Three of the 12 irrigation perimeters where SRI was tested suffer from flooding every year, when the water rises in the adjoining arms of the Niger River. In most years, this flooding happens late in the cropping season, during the rice plants’ flowering or grain filling stage. This year, these perimeters were flooded early, when the rice was in the tillering stage.
In order to get to the SRI plots, nine farmers from Donghoi village came to meet us in their dugout canoe early in the morning to take us to the rice fields. A cheerful crowd welcomed us aboard and offered us food and tea, making for an extremely pleasant 45-minute ride. Upon arrival, we walked through knee-deep water to the SRI plots.
October 23, 2008
Flooded Irrigation Perimeters
SRI Timbuktu Blog
The early flooding (six weeks after planting) was not beneficial for plant development under SRI. Roots constantly under water cannot be properly aerated, and the cono-weeder is not as effective as under controlled irrigation. According to farmers, flooding also makes plants grow taller and reduces tillering. Nevertheless, we observed a superior performance of the SRI plots compared to the control plots, even if the differences weren’t as clear as in the villages where irrigation is fully controlled.
Farmer Gouro Almadane (middle picture) of Donghoi village is facing another difficulty with his flooded SRI plot: he would like to fertilize his crop, but putting urea into the flooded field is ineffective. Much of the fertilizer would be lost, drifting away and evaporating, before the plant roots could take it up.
Africare field agent Ibrahima shows us the flooded SRI (left) and control plot (right) of farmer Backa Abdou of Niambourgou village.
Which one is the SRI plot?
Of all the 60 SRI plots, we saw the greatest impact from the combination of manuring the soil and using the cono-weeder in the two Donghoi village plots that were not flooded.
Farmer Hamadoun Baba applied the same amount of manure to both the SRI and control plots, and did not use any chemical fertilizer on either one. He weeded the SRI plot three times with the cono-weeder. The effect was immediately apparent: the SRI plants are much greener and developed much more vigorously than those in the control plot.
Farmer Hameye Kelly (right), who also used the cono-weeder three times on his SRI plot fertilized with manure, observed a similar effect. Unlike Baba, Kelly applied neither manure nor fertilizer to his control plot.
Two abandoned SRI plots
The two worst-performing SRI plots are in Niambourgou village. Farmers Hama Bouyeye and Kaga Bouyeye explained that the villagers who manage irrigation in the perimeter refused to provide water when needed for the SRI plots, although they had previously agreed to do so during the initial village organizational meeting with the Africare field agents.
As it was, the SRI plots were irrigated for the first time eight days after transplanting, but it was late: many of the rice seedlings had already died. The two farmers, discouraged, admitted to having abandoned their SRI plots. They did not replace the missing seedlings, never used the cono-weeder, and didn’t apply any fertilizer. On the other hand, they did weed and fertilize the control plot. Despite the very unequal treatment, the remaining SRI plants still show superior tillering compared to those in the control plot.
“ Better hurry to catch the next pirogue taxi”
The only other similar case happened in farmer Maya Hama's plot in Findoukaina village. She neglected to water the plants in the nursery before transplanting, and then waited a few days to irrigate her newly-planted SRI plot, losing about three-quarters of her SRI plants. Unlike the two farmers from Niambourgou village, she replaced the seedlings that didn't survive. All the other 57 SRI plots were irrigated immediately after planting and did not experience any remarkable plant mortality. Lesson learned: it is vital to irrigate after planting.
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