Final answer:
The chief crops of Mississippi prior to the 1850's were corn and cotton, with cotton being the most economically significant crop and the foundation of the Southern economy.
Step-by-step explanation:
Prior to the 1850's, the chief crops of Mississippi were corn and cotton. Cotton emerged as the most important commercial crop, surpassing other agricultural products such as tobacco and rice in economic significance. By 1860, the South was producing two-thirds of the world's cotton supply, greatly driven by the invention of the cotton gin by Eli Whitney in 1793.
While rice was also a significant crop, particularly in areas like the Carolina low country where the environment was well-suited for its growth, cotton became the foundation of the Southern economy. The vast production of cotton was closely tied to the use of enslaved labor, leading to a deep intertwining of cotton and slavery in the region's cultural and economic identity, especially by the 1850s.