Skip navigation
1 2 3 4 5 6 Previous Next

Seeking nightshades in South America

82 Posts tagged with the solanaceae tag

Sierra de Santa Barbara

Posted by Sandy Knapp Feb 16, 2012

Another wonderful day exploring and hunting the wild solanums of Argentina! Some might think we were a bit crazy – but not as crazy as the chaps we met up in the puna near the dunes a couple of days ago (forgot to write about them) who were traversing Argentina on motorbikes from Tierra del Fuego to the Bolivian border – 5000 km each way!! - in 15 days; this definitely makes botanists look sane.


Today we went to a small mountain range in the eastern part of the province of Jujuy – specifically to look for a plant known only from its type specimen (Solanum fabrisii), to see if we could recollect it. We did – it turns out to be the same (we think) as a species someone described earlier (Solanum glandulosipilosum – great name); this makes it a synonym – not a mistake, but a different interpretation of the evidence to hand (a story for another time!). On the way – we saw spectacular scenery, this huge canyon had no roads or trails leading to it – tierra incognita – or so it seemed to us.


Sierra de Santa Barbara_DSC_6937 (Mobile).JPG


Today has made us both think about why field work is so important for the science we do at the Museum; not only do we find new things and sort out who is who, but field work is essential for looking at the natural variation of plants in the wild. Take, for example, a species we saw all day today – Solanum “aloysiifolium” (in quotes because we are not quite sure what its correct name is yet!). We saw this plant all over the Sierra de Santa Barbara (and have before today), but each time it looks a little bit different – just like individual people look different in small details. Big leaves, small leaves; white flowers, purplish flowers….. This is variation – the very stuff of evolution. Seeing this species in many different places, and looking a little bit different every time lets us calibrate how we are defining species, and shows just how much variation there is in nature. Doing this together, all three of us can discuss what matters, what we see (and we all do see very different things!) and just how we might deal with the complexity of what we observe. Collecting specimens that we will later look at carefully in the herbarium will let us connect the differences we see in the field with the data we take from pressed specimens and from DNA sequences to come to decision about what constitutes this particular species – is this one species or three or seven?


aloysi_DSC_6962 (Mobile).JPG



Collecting a species more than once is definitely NOT a waste of time! It does, however, mean we have more plants to dry every night on Gloria’s field dryer – here set up in our hotel in the town of Libertador   General San Martín; we set it up every night and it works a treat. Looking for electric sockets in tiny hotels in villages in out of the way places can be a challenge though…..


estufa_DSC_6996 (Mobile).JPG


First five days

Posted by Tiina Feb 15, 2012

Finally internet connection! Five days in the field and five more to go!


Day 1 – Sandy:


We set out from Cordoba – Tiina, Gloria and I, plus our wonderful driver Leonardo – and headed west, to Catamarca. Along the way we passed some amazing salt flats – huge expanses of flat salty land; when we stopped to take a picture, we found our first SolanumSolanum euacanthum – whose fruits burst open to reveal black seeds when they were touched! We press the plants on a back of the truck, Gloria has a very efficient system.


euacanthum_DSC_5546 (Mobile).JPG


pressing_DSC_5549 (Mobile).JPG


We carried on, looking for a particular species called Solanum mortonii – we have no collections of this in the Museum, and I was particularly interested to see it. Once place we passed it right by, but then, going up a beautiful valley to a village called Los Angeles, we found it all over! It turns out that Solanum mortonii is partial to steep rocky slopes, and has a much wider distribution than people previously though. Our find of the day though was an enigma called Solanum reductum.


reductum_DSC_5677 (Mobile).JPG


We’ve never known what this plant really was and who it was related to, but finding it in the wild made it all clear! It is clearly a relative of another enigmatic species only described a few years ago by our colleague Lynn Bohs from Bolivia (Solanum clandestinum). We decided to spend the night in Los Angeles, as a policeman told us there was a hotel there, but once there, we found it wasn’t open yet – a long trip back down the valley at the end of a long but really productive first day!!


