The plot thickens

I’m slowly making my way through the open access book “Sustainable Agroecology: Actors, Practices, Experiences and Perceptions,” edited by Javier Becerril García, Paulina Martínez Isidro, Praveen Jha, Elisabeth Tuider, and Andreas Thiel. It’s like 300 pages, so I may be some time.

The book brings together 15 case studies from different authors around the world exploring how agroecological approaches can support rural livelihoods and nutrition, while sustaining agricultural diversity, local knowledge and cultures. Several chapters highlight the role of farmers, particularly women, in maintaining traditional varieties through seed selection, saving and exchange.

One describes the Maya milpa system in Yucatán, where the Three Sisters — maize, beans and squash — are grown alongside other crops and managed as part of a wider landscape of home gardens, fallows and forests. Another examines the remarkable diversity of Mexican home gardens, which can contain more than a hundred plant species and serve as reservoirs of useful plants, many of them threatened.

A particularly interesting example comes from Chiapas, where a group of Indigenous women, the “Guardians of the Seeds”, established a community seed store and organised the conservation and exchange of native crops, combining traditional knowledge with technical support. The book also looks at the revival of underutilised crops in Europe, including bere barley in Orkney and local bean and wheat varieties in Italy and Greece, showing how new markets can help bring neglected diversity back into cultivation.

The authors have relatively little to say about formal genebanks — but that’s ok. The contribution of the book is to underline what genebanks cannot do alone: maintain the knowledge, seed systems, markets and farming practices that keep crop diversity in use and allow it to continue evolving.

Brainfood: Gender edition

  • Informality in food environments: a systematic review of nutrition, livelihood, and sociopolitical outcomes and implications for food policy. A review of 327 studies across 64 countries shows women make up the majority of informal vendors, and their businesses are shaped by gendered constraints: eg access to public space, regulation, childcare and personal safety. Food policy needs to recognise informal food environments and address their social and political dimensions, not treat them as peripheral to the formal food system.
  • Role of urban and peri-urban agriculture in nutritional diversity, cultural resilience and community-based food security in an Eastern Himalayan city. A study of 150 households in Imphal, Northeast India, finds that almost all urban households engage in some form of food production, with women managing most of it. Container, rooftop and terrace cultivation help maintain access to a diversity of fresh vegetables and herbs as traditional homestead gardens disappear under urbanisation, contributing significantly to nutritional security, cultural continuity and community resilience.
  • Land tenure as a catalyst: Synergizing gender equality and agrobiodiversity conservation for sustainable development in Asian vulnerable areas. An analysis of 1,089 households across 12 sites in five Asian countries finds that women with secure land tenure manage greater crop species and variety diversity, because they can make independent decisions. The relationship varies considerably among countries and agroecologies, but it seems that strengthening women’s land rights can deliver benefits for both gender equality and agrobiodiversity conservation.
  • The gender dynamics of crop varietal choices in rural Kenya: navigating risk, diversification, and decision-making. Drawing on interviews and focus groups across five Kenyan counties, this study examines how women and men negotiate crop varietal choices in the context of unequal access to resources and climate uncertainty. Both value production characteristics, but women place greater emphasis on processing and consumption qualities, while men tend to prioritise marketability and yield potential. Land ownership, household authority and cultural norms influence whose preferences prevail, with implications for conservation, breeding priorities and seed systems.
  • Gender matters in seed system assessments: evidence from smallholder farms in Morocco, Senegal, and Madagascar. Surveys of 1,054 smallholder farms reveal substantial differences between women’s and men’s accounts of seed management and sourcing practices. Women are systematically underrepresented, partly because researchers commonly interview male household heads and overlook the constraints imposed by women’s care responsibilities. Gender-disaggregated data collection is thus essential for understanding how seed systems actually work, and seed assessments can reproduce the very inequalities they are supposed to measure.
  • Sons or seeds: gender, care work, and agrobiodiversity in translocal households of rural China. Fieldwork in two mountainous Chinese villages explores the dilemma facing rural women who balance caring for family members with maintaining local seeds and agroecological practices. As men migrate for work, women take on more agricultural responsibilities, but are also expected to provide childcare and look after older relatives. Women’s knowledge and labour sustain agrobiodiversity while remaining undervalued and frequently uncompensated. Don’t romanticise women as natural guardians of seeds while overlooking the economic and personal sacrifices involved.
  • Feminist Agroecology and Criollo Hens: Women’s Everyday Resistance in Colombia. The expansion of industrial poultry production in Colombia threatens traditional backyard hen keeping, undermining women’s autonomy and increasing dependence on commercial inputs. However, everyday practices of care, intergenerational knowledge sharing and community cooperation help sustain alternative poultry systems, a form of resistance to industrialisation and an important source of women’s socioeconomic autonomy and community resilience.
  • Preserving Indigenous Peoples’ values and rights in food composition programmes: A call for agreed international guidelines. Food composition research can help broaden understanding of the nutritional value of Indigenous foods, but it also raises questions about who controls the knowledge and how it is used. Drawing on examples from First Nations in Canada, Māori in Aotearoa New Zealand, Sámi in Sápmi and Indigenous Peoples in Northeast India, the authors call for participatory approaches grounded in free, prior and informed consent, data sovereignty and access and benefit-sharing. The idea is to ensure that Indigenous Peoples, especially women, are recognised as rights-holders and active knowledge holders, rather than simply sources of information for scientific research.
  • To round things off, here’s a policy brief on Gender and Social Inclusion in Agrobiodiversity Conservation from the CBD Women’s Caucus and the Alliance of Bioversity International and CIAT, aimed at the just-concluded COP17 of the CBD.

