Monday, April 1, 2013

Pineapples don't grow on trees!

Today, being April 1st and all, I was going to photoshop two plants together and then "publish" a new species on my blog. Come up with a really creative name, pretend it has some ridiculous medicinal quality that I discovered while experimenting on my cat, and describe its ability to not only transport itself from one place to another by its roots, moving through sandy soil, but also that when the flowers open it moos like a cow. Yeah, big plans. But then you know what? I remembered I didn't have a clue how to use photoshop properly. Maybe I'll learn in time for next year's April Fools :)

Until then, 365 days from now, you can enjoy a (100% true) blog about...pineapples!





Species name: Ananas comosus

Common name: pineapple

Location: Dominican Republic

Pineapples. What to say about pinapples?! Well, the first thing to mention is that they do not grow on trees (you can read all about pineapple-like trees HERE). Pineapples are monocots; they don't have the ability to form wood and so cannot be a tree. Plus, from the first picture you should be able to see that they're more like a shrubby, spiky, rather dangerous-looking plant. This observation would be completely true; some of the people that were on the safari excursion with my mom and myself came away from the "farm tour" with scratches all over their legs from brushing up against pineapple plants. The leaves have razor-sharp spines all along both sides and they can slice through skin with the very lightest of pressure. Definitely a plant to stay away from unless you're wearing pants!

Pineapple plants are native to South America, at least that is the current school of thought. Very little is known about the actual domestication of pineapples, nor what the likely ancestor of a domesticated pineapple actually looks like. What is known is that the domesticated pineapple was introduced to the Philippines and to Hawaii very early on, likely before the days of Marco Polo and the Dark Ages. It seems as if no one could quite figure out how to propagate them, and they were eliminated from the agricultural crops of these locations until their re-introduction. It is said that pineapples were re-introduced in the 1500s to Hawaii by the Spanish, but this is widely disputed. We do know that they were cultivated there by 1720 in "pineapple pits", and a widespread re-introduction in the early 1800s caused them to be (and still are) one of Hawaii's most important export crops beginning in the late 1800s. In the Philippines, it is believed they were introduced sometime in the early 1800s, probably by the same Spanish ship that introduced them to Hawaii, and they have become a staple in rural Filipino life. The leaves contain very strong fibres with a very unusual texture (almost like silk when you run your hand along a garment in one direction and feeling like burlap in the other), and this has been used to make traditional clothing for at least two centuries. Now, pineapples are cultivated in the Philippines (mostly just exported to other areas in Asia and in Australia/New Zealand), Costa Rica (where Del Monte produces all of its pineapples after the breakup of the Pineapple Research Institute in Hawaii), the United States (where Dole still grows a lot of its pineapples), Thailand, and Indonesia.

Pineapples carry a lot of controversy, especially with the methods used to cultivate them. Pineapples are all clones of each other; that's the only way you can ensure the fruit obtained will be the same sweet, juicy pineapple consumers have come to love and expect when they buy pineapples. Unfortunately, whenever you clone a plant you make it unable to evolve resistance to pathogens, and pineapples today are attacked on a daily basis by fungi, bacteria and viruses that have evolved virulence genes against the plants. In order to fight disease, this means pineapple plantations must be sprayed, sometimes upwards of 40 times over the time of fruit development (which is only 6 months), just to prevent disease. The chemicals sprayed on pineapple plantations are incredibly dangerous to the health of the workers on the plantations: every chemical sprayed is carcinogenic, many are organophosphates which destroy the environment and can affect brain development in fetuses, and some are hormone disruptors which can have adverse effects on child development (they have been linked to everything from autism to attention deficit disorder to spontaneous miscarriage, brain cancer and leukemia). These chemicals aren't just dangerous for the health of the workers that spray the fields and work in the fields all day; these chemicals are leached into the drinking water supply and are consumed downstream by everyone in surrounding villages. This is a real problem, and there have been many lawsuits filed against both Dole and Del Monte along with encouragement to solve this problem by working harder to develop different cultivars that are disease resistant. There is some effort underway in pineapple biotechnology, but because of the "bad rap" that genetically modified food has, none of these products have made it to widespread cultivation. Remember, too, that if a chemical is sprayed onto the surface of a food item, it is more than likely incorporated in some way (however large or small) into the food that is consumed. Some food for thought (pun intended).

Pineapple fruit develops in a very unusual way; a way that is not shared with any other fruit commonly consumed worldwide. It is called a "multiple" fruit, because it is a single fruit made from multiple flowers. The entire inflorescence of the pineapple goes into making a single fruit! Each flower must be pollinated, usually by bees or hummingbirds, and then all at the same time the flowers mature into the pineapple. The actual pollination process can take from 20 to 24 months! That's two years just to get the beginning of a pineapple fruit. That gives me a whole new appreciation for my pineapple. After all of the flowers have been pollinated, the fruit takes another six months to become fully mature. In the third picture, you can see some of the flowers emerging from the inflorescence. Unfortunately, this entire process is actually detrimental to pineapple production since flower pollination implies seed production. No one wants to be eating seeds in their pineapple! For this reason, pollinators of the pineapple plants have been banned from import by the Hawaiian islands, to prevent unwanted seed development. If no pollination occurs, the fruit still develops but just no seeds are formed. The pineapple is said to be a "mathematical" fruit; the flowers are arranged in two spirals around the inflorescence stalk, with one spiral going each direction. If you count the number of flowers in a spiral one direction it's 8, and the other is 13. This means that the pineapple is an example of a fruit in nature that displays the Fibonacci number sequence. Neat!

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