Beans/Cowpea Business: Storage Tips
The most important insect pests of stored cowpeas are called bruchids. These insects infest the crop in the field, and the infestation can get worse in storage.
Because damage in storage can be so serious, farmers often sell their crops immediately after harvest. But selling cowpeas right after harvest is a problem. The selling price is much lower just after harvest than it is a few months later. So, if a farmer can store the seeds safely for a few months and then sell them, he or she will receive a much better price. Also, unless a farmer uses good storage practices, the cowpea grain gets insect holes, and buyers won’t pay as much because of this damage.
That’s why we want to talk about controlling bruchids. There are several ways to store cowpea to discourage bruchid damage. You can mix the grain with equal parts of ash, you can use a solar heater made of plastic or corrugated tin to kill the insects, or you can treat the crop with various oils and plants. But the method which we will talk about today is storing the grain in two different types of airtight containers: metal drums and plastic bags.
You see, bruchids can’t live without air. This is why airtight containers are so effective. First, let’s talk about metal drums. (Short pause) In some places, old oil drums are easily available and relatively cheap. The tops of these drums have screw-type plastic lids, which makes them airtight and effective at discouraging bruchids.
Start by filling the drums to the top with dry threshed cowpea grain. Each drum holds about 45 to 55 kilos of grain. After filling the container, seal it, and then use peanut or another cooking oil to lubricate the edge of the closure. This ensures an airtight seal.
The oil also makes it easier to remove the lid after months of storage. Filled drums can be stored for six months with very little loss to cowpea bruchids.
Because the drum doesn’t permit air from the outside, the bruchids will eventually die. That is why using metal drums is an effective method.
The second method that we want to tell you about today is triple bagging. This method requires three clear plastic bags which hold fifty kilograms of cowpeas. Thus the name: ‘triple bagging’. The plastic bags are placed one inside the other to keep out insects.
You have to be careful that the plastic bags have no holes, because even extremely small holes will reduce the effectiveness of this method. And remember that one or two bags is not enough to ensure success. You need three!
Here’s how this method works: Fold back the top of first bag and put the second bag inside of it. Then fold the second bag over the outside of the first. Next, put the third bag inside of the first two and fold it over the first two.
Slowly and gradually fill the inner bag with cowpeas, making sure to shift or gently rock the bags frequently to eliminate any air pockets inside. Fill the inner bag nearly to the top. Then firmly draw together the top of the innermost bag, squeezing tightly to press air out of the bag. Gently rock the bag of cowpeas back and forth again to eliminate any air spaces.
After the cowpeas are well settled in place, squeeze the innermost bag again to force out any air, and then tie the bag closed with string or cord. Twist up the remaining plastic above the tie and fold this plastic in two. Then tie the double-folded plastic together.
Repeat this tying procedure individually for each of the three bags. Then store the bags in a cool place. You can now be sure that your cowpeas are safe from pest attack.
Airtight storage in triple plastic bags is easy to use, effective, and safe. Try it and you will like it. But be careful not to handle the plastic bags roughly – it’s important that the bags not have any holes.
Remember to use three plastic bags, and as you pour in the cowpeas, rock gently to eliminate air spaces. Strongly tie all the plastic bags in order. And I believe you remember how to use a metal drum. Make sure that you use a good tight lid, and a drum that’s not too old and rusty.
Source: Farm Radio