Notes to broadcasters
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Weeds are defined as plants growing in places where they are not wanted by people. Annual weeds live less than one year and die after producing seeds. Perennial weeds live after they have produced seeds, sometimes for many years. Some species of perennial weeds have special kinds of roots such as tubers or rhizomes that survive and propagate after tillering. These roots break and remain in the soil when you pull on the plant, making hand-weeding difficult.
Wild rice, which looks a lot like rice, is one of the most problematic perennial weed species in irrigated and lowland rice. Herbicides are not recommended on wild rice as they can damage the rice crop.
Weed management can be a challenge but farmers who discover successful strategies will be rewarded with higher crop yields. This program discusses the benefits of several management strategies, including plowing, flooding, transplanting from a nursery bed, and crop rotation.
Rice farmer (Mr. Fofana)
Farmer training officer (Mr. Diallo)
Signature tune to introduce program
: Dear listeners, good morning and welcome to your favourite program about agriculture. The theme of today’s show is weed management, and to discuss this I’m joined by two guests in the studio, Mr. Fofana, who is a rice producer, and Mr. Diallo, a training officer working with a local farmers’ organization.They are going to talk about their own experiences with weed management. Welcome to you both.
FARMER AND TRAINING OFFICER:
: Mr. Diallo, let’s start with you. Tell us how the farmers that you are working with deal with weeds in their rice fields.
Well, of course it depends on the weed.There is a specific weed that looks like rice, that we call wild rice. This weed is particularly difficult to control because when it is uprooted the rhizomes break fairly easily. Broken parts of these roots can survive and grow quickly.When farmers have wild rice in their plot, they need to plow it and then collect the roots that are exposed to the sun. Some women put the roots in baskets and throw them away…others pile them up. After two weeks under the sun, they burn the heaps. I think Mr. Fofana has experience with that weed.
Yes, I have exactly that troublesome weed in my field.
Have you been able to get rid of it?
Yes. First I plowed my field to uncover the roots. But that isn’t enough. I then hit the clods with a small hoe, removed the roots and piled them in a heap. After two weeks of sun-drying, I burnt the heaps and used them as organic manure. But for a few years I had to pay particular attention, as it is very difficult to remove all roots at once.
And there’s another reason that plowing is useful. When you plow, many kinds of weed seeds get buried deep in the soil, so far down that they can’t germinate.
So from what you’re saying, it seems that plowing is an important step in controlling weeds…wild rice and other weeds too.
Yes, but plowing is only the first step. After the plowing is done, leveling and flooding are the next steps. Flooding the field for two weeks kills most of the weeds. But flooding only works if you level the field properly. If parts of the field are not flooded because you haven’t leveled it, the weeds will grow and spread.
And what do you say to farmers about the right time to flood their fields?
I suggest that you flood your field after the first field preparation.>Keep it flooded for a few days, and then drain the field. Then, when you see the first sign of weed growth, you can weed and flood the field for a second time. This keeps the weeds down before planting starts.
And then, once the crop is growing, the plot needs to be weeded again. Am I right?
Yes, and the timing of weeding is very important. Weeds are more harmful in the first six weeks of the rice crop. If you use direct seeding, do the first weeding after three weeks, when the rice plant has four leaves. Two or three weeks later, at tillering, you must weed a second time.
I’ll repeat that for the benefit of our listeners. Do the first weeding when the rice plant has four leaves. Two or three weeks later, at tillering, it’s best to weed again.
That’s correct if you use direct seeding. But if the rice has been transplanted from a nursery, you need to weed only one time, at the beginning of tillering. When you apply fertilizer, there shouldn’t be any weeds in the field. You don’t want to fertilize the weeds!
Mr. Fofana, I know that you’ve been growing rice for many years. If you compare direct seeding and transplanting, which would you say is more effective in controlling weeds?
I have tried both methods and learned that transplanting is better.What I mean is that if I transplant two-week old seedlings from a nursery into the field, that gives the rice a good advantage over weeds.But sometimes farmers can’t use the transplanting method. So they use direct seeding. If you must do direct seeding, make sure that you germinate your seeds before sowing them. That will help.
Also, when you transplant seedlings, the spacing is important. If there is too much space between rice plants,weeds can grow more easily. Leave about twenty centimetres between the rice plants so you can move around the plot without damaging the plants. If the spaces are too narrow, you trample on the rice plants when you weed.
I find it’s also easier for me to do hand weeding if I plant rice in rows. Some weeds look a lot like rice, so if I see a plant outside the row, I can be sure that it’s a weed. In our neighbouring district, I have seen farmers using a rotary weeder. It is a handy mechanical tool with which they easily weed in between rows. Next time I visit that area, I will surely buy one as it makes weeding much easier and I won’t have to hire more labour.
Is there anything else you’d like to offer before we sign off?
Apart from these things, I also do a rotation of crops. If the land can bear three crops per year, that’s a way to reduce weeds. Weeds can’t survive in a field if you keep changing the crop. For example, I use the rotation of corn, rice, and potatoes. Taking up this cycle for two or three years or more, I manage to control most weeds…even wild rice.
Fade in, then fade out background music
Thank you, Mr. Fofana and Mr. Diallo. You’ve provided valuable information for those of us who are trying to keep weeds down. We’ve talked about the benefits of several approaches… plowing, flooding, transplanting and crop rotation. On the weeded farm, the nutrients in the soil and the fertilizer that you apply benefit only the rice. The rice plant, with fewer competitors, develops well and yields better.
Thank you for listening. If you wish to have a copy of the video CD on weed management or other rice technologies, please contact me at this station[the radiobroadcaster should give a mobile number or the number of the radio station. Please see notes below for information about obtaining rice videos from the Africa Rice Center].
Fade in signature tune. After 30 seconds, fade outbackground music and hold under host.
Contributed by: Felix S. Houinsou, Rural Radio Consultant/WARDA, and Radio Immaculée Conception, Benin, a Farm Radio International broadcasting partner.
Reviewed by: Paul Van Mele, Program Leader, Learning and Innovation Systems/Africa Rice Center (WARDA)
Information provided by: Jonne Rodenburg, Weed Scientist/Africa Rice Center (WARDA)
The International Fund for Agricultural Development (IFAD) for supporting participatory research with women rice farmers in lowlands. The Bill & Melinda Gates Foundation, USAID and IFAD for supporting this script and for translating the rice videos into local languages.
If you are interested in receiving videos about different rice technologies, please contact Jonas Wanvoeke at the Africa Rice Center (firstname.lastname@example.org; +229 21 35 01 88; 01 BP 2031, Cotonou, Benin). For a list of rice videos available, please see: www.warda.org/warda/guide-video.asp