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 Solanum – Solanum 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.

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.

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!!

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.

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.

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

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.

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!

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

Sandy:

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!

Tiina:

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.

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!

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.

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.