Growing and Eating Lettuce in Space

Journeying outside of low-earth orbit and setting up long-term or permanent colonies on other planets or moons is fraught with challenges. One obvious challenge is food production. Regular deliveries from Earth are costly and risky, and freshness isn’t always an option. So, perhaps food can be grown on site? NASA is currently exploring this question by carrying out a series of experiments using an aptly named piece of hardware called Veggie, which was delivered and installed on the International Space Station in the spring of 2014. Experiments began shortly thereafter, and last month NASA astronauts finally got to taste the leaves of their labor for the first time.

Veggie is a plant growth chamber that was developed by Orbital Technologies Corporation. It provides environmental conditions – such as light, temperature, and airflow – that are suitable for plant growth. Accompanying the delivery of Veggie were three sets of planting pillows – specially designed pouches that contain growing media, fertilizer, and seeds. The pillows are placed on rooting mats inside Veggie and watered using a wicking system . Light is delivered by red, blue, and green LEDs. The red and blue wavelengths are necessary for plant growth, and the green wavelength helps the plants look more appealing to the astronauts.

Veggie: an expandable plant growth facility designed for the International Space Station - photo credit: NASA/Bryan Onate

Veggie: an expandable plant growth facility designed for growing plants on the International Space Station – photo credit: NASA/Bryan Onate

Two sets of pillows were seeded with a variety of red romaine lettuce called ‘Outredgeous.’ This particular plant was chosen because it is easy to grow, tastes good, and has high nutritional value. The first lettuce harvest was sent back to earth last October for a food safety analysis. Once it was deemed free of harmful bacteria and safe to eat, the astronauts were cleared to start the second round of red romaine, which they did in early July 2015. The third set of planting pillows contain zinnia seeds, and according to statements made by astronaut Scott Kelly on Twitter, it doesn’t sound like those have been grown yet.

After caring for the second round of lettuce plants for 33 days, it was finally time to taste them. The astronauts first cleaned each leaf with citric acid based sanitizing wipes and then sampled the leaves plain. Next they tried them with a little olive oil and balsamic vinegar. They shared their experience in real time via Twitter, which is documented in this New York Times article. They saved a few leaves for their Russian friends who were out on a spacewalk, and then packaged the rest up to be frozen and sent back to Earth for analysis.

Outredgeous Territorial Seed Company

Lactuca sativa ‘Outredgeous’ – the variety of red romaine lettuce grown and eaten by NASA astronauts on the International Space Station (photo credit: Territorial Seed Company)

This isn’t the first time plants have been grown and eaten in space. Russian cosmonauts grew and consumed mizuna (Japanese mustard) back in 2002 using a plant growth chamber developed in collaboration with a lab at Utah State University. They have also used the growth chamber to grow peas, radishes, and other plants. Read more about these experiments here.

Growing plants in space, apart from providing fresh food, offers psychological benefits. In an otherwise sterile and metallic environment, having something green (or red, in the case of the lettuce) to look at and care for has the potential to lift the moods of crew members aboard the space station. NASA scientist, Dr. Gioia Massa, who is overseeing the project sums it up nicely, “The farther and longer humans go away from Earth, the greater the need to grow plants for food, atmosphere recycling, and psychological benefits. I think that plant systems will become important components of any long-duration exploration scenario.”

Want to learn more? Read about the project here, here, and here. Also watch this video about growing plants in space.

 

Just for fun, there is a great children’s fiction book involving plants in space called June 29, 1999 by David Wiesner which is definitely worth a look.

More “Plants in Space” Posts on Awkward Botany:

Growing Plants on the Moon

Growing Plants in Outer Space

Botany and Everyday Chemistry

What’s not to love about plants? They provide us with oxygen, food, medicine, fuel, fibers, and countless other things. They help filter groundwater and sequester carbon. They beautify our landscapes and communities. They provide habitat for wildlife and help reduce soil erosion. And the list goes on.

But there is more to plants than meets the eye. There is something deeper within – at their cellular and molecular levels – that is just as worthy of our fascination and appreciation as the blooms that beautify our yards and the fruits that fill our tables, and that is the abundant and diverse world of chemical compounds present in the botanical kingdom.

But how does one gain an understanding and appreciation for such a subject. Luckily, there is a blog for that. It’s called Compound Interest. Authored by UK chemistry teacher, Andy Brunning, Compound Interest explores the “chemistry and chemical reactions we come across on a day-to-day basis.” Much of what Andy writes about doesn’t have anything to do with plants – fireworks, bacon, gunpowder, snowflakes, etc. – but a sizeable portion of his posts do (evidenced particularly by the Food Chemistry category). For example: Did you know nutmeg is hallucinogenic? Have you ever wondered why avocados turn brown so quickly? Why is it that some people have such a strong aversion to cilantro (aka coriander)? What makes coffee bitter, chili peppers spicy, and catnip so attractive to cats?

These and so many other questions are answered by Andy in a fun and approachable way. One thing that makes Compound Interest so approachable is the use of infographics to tell the stories and explain the science. Each post is accompanied by an infographic featuring photos of the subject, structural formulas of the chemicals, and short descriptions.  For example, this infographic explains why beets are red and why our urine turns red after eating them:

Chemistry-of-Beetroot

The infographics can also be downloaded as pdf files, like this one that explains the chemistry behind the smell of fresh-cut grass.

