Petiole - leaf area meter & chlorophyll content measurement in a smartphone

Chlorophyll Content

At Petiole we got many requests about a feature to measure chlorophyll content in leaves using smartphone with Petiole. Hence, now we are working on this idea and hope to bring a new product soon.
Would you like to be among the early adaptors and get news about Petiole chlorophyll measurement when this solution will be ready? Leave us your email and we will send you updates as soon as they come.

Features

Accessible Anywhere

In lab, greenhouse or field

Measure leaf area manually at your lab or in a field. Manage each leaf area measurement to find total leaf area and specific leaf area (SLA) without Internet and equipment.

Works Off-line and On-line

Less Than a Second

Measure more plants

Measure specific leaf area faster to make swifter decisions. Petiole gives you information how to calculate leaf area so you can interpret it quickly and act on.

Smart Leaf Area Meter

Time Saver; Money Saver

Helps to be productive

Forget about plant leaf area meter and ImageJ. Or other leaf area measurement software. Petiole makes leaf area calculation and saves your time and finance.

Boost Your Productivity

Science

Front cover of Regulatory Mechanisms in Biosystems

Hrytsak, L. R., Herts, A. I., Nuzhyna, N. V., Cryk, M. M., Shevchenko, V. V., & Drobyk, N. M. (2018).

The influence of light regime on the growth data and pigment composition of the plant Gentiana lutea cultured in vitro.

Regulatory Mechanisms in Biosystems, 9(2), 258-266.

https://doi.org/10.15421/021838

Front cover of Bulletin of Uman National University of Horticulture

Polunina O. V., Maiboroda V. P., Seleznov A. Y..

Evaluation Methods Of Estimation Of Young Apple Trees Leaf Area.

Bulletin of Uman National University of Horticulture, 2018(2), 80-83.
UDK: 303.22: 581.45: 634.11: 634.1.03

https://doi.org/10.31395/2310-0478-2018-21-80-82

Q&A

How to measure leaf area?

What steps should I make to estimate an area of a plant leaf?

Step 1. Download a mobile application Petiole into your smartphone
Step 2. Launch this mobile application
Step 3. Calibrate a camera of your smartphone
Step 4. Put a leaf (or leaves) in front of a camera
Step 5. Point to the leaf and look at leaf area calculation in the screen.
Step 6 (optional). Add the data of specific leaf measurement into leaf area count to calculate total leaf area.
Take a quick look at this 1-minute video and you will see all of these steps.

I cannot calibrate camera. What's wrong?

I am not able to complete the camera setup. Please, help me.

To solve your problem with camera calibration you can try the following steps:

Move or zoom the camera closer to the Calibration Pad. The Pad has to fit as much area within your smartphone's screen as possible.
Setup camera on different smartphone. For technical unclear reasons some smartphones have not enough memory to run calculations in real time mode.

Finally, we have produced four videos about every step of the calibration. Hopefully, this process becomes more clearer with them:
Step 1 - https://www.youtube.com/watch?v=-uU0kiObalw
Step 2 - https://www.youtube.com/watch?v=aHCWkfx80us
Step 3 - https://www.youtube.com/watch?v=m-bGrPqMZQs
Step 4 - https://www.youtube.com/watch?v=K17dcQnD5Xg

How can I buy your Petiole Measuring Stand?

How can I measure leaf area with the same height?

We have different measuring stands for each calibration pad depending on the size of leaves you plan to measure: stand no. 5 (for the smallest leaves), stand no. 7 and stand no. 10 (for middle-size leaves), stand no. 15 (for the largest leaves)

The calculated cost for stand no. 5 is $40 without shipping costs. Other stands are still on the Research & Development stage.
If the price is not affordable for you, there is another option: you can use DIY stands, suggested by our users.

The most popular of them are:

a stack of books,
any box to fix mobile phone on it,
any kind of transparent document file like "stackable tray",
a mobile holder or something like a "lazy arm".

Benefits of DIY stands are obviously cheap price. But they are not a good fit for on-site measurements in field and greenhouse.

Also, we can send you .CAD files of the stand that we are selling, so you can print the stand on 3D printer by yourself.

Where can I get calibration pads?

What calibration pad do I need for leaf area measurement?

At this moment we are not selling calibration pads but you can find Petiole.Pad in the links provided below, and do it by yourself. We have 4 different pads depending on (a) different distances between a leaf and camera and (b) variety of leaves sizes.

Print any of the calibration pads on A4 card paper, cut with scissors and it is ready for use.

For correct and fast leaf area measurement choose appropriate calibration pad depending on a leaf size:
#15 - for big leaves
#10 - for larger-than-average leaves
#7 - for medium leaves
#5 - for small leaves

Team

Maryna Kuzmenko, Ph.D

Chief Executive Officer, Co-founder

Maryna is responsible for legal, finance and PR at Petiole. She works on customer development, scaling the project and establishing new partnerships with educational institutions and business.

Before starting her work on Petiole, Maryna has got extensive legal experience as an assistant of the MP at Verkhovna Rada of Ukraine and also worked at local branch of AXA Insurance as well as Antimonopoly Committee of Ukraine.

Maryna has Ph.D in Business Law (2015) at Taras Shevchenko Kyiv National University, LL.M with Merit in International Commercial Law (2012) at London Metropolitan University and Master’s Degree with Honours in Law (2007) at Igor Sikorsky Kyiv Polytechnic Institute in Ukraine.

She leads the Ukrainian group at Tech London Advocates, the global private network of tech leaders, entrepreneurs and experts.

Maryna contributes her free time to promote Ukrainian literature using technologies at her Literary Agency.

Andrii Seleznov

Chief Technology Officer, Co-founder

Andrii is responsible for all design and technologies at Petiole, including the look and feel of mobile applications, user interface, packaging, as well as new ideas and future initiatives.

His talent in digital technologies has been recognized with the Endorsement of Tech Nation as a Tier 1 Exceptional Talent Visa holder.

Prior to founding Petiole, Andrii has worked on different software development and design projects at international tech companies in Ukraine, USA and United Kingdom.

He earned his Master's Degree with Honours in Geographic Information System (2008) at Donetsk National University in Ukraine.

In spare time Andrii is interested in robotics and palaeontology.

Feedback

I enjoyed using Petiole - it is very intuitive and gave me nice, accurate leaf area measurements. It is always nice when you have technical solutions that work really well! However, my research has shifted directions. I am working much less with leaf-level physiological measurements, and more with large-scale, satellite-based measurements. There are some opportunities I see to use Petiole again - it looks like leaf mass per area (LMA) may drive some of the signal in near-infrared reflectance. - Christopher Anderson, Stanford University
It is applicable and very useful - Adi Wirman, Feedback at Google Play Market
Спасибо разработчикам за приложение! Даже не ожидала, что есть такое, очень удобно проводить измерения, особенно, когда у тебя много листьев. Сначала были проблемы с настройками петиоль.пада, разработчик посоветовал сделать следующие шаги: прижать калибровочный лист к плоскости стола. Важно, чтоб он был ровным; приблизить камеру к калибровочному листу; попробовать другие калибровки №5 №7 №15 и все получилось! - Darya Nectarine, Feedback at Google Play Market
Good, It was what I wanted. - Adauto Ribeiro, Feedback at Google Play Market