LosAngeles_DSC_5652 (Mobile).JPG


Day 2 – Tiina:


More mysteries solved! Solanum salicifolium seems to be one large variable species. We observed amazing variation in leaf shape in local populations, even within individuals. The picture tells it all – one branch can have simple, entire leaves as well as deeply pinate ones! Having observed this we are convinced that Solanum incisum, including all its varieties, are synonyms of Solanum salicifolium.




Lesson of cultural importance of the day was Gauchito Gil, a local Robyn Hood legend who stole from the rich to defend the poor. As we were driving along, we saw shrines build for Gauchito everywhere in the north, often under trees with red flags hanging from the branches.

Guachito_DSC_5887 (Mobile).JPG


Day 3 – Sandy:

The search for solanums continues apace….. we slept in a wonderful hotel that was someone’s house – full of old photographs and memorabilia. Our goal was the Cuesta de Randolfo, an area of puna – high Andean vegetation composed mostly of grass and low shrubs. I continue to be amazed at the variety of landscapes that we have seen in Argentina – an amazing country. To get to the Cuesta de Randolfo we had to drive across several rivers but once there – how incredible! We stopped to collect a species I was interested and suddenly Gloria yelled “Solanum chamaesarachidium!!!” She had found a very rare, tiny annual plant growing in the sand right by the truck. This entire plant is only about 5 cm in diameter and the flower is minute – what is that mite doing in there? Wow.

chamaesarachidium_DSC_6073 (Mobile).JPG


Higher up, there were huge sand dunes – a strong wind blows here much of the time and the sand collects in various valleys.


dunas_DSC_6261 (Mobile).JPG


Here we were in real puna, and much to my excitement saw the rarest of the South American camelids – vicuñas. I had seen them once before in Peru, but there they ran away – here in Cuesta de Randolfo they just stared.

vicunas_DSC_6234 (Mobile).JPG


What a day – vegetation like I have never seen before and wonderful plants – this is what plant collecting and field work is all about…..  we spent too long up high though, and had to leave one place we wanted to visit out though in order to meet our colleagues in Tucumán – it was well worth it.


Day 4 – Tiina


Today we found Solanum annuum, Solanum glandulosipilosum and a mysterious other Solanum species! Solanum annuum is a tiny plant at 3000 m elevation, it’s hard to find but we found it! A mysterious species was found just nearby - it has very distinct clusters of hairs alongs its stem. This plant needs to be looked at properly when we get back as we don’t know what it is at the moment!



Further down the valley in Tafí we found Solanum glandulosipilosum – a distinct species of the Morelloid Solanum with glandular hairs and a distinct smell of insecticide! Of course it started to rain hard by this point… We just had to keep working, but taking photos became difficult! Dried boots on the plant dryer over night.




In the evening we met up with our Chinese colleagues in Tucumán, and had great dinner with much to talk about. They are heading back after a two week visit in Argentina with a 30 hour flight ahead of them! Durig their first trip to Argentina they have had a chance to see Patagonia in the south, Iguazú falls in the east, and the Andes in the north – what a great trip!


Day 5 – Tiina


Good luck continues – today we found another plant that has remained a mystery to us. Having seen Solanum collectaneum in the wild, growing along in montane forest edges in Tucumán, it seems a very close relative of Solanum aloysiifolium, if not the same thing. Another thing to investigate further back in London. The fruits are so cute: they are tiny with a fantastic colour of deep dark blue-purple!


collect-aloysi_DSC_6682 (Mobile).JPG


Tomorrow advancing further north, towards the National Park of Calilegua!



The past couple of days have been full of discovery - in the herbarium! Cordoba is a great centre for Solanaceae research, the great solanologist (person who studies nightshades - so wonderful they have their own profession) Armando Hunziker worked here until he sadly died in 2001. He was the director of the institute for 52 years, incredible dedication. His portrait hangs behind where I am working - I hope he approves.


The cupboards are full of treasures - new records for Argentina for little known species, lots of specimens of species that are endemic to Argentina and of which we have not a single collection in London - this is why working with colleagues in other institutes like ours is so incredibly rewarding. Highlights have been many specimens of Solanum endodenium - which we hope to see in the next week - with dark purple flowers with a green "eye"; a duplicate of a type specimen that I thought had been destroyed in the bombing of Berlin in the 1940s, oh and the list goes on. Tiina is figuring out her very complicated plants over in the next room - we keep popping back and forth to trade ideas and questions.