In this manner, the images and files can be easily shared with others. In fact, Andy encourages this practice, provided that the originals are not altered and that Compound Interest is given proper credit. He is particularly interested in seeing his infographics used in a classroom setting. Read more about the content usage guidelines here. Produced by someone who is obviously passionate about chemistry, these posts and graphics are meant to educate and excite people about everyday chemistry both in the botanical world and beyond.

Podcast Review: Gastropod

I am a voracious consumer of podcasts and have a long list that I regularly listen to. Despite being unable to get through all of them in a reasonable amount of time, I am still continually on the lookout for more. I am particularly interested in science or educational podcasts – something that I can listen to for an hour or so and learn new things about the world, whether it be breaking news or historical facts.

This year a new podcast was born – a podcast exploring the science and history of food.  It is called Gastropod, and it has quickly found its way into my regular rotation of podcast consumption. It wasn’t a difficult climb either, as the general theme of the podcast is something that fascinates me and the hosts do a top-notch job presenting the information and telling the stories.

gastropod

Gastropod is hosted by Cynthia Graber and Nicola Twilley, each of whom have impressive backgrounds in researching and reporting on science, technology, food, and other topics for a variety of outlets both large and small. Among numerous other projects, Nicola has a blog called Edible Geography and Cynthia contributes regularly to Scientific American’s 60 Second Science podcast. Gastropod just happens to be their latest endeavor, and it is a welcome one.

Full length episodes of Gastropod are released once a month, with “snack-sized interludes” called Bites released in between to tide listeners over until the next helping. Since Gastropod is in its infancy (the first episode was released in September 2014), catching up on past episodes is simple. An afternoon of binge listening will do it.

Topics covered so far in full length episodes include the history and evolution of cutlery (which involves a taste test using spoons made of various metals), a discussion with Dan Barber about his book The Third Plate, an exploration of the emerging “microbe revolution” in agriculture (which piggybacks on an article that Cynthia wrote for NOVANext and which I reviewed back in July), and the rising popularity of kelp (“the new kale”) and the growth of seaweed farms. Bite-sized episodes have discussed things like modern day domestication of wild plants, underused American seafood resources, a meal replacement drink called Soylent, the expansive yet underappreciated (and disappearing) diversity of apples, and subnatural foods (smoked pigeon, anyone?).

So far every episode has been great, but if I had to pick a favorite, the interview with Dan Barber really stands out. His discussion of “ecosystem cuisines” – which moves beyond the farm-to-table movement – was new to me but seems like an important idea and one that I would like to see play a pivotal role in the development of science-based sustainable agriculture.

Gastropod is a young but promising podcast, and I look forward to many more captivating episodes in 2015 and beyond. Learn more about Gastropod and its hosts here.

Do you have a favorite podcast, science-themed or otherwise? Share it in the comments section below.

Using Wild Relatives to Improve Crop Plants

This is the thirteenth in a series of posts reviewing the 17 articles found in the October 2014 Special Issue of American Journal of Botany, Speaking of Food: Connecting Basic and Applied Science.

Back to the Wilds: Tapping Evolutionary Adaptations for Resilient Crops through Systematic Hybridization with Crop Wild Relatives by Emily Warschefsky, Varma Penmetsa, Douglas R. Cook, and Eric J. B. von Wettberg

The nature of domestication involves the narrowing of genetic diversity through a series of crosses and selections that results in organisms well suited for particular environments and/or purposes. In the short term, this arrangement seems to suit our needs, that is until the climate shifts, novel pests and diseases invade, agricultural soils become degraded, or some other calamity ensues. Then we must select a new form to take the place of the old one that is no longer suitable. Additionally, the varieties currently in use may be doing well within their current parameters, but their performance may be found lacking if placed in different environments or grown in alternate systems, such as one that relies on fewer petrochemical inputs.

The wild relatives of crop plants have a long history of being used in breeding programs to provide specific traits for improving domesticated varieties. Interest in this has increased thanks to technological advancements (such as marker-assisted selection and genomic selection) and the greater availability of germplasm. Introgression (the transfer of genes from one species to another through hybridization and repeated backcrossing) using crop wild relatives has mainly been aimed at introducing traits like resistance to specific pests and diseases, tolerance of certain abiotic stresses, and greater yields. In other words, crop wild relatives are typically screened for a few main traits that might be useful in breeding programs, neglecting the possibility that the introgression of a larger suite of traits may be beneficial long-term.

This article discusses the possibility of using “crop wild relative collections that [have been] systematically built to represent the range of adaptations found in natural populations” to improve crop plants. By using these “purpose-built populations that are hybrids between crops and their wild relatives,” crop plants introgressed with “full sets of wild diversity” will be better adapted to a wide variety of environments, soils, climates, and agricultural systems. In order to “illustrate the gains that are possible,” the authors review published studies of hybridization (both naturally occurring and human mediated). They then “propose a multi-step framework for utilizing naturally occurring variation in wild relatives of crops.”

