Nitrogen effects on leaf gas exchange, vegetative growth and yield of black pepper plants using Gliricidia sepium as living support

For the implantation of one hectare black pepper (Piper nigrum), about 25 to 30 trees are removed from Amazon Forest produce tutors for pepper. As an alternative dead wooden stake (WS), there is sustainable cultivation with tree species, living supports (LS) gliricídia (Gliricidia sepium L.). However, inadequate technical information on effect species growth, physiology, and production culture. Therefore, objective this study evaluate vegetative pepper, cultivated in a LS subjected doses nitrogen (N). The experiment was carried randomized design blocks, split plots, three replications field. plots consisted two (dead tutor live G. sepium) subplots increasing N (10, 20, 40 60g plant-1). results indicated that plants WS stand out terms initial growth; however, at end first year tends present growth slightly like WS. green higher sepium, while dry no distinction between tutors, only affected, which estimated 37 g plant-1 obtain highest productivity Key words: Black Grain yield, Vegetative Nitrogen competition, growth.