Resposta do cafeeiro irrigado a diferentes tensões de água no solo sob dois sistemas de plantio.

Abstract

The objective of this work was to study, at two different planting densities and during the first three harvests, coffee yield response to irrigation performed at different soil tension levels. The experiment was carried out at the Universidade Federal de Lavras/MG. Coffee plant (cv.“Rubi” - MG- 1192) was planted in 01/03/01. Five irrigation treatments were evaluated:(i) not irrigated and irrigated when soil water tension, at 25 cm depth, reaches (ii) 20, (iii) 60kPa, (iv) 100(v) and 140kPa (vi). For the 20 and 60kPa treatments tension was controlled with tensiometers, in other treatments were controlled with Water Mark-Irrometer soil moisture sensors. Two planting densities were used: (i) 2500 (4.0x1.0m) and (ii) 10000 (2.0x0.5m)plants/ha. During the first three years, it was observed increased coffee yields (60kg bags/ha) with the increased irrigation depths required to keep the lower soil tension levels. For the 2500 and the 10000 plants/ha densities, the highest coffee yield were achieved with the 20kPa tension: 50 bags/ha, with a 170.0mm irrigation depth, and 102 bags/ha with 232.4mm, respectively. During this period, lower coffee yield fluctuations were observed with the 10000 plants/ha.