Grapefruit (Citrus x paradisi) - A hybrid between sweet orange (Citrus sinensis) and shaddock (Citrus maxima) that "occurred far beyond the region of domestication and rather recently [the 18th centruy]." (photo credit: wikimedia commons)

Grapefruit (Citrus x paradisi) – A hybrid between sweet orange (C. sinensis) and shaddock (C. maxima) that “occurred far beyond the region of domestication and rather recently [the 18th century].” (photo credit: wikimedia commons)

Hybridization can occur between two individuals of different cultivars, varieties, subspecies, species, genera, etc. The genetics of the resulting offspring is a combination of the two parents, and depending on the circumstances, a hybridization event “can have drastically different consequences.” For this reason, “hybridization is thought of as both a creative and a restrictive force in evolution.” It is, however, “the potential for the production of novelty that makes hybridization such an intriguing – and potentially useful – phenomenon.”

In their discussion of hybridization between crops and their wild relatives, the authors reveal some “obstacles that limit the use of wild relatives in breeding programs.”

  • Poor Agronomic Performance – “Crop wild relatives often lack important domestication traits.” They may have shattering pods, irregular germination timing, or phenologies that inhibit their use in certain regions.
  • Poor Representation in Germplasm Collections – “Only 2-6% of international germplasm collections are of crop wild relatives.” There are some crop wild relatives that are well-represented, but others have been “poorly collected” or “almost ignored,” and some crops still “lack well-identified wild relatives.” One reason for this disparity is that a large number of these plants “occur in geopolitically unstable areas where collection has long been complicated.”
  • Unpredictability of Phenotypes – “Phenotypes of wild individuals are often assessed in agricultural settings, a largely uninformative practice when the overall wild phenotype is specifically adapted for fitness in the wild but not cultivated settings.” This makes for an inaccurate comparison with domesticated varieties, so when “crop-wild hybrids” are formed, phenotypes are hard to predict. Backcrossing is necessary in order to recover the “essential crop phenotype” while capturing the desired traits of the wild relative.

The authors also highlight the need for conservation of crop wild relatives, as “these species are nearly universally threatened.” The catalog of threats to their survival is similar to so many other threatened species: the loss, fragmentation, and degradation of habitats, climate change, invasive species, and over-harvesting (“in the case of medicinally and pharmaceutically useful species”). One threat, perhaps ironically, is agricultural crops crossing with nearby wild relatives, especially where transgenic genes in crops are being transferred to wild populations. In order to better realize the potential that crop wild relatives have in improving domesticated varieties, they must first be protected in their natural habitats.

Desert sunflower (Helianthus deserticola) - One of three hybrid species born of H. annuus and H. petiolaris, "highlighting the expanded potential of hybrid species...through colonization of extreme habitats where neither parental species can survive." (photo credit: www.eol.org)

Desert sunflower (Helianthus deserticola) – One of three hybrid species born of H. annuus and H. petiolaris, “highlighting the expanded potential of hybrid species…through colonization of extreme habitats where neither parental species can survive.” (photo credit: www.eol.org)

The authors propose a 5 step plan for systematic utilization of crop wild relatives in agricultural breeding programs. The steps include building a comprehensive collection of crop wild relatives, sequencing their genomes, creating purpose-driven hybrid populations between wild relatives and crop plants, developing a predictive network of genotype-phenotype associations, and deploying identified phenotypes into crop breeding efforts. This article is one of the open access articles in this issue. If you are interested in this topic, including this 5 step plan, I encourage you to read the article to learn more. 

Cultivated Sunflowers and Their Wild Relatives

This is the ninth in a series of posts reviewing the 17 articles found in the October 2014 Special Issue of American Journal of Botany, Speaking of Food: Connecting Basic and Applied Science.

Transistions in Photoperiodic Flowering Are Common And Involve Few Loci in Wild Sunflowers (Helianthus; Asteraceae) by Lucas P. Henry, Ray H. B. Watson, and Benjamin K. Blackman

The seasonal timing of flowering is an important trait to consider in crop plants, because it dictates where geographically a particular crop can be grown and also plays a role in fitness and yield. Flowering time is determined by a combination of genetics and environmental factors. One of the major environmental factors is day length, a phenomenon known as photoperiod response (or photoperiodism).  There are three main types of photoperiod response: short-day (plants flower when “grown in day lengths below a critical maximum threshold”), long-day (plants flower when “grown in day lengths above a critical minimum threshold”) and day-neutral (“plants flower at the same time under all day length conditions”). A plant’s response to day length can be obligate – restricted to a particular response – or facultative – capable but not restricted. Understanding the genetics of photoperiod response is important for breeding efforts, and can help in the development of crop varieties that have improved yields and that can be either grown in broader geographic areas or that are specifically selected for local regions.

Agricultural breeding programs often investigate wild relatives of crop plants for potential traits that could lead to improvements. There is “renewed interest” in these investigations “because genome-enabled methods [of identifying desirable genes] and international investment in germplasm resources have dramatically reduced the associated labor, time, and risk.” The authors of this study, recognizing extensive variation in flowering time in both common sunflower (Helianthus annuus) and its wild relatives, examined the genetic basis for this variation in an effort to support sunflower breeding programs.

