Inequality of nitrogen use and loss in global croplands caused by climate change

Maintaining food production while reducing agricultural pollution is a grand challenge under the threats of global climate change, which has exerted negative impacts on agricultural sustainability. How agricultural nitrogen use and loss respond to climate change is rarely understood. Here we show that climate change leads to inequality of cropland nitrogen use and loss across global regions based on historical data for the period 1961-2018 from 143 countries. Increases of yield, nitrogen surplus and nitrogen use efficiency (NUE) are identified in 30% of countries, while reductions are observed for the remaining 70% of countries, as a result of climate change. Farm size changes further intensify the inequality of nitrogen use and pollution in global croplands. Yet, enlarging farm size can facilitate climate change adaptation, by which global cropland NUE could be increased by one-third in 2100 compared to 2018 under future shared socioeconomic pathways. Our results would be of great significance to sustain global agriculture as well as eliminate national inequalities on food production and agricultural pollution control.

Recombination of standing variation in a multi-hybrid swarm drove adaptive radiation in a fungal pathogen and gave rise to two pandemic plant diseases

Adaptive radiations fuel speciation and are characterized by rapid genetic diversification and expansion into new ecological niches. Historically, these processes were believed to be driven by selection on novel mutations but genomic analyses now indicate that standing variation and gene flow often have prominent roles. How "old" variation is combined, however, and its resulting genetic architecture within newly adapted populations is not well understood. We reconstructed a recent radiation in the fungus, Pyricularia oryzae, that spawned a population pathogenic to eleven grass genera, and caused two new plant diseases: wheat blast - already a serious threat to global agriculture - and gray leaf spot of ryegrasses. We show that the new population evolved in a multi-hybrid swarm using only the standing variation that was present in seven individuals from five distinct, host-specialized lineages. Sexual and parasexual recombination within the swarm reassorted key host-specificity factors and generated more diversity in possibly just a few weeks than existing lineages had accumulated over hundreds to thousands of years. We suggest that the process was initiated by sexual opportunity arising when a fertile fungal strain was imported into Brazil on Urochloa introduced as forage for beef production; and we further contend that the host range expansion was largely fortuitous, with host selection playing little, if any, role in driving the process. Finally, we believe that our findings point to an overlooked role for happenstance in creating situations that allow organisms to skirt rules that would normally hold evolution in check.

The Applications of Nanotechnology in Crop Production

With the frequent occurrence of extreme climate, global agriculture is confronted with unprecedented challenges, including increased food demand and a decline in crop production. Nanotechnology is a promising way to boost crop production, enhance crop tolerance and decrease the environmental pollution. In this review, we summarize the recent findings regarding innovative nanotechnology in crop production, which could help us respond to agricultural challenges. Nanotechnology, which involves the use of nanomaterials as carriers, has a number of diverse applications in plant growth and crop production, including in nanofertilizers, nanopesticides, nanosensors and nanobiotechnology. The unique structures of nanomaterials such as high specific surface area, centralized distribution size and excellent biocompatibility facilitate the efficacy and stability of agro-chemicals. Besides, using appropriate nanomaterials in plant growth stages or stress conditions effectively promote plant growth and increase tolerance to stresses. Moreover, emerging nanotools and nanobiotechnology provide a new platform to monitor and modify crops at the molecular level.

Contract Farming towards Social Business: A New Paradigm

The current paper conceptualises an innovative, sustainable social business contract farming model by blending three essential business aspects, namely, relational norms, social capital, and social business dimensions. In the case of contract farming, evidence shows that the social aspect and social business-based contract farming model are over-sighted. This study offers an efficient social business contract farming model by, first, reviewing the conventional contract farming model and, secondly, by developing and proposing a robust, multidimensional model for contract farming. This proposed framework may have profound implications for the agriculture sector and may provide a strong sustainable contract farming management guideline for the global agriculture industry.

Climate Change Concerns of Saudi Arabian Farmers: The Drivers and Their Role in Perceived Capacity Building Needs for Adaptation

Climate change is a serious threat to the sustainability of global agriculture and food supply that necessitates taking appropriate action for building resilient food production systems and preserving rural economies. In this regard, farmers’ beliefs and concerns about the effects of climate change on agriculture may influence their adoption of adaptation and mitigation practices to address this emerging issue. This work was undertaken to evaluate farmers’ level of concern about climate change in the Jazan province of Saudi Arabia. The study also explored the role of various socioeconomic indicators in shaping farmers’ concerns and highlights various capacity-building initiatives that can be applied at the community level for effective adaptation. Ordered logistic regression was used to study the relationship between farmers’ level of concern and their need for capacity-building initiatives to tackle climate change. Results indicated that insect infestation is the farmers’ top concern, followed by higher crop-diseases incidence and drought. Regression analysis revealed that farmers’ income is a major factor that reduces their concern for insect infestation and crop disease while increases concern for drought. Credit access and information availability have a mixed impact on the farmers’ concern level. Capacity-building initiatives deemed necessary included establishing frequent contacts with extension personnel, timely warnings on droughts and other natural hazards, the training of farmers and extension workers, easy credit facilities, improvement in rural infrastructure and creation of awareness to address specific concern stimulus.

Changing Global Governance Context for Food Security and Nutrition

Through collective action, global governance helps identify, understand, and address problems that spill over national boundaries. Those problems include maintaining peace and security; developing and implementing rules with regard to trade in commodities and services, capital flows, and migration; containing transboundary pests and diseases; slowing global warming; and providing aid for needy countries and peoples. Specific international organizations (five discussed in Chapter 6) address these issues). The difference between global and national governance is that there is no global government. Global governance, through various international bodies and institutions, complements regional, national, and local governance in an important way and is the sum total of the informal and formal ideas, values, rules, norms, procedures, practices, policies, and institutions that govern all actors—states, intergovernmental organizations, civil society, nongovernmental organizations, transnational corporations, and the general public. The number of actors on the global governance scene has proliferated, as has the sheer number of international initiatives that have been started to mobilize incremental international funding in support of food security and nutrition since the 2007 food crisis. Many of the initiatives are reviewed in this chapter, showing that the amount of incremental funding in support of food security and nutrition, beyond traditional sources raised, was insignificant compared to the number of international consultations held. The Global Agriculture and Food Security Program was a notable exception, as well as the Agricultural Market Information System. This situation appears to have changed for the better since the COVID-19 pandemic. The chapter examines the relationship between global, regional, national, and local governance.

Towards CRISPR/Cas9-based gene drive in the diamondback moth Plutella xylostella

Promising to provide powerful genetic control tools, gene drives have been constructed in multiple dipterans, yeast and mice, for the purposes of population elimination or modification. However, it remains unclear whether these techniques can be applied to lepidopterans. Here, we used endogenous regulatory elements to drive Cas9 and sgRNA expression in the diamondback moth, (Plutella xylostella), and test the first split-drive system in a lepidopteran. The diamondback moth is an economically important global agriculture pest of cruciferous crops and has developed severe resistance to various insecticides, making it a prime candidate for such novel control strategy development. A very high level of somatic editing was observed in Cas9/sgRNA transheterozygotes, although no significant homing was revealed in the subsequent generation. Although heritable, Cas9-medated germline cleavage, as well as maternal and paternal Cas9 deposition was observed, rates were far lower than for somatic cleavage events, indicating robust somatic but limited germline activity of Cas9/sgRNA under the control of selected regulatory elements. Our results provide valuable experience, paving the way for future construction of gene drive-based genetic control strategies in DBM or other lepidopterans.