Nibbles: Standing variation, Indigenous dogs, Austrian apples, Jordanian olive oil, Island foods

  1. Ancient farmers didn’t have to wait for the genetic diversity that made domestication possible. They selected from variation already present in wild plants, including the ancestors of rice and maize. Domestication was as much about spotting (or happening upon) useful differences as creating new ones.
  2. English colonists in America called Indigenous dogs “wolves,” revealing as much about colonial perceptions as about the animals themselves. This history of Indigenous dogs shows how unfamiliar animals were classified through peculiarly European ideas about wildness.
  3. Austria is bringing forgotten apple varieties back to life. Saving old varieties in genebanks is one thing: getting people to grow, sell and eat them is another, but it can be done. Or at least tried.
  4. Jordan’s olive-oil heritage centres on traditional varieties such as Nabali and ancient Rumi trees, but most production is consumed locally, leaving exports limited and making provenance, cultivar and harvest date important indicators for buyers. Compare and contrast with Austrian apples.
  5. Small island developing states have distinctive food cultures and ingredients, but face particular challenges in building sustainable and resilient food systems. FAO’s A Taste of SIDS explores the connections between island food, biodiversity and culinary heritage. Nice to see diversity within crops considered, though a few local variety names would have been nice.

The apples of our eye

Apples have been another recurring obsession on the blog, maybe because they make the conservation problem unusually tangible, and immediate. Pretty much everyone thinks they know what an apple is, but the diversity hidden behind that word is enormous, and not much visible in supermarkets. A lot of it may have disappeared, but you can pretty much guarantee a slew of heritage apple stories in the press come autumn (and so it begins), so I guess people care. Here’s a selection of posts about apples spanning 15 years. There’s a lot more out there in the archive for you to explore.

Let’s start at the beginning, or as close to it as the genetics can get us. In 2016’s The Adam and Eve of apples?, I discussed the wild apple forests of southeastern Kazakhstan, where all of the world’s apple varieties can be traced back to an ancestral population of Malus sieversii — spread, if you believe the more colourful tellings, by bears eating the sweetest fruit and pooping the seeds around the forest. As usual, though, the genetics turned out to be more interesting than the headline. The cultivated apple isn’t a simple straight line from one mother tree; it’s the product of a long history of movement, hybridization and exchange between wild and domesticated populations all along the old trade routes out of Central Asia.