Common Sunflower, Helianthus annuus (photo credit: Wikimedia commons)

Common Sunflower, Helianthus annuus (photo credit: wikimedia commons)

Helianthus is a genus consisting of around 70 species, most of which are native to North America (a few occur in South America). Several species in this genus are cultivated as food crops and/or as ornamental plants. H. annuus is the most commonly cultivated species, valued for its edible seeds and the oil they produce as well as for various other things. Wild relatives of H. annuus have “been a frequent source of genetic raw material for agricultural innovation,” aided by the fact that “barriers to interspecies crosses are incomplete or can be overcome through embryo culture or chromosomal doubling.” Helianthus is a diverse genus, including generalist species occurring in “diverse environments over broad geographic regions” and specialist species occurring in “habitats characterized by high temperature, water, or salt stress.” For this reason, “wild sunflowers are prime sources to mine for alleles that confer higher yield in new or marginal” agricultural settings.

A relatively small subset of Helianthus species were involved in this study; however, the subset represented a “phylogenetically dispersed sample.” One interesting finding was that the evolution of an obligate short-day requirement for flowering has occurred in several species, “particularly those with ranges restricted to the southern United States.” The authors suggest that a reason for this finding could be that “long, hot, and humid summers” in this region “may be unfavorable for growth or reproduction.” Thus, while populations of H. annuus “likely escape these conditions by flowering in the long days of late spring,” other Helianthus species put off “flowering until the arrival of cooler, less humid falls.” Flowering during cooler times is beneficial because pollen fertility decreases and seed maturation slows at high temperatures. The risk of fungal pathogens attacking flowers and dispersed seeds is also reduced during periods of lower humidity.

Another important finding was that the diversity in photoperiod response in Helianthus appears to have a “relatively simple genetic architecture.” If this is the case, it could “greatly facilitate rapid crop improvement by marker-assisted selection.” Further studies are necessary, specifically those involving “intra- and interspecific crosses segregating for variation in photoperiod response,” in order to confirm the authors’ findings and justify “broader investment of resources into these applied efforts.”

Nuttall's Sunflower (Helianthus nuttallii), one of Common Sunflower's wild relatives (photo credit: www.eol.org)

Nuttall’s Sunflower (Helianthus nuttallii), one of Common Sunflower’s wild relatives (photo credit: www.eol.org)

While much was learned from this study, the authors acknowledge the need for “future investigations with greater taxonomic and environmental sampling.” Researchers recently produced a “draft genome” for sunflower. This additional resource will greatly aid breeding programs and further inform studies, like this one, that are interested in the “mechanistic factors and ecological agents that have promoted the emergence of the great diversity and lability in photoperiod response observed in wild sunflowers.”

An Underutilized Crop and the Cousins of a Popular One

This is the fourth in a series of posts reviewing the 17 articles found in the October 2014 Special Issue of American Journal of Botany, Speaking of Food: Connecting Basic and Applied Science.

Genetic Diversity in Carthamus tinctorius (Asteraceae; Safflower), An Underutilized Oilseed Crop by Stephanie A. Pearl and John M. Burke

Safflower (Carthamus tinctorius) was first domesticated in the Fertile Crescent about 4,500 years ago. It was originally desired for its flowers which were used in dye making. Commercial production of safflower began in North America in the 1950’s, where it is now mainly grown for its seeds which are used to produce oil for human consumption and are a main ingredient in bird seed mixes. Despite this, it is categorized as an “underutilized crop,” one “whose genetic potential has not been fully realized.” With increased interest in food security and feeding a growing population, researchers are turning to new and underutilized crops in order to increase the “availability of a diverse assemblage of crop species.”

A major step in improving a crop plant is understanding the genetic diversity that is available within its gene pool. With this aim in mind, researchers observed a “broad cross section of the safflower gene pool” by examining the DNA of a “worldwide sampling of diversity from the USDA germplasm collection [134 accessions consisting of 96 from the Old World and 38 from the New World]”, 48 lines from two major commercial safflower breeding programs in North America, and 8 wild collected safflower individuals.

Safflower, Carthamus tinctorius (photo credit: www.eol.org)

Safflower, Carthamus tinctorius (photo credit: www.eol.org)

Researchers found that the cultivated safflower varieties had a significant reduction in genetic diversity compared to the wild safflower plants. They also noted that the 96 Old World accessions could be grouped into “four clusters that corresponded to four different geographic regions that presumably represent somewhat distinct breeding pools.” They found that the wild safflowers “shared the greatest similarity with the Iran-Afghanistan-Turkey cluster” from the Old World group of accessions, a finding that “is consistent with safflower’s presumed Near Eastern center of origin.”

The researchers determined that there may be “agronomically favorable alleles present in wild safflowers,” and that “expanded efforts to access wild genetic diversity would facilitate the continued improvement of safflower.” Safflower is an important but underused oilseed crop that is adapted to dry climates; studies like this one that can lead to further crop improvements may help bring it out of niche production and into more widespread use.

