It looks like this

where are you.. big city name ...

save your money on bug spray.. it most likely isnt ...

can we see a pic of the whole plant ...

all white tissue on a plant is weaker than any other color tissue ... it is a net minus for plant health..

it burns in too much sun ... lets say it has no uv protection .. and burn causes brown tissue.. and beyond ...

its doesnt move water in the leaf like green tissue.. leading to burn ...

if i had that plant it would NEVER see direct sun.. ever ...

and a big swath of white tissue is the worst ... i would probably just cut the leaf off if i was sure there are other leaves with more green to take over ...

in the hosta world.. those who grow seeds. get these all white plants ... we call them terminal whites .. because they can not photosynthesize without green tissue .. so they all end up dying .. sooner or later ..

same idea here.. as to this single leaf ..

all that said.. your leaf does have green tissue.. and that will continue to process light into energy.. if you dont have more leaves to do the job .. if you just want to cut off the ugly white part.. just so you dont have to look at it .. go for it ...

and finally.. slathering on any kind of goos or oils.. or sprays onto white tissue.. often leads to more problems .. so unless you actually find a bug that needs to be taken care of .. in such volume that you cant just pick a few off .. i would NEVER SPRAY ANYTHING ON THIS PLANT .... for fear of causing more harm than any good ... that it might accomplish ...

lets try not to love it to its detriment...

lets see the whole plant ..

ken