But those forests are in danger. Back in 2009, in Wild fruit relatives threatened in Central Asia, I looked at how the wild relatives of apples and other crops were vanishing along with their habitat. Among them was Malus niedzwetzkyana, the remarkable red-fleshed apple of Kyrgyzstan. These aren’t just obscure wild trees: they represented genetic diversity that has already made its way into cultivated apples, and might still have something to offer breeders. That red-fleshed apple came back a year later in Not the world’s first red apple. A new red-fleshed variety was being breathlessly presented in the press as a novelty — not GM, just 15 years of patient crossing and 20,000 rejected seedlings — but nature had got there first. M. niedzwetzkyana has been doing red flesh for millennia.

The cultivated stock has its own story of loss. In 2009’s Saving an apple a day, I looked at the loss of American apple varieties, and at the people trying to rescue what remained. Thousands of named varieties had once been grown in the United States; only a fraction survived in orchards, collections and the memories of the people who knew what they tasted like. It was a nice illustration of a familiar conservation paradox: you can lose a lot of diversity without even noticing, because the supermarket keeps selling you apples.

However, that same year, a study added a wrinkle to the “thousands lost” narrative. In Lost apples found, Jeremy pushed back a little on the standard version of the story — the one where 6,800 of 7,100 named 19th-century American apple varieties are simply gone. A team from the University of Arizona and USDA had gone looking for ghosts among old apple trees on historic farmsteads in Arizona, Utah and New Mexico. Only 34 of the resulting genotypes matched a known variety. The other 110, spread across 160 trees, matched nothing on record. Some of those are probably unnamed seedlings that never had a name to lose in the first place. But some, surely, are the supposedly lost varieties everyone had given up on. Not extinct, just lurking.

Seven years on, the USDA apple folks came back with another version of the answer. In As American as apples, Gayle Volk summarized her and Adam Henk’s trawl through historic nursery catalogues, which turned up 891 named apple cultivars grown in the US before 1908. They went looking for the 150 that seemed to matter most. The payoff: 90% are still findable today, safely tucked away in genebanks, private collections or specialist nurseries. Only 51 high-priority cultivars remained unaccounted for in any collection. For now.

The lesson isn’t that genetic erosion doesn’t happen. It plainly does, and 30 fruit nurseries vanishing a year is not nothing. No, the lesson is that “extinct” is much harder to prove than “endangered,” and pomologists with their equivalent of a swab kit keep turning out to be more patient, and luckier, than we have any right to hope.

Conserving what’s left, of course, depends on people as much as on collections and gene sequencers. In 2014, I offered up Irish eyes smiling about apple conservation. The post was prompted by Michael Hennerty’s beautiful book on the Irish apple, but the real story was the people who had nurtured the 68 varieties documented in the book over the years. Conservation often depends on a motley collection of people keeping things alive long enough for some fancy institution to discover that they matter. A few years later, Jeremy went into much more detail on Irish apples on his podcast.

Institutions, though, can be just as precarious as the work of any orchard-keeper or amateur gardener. Across the Irish Sea, the story of the UK’s apple collection showed just how fragile even a major national genebank can be. The National Fruit Collection at Brogdale in Kent, with its hundreds of apple varieties, came under threat when its funding was thrown into doubt, prompting a succession of stories about sales, new management and relocations. Oh, and royalty. Anyway, the collection is fine, but the saga was a reminder that conservation is not just about keeping things alive. You have to keep them alive with enough institutional resilience that they can survive the next crisis.

Taken together, these posts highlight a sometimes overlooked aspect of safeguarding agrobiodiversity. Conservation is not just putting varieties safely into collections, nor, on the other hand, is it just protecting wild populations from destruction. Apples show that the two are connected — or should be. These are, in the jargon, complementary conservation strategies. The diversity in a genebank has a history outside it, and the diversity out in the wild and in farms may only have a future in a genebank. We really do need both, it’s not just mom and apple pie rhetoric.

