NJOKA E.M., WANJOGU R.K, OGENDO J. O, NDIRANGU C. M., NJOROGE J. M.
Abstract
Field studies were conducted to evaluate the effects of different tillage (zero,
dry ploughing and rotavation) methods on the growth and grain yield of two irrigated
lowland rice varieties, NIB AM 108 AND NIB AM 10 at the Mwea and Ahero Irrigation
Schemes. The treatments were laid out in a randomised complete block design
with three replicates per site. Results indicate that the NIB AM 108 yields
under dry ploughing were significantly (P<0.05) lower than zero tillage and
rotavation at Ahero in the first season. At Mwea NIB AM 10 yielded significantly
(P<0.05) higher under dry ploughing in the second season but no significant
differences (P<0.05) in yields were recorded during the second season. The
same result trends were observed for tillering, 1000-kernel weight, height and
harvest index at both sites and seasons. There were no significant differences
in growth parameters for NIB AM 10 at Mwea due to different cultivation practices.
It is reasonable to conclude that zero tillage would be a possible alternative
method of land preparation for irrigated rice at Mwea and Ahero.
Key Words:
dry ploughing, rotavation, zero tillage, irrigated rice