The Wild Side of a Major Crop: Soybean’s Perennial Cousins from Down Under by Sue Sherman-Broyles, Aureliano Bombarely, Adrian F. Powell, Jane L. Doyle, Ashley N. Egan, Jeremy E. Coate, and Jeff J. Doyle

Soybean production is a major money maker in the United States ($43 billion total revenue in 2012); corn is the only crop that tops it. Soybean oil has myriad uses from food to feedstock and from pharmaceuticals to biofuel. As much as 57% of the world’s seed oil comes from soybeans produced in the United States. Hence, soybean (Glycine max and its wild progenitor, G. soja) is a well researched crop. Most research has been focused on the two annual species in the subgenus Soja; “less well known are the perennial wild relatives of soybean native to Australia, a diverse and interesting group that has been the focus of research in several laboratories.”

Given the agricultural importance of soybean and the increasing demands that will be placed on this crop as population rises, it is imperative that improvements continue to be made. Exploring soybean’s “extended gene pool,” including both its annual “brother” and its perennial “cousins,” will aid in making these improvements.

Soybean's wild annual relative, Glycine soja (photo credit: www.eol.org)

Soybean’s wild annual relative, Glycine soja (photo credit: www.eol.org)

Perennial soybeans in the subgenus Glycine include around 30 species. They are adapted to a wide variety of habitats “including desert, sandy beaches, rocky outcrops, and monsoonal, temperate, and subtropical forests.” They are of particular interest to researchers because several of them are allopolyploids, meaning that they have more than the usual two sets of chromosomes and that the additional sets of chromosomes were derived from different species. The authors state that “the distributional differences between diploids and independently formed polyploids [in the subgenus Glycine] suggests underlying ecological, physiological, and molecular differences related to genome doubling and has led to the development of the group as a model for studying allopolyploidy.” The group is also worth studying because they demonstrate resistance to various soybean pathogens and are adapted to a variety of environmental conditions.

By continuing to work with soybean’s perennial cousins to gain a better understanding of “polyploidy and legume evolution,” the authors hope to apply their research to achieve increases in soybean yields. Past research suggests that the study of polyploidy in the perennial soybeans could lead to crop improvements in areas such as photosynthesis, nitrogen fixation, flowering time, and disease resistance.

Glycine tomentella - one of soybean's perennial cousins (photo credit: www.eol.org)

Glycine tomentella – one of soybean’s perennial cousins (photo credit: www.eol.org)

 

On the Origins of Agriculture

This is the first in a series of posts reviewing the 17 articles found in the October 2014 Special Issue of American Journal of Botany, Speaking of Food: Connecting Basic and Applied Science.

Agricultural Origins from the Ground Up: Archaeological Approaches to Plant Domestication by BrieAnna S. Langlie, Natalie G. Mueller, Robert N. Spengler, and Gayle J. Fritz

Concern about food and the environment has been on the rise for a while now. Interest in healthy food grown and produced in a responsible manner has prompted people to investigate where their food is coming from. Archaeologists studying plant domestication and the rise of agriculture are also concerned with where our food came from; however, their research efforts are more focused on prehistoric events rather than on what is being stocked on today’s grocery store shelves.

The authors of this paper, all archaeologists specializing in paleoethnobotany or archaeobotany, offer a broad overview of the study of plant domestication and the emergence of agricultural economies. In their studies the authors “treat domestication as a process that originally preceded the formation of agricultural economies” and they define domestication as “genetic and morphological changes [in] a plant population in response to selective pressures imposed by cultivation.”

The first section of the paper explains why certain theoretical approaches to thinking about early plant domestication should be revised. These approaches include a centric view of plant domestication, single domestication trajectories, rapid pace plant domestication, and domestication being coupled with the development of agricultural economies.

The concept of centers of origin refers to specific regions in the world where the majority of crop domestication is thought to have occurred. Often these are regions where a high number of wild relatives of crops are found and where large civilizations emerged. But research has revealed numerous locations in various parts of the world where crop domestication occurred independently from traditional centers of origin leading archaeologists to further explore a noncentric view of domestication.

Related to the centers of origin debate is the single vs. multiple domestications debate. Single site domestication refers to a plant being domesticated in one location and then spread to other locations. Multiple site domestication refers to the same plant being domesticated in multiple sites independently. With the aid of genetic research, crops that were once thought to have been domesticated in a single region and then disseminated to other regions are now being shown to have multiple domestication sites. For example, it has been suggested that barley was domesticated independently in various locations, including the western Mediterranean region, Ethiopia, Morocco, and Tibet, as well as various parts of Southwest Asia.

Barley - Hordeum vulgare (photo credit: Wikimedia commons)

Barley – Hordeum vulgare (photo credit: wikimedia commons)

Concerning the pace of crop domestication, “many scholars have presented evidence that domestication was slower and more gradual than previously envisioned” probably because the first domesticated crop plants were not “developed by plant breeders with clear end products in mind.” On this point, the authors conclude that debates over timelines are “likely to continue for some time,” and that “close communication between geneticists and archaeologists, including those with archaeobotanical expertise” will be necessary to tell the full story.

