Agricultural Biodiversity Weblog

September 25, 2026September 25, 2026

Joining the dots on food plant diversity

We have access to more kinds of food plants, yet the world’s diets and production systems have never been more alike. That is the paradox at the heart of Food plant diversity in a rapidly changing world, an unusually broad review by Colin Khoury (very much friend of the blog) and colleagues. It has all the latest data, but it also does several other things that make it more than a conventional state-of-the-art paper.

For one, it brings together diversity at several levels that are too often discussed separately: species, varieties and genes, of course, but also the diversity of diets, farming systems, foodways and the knowledge associated with them. It traces the extraordinary expansion and movement of food plants over the past 12,000 years alongside the much more recent trend towards homogenisation. The result is the weird world we have today: more kinds of crops available globally, but less difference between what people in different places eat.

Colin and friends also take a hard look at what we don’t know. We have surprisingly little systematic evidence for how much food-plant diversity has actually been lost, how vulnerable today’s production systems are because of increasing uniformity, or what is happening to less visible forms of diversity, such as nutritional and chemical variation. There’s a call for better monitoring, including an early-warning system for crop vulnerability. Now where have I heard that before?

And the paper connects the dots between conservation approaches that have tended to live in separate boxes: genebanks, botanic gardens, community seed banks, on-farm initiatives, protected areas, breeding programmes and markets. Genebanks are all well and good, but diversity also needs to keep going in fields, landscapes, cuisines and communities. Again, not particularly new, but it’s good to have it repeated, brought up to date, and placed in the broadest possible context.

A couple of those dots are discussed in more detail in a companion opinion paper, Enhance food plant diversity conservation and use through greater coordination between genebanks and botanic gardens, which asks what might become possible if two of the world’s major plant conservation communities worked a bit more closely together. Which must be possible because they are nicely complementary, so neither should fear the other as a competitor.

The review paper maps the problem. The opinion piece explores a possible route towards a more joined-up conservation system. Which leaves us with its own small paradox: conserving food plant diversity requires flattening some of the differences within a remarkably diverse conservation community. Happy Crop Diversity Day 2026.

September 24, 2026September 24, 2026

Mind the seed

Seeing the new Tree Seed and Seedling Field Guide Series from the Landscape Alliance reminded me that I’d also meant to write about the International Principles and Standards for Native Seeds in Ecological Restoration. That’s been sitting on my to-do list for a while now. It is not one of those standards documents that tells you what everyone ought to do and leaves the messy details to somebody else. It really gets into the…well, I was going to say weeds but that would be all wrong. Let’s just say it’s pretty comprehensive: where the seeds should come from, how much to collect, how to maintain genetic diversity, how to process and store them, how to test viability and germination, and what information should accompany the seed lot to the person who eventually plants it. There is even a pro-forma label. In other words, lots of advice about how not to screw up the supply chain for seeds of native plants to be used in habitat restoration and the like.

The new field guides sit very nicely alongside that. They take the same concern with quality and turn it into practical guidance for people producing and using tree seeds and seedlings in Kenya and Rwanda. The scales and specifics are different, but the underlying problem is much the same: restoration depends on getting seeds from a wild population to a restoration site without losing the information, quality or diversity on which success depend. The standards provide a framework for doing that; the field guides help people put it into practice specifically for trees in East Africa.

It’s all a welcome corrective to the tendency to think that restoration begins when you put a seed or seedling in the ground. Quite a lot has to go right before you get to that bit. One question, though. Are all these various principles, standards, guides and recommendations integrated into the digital workflow for forest restoration that I blogged about a couple of weeks back?

September 22, 2026September 21, 2026

Where have all the nutrients gone?

The “nutrient collapse” story has been doing the rounds for years, and we’ve been picking at it on the blog for almost as long.

Back in 2009, Jeremy looked at evidence that older crop varieties could contain more minerals, protein and other nutrients than newer ones, and discussed various possible reasons, including the intriguing possibility of a “genetic dilution” effect as breeders selected for yield.

By 2012, we were stressing that the evidence was more complicated than the headlines suggested, and in 2019 we linked to the latest critical review of the evidence by Robin Marles of the Bureau of Nutritional Sciences in Canada.

Now the latest episode of the BBC’s indispensable More or Less podcast asks again whether carrots are becoming less nutritious, prompted by a listener who clearly hasn’t been following our blog, and turns to Dr Marles, now retired, for the answer. Which hasn’t really changed much.

The bottom line is that breeding for yield and other commercially important traits can change the balance of what ends up in the harvest, and that we have historically been much better at measuring tonnes per hectare than what is actually in those tonnes.

September 22, 2026September 22, 2026

Organic roundup

I could have sworn I had at least Nibbled Our World in Data’s Is organic farming better for the environment than conventional farming? But it doesn’t look like it. Fortunately, Jeremy gets to grips with it in his latest newsletter. Along with that autumnal favourite, the apple, and lots of other interesting stuff.

September 21, 2026September 20, 2026

Brainfood: From data to action

A three-decade-long analysis shows rising threatened species and responsibility gaps in global supply chains. Data says that we must make responsibility for biodiversity traceable from production to final demand.
Development of an evidence-based integrated germplasm prioritization framework for conservation and breeding. Data says: here’s how to extract some defensible conservation and breeding priorities from this large collection.
A methodological framework for the standardised evaluation of olive genetic resources: GEN4OLIVE harmonized protocols. Data says that we should standardise phenotyping across countries to make olive germplasm more useful in breeding.
High-throughput phenotyping of Bambara groundnut [Vigna subterranea (L.) Verdc.] seed morphometrics using videometer. Data says that we should use multispectral imaging to really speed up seed characterization and breeding in Bambara groundnut.
Predicting the cross-continental spread of the cassava brown streak disease epidemic in sub-Saharan Africa. Data says that we must strengthen surveillance and delivery systems for clean planting material before cassava brown streak disease reaches Nigeria.
The Sustainability of Robusta Coffee Under Global Change—A Review. Data says that we must match robusta production to genuinely suitable environments, plus invest in lower-input cultivation and alternative coffee species.
Borassus Akeassii Facing Societal and Environmental Challenges: Case Study of the Gouin Society of Southwestern Burkina Faso. Data says that we need to conserve this multipurpose palm once central to Gouin livelihoods together with the local knowledge and practices that make it useful.