Queste piante sopravvivono senza molta acqua.

Queste means these and agrees with piante, which is a feminine plural noun.

• questa = this, feminine singular
• queste = these, feminine plural
• questo = this, masculine singular
• questi = these, masculine plural

Since piante is plural and feminine, queste is the correct form.

The singular form is pianta (plant), which is feminine. Many Italian nouns ending in -a are feminine, and their plural usually changes to -e:

• la pianta = the plant
• le piante = the plants

So piante is the plural of a feminine noun.

Sopravvivono is the third person plural of the verb sopravvivere (to survive) in the present tense.

Here is the relevant part of the conjugation:

• io sopravvivo = I survive
• tu sopravvivi = you survive
• lui/lei sopravvive = he/she survives
• loro sopravvivono = they survive

Since the subject is queste piante (these plants), Italian uses the they form: sopravvivono.

Because Italian usually does not need subject pronouns when the verb ending already shows who is doing the action.

• Sopravvivono already means they survive
• Queste piante sopravvivono = These plants survive

You could say loro sopravvivono, but that is usually unnecessary unless you want extra emphasis or contrast.

Senza means without.

It is followed directly by a noun or noun phrase:

• senza acqua = without water
• senza molto tempo = without much time
• senza aiuto = without help

In this sentence, senza molta acqua means without much water.

Because molto must agree with the noun it modifies.

Acqua is feminine singular, so the correct form is molta.

Compare:

• molto tempo = much time (masculine singular)
• molta acqua = much water (feminine singular)
• molti libri = many books (masculine plural)
• molte piante = many plants (feminine plural)

In Italian, when using molto/molta/molti/molte to mean much/many, you often do not need an article.

So:

• senza molta acqua = without much water

This is a very natural structure. Adding an article here would usually sound wrong.

Because acqua is an uncountable noun, like water in English. Italian normally keeps it singular when talking about an amount of it.

So:

• molta acqua = much water
• not a plural idea like waters

Italian is focusing on the quantity of a substance, not on countable items.

The normal and most neutral order is:

Queste piante sopravvivono senza molta acqua.

That is:

• subject: Queste piante
• verb: sopravvivono
• phrase with senza: senza molta acqua

Italian word order is somewhat flexible, but this version is the most straightforward. Changing the order is possible in some contexts, but it may sound more marked or literary.

Yes. Sopravvivere can be used in more than one way.

In this sentence it is used absolutely, without an indirect object:

• Le piante sopravvivono = The plants survive

But it can also be followed by a when it means to survive something/someone:

• sopravvivere a una malattia = to survive an illness
• sopravvivere a un incidente = to survive an accident

Here, senza molta acqua is not the object of the verb. It is just extra information: they survive without much water.

It is pronounced roughly like so-pra-VEE-vo-no, with the stress on vi.

Breaking it down:

• so
• pra
• vvi
• vo
• no

The double vv is pronounced more strongly than a single v. Also, the ending -ono is common in many they verb forms in Italian.

Yes, but it means something slightly different.

• sopravvivono = survive
• vivono = live

Sopravvivono suggests they are able to continue existing even in limited conditions. It highlights resistance or toughness.
Vivono is more neutral: they live.

So sopravvivono senza molta acqua gives the stronger idea that these plants can manage even with little water.

A simple breakdown is:

• Queste = demonstrative adjective, these
• piante = noun, plants
• sopravvivono = verb, they survive
• senza = preposition, without
• molta = adjective/determiner meaning much, agreeing with acqua
• acqua = noun, water

So the structure is:

[These plants] [survive] [without much water].