Root distribution of arecanut (Areca catechu L.) as influenced by drip fertigation in a laterite soil

Abstract

As part of a long-term study on drip fertigation initiated in 1996, the root distribution of arecanut was examined in April-May 2005 in 50% NPK, 75% NPK and 100% NPK fertigation at 10 days interval, 100% NPK soil application with drip irrigation, basin and sprinkler irrigation methods. Horizontal spread of root system was more in drip fertigation (135-144 cm), while it was only 121 em in case of sprinkler and basin methods. Rooting depth was also more in drip fertigation (101-136 cm) than in basin and sprinkler method (77-78 cm). Drip fertigation resulted in production of higher fine root biomass (34-43%) than drip + 1000/0 NPK soil application (33%), basin (22%) and sprinkler irrigation (21%). Maximum distribution of roots both fine and thick was noticed with in 50 em radius from the base of the palm and decreased at 50-100 em distance and depth in all the treatments. The weight density of both fine and thick roots was more along dripping plane than along non-dripping plane at 0-50 em soil depth. With increase in distance from the base of the palm, the root weight density decreased. The extent of decrease was more with basin irrigation, followed by sprinkler irrigation compared to drip fertigation.