Search

Current crop protection chemicals span an array of chemistry classes and modes of action. Typically, within each chemistry class, there are multiple chemically distinct active ingredients competing with each other for market position. In this competition, the first product to market in a new class or mode of action may or may not have an advantage depending upon a number of parameters, including relative efficacy against the target pests, pest resistance, regulatory pressures, synthetic complexity, and marketing effectiveness. The number of companies involved in the discovery of new crop protection compounds has been declining, and patenting strategies have become more sophisticated, making it more challenging to break into an existing area of chemistry. One result is new classes of chemistry tend to be smaller, making first to market more beneficial than in the past. Additionally, the first into a market with a new class of chemistry has the opportunity to set positioning and expectations.

Understanding the reasons for overuse of agricultural chemicals is critical to the sustainable development of Chinese agriculture. Using a nationally representative rural household survey from China, we found that farm size is a strong factor that affects the use intensity of agricultural chemicals across farms in China. Statistically, a 1% increase in farm size is associated with a 0.3% and 0.5% decrease in fertilizer and pesticide use per hectare ( P < 0.001), respectively, and an almost 1% increase in agricultural labor productivity, while it only leads to a statistically insignificant 0.02% decrease in crop yields. The same pattern was also found using other independently collected data sources from China and an international panel analysis of 74 countries from the 1960s to the 2000s. While economic growth has been associated with increasing farm size in many other countries, in China this relationship has been distorted by land and migration policies, leading to the persistence of small farm size in China. Removing these distortions would decrease agricultural chemical use by 30-50% and the environmental impact of those chemicals by 50% while doubling the total income of all farmers including those who move to urban areas. Removing policy distortions is also likely to complement other remedies to the overuse problem, such as easing farmer's access to modern technologies and knowledge, and improving environmental regulation and enforcement., Competing Interests: The authors declare no conflict of interest., (Copyright © 2018 the Author(s). Published by PNAS.)

Glycolipids, consisting of a carbohydrate moiety linked to fatty acids, are microbial surface active compounds produced by various microorganisms. They are characterized by high structural diversity and have the ability to decrease the surface and interfacial tension at the surface and interface, respectively. Rhamnolipids, trehalolipids, mannosylerythritol lipids and cellobiose lipids are among the most popular glycolipids. They have received much practical attention as biopesticides for controlling plant diseases and protecting stored products. As a result of their antifungal activity towards phytopathogenic fungi and larvicidal and mosquitocidal potencies, glycolipid biosurfactants permit the preservation of plants and plant crops from pest invasion. Also, as a result of their emulsifying and antibacterial activities, glycolipids have great potential as food additives and food preservatives. Furthermore, the valorization of food byproducts via the production of glycolipid biosurfactant has received much attention because it permits the bioconversion of byproducts on valuable compounds and decreases the cost of production. Generally, the use of glycolipids in many fields requires their retention from fermentation media. Accordingly, different strategies have been developed to extract and purify glycolipids. © 2016 Society of Chemical Industry., (© 2016 Society of Chemical Industry.)

Unlabelled: The effect of calcinated calcium spray on Escherichia coli O157:H7 87-23 population reduction during radish sprout production was studied. Artificially inoculated radish seeds were soaked in sodium hypochlorite (NaOCl) solutions (200 and 20000 ppm), rinsed in distilled water, and sprayed with water or a calcinated calcium solution during sprouting. Microbial plate count was obtained at each step of the process and germination rate was determined after 72 h of sprouting. Scanning electron microscopy (SEM) was done on treated seeds and sprouts to locate which parts were populated by the E. coli cells. The results showed that the active compound in the calcinated calcium was calcium oxide. The treatment of 200 ppm NaOCl soaking followed by 0.04% calcinated calcium spray resulted in no microbial growth after a 72-h sprouting, while maintaining a high germination rate. The 0.4% calcinated calcium spray significantly reduced the germination rate and is therefore not recommended. Soaking the seeds in a 20000 ppm chlorine solution achieved the highest E. coli count reduction (1.65 log CFU/g). However, the E. coli cells that survived the 20000 ppm chlorine soak grew to 6 log CFU/g sprouts after a 72-h sprouting, significantly higher than the initial count on the seeds. The SEM microimages showed that the bacteria were mostly located in the roots of the radish sprouts and all across the seed surface. The E. coli O157:H7 87-23 cells appeared to be located in biofilms or embedded into the radish sprout tissues during sprouting., Practical Application: The seed sanitation treatment with 20000 ppm chlorine solution that is currently used by the sprout industry was once again found to be ineffective in eliminating inoculated pathogenic cells. More importantly, the remaining cells that have survived the chlorine wash would grow during sprouting to reach an alarmingly high cell concentration. The new observation of E. coli cells and sprout tissue interaction manifested as embedding of the cells in sprout tissues, if confirmed, will have a significant impact on the microbial safety intervention strategies used in the sprout industry. This research demonstrated the importance of eliminating all pathogens on the seeds before germination and sprouting., (© 2011 Institute of Food Technologists®)

Despite extensive literature both supporting and critiquing the Green Revolution, surprisingly little attention has been paid to synthetic fertilizers' health and environmental effects or indigenous farmers' perspectives. The introduction of agrochemicals in the mid-twentieth century was a watershed event for many Mayan farmers in Guatemala. While some Maya hailed synthetic fertilizers' immediate effectiveness as a relief from famines and migrant labor, other lamented the long-term deterioration of their public health, soil quality, and economic autonomy. Since the rising cost of agrochemicals compelled Maya to return to plantation labor in the 1970s, synthetic fertilizers simply shifted, rather than alleviated, Mayan dependency on the cash economy. By highlighting Mayan farmers' historical narratives and delineating the relationship between agricultural science and postwar geopolitics, the constraints on agriculturists' agency become clear. In the end, politics, more than technology or agricultural performance, influenced guatemala's shift toward the Green Revolution.