Coffee response to nitrogen and soil water content during the early growth stage

Coffee (Coffea arabica L.) is the major crop grown in highland and mountainous areas of Colombia, where the most common yield‐limiting factors are nitrogen (N) and soil water content. Since the eventual success of a plantation is determined by the performance of coffee plants during critical early stages, our goal was to better understand plant response to these limiting factors. Four different levels of N and soil water content were evaluated under greenhouse conditions for their effect on growth, water use efficiency, fertilizer‐N recovery efficiency (FNRE), and stem lignin and cellulose of coffee seedlings. The interaction between N and moisture did not produce a significant response in coffee growth. However, by increasing N, both water use efficiency and ¹³C content were enhanced, while growth, recovery of urea by plants, and stem strength were decreased. Water stress due to low soil water content increased water use efficiency, ¹³C content, and root to shoot ratio, but decreased shoot growth. These results demonstrate the effects of N supply and water balance and highlight the excessive amount of N typically applied to coffee seedlings as well as the importance of the acclimation process of young plants to changes in soil N and water. All of these are important considerations in improving management strategies to reduce environmental impact while sustaining optimal productivity.