Homegrown Squash

squash_landin

These heirloom varieties of squash are the literal fruits of my springtime obsession with Cucurbits (the gourd family – almost 1000 species of zucchini, pumpkin, watermelon, cucumber, etc).

This obsession grew thanks to Dr. Lori Shapiro who knows the coolest facts about squash! For instance, before domestication, wild gourds contained bitter toxins. Only megafauna like mammoths could ingest and disperse the seeds of these protected fruits (1). In the Americas, early hunter-gatherers used dried gourds as floats for fishing nets and to hold food and water. They also used fresh wild gourds for the medicinal properties of the bitter compounds (2). The wild gourd (Cucurbita pepo) was the first plant domesticated in the Americas, and the first agriculturalists likely grew them for their nutritious seeds rather than the bitter flesh. Thanks, Lori!

  1. Kistler, L., L.A. Newson, T.M. Ryan, A.C. Clarke, B.D. Smith, G.H. Perry. 2015. Adaptive domestication in squashes and gourds. Proceedings of the National Academy of Sciences, 112 (49) 15107-15112.
  2. Hart, J.P., R.A. Daniels, C.J. Sheviak. 2004. Do Cucurbita pepo gourds float fishnets? American Antiquity. 69(1) 141-148.

 

Advertisements

An Apple a Day

Landin_apples_web

I grew up in the great apple-producing state of Michigan. If you haven’t been to an apple cider mill during October in the mitten state, you are missing out on one of the great joys of life.

Thousands of apple varieties grew in agricultural fields when nation’s founders declared independence. Today, 80% of that diversity is gone and with it, the genetic variation that can save apples from pests, weather, and disease.

Santayana said, “Those who cannot remember the past are condemned to repeat it.” The consequences of low crop diversity were felt during the Irish potato famine in the 1840s which caused the death or emigration of a quarter of Ireland’s citizens. A pathogen entered the potato fields and spread. Since the potatoes were genetically identical, a disease that affected one could infect them all.

Today, cost and transportation constraints benefit massive agricultural operations. The efficiency of monocultures, though, threatens our food and our health. To fight off disease in genetically-similar apples, we turn to pesticides. Apples are continually cited as worst offenders for chemical coatings (fyi, the American Chemical Society recommends a baking soda solution for washing). Today, about half of apples grown in the U.S. are Red Delicious (despite tasting like wood pulp).

Consider trying some local heritage apple varieties. Apple season starts in August!

P.S. An informative Smithsonian blog post about heritage varieties of apple includes a reference to an apple sleuth who lives just down the road from me!

Golden Protector

landin_marigold_web

I’ve always planted marigolds among my garden. I’ve heard these orange beauties have protective properties against herbivores. Is it true?

Hmm. Most researchers have found properties released from marigold roots inhibit bacteria, fungi, and/or nematodes (although this is extremely variable, depending upon the part of the plant used, how the marigolds are grown, and the pest species tested).

Most interesting sidetrack from my search… some research shows inhibition of Plasmodium, the microscopic organism that causes malaria (1).

Thanks to Charlie O’Shields of DoodleWash for the #WorldWatercolorMonth inspiration.

  1. Pankaj Gupta & Neeru Vasudeva (2010) In vitro antiplasmodial and antimicrobial potential of Tagetes erecta roots, Pharmaceutical Biology, 48:11, 1218-1223

Purring Predators

flea_byJMLandin

As agriculture took hold in Middle Eastern societies about 10,000 years ago, archeological evidence of cat domestication appears. When humans began storing grain, any rodent-killing animal was a benefit. But the presence of cats didn’t spread along with agriculture. Egyptians may have revered cats, but other civilizations used weasels or snakes to limit mice. In the painting “Lady with an Ermine” by Leonardo da Vinci, the weasel may symbolize purity or the young woman’s last name (similar to the Greek word for ermine). With all due respect, however, I think the animal may have just been the lady’s pet; weasels were more common pets than cats at that time.

ermine

Cats may have been popular in Egypt during the heyday of the Roman Empire, but Greeks and Romans kept weasels as their rodent-killing pets. Cats joined European families around the fourth century but were relatively uncommon until the 1600s (1).

Nowadays, of course, cats are popular pets and internet memes. Their omnipresence is also a major cause of concern to ecologists and bird lovers. In a 2013 research article, Loss et al. estimated our purring pets (and their feral cousins) kill about 2.5 billion birds and 12 billion rodents each year in the U.S. alone (2).

P.s. The adorable cat who posed for this painting is our own 18-year old feline princess, Flea. She’s killed exactly one bird in her life, a fledgling finch who accidentally flew into her mouth. Flea didn’t even bite down; the little bird panicked to death.

  1. The Oxford Handbook of Animals in Classical Thought and Life. G.L. Campbell. 2014. Oxford University Press.
  2. Loss, S.R. et al. 2013. The impact of free-ranging domestic cats on wildlife of the United States. Nature Communications 4:1396.

A Raspberry’s Worst Nightmare

fruit_fly3

With all the beautiful berries available now, I’ve been seeing more fruit flies hanging around the kitchen. Annoying? Yes. Ruining my strawberries? Nope. Fruit flies lay their eggs on damaged or rotting fruit. So they’re only interested in the pieces that are going bad. I’m ok with that.

But consider a fruit fly who lays her eggs on fresh fruit. She’d have the agricultural community freaking out. Just imagine the risk to berry crops. Actually, you don’t have to imagine because scientists have already done the calculations for you: it’s potentially $2.6 billion of risk (1).

Evolution has already dealt this stunning set of cards to Drosophila suzukii, the spotted-wing drosophila (2). The females have an ovipositor (the anatomical structure that deposits eggs) that looks like a serrated knife. Unlike the common fruit fly in your house, this species’ egg-laying parts can cut through the skins of raspberries, strawberries, blueberries, cherries, and grapes.

Want to learn more about the spotted-wing drosophila? IFAS at the University of Florida has a great info page on the little beastie (with horrifically gorgeous pictures, by Martin Hauser, of that ovipositor – if you haven’t seen fruit fly genitalia yet, you are missing out).

p.s. Thanks to Dr. Nadia Singh for introducing me to Drosophila suzukii.

  1. Walsh, Douglas, M. Bolda, R. Goodhue, A. Dreves, J. Lee, D. Bruck, V. Walton, S. O’Neal, F. Zalom. 2011. Drosophila suzukii (Diptera: Drosophilidae): Invasive Pest of Ripening Soft Fruit Expanding its Geographic Range and Damage Potential. Journal of Integrated Pest Management. 2(1): G1-7.
  1. Atallah, L. Teixeira, R. Salazar, G. Zaragoza, A. Kopp. 2014. The making of a pest: the evolution of a fruit-penetrating ovipositor in Drosophila suzukii and related species. Proceedings of the Royal Society B: Biological Sciences, 281 (1781)