Cassava, revisited, and revisited again

Cassava has been a persistent thread through this blog since the beginning. It first appears as a staple with a dark side: capable of keeping people fed, but also of causing a nasty disease under some conditions. Over time, it resurfaced repeatedly, showing how one crop can illuminate many of the key issues in agrobiodiversity conservation and use. As part of our anniversary celebrations, let’s pull some posts out and see how that might work…

An early post we called Detoxifying cassava looked at the complex ways konzo epidemics in Africa are linked to the consumption of bitter cassava. A later Nibble pointed to a very digestible (sic) introduction to cassava and cyanide. And Manihot esculenta, I presume? widened the lens historically, drawing on Dr Livingstone’s Zambesi Expedition papers to show how he understood cassava’s diversity, its promise and its danger back in the day.

Several posts over the years have looked at how well we now know and conserve the diversity of the crop. Gaps in cassava collection in Africa highlighted sounded an alarm: eastern and southern Africa seemed to be under‑represented in international genebanks. Later, More on cassava germplasm from Brazil and an earlier post compared the geographic distribution of CIAT’s genebank holdings with the that of both accessions and cultivation in Brazil, illustrating how national and international collections overlap — and where they don’t.

A post on safety duplicating germplasm collections explained the mechanics of backing up diversity, using Embrapa’s genebank as a concrete example. It also included a reference to the global cassava conservation strategy, during the development of which I got schooled on the diversity of the crop. And a paper on sources of pest resistance in cassava we included in a Brainfood showed the value of genebank holdings, identifying landraces in CIAT’s global collection with resistance to thrips, mites, and whiteflies.

This particular arc culminates in a summary of two papers on 50 years of cassava conservation at CIAT, which looks at that genebank from both ends: what went in over five decades, and what actually came out in breeding. A recent Nibble notes that cassava’s diversity is spread across multiple genebanks, and why that’s a good thing, up to a point.

Then came the TME 419 saga: Is there more than one TME 419 cassava? unpacked confusion around an IITA genebank accession number; I say TME 419, you say TMe‑419 revisited the same named clone in Nigerian fields years later. Another intricate tale centred around how some modern varieties got their resistance to post-harvest rotting. Spoiler alert: a wild relative was involved.

Genebanks, however, are not the full story. Cassava’s diversity also has to survive in farmers’ fields, where diseases constantly test its resilience. An early post, Ho hum … another deadly disease, placed cassava brown streak virus (CBSV) alongside then emerging threats like Ug99 wheat rust. CBSV was duly much in the news a few years later in 2011, and we were of course all over it, though not always one hundred percent correct in our judgements. That’s what the comments are for.

A Nibble on cassava pests questioned the crop’s “indestructible,” Rambo-like image as new problems appeared in Southeast Asia and elsewhere. An experiment on cassava degeneration, Twitter‑style focused on what to do about the widespread viral infection of cassava planting material across Africa, which badly affects performance. And a Nibbles roundup on cassava bad and good news captured an apparent mismatch between FAO worry and CGIAR optimism back in 2011. Maybe we should do an update on that, now I think about it.

Another theme has been how the crop is promoted, produced, and woven into everyday food systems today. In Cassava on a roll? I traced production ups and downs in Kenya, intrigued by seeing new products in supermarkets on my return to the country. I followed that up with The flour of Kenyan agrobiodiversity marketing, which shows cassava (with finger millet) being used to diversify staple flour, connecting conservation to real products and diets. And a Nibble on Ugandan cassava from a couple of years back highlights local innovation in value chains, if you interpret it charitably. No doubt all part of the African cassava revolution touted by Forbes in a 2023 Nibble.

I hope this roundup of our past encounters with cassava, incomplete as it inevitably is, has given you a little taste of what twenty years of this blog have been about: following stories as they unfold, picking up old threads, occasionally digging really deep, other times not deep enough. Do search for your favourite crop in the archive, and tell us what you come up with.