We have been looking at specimens not only for databasing and recording for future work, but more urgently to see where we need to prioritize the trip in order to see as much as possible. We will certainly find surprises though, in the Andes solanums are everywhere, and a beady eye is a must while travelling. Our route will take us to 3000 m elevation and through some fantastic places - can't wait!!




Cordoba, Argentina....

Posted by Tiina Feb 8, 2012



I am here at last; flying over the Andes this morning from Santiago in Chile was amazing - beautifully clear and I could see all the glaciers and snow-capped peaks. Not much snow now because it is summer here....


Cordoba is a beautiful town, a brilliant mixture of old colonial and new. The University where the herbarium is located is near the centre of town, we went over there this afternoon to have a look around. They are experiencing a heat wave in Cordoba - it is approximately 30 degrees and VERY humid! I am catching up on all the adventures Tiina and Gloria have been having last week - I'll had over to her now for the update!




It was great to get Sandy here with us to sort out some issues with Solanum! Like Sandy says, it's extremely hot and humid, which is why we've also had some big storms this week. A few days ago it was raining ice balls - yes I mean ICE BALLS!


I took pictures as proof of how bad it was: we had to mop water from the floor as the roof and windows were leaking in the herbarium! It was a real mixture of ice the size of table tennis balls, and massive rain.


It just goes to show that it's not easy to keep up a museum in tropical countries... While we were busy mopping water from the floor, the storm knocked down a large tree just outside. The sound was tremendous! Gloria and I went out to see the damage afterwards.

IMG_5595 (Mobile).JPG

IMG_5603 (Mobile).JPG

The challenge of the coming days is to fit everything in. We have meetings to talk about our recent results, our work with molecular phylogenetics and taxonomy at NHM, and cytogenetic and taxonomic work here in Cordoba. It's a great chance to throw some ideas around, discuss what we have and plan future work.


We also have to plan the route for our longer trip in the north. We are heading to the big Andes on Friday, to the departments of Jujuy, Catamarca, Tucuman and Salta. There are many species we want to cover, and we can gather localities where to find them from the herbarium and our existing online Solanum database.


During the weekend we did a short 3 day trip around the departments of Cordoba and San Luis and managed to find species which were previously only known from types. The three species we found in the field can now be studied in detail together with the original descriptions to fully understand the species.


Now off to bed, we are gathering strength for what's ahead! Thus far 253 specimens fully databased, c. 400 identified, and more to go!


The big snow got me a bit worried about getting out to Argentina to join Tiina Sarkinen, who has been there for a week working in the herbarium with our colleague Gloria Barboza and her students. But it all looks fine - flight is not yet cancelled and so I am on the way! Hard to imagine laeving this snow and ice behind.


Packing for a long field trip is always a challenge - what to take, what to leave. My house and office have been piled up with the many items needed for field and herbarium work. Camera, plant press, secateurs (for cutting branches to press as specimens), camera, sunscreen, first aid kit - the list is endless!


Because our field trips are not only just about going in the forest to collect nightshades, but also about working with our colleagues in institutions like the Natural History Museum in other countries, I need to take all the bits and pieces for that sort of work as well. I have printed out many annotation slips - small identification chits I will place on the specimens in other collections to indicate my identification of these specimens - they will say I identified this specimen as a particular species on a particular date. This is how botanists leave the evidence of their use of hte specimens.



I have never been to the collections in Cordoba, Argentina before (our first stop), so am really excited to see what I find! I know there are specimens of a species in a group I am currently working with - Solanum mortonii - that I have never seen; we don't have any specimens of this in the NHM collections. Exciting!


I am also looking forward to seeing what Tiina has found in her travels so far - in a strange set of coincidences some Chinese colleagues of mine (see the eggplant blog from 2010) are visiting Gloria in Cordoba as well, so we will have a chance to have a truly global conversation about Solanaceae. One of the great things about working on a particular plant family like the nightshades is that colleagues are everywhere and the spirit of working together is very strong.


So in an hour I will leave for the airport - next post will really be from the field!


Setting the scene...

