Management of rice production systems to increase productivity

2.1. Introduction
CHAPTER TWO:
LOW‐INPUT UPLAND RICE PRODUCTION SYSTEM
In The Gambia, the upland rice ecosystem is defined as having free‐
draining soils where the water table is permanently below the roots of the
plant so that the crop depends entirely on rainfall. This is in agreement with
the IRRI’s Standard Evaluation System for rice which defines upland as level
to steeply sloping fields; rarely flooded, aerobic soil; rice direct seeded on
plowed dry soil or dibbled in wet non‐puddled soil (IRRI, 1996).
In The Gambia upland rice growing environment, drought and a short
growing season together with low soil fertility and rice blast disease are the
major constraints to productivity. Upland rainfed systems are associated with
higher production risk factors due to the unpredictable nature of rainfall. In
2000 rainfall was 7% above normal, in the following two years it was much
below normal (Table 2). This is an example of the unpredictable nature of
rainfall that farmers have to endure in The Gambia. This has a great impact
on the farmers’ cropping system and production risk factors.
Table 2. Rainfall Data at the Low‐Input Trial Site, Brikama, The Gambia
Year June July August September October Total
2000
2001
2002
60.1
111.9
37.9
275.3
250.8
66.1
247.5
208.4
204.7
253.6
241.1
226.3
134.2
55.1
56.3
970.7
867.3
591.3
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