Domestication is typically viewed as a precursor to agriculture. But the authors point out that domestication occurred first and that agriculture did not immediately follow. To illustrate this point, they tell the story of the bottle gourd (Lagenaria siceraria), possibly the oldest domesticated plant. Native to Africa, the gourds likely floated across the Atlantic Ocean to the Americas (they also made their way to East Asia and other places) where they were domesticated multiple times by various groups of people at least 10,000 years ago. The gourds had numerous potential uses including containers, rattles, net floats, and even food (the young, immature fruits are edible). Large gourds with thick rinds were preferred by early humans, and the seeds of these were planted. The plants needed little attention, so caring for them did not mean having to adopt a sedentary lifestyle. The authors conclude that “although this example might seem peripheral to the development of serious food-producing economies or social complexity, it highlights early, intimate plant-people relationships and the abilities of people to modify their environments to enhance availability of desirable resources.”

Bottle gourds (Lagenaria sicericia) were possibly the earliest domesticated plant species (photo credit: eol.org)

Bottle gourds (Lagenaria siceraria) were possibly the earliest domesticated plant species (photo credit: www.eol.org)

In the next section of the paper, the authors discuss new and improved methods being used today to “address questions about the timing, scale, and causes of domestication.” Narrowing down the dates that plants were first domesticated is a major interest of archaeologists, and advances in radiocarbon dating have assisted in this quest. When DNA is being extracted, it is important to know the age of the material being analyzed in order to better reveal its history. Combining several methods for analyzing the data – especially as these methods are improved and new methods are developed – is  crucial.

Advances in microscopy have helped to better analyze morphological changes in plants over time as well as to examine microfossils, like starch granules, pollen, and phytoliths (silica particles left behind after a plant decays). Observing phenotypic changes in fruits, seeds, and other plant parts and determining the presence of things like starch granules and pollen helps us to understand the pace and scope of domestication as well as to determine when certain domesticated plants were introduced to areas outside of their perceived center of origin. Advances in the science of taphonomy – “the study of decay processes following the death of an organism until it is fossilized or exhumed” – also aid researchers in better understanding the stories behind plant domestication.

Scanning electron microscope (SEM) image of pollen grains from common sunflower - Helianthus annuus (photo credit: Wikimedia commons)

Scanning electron microscope (SEM) image of pollen grains from common sunflower – Helianthus annuus (photo credit: wikimedia commons)

Working with experts in other areas of archaeology will also lead to greater understanding of plant domestication and the emergence of agricultural economies. The authors give examples of how studying human and animal bones can provide information about plant domestication and state that “other classes of archaeological data, such as household structure and storage features, agricultural and culinary tools, and soil morphology” will aid in better understanding “how and why domestication occurred as an historical and evolutionary process.”

Next the authors discuss anthropological views on the causes of plant domestication. One of the main debates among anthropologists when discussing agriculture is whether or not early humans were “pushed” or “pulled” into agricultural economies. Did increasing populations and/or decreasing availability of resources compel people to produce more of their own food or did human populations cultivate and domesticate plants in areas where resources were readily available, allowing them to live sedentary and stable existences? The authors conclude that “it is not necessary for one of these scenarios to explain all transitions to agriculture” as agriculture emerged independently in multiple locations around the globe, each time under its own specific set of circumstances.

The final section of the paper is a short discussion on the relatively under-researched topic of the diet and cuisine of ancient humans. Surely, a desire for particular foods and beverages lead to cultivation and domestication. The authors assert that “cuisines provide people with social identities, nationalism, spirituality, and a package of cognitive tools for coping with their environment. Without a doubt, culturally constructed food preferences played a role in the origins and spread of agriculture.”

This is a brief summary of a well-researched and detailed article concerning the fascinating topic of early plant domestication. Honestly, my synopsis hardly does it justice, so I urge you to read it for yourself if this topic interests you. I particularly appreciated the emphasis that the authors placed on using multiple methods and tools to collect and interpret data and how our perspectives should be revised as new and updated data emerge. The call for multiple disciplines to come together in collaboration to better understand the history of domestication and agriculture is also encouraging. In summation the authors state that “archaeological evidence indicates that every case of transition form hunter-gatherers to agricultural economies was unique … Identifying the specific nature of when, where, and how domestication occurred will undoubtedly elucidate how agriculture transformed the trajectory of human societies.”

Speaking of Food: A Special Issue of American Journal of Botany

“At the center of discussions about agriculture and the future of food in a changing climate are the plants that we grow for food, fiber, and fuels and the science that is required to understand, improve, and conserve them.”

That is a line from the opening paragraph of the introduction to the October 2014 issue of American Journal of Botany, Speaking of Food: Connecting Basic and Applied Plant Science. In this Special Issue, the American Journal of Botany – inspired by Elizabeth Kellogg’s 2012 presidential address to the Botanical Society of America – endeavors to demonstrate ways in which basic plant biology research can benefit the applied science of agriculture, and how this “use-inspired” research can help address the challenges of feeding a growing population in a changing climate.

speaking of food_ajb

In its 100 year history, the American Journal of Botany, has published hundreds of papers that serve to advance agricultural and horticultural sciences. However, this connection has not always been made explicit. With this special issue, they are hoping to change that by “illustrat[ing] that ‘basic’ and ‘applied’ are not two discrete categories, nor are they even extremes of a linear continuum.” “Basic” research can be used to answer questions and solve “human-centered problems,” and “applied” research can “illuminate general biological principles.” When both approaches to scientific inquiry come together, everyone benefits.

