COMPARATIVE EVALUATION OF CONTROLLED RELEASE FERTILISERS FOR NITRATE LEACHING
Loading...
Date
DOI
Open Access Location
Journal Title
Journal ISSN
Volume Title
Publisher
Rights
The Author(s), Massey University
Abstract
A lysimetric study was carried out with an objective of evaluating the leaching behaviour of
different fertilisers on spinach growth on Manawatu sandy soil. The fertiliser treatments
applied were urea, two controlled release fertilisers called ‘g’and ‘SmartN’ at the rates of 50 kg
N/ha (50N), 100 kg N/ha (100N) and 200 kg N/ha (200N). The 200 kg N/ha urea application
was made in 10 split doses at a rate of 20 kg N/ha in 7-day intervals, whereas 200N application
of ‘g’ and ‘SmartN’ were made twice at a rate of 100 kg N/ha at the time of planting and six
weeks after planting. The control treatment did not receive any fertiliser application (0N). The
application of Urea and ‘g’ at all rates except ‘g’-50N produced significantly higher nitrate
leaching losses (19.8 to 27.7 kgN/ha) compared to the control (9.1 kgN/ha), while SmartN at
all rates produced no significant increase in nitrate leaching. The total nitrate leached per ton of
dry matter production was significantly reduced by the application of N fertilisers compared to
the control (135.1 kgNO3
-
-N/MgDM). On an average, 16.4 kg NO3
-
-N/MgDM was leached
from the fertilised treatments. Dry matter production increased at 200N application rates with
all three fertilisers, but urea-200N produced the highest dry matter yield of 2377 kg/ha. In
conclusion, frequent split applications of urea (urea - 200N) increased dry matter yield thereby
significantly reduced nitrate leaching.
Description
Keywords
Controlled release fertilisers, leaching, lysimeter, nitrate, SmartN.
Citation
pp. ? - ? (6)