CROP ADAPTATION TO CLIMATE CHANGE-High-Temperature Stress in Drought Prone Areas: ALL ARTICLES

FAO/IAEA Co-ordinated Research Project on Climate Proofing Crops: Genetic Improvement for Adaptation to High Temperature in Drought-Prone Areas and Beyond

Maladaptation of U.S. corn and soybeans to a changing climate

We quantify long-run adaptation of U.S. corn and soybean yields to changes in temperature and precipitation over 1951–2017. Results show that although the two crops became more heat- and drought-tolerant, their productivity under normal temperature and precipitation conditions decreased. Over 1951–2017, heat- and drought-tolerance increased corn and soybean yields by 33% and 20%, whereas maladaptation to normal conditions reduced yields by 41% and 87%, respectively, with large spatial variations in effects. Changes in climate are projected to reduce average corn and soybean yields by 39–68% and 86–92%, respectively, by 2050 relative to 2013–2017 depending on the warming scenario. After incorporating estimated effects of climate-neutral technological advances, the net change in yield ranges from (−)13 to 62% for corn and (−)57 to (−)26% for soybeans in 2050 relative to 2013–2017. Our analysis uncovers the inherent trade-offs and limitations of existing approaches to crop adaptation.

Root Response to Soil Water Status via Interaction of Crop Genotype and Environment

Flooding and drought are major causes of reductions in crop productivity. Root distribution indicates crop adaptation to water stress. Therefore, we aimed to identify crop roots response based on root distribution under various soil conditions. The root distribution of four crops—maize, millet, sorghum, and rice—was evaluated under continuous soil waterlogging (CSW), moderate soil moisture (MSM), and gradual soil drying (GSD) conditions. Roots extended largely to the shallow soil layer in CSW and grew longer to the deeper soil layer in GSD in maize and sorghum. GSD tended to promote the root and shoot biomass across soil moisture status regardless of the crop species. The change of specific root density in rice and millet was small compared with maize and sorghum between different soil moisture statuses. Crop response in shoot and root biomass to various soil moisture status was highest in maize and lowest in rice among the tested crops as per the regression coefficient. Thus, we describe different root distributions associated with crop plasticity, which signify root spread changes, depending on soil water conditions in different crop genotypes as well as root distributions that vary depending on crop adaptation from anaerobic to aerobic conditions.

Mutation breeding, genetic diversity and crop adaptation to climate change

This book presents reviews on the application of the technology for crop improvement towards food and nutrition security, and research status on mutation breeding and associated biotechnologies in both seed crops and vegetatively propagated crops. It also presents perspectives on the significance of next-generation sequencing and bioinformatics in determining the molecular variants underlying mutations and on emerging biotechnologies such as gene editing. Reviews and articles are organized into five sections in the publication: (1) Contribution of Crop Mutant Varieties to Food Security; (2) Mutation Breeding in Crop Improvement and Climate-Change Adaptation; (3) Mutation Induction Techniques for Enhanced Genetic Variation; (4) Mutation Breeding in Vegetatively Propagated and Ornamental Crops; and (5) Induced Genetic Variation for Crop Improvement in the Genomic Era. The contents of this volume present excellent reference material for researchers, students and policy makers involved in the application of induced genetic variation in plants for the maintenance of biodiversity and the acceleration of crop adaptation to climate change to feed a growing global population in the coming years and decades.

Improving Crop Adaptation through Improved Phenology Prediction: A Case Study with Chickpea

Flowering time is a key phenological stage which in chickpea has been considered to be mainly driven by photoperiod and temperature. [...]

Uncertainty Propagation in Crop Adaptation Responses to Climate Change: A Modelling Perspective

The human population is exponentially increasing and is projected to reach or exceed 9 billion by 2050 [...]

Humic substances: a valuable agronomic tool for improving crop adaptation to saline water irrigation

Availability of fresh water for crop irrigation is becoming scarce and rather expensive. In this context, the research about the potential reutilization of non-conventional water sources becomes highly relevant, principally in arid and semi-arid areas. On many occasions, these new water resources involve water with a moderate concentration of salt, making it necessary to improve plant growth under moderate saline conditions. Besides plant breeding techniques, the use of molecules able to improve plant adaptation to saline conditions has great interest. Between these molecules, humic substances (HS) have proven to be efficient as stress-protectors under specific conditions of stress intensity and moment of application. The HS are main components of the soil organic matter and dissolved organic matter resulting from the biotic and abiotic transformation of fresh organic matter in natural ecosystems. Although knowledge about their structure is still under open debate, HS contain aromatic and aliphatic domains presenting O-, N- and S- containing functional groups with high biological and chemical activities. The aim of this presentation is to summarize the main effects of humic acids (HA) applied either on the root or on the shoot, on the metabolism and hormonal balance of plants cultivated under normal and stressing conditions, from studies carried out for our group and collaborations during the last years. Summarizing, all these results show HA as a promising tool for improving crop adaptation to irrigation using moderate saline water sources.