Abstract:
As one of important food crop, rice (Oryza sativa L.) is cultivated across Rwanda, it plays a critical
role in nation food security. The use of fertilizers is sensitized for increasing production, however there
is a need of proper use of nitrogenous fertilizer as the most important nutrient which may limit the
production or causes the pollution when are not used efficiently by plant. Therefore, this study
investigated rice response using growth and yield parameters, correlation among parameters and
nitrogen use efficiency (NUE), in four different treatments selected; T0 (Control), T1 (FFP; nitrogen
was splited three times), T2 (Basal; all nitrogen applied as basal), T3 (SSNM; site specific nitrogen
management) these treatments were replicated three times in randomized complete block design
(RCBD) in Cyili wetland south province of Rwanda, analysis were performed using genstat statistical
software.
The result showed no significant difference at p<0.05 observed in all treatment on plant height,
number of tillers, panicle weight ,1000 grain weight and grain yield. Significant difference at p<0,05
was observed on dry matter and nitrogen uptake.
Adherence between parameters using (Pearson’s correlation coefficient) were observed on following
basis: Panicle initiation showed strong positive correlation with number of tillers (0.9983), negative
correlation with plant height (-0.8716), strong positive correlation with grain yield (0.9182) and
moderate positive correlation with 1000 grain weight (0.4486). Number of tillers have negative
correlation with plant height (-0.8881), strong positive relationship with grain yield (0.9394) and
moderate positive relationship with 1000 grain (0.4987). Plant height show negative relationship for all
parameters; grain yield ,1000 grain weight, panicle weight, number of tillers; (-0,8904), (-0.7336),
(-0.8881), (-08716) respectively. Grain yield have positive correlation with 100 grain yield weight of
(0.7336).
Result of three different indicators of NUE revealed SSNM to be the best method which use N
efficiently with Partial factor productivity of 100kg kg
-1
, Agronomic efficiency of 21kgkg
-1
and
Recovery efficiency of 78%. And enhanced yield and profit by saving form of reduced fertilizer use,
without a reduction in yield, it reduces as well N
2
O emission, by decreasing the total N application and
timing to crop need.
