# Disease in Vineyard: best indice? **URL:** \ **Category:** General Ag Questions/Troubleshooting\ **Created:** [July 27, 2023, 12:27pm UTC](https://community.pix4d.com/t/disease-in-vineyard-best-indice/27268 "2023-07-27T12:27:08Z")\ **Posts on this page:** 14\ **Page:** 1
**Author:** ![lowaltitude](https://avatars.discourse-cdn.com/v4/letter/l/f19dbf/32.png) [@lowaltitude](https://community.pix4d.com/u/lowaltitude)\ **Post date:** [July 27, 2023, 12:27pm UTC](https://community.pix4d.com/t/disease-in-vineyard-best-indice/27268/1 "2023-07-27T12:27:08Z")
I’ve surveyed a particular vineyard plot in which I know there is a strip of yellowing vine, due to disease. I have processed the plot through various indices including NDVI, GCI, ReCI and NDRE but the location of the stressed canopy is not really showing. Other than already known lower canopy cover (and hence soil showing) I can’t see anything specific that I would call out, if we didn’t already know there was a problem. EDIT: the GRAPES are showing the yellowing, which is a disease indicator, believed to be Powdery Mildew. I would expect to pick this up on MS. Is there a better / recommended index that I could use? In the screen capture below, the known issue is roughly in the box. Note that the red colour in the map index is soil. I’m looking at the vine (green) to try and detect a variation in the reported colour and index value. It would be really useful to be able to get the index value for a map point selected by the mouse… Any advice would be hugely welcome! ![Screenshot 2023-07-27 at 13.23.29](https://global.discourse-cdn.com/pix4d/original/2X/4/4fdf936d2b13f1129cf26204bdcb411826e35caa.jpeg) ---
**Author:** ![Julius\_Petri](https://sea2.discourse-cdn.com/pix4d/user_avatar/community.pix4d.com/julius_petri/32/4592_2.png) [@Julius\_Petri](https://community.pix4d.com/u/Julius_Petri)\ **Post date:** [July 27, 2023, 12:32pm UTC](https://community.pix4d.com/t/disease-in-vineyard-best-indice/27268/2 "2023-07-27T12:32:26Z")
How does the RGB imagery look like at this place ? ---
**Author:** ![lowaltitude](https://avatars.discourse-cdn.com/v4/letter/l/f19dbf/32.png) [@lowaltitude](https://community.pix4d.com/u/lowaltitude)\ **Post date:** [July 27, 2023, 12:36pm UTC](https://community.pix4d.com/t/disease-in-vineyard-best-indice/27268/3 "2023-07-27T12:36:16Z")
Good question, I’ll run the RGB now. Normally I only run TIFF for multispectral. ---
**Author:** ![lowaltitude](https://avatars.discourse-cdn.com/v4/letter/l/f19dbf/32.png) [@lowaltitude](https://community.pix4d.com/u/lowaltitude)\ **Post date:** [July 27, 2023, 12:53pm UTC](https://community.pix4d.com/t/disease-in-vineyard-best-indice/27268/4 "2023-07-27T12:53:35Z")
![Screenshot 2023-07-27 at 13.52.25](https://global.discourse-cdn.com/pix4d/original/2X/5/5e3eb2a8f65bfacb6d89490ab44362bc85d2612b.jpeg) It’s difficult to see it clearly but you can start to see it here. ---
**Author:** ![lowaltitude](https://avatars.discourse-cdn.com/v4/letter/l/f19dbf/32.png) [@lowaltitude](https://community.pix4d.com/u/lowaltitude)\ **Post date:** [July 27, 2023, 12:55pm UTC](https://community.pix4d.com/t/disease-in-vineyard-best-indice/27268/5 "2023-07-27T12:55:00Z")
Zoomed out, RGB ![Screenshot 2023-07-27 at 13.54.29](https://global.discourse-cdn.com/pix4d/original/2X/4/48469e944e7bab3b5bfe2695f92b41ff5fb435b6.jpeg) ---
**Author:** ![lowaltitude](https://avatars.discourse-cdn.com/v4/letter/l/f19dbf/32.png) [@lowaltitude](https://community.pix4d.com/u/lowaltitude)\ **Post date:** [July 27, 2023, 1:50pm UTC](https://community.pix4d.com/t/disease-in-vineyard-best-indice/27268/6 "2023-07-27T13:50:18Z")
Adding to this: I found a ‘Powdery Mildew Index’ with the following formula: PMI = (R520-R584)/(R520+R584)-R724 So think for Pix4D that would translate roughly as (Green- Orange?!)/(Green+Orange?!)-Red Obviously ‘orange’ is an issue…any ideas folks? ---