Posted by Tiina Feb 2, 2012

We all like eating tomatoes and potatoes - what could be better than chips with ketchup ! But did you know tomatoes and potatoes are extremely closely related? Although a red juicy tomato looks totally different to a pale yellow potato, the two plants share much of their DNA.


Potato and tomato belong to a group of plants known as Solanaceae - the nightshade family. In actual fact, they are so closely related they belong to the same genus within Solanaceae, known as Solanum. Tomato is called Solanum lycopersicum L. in scientific latin, whilst potato is known as Solanum tuberosum L.



Other well known species in the group include the bell peppers, chili peppers, eggplants, petunias, and tobacco - yes, incredibly this strongly flavoured plant is related to commonly eaten yummy things! South Americans might know more fruits from the family, such as naranjilla (Solanum quitoense Lam.), or tamarillo (Cyphomandra betacea Sendt.) used for making preserves and juice. If you visit Mexico and indulge in local food culture, you come across another species from the family, tomatillo (Physalis philadelphica Lam.) which is used to prepare salsa for buritos, tacos and tortillas.


Below is a lovely phylogeny of the nighshades which illustrates how the species are related within the family. It's based on a small set of DNA data. It is still not complete as it only includes roughly 30% of all the species in the family. Our aim is to add more species as our research progresses. What you can see is that eggplant, tomato, potato and pepino are really closely related, and tobacco is the furthest relative of them all. Solanaceae_large_phylogeny_SMALL_for_blog.jpg



The nightshades were known to be a group of closely related plants before anybody even knew they are related based on their DNA. This is because all species in the group share a set of morphological characters. Some of these are very obvious such as flowers which are generally stellate, with five corolla lobes, and five stamens. The most clear character that unites the family is seeds. Seeds are small – think of tomato seeds! – flattened, kidney-shaped, and have puzzle-piece shaped cells if looked under a microscope. Most of seeds in the nightshade family have curled embryos. If you are curious, try looking at dried tomato seeds closely! You will see the impression of the curled embryo on the seed quite easily.



Other characters of the nightshade family are more hidden. For example, all nightshades have internal phloem which means that sugars produced in leaves via photosynthesis are transported down to roots inside the water transport system known as xylem. Most plants have an opposite type transport system where sugars are transported outside the waterpipe system.



Anyways, why all this ramble? Well, the thing is that we are about to go hunting for nightshades in the Andes! There are an estimated 4,500 species of nightshades in the world, and large number of these is found in the Andes. These are wild relatives of tomatoes and potatoes and such likes, some weirder than other, some with tubers, whilst other climb trees! There are still species remaining to be described, waiting in the forests and mountain sides for discovery. We will be travelling in the northern part of Argentina and in Peru over the next coming 3 months – our aim is to collect as many species of Solanaceae on our way. This time we are targeting the particularly poorly known species of the Morelloid clade in the genus Solanum, a set of roughly 60 species.


Preparing for the big trip!

Posted by Tiina Jan 31, 2012

Trip preparations have began with full steam! Having prepared and organised our collection permit applications for our trip, I am now focusing on gathering locality information. This means going through all specimens of my target species, which are the Morelloid species of the genus Solanum. These include about 65 species closely related to tomato and potato.





Museum collections can help enourmously in finding these species in the wild. Each museum specimen carries with it some information about the locality the specimen was found in. These localities can aid in finding these species in the wild again, as long as the habitats remain relatively undisturbed. The main reason for going to the field is to get a chance to observe species in their natural habitats, which inturn helps taxonomists like us to fully understand species delimitation - simply put, this means understanding what constitutes a species, and how species differ from each other. Often it is extremely difficult to understand where one species ends and another begins based on old material alone. Imagine standing there with a latin description in one hand ! and a poor quality specimen from 18th century in the other = It's not always so exciting to be a scientist !




Our second aim is to record as many occurrences of any species of Solanaceae in order to study how plant distributions change through time, and how species might respond to climate change in the future. Currently, many species are still only known from less than five specimens. That means we only know less than five populations for these species! This is just not good enough, and more is needed to analyse how species might respond to change - whether this is climate change or change in land use due to increased pressure from growing human population. There are many weeds in the world but majority of species are poorly known endemics that we need to

keep collecting.
1 2 3 4 5 6 Previous Next