I originally chose to study horticulture because I was interested in growing food in a sustainable and responsible manner. During my studies, I gained a greater interest in the broader field of horticulture as well as an interest in botany. After receiving a degree in horticultural and crop sciences, I decided to pursue a Master’s Degree. I wanted to study green roof technology, an applied science that incorporated my interests in both horticulture and sustainability. The school that I ended up going to did not have a horticulture program, so I enrolled in a biological sciences program. It was there, while doing applied science research on green roofs and taking mostly botany related science courses, that I deepened my love for science and began to see how basic science had applications, not just in horticulture and agriculture, but in all aspects of life.

That explains my great interest in this recent issue of American Journal of Botany, and why I was so excited when I heard about it. Using science to understand and address the challenges that we face today (challenges that, many of which, are a result of human activity) is intriguing to me. Based on my interest in horticulture, food production, and sustainability, establishing and advancing science-based sustainable agriculture is incredibly important to me. And so I have decided that, over the next several posts, I will provide reviews of each of the 17 articles in AJB’s Special Issue. Each post will offer a brief overview of one or more articles, outlining the basic premises and findings of each study. If your interest is peaked, and I hope it will be, you can go on to read more about each of the studies. The Introduction to this issue gives an excellent overview of the articles, so I won’t include that here. I’ll just dive right in. If you feel inclined, read ahead, otherwise stay tuned and I will preview you it all for you over the next several weeks.

Our Backyard Farm and Garden Show: Fall 2014

I had every intention of documenting this year’s garden more thoroughly, but as things tend to go, the days got busy and the year got away from me. Now here we are in mid-October, still waiting for the first frost but accepting its imminence, watching reluctantly as another growing season comes to a close. We took several pictures but few notes, so what follows is a series of photos and a few reflections on what transpired this past year in, what Flora likes to call, Our Backyard Farm and Garden Show.

Abundance

Abundance

I guess I should start at the beginning. Last year I was living in an apartment. I was growing things in two small flower beds and a few containers on my patio. That had been my story for about a decade – growing what I could on porches and patios and in flower beds of various apartments in a few different parts of the country. At one point I was living in an apartment with no space at all to grow anything, and so I attempted to start a garden in the backyard of an abandoned, neighboring house – geurilla gardening style – but that didn’t go so well. At another location I had a plot at a community garden. The three years I spent there were fun, but definitely not as nice as stepping outside my door and into my garden.

Earlier this year, I moved in with Flora. She was renting a house with a yard, so when I joined her, I also joined her yard. Flora is a gardener, too; she had spent her first year here growing things in the existing garden spaces but wanted to expand. So we did. We enlarged three beds considerably and built four raised beds and two compost bins. We also got permission to grow things in the neighbor’s raised beds. And that’s how our growing season started – coalescence and expansion.

Then summer happened. It came and went, actually. Most days were spent just trying to keep everything alive – moving sprinklers around, warding off slugs and other bugs, and staking things up. Abundance was apparent pretty much immediately. We started harvesting greens (lettuce, kale, collards, mustards) en masse. Shortly after that, cucumbers appeared in concert with beets, turnips, basil, ground cherries, eggplants, tomatoes, carrots, peppers, etc. Even now – anticipating that first frost – the harvest continues. We are uncertain whether or not we will remain here for another growing season; regardless, we are considering the ways in which we might expand in case we do. Despite the amount of work that has gone into our garden so far, we still want to do more. Apparently, our love of gardening knows no bounds.

A view of our side yard. It is pretty shady in this section of the yard but we were still able to grow kale and collards along with several different flowers and herbs.

A view of our side yard. It is pretty shady in this bed but we were still able to grow kale and collards along with several different flowers and herbs.

 

We grew several varieties of lettuce. This is one that I was most excited about. It's called 'Tennis Ball.' It is a miniature butterhead type that Thomas Jefferson loved and used to grow in his garden at Monticello.

We grew many varieties of lettuce. This is one that I was most excited about. It’s called ‘Tennis Ball.’ It is a miniature butterhead type that Thomas Jefferson loved and grew in his garden at Monticello.

 

'Shanghai Green' Pak Choy

‘Shanghai Green’ Pak Choy

 

'Purple Top White Globe' Turnips

‘Purple Top White Globe’ Turnips

 

A miniature purple carrot with legs.

A miniature purple carrot with legs.

 

Two cucumbers hanging on a makeshift  trellis. I can't remember what variety they are. This why I need to remember to take better notes.

Two cucumbers hanging on a makeshift trellis. I can’t remember what variety they are. This why I need to remember to take better notes.

 

'San Marzano' Roma Tomato. We grew three other varieties of tomatoes along with this one.

