Sentences with phrase «when aphids»

When aphids attack a lettuce, they are notoriously difficult to control because they usually congregate in the tight central heart of the plant.

When aphids produce it, other aphids in the vicinity rapidly disperse.

Not exact matches

That's when phylloxera, the world's most famous aphid, laid waste to vineyards in the Cognac region, causing shortages and hyperinflation.

Their investigation began when Boe showed Johnson a photo of a cup plant flower teaming with insects, including a large colony of bright red aphids.

«When the larvae become adults, they chew a hole and pop out of the aphids,» Johnson said.

But so did the ladybirds (Coccinella septempunctata), even when there were no aphids for them to eat (Animal Behaviour, DOI: 10.1016 / j.anbehav.2012.01.008).

One such insect, the sap - sucking aphid (a common pest in gardens), has an effective escape plan, though: the bugs detect an approaching herbivore's breath and simply drop off the plant before it's eaten.Researchers at the University of Haifa at Oranim, Israel first noticed this phenomenon when they allowed a goat to feed on aphid - infested alfalfa plants — 65 percent of the plant pests simultaneously dropped to the ground just before the vegetation was devoured.The team suspected that several cues might have motivated the mass dropping, including the sudden shadow cast by the goat, plant - shaking triggered by the munching marauder and / or the herbivore's exhalations.

Ester and his colleagues found that when they sprayed the lettuces with a carbamate or organic phosphate insecticide, in combination with (E)- beta - farnesene, the aphids emerged from the lettuces and just one - tenth of the recommended dose of the pesticide was enough to kill them.

The body colour of Robichon's lab aphids is affected by environmental conditions, with the cold favouring green aphids, optimal conditions resulting in orange ones and white ones appearing when the population is large and faced with limited resources.

When jet ants go foraging they use marked trails to transport the honeydew they collect from aphids in special stomachs called «crops».

Carmen Blubaugh at Clemson University in South Carolina found that when caterpillars also snack on plants infested by aphids, the number of parasitoid wasps that attack the aphids decreases (Ecology, doi.org/ck8v).

When set on by aphids, the plant produces chemicals to attract wasps that parasitise the aphid — but if caterpillars join in, the plant doesn't have the resources to summon wasps.

Symbiotic relationships occur on a spectrum from parasitism (one species benefits at the expense of the other, such as a tick that sucks its host's blood) to mutualism (both organisms benefit, like when certain ants farm aphids for their honeydew while in return protecting them from predators).

I remember being in our garden in the US when I was about 6 or 7, and my mother receiving a package of live ladybugs in the mail, to release in the hope of battling the aphids.

When he points out a bug — an aphid, of which he has prodigious knowledge — on his pillow, she can't see a thing and then maybe, wait, yes, maybe... she can.

French Marigolds: When grown near other garden crops, French marigolds are claimed to stimulates their growth, while also repelling beetles, nematodes, aphids, potato bugs, and squash bugs.