What disease is this? How I handle it?

white cotton growth resemble like powdery mildew. use fungicide and also remove uneffected plant parts

Thanks a lot for your quick answer. 🤗

salut c'est La Fumagine

Powdery Mildew at few of the leaves and the fruit.

Wlc to plantix, Agree with Sali .sir... Tnx

Hi Tutus Kurniawan ! From the pic uploaded by you I believe that this is not Powdery Mildew , it is Sooty Mold, as I can see the blackish growth on leaf. Sooty mold is the fact that it can deeply penetrate whichever surface it’s growing on, and in return, it makes it harder to remove. On other hand Mildew only grows on the surface. You can use Copperoxychloride or any other fungicide to manage it. Thanks for visiting Plantix community

It isSooty Mold andPowdery Mildew click on blue link to get more information and management. Thanks

There's also a sign of some sort of Citrus Scab on the fruit. Black covering on leaves are outer dust particles deposited for a long time. These might be not any spores of Sooty Mold.

To all, thank you very very much for your suggestion and solutions. 🙏🙏🙏

Hi! Your plant is with Fumagina (this black fungus) and likely to have Cochonilha-farinhenta (white dots) .. Mineral oil or neem oil helps in controlling the pest. For the fungus, milk solution controls, but it is essential to control the pest to eliminate the fungus once and for all.

Hi, i think it's Cochenille Noire des Agrumes and Oïdium

Sooty Mold

Thanks for your support Sunil Sharma ji

Thanks Juliane - Fitocon | ManejeBem for your upvote

Embun tepung dan embun jelaga

Tutus Kurniawan You can pls press on the bulb that solved your question.

Dear Tutus Kurniawan Pls press on the comment that solved your question. 😅