16 Sep 2016

Biodiversity Month: Edible Plants - About the Caimito

Photo: Forest and Kim Starr / CC BY 2.0

By: Jorge Ventocilla

This world is a paradox: in the name of liberty, it makes you choose between the same things, and the same things both on the table or on TV

Eduardo Galeano


Undoubtedly, diversity is a distinctive characteristic of life. It not only serves as an ornament, it makes life possible. For our species, in particular, both biological and cultural diversity are essential. They give us options for thriving in this tiny piece of universe we call home.
The topic for this full moon is biological diversity, and I would like to focus on diversity that serves as food. Particularly, I would like to comment on the caimito, as an example of our local diversity.
I must confess, now that we are talking about food, that I am not a big fan of junk food. Many of you may not be either. To me, it usually means an upset stomach, that is why I have my apprehensions. It has an aftertaste of market imposition and cultural loss. I find it odd that it has become the first choice for friend and family gatherings, along with dip sauces that share almost the same origin.
That is why, at home, we try to practice what we preach by offering snacks made with cheese and boiled breadnut (fruta de pan), for example. Most of our guests do enjoy these snacks. They usually talk about how long it has been for them since the last time they ate breadnut, and about how they remember snacking on it at their parent’s or grandparent’s homes in the countryside.
This is how local food is being displaced by the “not-so- nutritious” industrial type. Additionally, and without a question, the less we eat our local food, the more we lose some of our identity, of our cultural heritage. That is why it is fundamental to value biodiversity in Panama, especially the type that feeds us, since it comes with a high nutritional value.

“Memory is the most important seed” is the cry of the members of the Red en Defensa del Maíz (Maize Defense Network, Mexico).

Let’s move on and talk about the caimito.

Photo: Forest and Kim Starr / CC BY 2.0

Every first Wednesday of the month, the Smithsonian Research Institute hosts a public lecture (free admission). Scientific experts are invited to share the results of their researches in the different programs of the Smithsonian Institute (Panama). This institute, if I may say, is the world’s most renowned tropical studies center nowadays. These lectures provide an extraordinary opportunity for the public. A fair and most needed way of “giving back” in the form of valuable information. I highly recommend attending one of these lectures. Please contact tejadas@si.edu for more information about the monthly schedule.
Dr. Ingrid Parker was the guest speaker for August. Dr. Parker is a professor at the University of California, and an associate researcher at the Smithsonian Institute She has been studying the caimito (Chrysophyllum cainito) in Panama for over ten years. The caimito is a tree native to tropical rainforests in the American continent. It can grow up to 20 meters, and it is commonly planted as a fruit tree in rural areas. There are different names for the caimito, as used on the different regions where it grows: cainito, cayumito, star apple, golden leaf tree, abiaba, pomme de lait, estrella, aguay…
Dr. Parker was kind enough to share the 2016 report she submitted to the Ministerio del Ambiente (the Ministry of Environment of Panama). It is important to say that all these biology researches require a permit and the subsequent submission of a report. I will try to summarize this report.
“The process of domestication is understudied and poorly known for many tropical fruit tree crops,”* according to Dr. Parker. “Ours is the first study about the process of domestication of the caimito tree.”

Photo: Forest and Kim Starr / CC BY 2.0

She conducts her research in the area of Camino del Oleoducto (also known as Pipeline Road, Parque Nacional Soberanía), Parque Natural Metropolitano, and Camino Viejo de Gamboa (also known as Old Gamboa Road), and in Ciudad del Árbol (City of Trees). On each of these sites, the researcher and her assistants conduct a tree census and monitor the growth and survival of these trees. They also record any predation problems affecting the trees. The researcher strongly states: “We do not cut down any trees.”
“In July 2009, we transplanted seedlings of 64 different genotypes in two of the project’s plantation sites in Ciudad del Árbol, in collaboration with Universidad de Panamá and the Autoridad del Canal.” Ciudad del Árbol is located near Chilibre, in Parque Nacional Chagres. Francisco Abre is the field coordinator for this project and her main collaborator. “Every six months, we check the growth of the seedlings, and we clean the place where they are planted in order to remove the paja canalera [invasive Saccharum spontaneum],” added the biologist. She also mentioned that some of the trees have grown up to sizes above 8 meters.
I always find it very interesting to learn about the origin of the food we eat. For example, the pixbae or pifá (peach palm), has been consumed in tropical areas of Latin America long before the arrival of Christopher Columbus. It comes from the Amazon basin region, and it was the indigenous people who allowed for the spreading of this plant to other areas in Central and South America.
That being said, where does the caimito tree come from? The most common argument is that it comes originally from the Antilles. However, Dr. Parker’s research, conducted with the help of her collaborators, includes genetic studies which might reveal that the origin of the domesticated caimito could actually be Panama.
Dr. Parker has found that cultivated trees grow taller and have more pulp than those growing in the wild. “The pulp of cultivated fruits is less acidic; also, the pulp has lower concentrations of phenolics and higher concentrations of sugar. The seeds are larger and more numerous and are less defended with phenolics [phenolic compounds] in cultivated than in wild fruits. Overall, we found a clear signature of a domestication syndrome in the fruits of cultivated caimito in Panama,”* says Dr. Parker.

Photo: Forest and Kim Starr / CC BY 2.0

“We tested the hypothesis that the caimito tree is native to southern Mesoamerica, and that it was domesticated in Panama, [from] several wild populations. Its subsequent migration to northern Mesoamerica and the Antilles was caused by human action. This means that it is extremely important to study the caimito tree in Panama, and keep its germplasm here.” This proves how important the findings of their work in Ciudad del Árbol are.
“The caimito is part of the natural food resources of indigenous people in Panama. Just like other fruits, just like the jobo (yellow mombin) or the mangostín (ambarella or Tahitian apple), we are losing these edible species in Panama. Our research contributes to a better understanding of the caimito and its different varieties (both cultivated and wild). Understanding the domestication patterns and processes serves in the development of crops and the conservation of agricultural biodiversity. The caimito is also used for reforestation projects with native species,” says Dr. Parker.
She also mentioned in her August lecture for the Smithsonian that: "It makes me sad to see how we can go to a supermarket here in Panama and buy an apple that has been grown in Washington, but many people here do not know what a caimito, a fruit that grows right here in Panama, is.” We need to start paying attention to this.
Her work has been the base of relevant scientific papers, published in collaboration with colleagues. These publications can be found in renowned scientific magazines such as Economic Botany, American Journal of Botany, Ecology and Evolution, and soon in Applications in Plant Sciences. The abstracts of these publications are included on the report Dr. Parker submitted to the Ministerio del Ambiente.
Her work is a valuable tool, and her interest in sharing this information with the general public is admirable, to say the least. I hope to taste and enjoy caimito this upcoming season (September to May). This time, fortunately, with a better understanding of the caimito tree and fruit.

* References: 

-“Domestication Syndrome in Caimito (Chrysophyllum cainito L.): Fruit and Seed Characteristics”. https://repository.si.edu/handle/10088/21162, as published on Economic Botany. -“Domestication of the neotropical tree Chrysophyllum cainito from a geographically limited yet genetically diverse gene pool in Panama”. https://repository.si.edu/bitstream/handle/10088/22026/stri_Parker_2014_... equence=1&isAllowed=y, as published on Ecology and Evolution.