What is it? A fruit? If so, is it rotting?

Oh. Or is it the back side of a leaf? If so, looks like a whopping case of scale or mealybugs.

Please post more images, and larger, in this thread. Also some overall views of the plant in question.

Which pesticides have you been trying? What little can be seen appears to be scale, which are not usually controlled by any pesticide.

It certainly does look like Scale. But as said it is hard to get a Proper ID with this picture.
Only certain pesticides work on Scale and only at times when the crawlers are out, which is different for the type of scale and climate. Take or send samples to your local extension service for proper ID. Horticultural Oil if applied correctly will kill scale. Once you have an Id and it is scale get some and follow the directions. And coverage is critical for control with Oil.

Kimmsr...horticultural oil is a pesticide.

Folks, roger appears to be from Singapore. Without knowing what kind of plant this is, I feel a bit handicapped to guess. Does look like one of the scale insects, though. A decent image might give us all a completely different opinion, though.

Missed that Singapore part. I wonder if they have extension services?
Technically anything used to kill a pest is a pesticide, including water.

if they are fuzzy .... wholly aphids ????

as above.. that pic is too small for any real diagnosis ...

ken

Hi friends thanks for sharing.
The Flysheets cover the most common pest and disease problems growers might encounter, and feature comprehensive advice, including what symptoms to look for, typical host plants, diagnosis, control and preventative measures.

Here is a link that might be useful: Rabbit Hutches

I hear those rabbit hutches are radioactive and built with child labor from dug up coffins.

tj