‘San Marzano’ Roma Tomatoes. We grew three other varieties of tomatoes along with this one.

 

The flower of a 'Hong Hong' sweet potato. We haven't harvested these yet, so we're not sure what we're going to get. Sweet potatoes are not commonly grown in southern Idaho, so we're anxious to see how they do.

The flower of a ‘Hong Hong’ sweet potato. We have not harvested these yet, so we are not sure what we are going to get. Sweet potatoes are not commonly grown in southern Idaho, so we are anxious to see how they do.

 

We grew lots of flowers, too. 'Black Knight' scabiosa (aka pincushion flower)was one of our favorites.

We grew lots of flowers, too. ‘Black Knight’ scabiosa (aka pincushion flower) was one of our favorites.

 

Some flower's we grew specifically for the bees, like this bee's friend (Phacelia hastate).

We grew some flowers specifically for the bees, like this bee’s friend (Phacelia tanacetifolia).

 

We grew other flowers for eating, like this nasturtium.

We grew other flowers for eating, like this nasturtium.

 

Even the cat loves being in the garden...

Even the cat loves being in the garden…

It has been an incredible year. “Abundant” is the best word that I can think of to describe it. We have learned a lot through successes and failures alike, and we are anxious to do it all again (and more) next year. Until then we are getting ready to settle in for the winter – to give ourselves and our garden a much needed rest. For more pictures and semi-regular updates on how our garden is growing, follow Awkward Botany on tumblr and twitter, and feel free to share your gardening adventures in the comments section below.

Feeding the World with Microbes

Back in the mid 1900’s, after the tragic days of the Dust Bowl in North America, new agricultural techniques and technologies were developed and distributed in the name of food security. These developments included higher yielding plant varieties, synthetic fertilizers and pesticides, and advancements in irrigation and other management practices. This period in time was termed the Green Revolution, and it truly was a remarkable time. Agricultural advancements that came out of this period have helped us feed the world and stave of starvation for millions of people. Today, issues of hunger and starvation are political problems, not necessarily agricultural ones. However, the human population continues to grow, and today’s 7 billion people is projected to reach up to 10 billion (or more) in the coming decades. The world’s best farmland is either already in use, degraded, or being used for other things. This means that we must find a way to feed a growing population with the diminishing farmland that is available. We may be producing enough food now (despite the distribution problem), but will we be able to produce enough in the future? The hunt for the Green Revolution 2.0 is on.

“According to the [UN’s Food and Agriculture Organization], most of the growth in production…has to come from increasing yields from crops. Selective breeding doesn’t seem to be offering the types of dramatic yield increases seen in the past. Meanwhile, genetic engineering has yet to lead to any significant increase in yields. Now, many scientists are saying that we’ve been looking at the wrong set of genes.”

These are the words of Cynthia Graber, author of an article that appeared last month on PBS Online’s NOVANext entitled, “The Next Green Revolution May Rely on Microbes.” In it she explores the argument that increasing future yields will depend on better understanding the soil’s microbial community and its complex interaction with the plant community. The big question: if microbes can be artificially bred – the same way virtually all agricultural plants have been – might they help us increase food production?

Microbial life in the soil is incredibly diverse. In one teaspoon of soil, there can be millions of individual microbes including bacteria, fungi, protozoa, algae, and nematodes. Our current understanding of soil life is extremely limited, akin to our understanding of outer space and the depths of the oceans. That is because, as stated in Graber’s article, “perhaps 1% of all soil microbes can be grown in a petri dish, the conventional model for such research.” This limits our ability to study soil microbes and their interactions with other living things. We do, however, acknowledge that the interactions between the roots of plants and soil microbes is incredibly important.

Fruiting Body of an Ectomycorrhizal Fungus (photo credit: eol.org)

Fruiting Body of an Ectomycorrhizal Fungus (photo credit: eol.org)

One major player in these interactions is a group of fungi called mycorrhizae. “Mycorrhizal fungi cannot survive without plants, and most plants cannot thrive without mycorrhizal fungi.” It is a symbiotic relationship, in which the fungi offer plants greater access to water and nutrients, and plants feed sugars derived from photosynthesis to fungi. Recent advancements in genetics have allowed researchers to better analyze the genes in microbes like mychorrizal fungi and determine the functions of them. Through selective breeding, microbes can be produced that will offer even greater benefits to plants, thereby increasing yields. For example, some microbes help plants tolerate heat and drought. Isolating the genes that give microbes these abilities, and then breeding these genes into other microbes might allow for a wider palette of plants to receive this kind of assistance.

In researching this article, Graber followed a Swiss researcher to Colombia where he was testing lines of mychorrhizal fungi on cassava. The fungi were specifically selected to increase a plant’s access to phosphorous. This is one of many experiments that are now under way or in the works looking at specially bred microbes in agricultural production. It’s an exciting new movement, and rather than spoil too much more of Graber’s article, I implore you to read it for yourself. Share any comments you may have in the comment section below, and expect more posts about plant and microbe interactions in the future.

Cynthia Graber appeared at the beginning of a recent episode of Inquiring Minds podcast to talk about her article. I recommend listening to that as well.