substrate to yield different products, multiple substrates to yield the same product, or a single substrate sequentially to yield discrete intermediates in the biosynthesis of a single product. Extensive divergence of catalytic site as well as noncatalytic site residues accounts for the high degree of primary structure variation in the P450 gene superfamily and the diverse array of substrates synthesized and/or detoxified by these proteins. Classic P450s still retain a highly conserved F-G-R-C-G motif in their catalytic site and conserved amino acids in their oxygen binding pocket; nonclassical P450s diverge at several of these positions. A broad range of cloning and transient expression strategies are suitable for plant P450 studies and these have allowed for the isolation and characterization of a number of P450 cDNAs and genes. Because many of these sequences have been cloned only recently, much remains to be learned about the substrate specificities of P450 reactions in plants and the mechanisms by which their genes are regulated.     

Linkage disequilibrium and association studies in higher plants: Present status and future prospects

During the last two decades, DNA-based molecular markers have been extensively utilized for a variety of studies in both plant and animal systems. One of the major uses of these markers is the construction of genome-wide molecular maps and the genetic analysis of simple and complex traits. However, these studies are generally based on linkage analysis in mapping populations, thus placing serious limitations in using molecular markers for genetic analysis in a variety of plant systems. Therefore, alternative approaches have been suggested, and one of these approaches makes use of linkage disequilibrium (LD)-based association analysis. Although this approach of association analysis has already been used for studies on genetics of complex traits (including different diseases) in humans, its use in plants has just started. In the present review, we first define and distinguish between LD and association mapping, and then briefly describe various measures of LD and the two methods of its depiction. We then give a list of different factors that affect LD without discussing them, and also discuss the current issues of LD research in plants. Later, we also describe the various uses of LD in plant genomics research and summarize the present status of LD research in different plant genomes. In the end, we discuss briefly the future prospects of LD research in plants, and give a list of softwares that are useful in LD research, which is available as electronic supplementary material (ESM) Electronic supplementary material Electronic supplementary material is available for this article at and accessible for authorised users.     

Strategies and agronomic interventions to improve the phosphorus-use efficiency of farming systems

Phosphorus (P)-deficiency is a significant challenge for agricultural productivity on many highly P-sorbing weathered and tropical soils throughout the world. On these soils it can be necessary to apply up to five-fold more P as fertiliser than is exported in products. Given the finite nature of global P resources, it is important that such inefficiencies be addressed. For low P-sorbing soils, P-efficient farming systems will also assist attempts to reduce pollution associated with P losses to the environment. P-balance inefficiency of farms is associated with loss of P in erosion, runoff or leaching, uneven dispersal of animal excreta, and accumulation of P as sparingly-available phosphate and organic P in the soil. In many cases it is possible to minimise P losses in runoff or erosion. Uneven dispersal of P in excreta typically amounts to ~5% of P-fertiliser inputs. However, the rate of P accumulation in moderate to highly P-sorbing soils is a major contributor to inefficient P-fertiliser use. We discuss the causal edaphic, plant and microbial factors in the context of soil P management, P cycling and productivity goals of farms. Management interventions that can alter P-use efficiency are explored, including better targeted P-fertiliser use, organic amendments, removing other constraints to yield, zone management, use of plants with low critical-P requirements, and modified farming systems. Higher productivity in low-P soils, or lower P inputs in fertilised agricultural systems can be achieved by various interventions, but it is also critically important to understand the agroecology of plant P nutrition within farming systems for improvements in P-use efficiency to be realised.     

Time to articulate a vision for the future of plant proteomics - A global perspective: An initiative for establishing the International Plant Proteomics Organization (INPPO)

Given the essential role of proteomics in understanding the biology of plants, we are establishing a global plant proteomics organization to properly organize, preserve and disseminate collected information on plant proteomics. We call this organization 'International Plant Proteomics Organization (INPPO; http://www.inppo.com).' Ten initiatives of INPPO are outlined along with how to address them in multiple phases. As our vision is global, we sincerely hope the scientific communities around the world will come together to support and join INPPO.