In situ conservation—harnessing natural and human‐derived evolutionary forces to ensure future crop adaptation

Abstract

Ensuring the availability of the broadest possible germplasm base for agriculture in the face of increasingly uncertain and variable patterns of biotic and abiotic change is fundamental for the world's future food supply. While ex situ conservation plays a major role in the conservation and availability of crop germplasm, it may be insufficient to ensure this. In situ conservation aims to maintain target species and the collective genotypes they represent under evolution. A major rationale for this view is based on the likelihood that continued exposure to changing selective forces will generate and favor new genetic variation and an increased likelihood that rare alleles that may be of value to future agriculture are maintained. However, the evidence that underpins this key rationale remains fragmented and has not been examined systematically, thereby decreasing the perceived value and support for in situ conservation for agriculture and food systems and limiting the conservation options available. This study reviews evidence regarding the likelihood and rate of evolutionary change in both biotic and abiotic traits for crops and their wild relatives, placing these processes in a realistic context in which smallholder farming operates and crop wild relatives continue to exist. It identifies areas of research that would contribute to a deeper understanding of these processes as the basis for making them more useful for future crop adaptation.

Consumers’ Valuation of Farmers’ Varieties for Food System Diversity

“…Starting at the very root, these schemes empower farmers to make use of the large genetic diversity in crops neglected over the years. Moreover, they again breed and multiply their own seeds, leading to locally adapted crops, more diverse agricultural landscapes and a more diverse offer of food [13,14,22].…”

Evolutionary and food supply implications of ongoing maize domestication by Mexicancampesinos

“…This is important because we cannot predict the future, and the presence of genetic diversity is fundamental for adaptive evolution in response to changing environmental conditions [68,69]. Therefore, the larger the scale and the more diverse the scope of this process, the more genetic diversity available; and thus, the higher the probability that some alleles, although currently rare or unknown, will become widely adaptive under new, and in many cases unpredictable, conditions [19] (that is, the higher the option value of genetic diversity under evolution). This constitutes not only an evosystem service, but also a positive externality-an uncompensated positive impact of one agent's actions (i.e.…”

Bioprospecting Wild Biodiversity in Romania: Case Study - Gentiana lutea

“…Such a protocol will protect the over-collecting from the wild, will ground financial revenues for the country of origin and at the same time will catalyze the optimization ratio between in situ and ex situ conservation strategies for ensuring the preservation of all genetic resources (M.R. BELLON & al., [65]).…”