The study looked at how different amounts of water and fertilizer affect cotton growth and yield. They tested three levels of drip irrigation and five levels of fertilizer on cotton plants. The results showed that when plants received enough water and fertilizer, they produced more cotton. The best combination was full irrigation with a medium amount of fertilizer. Using too little or too much water and fertilizer decreased cotton yield. Overall, giving the plants the right amount of water and fertilizer led to the highest cotton production in arid regions of northwest China.