**Author:** ![Julius\_Petri](https://sea2.discourse-cdn.com/pix4d/user_avatar/community.pix4d.com/julius_petri/32/4592_2.png) [@Julius\_Petri](https://community.pix4d.com/u/Julius_Petri)\ **Post date:** [July 28, 2023, 7:27am UTC](https://community.pix4d.com/t/disease-in-vineyard-best-indice/27268/7 "2023-07-28T07:27:06Z")
Those are the wavelengths for the m3m bands: ![image](https://global.discourse-cdn.com/pix4d/original/2X/4/44af13dcada442a8445edb600a0cde92bbc7d720.png) So for R520 you could try with the Green band, but its still a couple of nm off. ---
**Author:** ![Julius\_Petri](https://sea2.discourse-cdn.com/pix4d/user_avatar/community.pix4d.com/julius_petri/32/4592_2.png) [@Julius\_Petri](https://community.pix4d.com/u/Julius_Petri)\ **Post date:** [July 28, 2023, 7:29am UTC](https://community.pix4d.com/t/disease-in-vineyard-best-indice/27268/8 "2023-07-28T07:29:07Z")
In general for this kind of dataset, you biggest enemy is the area between the rows, because it will throw of the complete index visualization. You can try with MagicTool to detect it, and then Trim it away so that only the data from the actual rows will be left for analysis. The next version of PIX4Dfields will have tools to help with that. ---
**Author:** ![lowaltitude](https://avatars.discourse-cdn.com/v4/letter/l/f19dbf/32.png) [@lowaltitude](https://community.pix4d.com/u/lowaltitude)\ **Post date:** [July 28, 2023, 8:21am UTC](https://community.pix4d.com/t/disease-in-vineyard-best-indice/27268/9 "2023-07-28T08:21:26Z")
Perfect, thank you! ---
**Author:** ![lowaltitude](https://avatars.discourse-cdn.com/v4/letter/l/f19dbf/32.png) [@lowaltitude](https://community.pix4d.com/u/lowaltitude)\ **Post date:** [July 28, 2023, 8:23am UTC](https://community.pix4d.com/t/disease-in-vineyard-best-indice/27268/10 "2023-07-28T08:23:06Z")
I’ve got around that by creating a boundary which has sub-boundaries per row. It’s time consuming but does remove the ‘in between’ areas, focussing the index on just the vine. ---
**Author:** ![Timbang\_Deli](https://sea2.discourse-cdn.com/pix4d/user_avatar/community.pix4d.com/timbang_deli/32/356_2.png) [@Timbang\_Deli](https://community.pix4d.com/u/Timbang_Deli)\ **Post date:** [August 3, 2023, 2:01am UTC](https://community.pix4d.com/t/disease-in-vineyard-best-indice/27268/11 "2023-08-03T02:01:36Z")
I would suggest to take sample on the field where the area got stressed due to disease. Then you overlay with indices (NDVI, NDVIRE, LCI, etc) and play with threshold value indices (classification). Hope you find correlation with that. ---
**Author:** ![harry](https://avatars.discourse-cdn.com/v4/letter/h/f6c823/32.png) [@harry](https://community.pix4d.com/u/harry)\ **Post date:** [June 30, 2024, 9:39am UTC](https://community.pix4d.com/t/disease-in-vineyard-best-indice/27268/12 "2024-06-30T09:39:59Z")
Hi Julius, was there any update on this? Would love to know ---
**Author:** ![Jose.Arnaudo](https://sea2.discourse-cdn.com/pix4d/user_avatar/community.pix4d.com/jose.arnaudo/32/5966_2.png) [@Jose.Arnaudo](https://community.pix4d.com/u/Jose.Arnaudo)\ **Post date:** [July 1, 2024, 11:37am UTC](https://community.pix4d.com/t/disease-in-vineyard-best-indice/27268/13 "2024-07-01T11:37:41Z")
Hi, We introduced a new Zonation tool that might help you identify zones within the rows. If the field is rather flat, you can try the following: - Process the imagery using Accurate processing. - Go to Operations, Zonation, and choose the DSM layer. - Set the histogram so as to only leave pixels that are of vineyard rows ![image](https://global.discourse-cdn.com/pix4d/original/2X/e/e1efa772ae21dc24f502afc48b1a75d4f199d16e.png) - Click continue. - Here you can: - Set 1 zone and save the Operation… - Export the Operation as Shapefile. - Import it again as boundary, now you can use it to trim the Index layer. I hope this makes sense. You can watch a similar workflow to identity weeds on fallow: [Weeds on fallow detection (Green on Brown) - PIX4Dfields](https://support.pix4d.com/hc/en-us/articles/17246143431325) ---
**Author:** ![lowaltitude](https://avatars.discourse-cdn.com/v4/letter/l/f19dbf/32.png) [@lowaltitude](https://community.pix4d.com/u/lowaltitude)\ **Post date:** [July 1, 2024, 12:30pm UTC](https://community.pix4d.com/t/disease-in-vineyard-best-indice/27268/14 "2024-07-01T12:30:15Z")
Thanks Jose, I’ll try that!