Updated: Jul 6, 2019
The melons have a special place in our yearly cropping routine as they were our first irrigated crop. This year we got our best harvest ever of muskmelons but were stunned when few of our customers discovered worms in the melons! Even more puzzling fact was that worms were in fruits with no visible damage. We were told these were fruit fly larva by the experts.
The big question we had was, how did fruit fly larva get into the fruit? According to experts fruit flies lay eggs in the flower. Since we did not use insecticides they survived into fruit stage to become a larva. The larva is most expressive in ripe fruit otherwise would have been premature, un noticeable and harmless when consumed. We learnt that using bug traps is the safest way to prevent larva in the fruit.
The bug traps help in capturing the egg-laying adults thereby stopping their lifecycle. Convinced with this hypothesis we went to shop for bug traps. In the market we found bug traps that used color, light and pheromones to attract & trap the bugs. They also came at various price range and promises, confusing us even further.
As we were exploring bug traps Srikanta Prakasha, an old friend of ours who had lived through all of this wrote to us about the fly trap that he had built with instructions from Youtube. According to him the fly trap works very well and captures approximately 300 flies a week. It is simple to implement: Take 2 ltr soda bottle, remove the cap, cut the funnel portion and invert into the bottle. Cover the cut portion with tape. Add soap solution + little water + meat pieces. Suspend this bottle from a tree. Flies find it irresistible and fly into the bottle then get trapped.
Taking in all of this useful information we decided to go with the sticky bug traps at our farm. Our thought is that sticky bug trap will help us to record the type & count of bugs. We are hoping that this data will help us to build safe and cost effective pest management in future.
While humans are devising bug traps, nature is abundant with ingenious traps. Here is an interesting bug trap that I found by chance. Notice the tiny holes in the ground.
It can be passed off as a marking left by a sharp object on the ground. This conical depression in the ground is the trap built by predatory larva of an insect called Antlions. During the metamorphosis Antlion larva create these slippery sloped conical depressions. Once the pray slips to the bottom it is caught by Antlion which sits buried in the dirt at bottom of the trap. In the video that follows notice how an ant thrown inside will find it hard to climb out and as soon as the ant slips to the bottom the Antlion larva grabs the ant with its claws.
This trap reminded me of the Hollywood movie Tremors. I did a bit of research and learnt that post the pupa Antlion turns into a harmless flying wonder similar to the dragonfly. Next video shows Antlion larva that laid this master trap.