corn ((floor)), wheat

“Corn” From Boyd’s Bible Dictionary:

(kernel). In a Bible sense, grain of all kinds except our maize, or Indian corn. Used largely in figurative speech (Gen. 41:2222And I saw in my dream, and, behold, seven ears came up in one stalk, full and good: (Genesis 41:22); Ex. 9:3232But the wheat and the rie were not smitten: for they were not grown up. (Exodus 9:32); Deut. 11:14; 18:4; 28:5114That I will give you the rain of your land in his due season, the first rain and the latter rain, that thou mayest gather in thy corn, and thy wine, and thine oil. (Deuteronomy 11:14)
4The firstfruit also of thy corn, of thy wine, and of thine oil, and the first of the fleece of thy sheep, shalt thou give him. (Deuteronomy 18:4)
51And he shall eat the fruit of thy cattle, and the fruit of thy land, until thou be destroyed: which also shall not leave thee either corn, wine, or oil, or the increase of thy kine, or flocks of thy sheep, until he have destroyed thee. (Deuteronomy 28:51); 2 Chron. 2:1515Now therefore the wheat, and the barley, the oil, and the wine, which my lord hath spoken of, let him send unto his servants: (2 Chronicles 2:15); Isa. 28:2525When he hath made plain the face thereof, doth he not cast abroad the fitches, and scatter the cummin, and cast in the principal wheat and the appointed barley and the rie in their place? (Isaiah 28:25); Ezek. 27:1717Judah, and the land of Israel, they were thy merchants: they traded in thy market wheat of Minnith, and Pannag, and honey, and oil, and balm. (Ezekiel 27:17); Matt. 12:11At that time Jesus went on the sabbath day through the corn; and his disciples were an hungred, and began to pluck the ears of corn, and to eat. (Matthew 12:1)).

“Wheat” From Boyd’s Bible Dictionary:

This well-known cereal was cultivated in the East from the earliest times

“Corn” From Concise Bible Dictionary:

 
Various Hebrew words are translated “corn,” and usually signify any kind of grain. The “OLD CORN OF THE LAND” was what the Israelites began to eat after crossing the Jordan, when the manna ceased (Josh. 5:11-1211And they did eat of the old corn of the land on the morrow after the passover, unleavened cakes, and parched corn in the selfsame day. 12And the manna ceased on the morrow after they had eaten of the old corn of the land; neither had the children of Israel manna any more; but they did eat of the fruit of the land of Canaan that year. (Joshua 5:11‑12)). It typifies a heavenly Christ, on whom those feed who have spiritually passed through Jordan—who are experimentally dead and risen with Christ. The manna is rather heavenly grace for wilderness circumstances. In the New Testament Christ speaks of Himself as a “CORN OF WHEAT,” which had to die or it would abide alone: there could be no association in life with Christ except through death and resurrection (John 12:2424Verily, verily, I say unto you, Except a corn of wheat fall into the ground and die, it abideth alone: but if it die, it bringeth forth much fruit. (John 12:24)).
 
Wheat growing in Israel.

“Wheat” From Concise Bible Dictionary:

 
Wheat Growing in Israel
This cereal was extensively grown in Palestine; the harvest was in May and June. In the parable it is used by the Lord as representing the children of the kingdom, the fruit of the good seed that He was sowing on the earth, in contrast to the tares, or darnel, which Satan secretly sowed among the good seed.
The Lord Himself, being the second Man “out of heaven,” is compared to the grain of wheat that must have remained alone unless it had died, but which in dying would bring forth much fruit. This clearly shows that there was no union of Christ and natural man by His incarnation alone, and that through the death of Christ the fruit produced by His resurrection is of the same order as Christ Himself (Matt. 13:25-3025But while men slept, his enemy came and sowed tares among the wheat, and went his way. 26But when the blade was sprung up, and brought forth fruit, then appeared the tares also. 27So the servants of the householder came and said unto him, Sir, didst not thou sow good seed in thy field? from whence then hath it tares? 28He said unto them, An enemy hath done this. The servants said unto him, Wilt thou then that we go and gather them up? 29But he said, Nay; lest while ye gather up the tares, ye root up also the wheat with them. 30Let both grow together until the harvest: and in the time of harvest I will say to the reapers, Gather ye together first the tares, and bind them in bundles to burn them: but gather the wheat into my barn. (Matthew 13:25‑30); John 12:2424Verily, verily, I say unto you, Except a corn of wheat fall into the ground and die, it abideth alone: but if it die, it bringeth forth much fruit. (John 12:24); 1 Cor. 15:48-4948As is the earthy, such are they also that are earthy: and as is the heavenly, such are they also that are heavenly. 49And as we have borne the image of the earthy, we shall also bear the image of the heavenly. (1 Corinthians 15:48‑49)).
There are three or four varieties of Triticum grown in Palestine.

Strong’s Dictionary of Hebrew Words:

Number:
1715 (find all occurrences in KJV Bible)
Transliteration:
dagan
Phonic:
daw-gawn’
Meaning:
from 1711; properly, increase, i.e. grain
KJV Usage:
corn ((floor)), wheat