In Genesis 1:28, God says to Adam and Eve, "Be fruitful..." Does the term fruitful specifically refer to child-bearing, or is it used in general way to refer to the successes they were intended to have through, agriculture, raising children and ruling over the whole earth?
In the immediate context of Genesis 1:26-28 the subject is first the creation of man followed by the commands given to Adam in verse 28. That would make the context of 1:28 dealing primarily with the procreation of mankind.
The Hebrew word פְּר֥וּ (which is normally rendered as fruitful), is typically understood of as either the fruit of the vine or the fruit of the womb, with the context setting the range. In this case, the procreation of mankind that is the subject in the passage. The additional phrases you left off also point to procreation -- it was to be fruitful and multiply and fill the earth.
Gen 1:28 NKJV Be fruitful and multiply; fill the earth and subdue it; have dominion over the fish of the sea, over the birds of the air, and over every living thing that moves on the earth.
While many might look at Genesis as metaphorical, I hold that it is literal and therefore Adam is told to multiply and fill the earth with his children.
Genesis 5 is meant to show how this command was fulfilled. Genesis 5:1-2 corresponds with Genesis 1:26-27
Gen 1:26-27 NKJV 26 Then God said, “Let Us make man in Our image, according to Our likeness; let them have dominion over the fish of the sea, over the birds of the air, and over the cattle, over all the earth and over every creeping thing that creeps on the earth.” 27 So God created man in His own image; in the image of God He created him; male and female He created them.
Gen 5:1-2 NKJV This is the book of the genealogy of Adam. In the day that God created man, He made him in the likeness of God. 2 He created them male and female, and blessed them and called them Mankind in the day they were created.
Then Genesis 1:28 corresponds with Genesis 5:3-32
Genesis 1:28 28 Then God blessed them, and God said to them, “Be fruitful and multiply; fill the earth and subdue it; have dominion over the fish of the sea, over the birds of the air, and over every living thing that moves on the earth.”
Genesis 5:3-32 3 And Adam lived one hundred and thirty years, and begot a son in his own likeness, after his image, and named him Seth. 4 After he begot Seth, the days of Adam were eight hundred years; hand he had sons and daughters. 5 So all the days that Adam lived were nine hundred and thirty years; and he died. 6 Seth lived one hundred and five years, and begot Enosh. 7 After he begot Enosh, Seth lived eight hundred and seven years, and had sons and daughters. 8 So all the days of Seth were nine hundred and twelve years; and he died. ...
It is also important to understand that the same command was given to Noah and his sons following the flood in Genesis 9:1
... Be fruitful and multiply, and fill the earth.
Adam would struggle to raise crops following the fall, and Noah would struggle to gather animals for food because the animals would be fearful of man.
As I interpret the text of Genesis, I do so literally. I presuppose Genesis to be a literal narrative involving real people and real events. Those who interpret Genesis figuratively and metaphorically have different presuppositions.
It's referring to childbearing. In most Bibles, Gen 1:28 and Gen 9:1 come very close to matching word for word. That's Adam and Eve starting mankind, then Noah's family having to restart mankind.
(KJV) “…God said unto them, Be fruitful, and multiply…” Gen 1:28 “God…said unto them, Be fruitful, and multiply…” Gen 9:1
(DRA) “…God blessed them, saying: Increase and multiply…” Gen 1:28
“And God…said to them: Increase and multiply…” Gen 9:1
(YLT) “And God blesseth...and God saith to them,
Be fruitful, and multiply’… Gen 1:28 “And God blesseth…and saith to them,Be fruitful, and multiply’…” Gen 9:1