Aphids Infestation in Gilgit City
Aphids (تیلی ) are small, soft-bodied insects pest common known as blackfly and greenfly. They come in a variety of colors, from green, red and yellow to black, brown, and gray. They are belonging to phylum: Anthropoda, class: Insecta, order: Hemiptera, and family: Aphididae. The morphology of aphids can be recognized by their pear-like shape, a pair of cornicles at the posterior end of the abdomen and fairly long antennae, whilst the winged form of aphids can generally be recognized by the venation and relative size of the front and hind wings. The life cycle of aphids is complex and plant species specific. The wingless females (stem mothers) reproduced via parthenogenesis during the summer. These stem mothers are unique to produce viviparity (living young) as opposed to eggs, as occurs or common in most other insects.
Ultimately, the plants inhabit the stem mothers and their offspring becomes congested or overcrowded then the offspring develop into adults with two pairs of large membranous wings and fly to other plants for food and/or atmosphere. Aphids are among the most detrimental insect pests for crops and herbaceous plants in temperate regions. They are feeding on phloem cells as colony, the food conduits of plants by inserting their slender mouthparts. They deteriorate the plants by sucking sap as well as act as vectors for plant viruses, and they distort plants by depositing honeydew and the subsequently growth of sooty moulds. While when the winged-adults fly to atmosphere then they causes serious irritation among the bikers and/or people in open places by entering into their eyes, nose, and mouth.
Globally, around 4400 species of aphids have been recorded, whereas in Pakistan approximately 92 native aphid species and 300 invasive aphid species are found. Common aphid species of Pakistan are included Rhopalosiphum maidis Fitch, R. padi L., Schizaphis graminum Rondoni, Sitobion avenae Fabricius, Sipha maydis Passerini, Macrosiphum avenae Fabricius, Aphis nerii Boyer de Fonscolombe, Myzus persicae Sulzer, Brevicoryne brassicae L., Macrosiphum, granarium Kirby, and R. rufiabdominalis Sasaki and Aphis Epilobii etc. Some common aphid species of Gilgit-Baltistan are included M. persicae, Eriosoma lanigeerum, Drosicha sp, Prunus armeniaca L. and Macrosiphum Euphorbiae, Thomas etc. The specie of aphids which is recently outbreak in Gilgit city is closely related to Aphis Epilobii, which is invasive and mostly found in temperate regions of the world. But further studies are needed to record major species of aphids of Gilgit-Baltistan because the introduction of new germplasm of plants and crops is common practice in the region without scientific studies.
The recent infestation of aphids in Gilgit city is causing serious irritation among the locals by entering into their nose, eyes and mouth. Mostly these black adult-winged aphids were recorded in and around broad leaf trees, viz., Chenar, Willow, and Populus during day time. They become nuisance and a source of fascination for people of Gilgit city. Some entomologists believes aphids fly at all times of the growing season but their massive outbreak is rare and associated to the climate change, mismanage agricultural practices and invasive plants species in certain regions. Aphids are poikilotherm in nature because their body is varies in temperature, and this is their strategy to survive with changes in environment to maintain their survivability and fertility. Some scientists found the mild winter temperatures, favorable growth temperatures (10-28 °C), high humidity, air pollution, (high level of carbon dioxides and ozone gases in atmosphere), rainy spring, absence of song-birds, parasitoids and ladybird beetles, wind or a favourable food source are major catalysts for aphid’s outbreak in certain areas. Some studies found that the increased temperatures, high levels of CO2 in atmosphere and changing precipitation patterns have significant impacts on agricultural production and aphids life cycle. The higher level of CO2 and O3 may alter natural photosynthesis rate of plants and ultimately favour aphids reproduction and fertility. Changes in climate may affect aphids in several ways, viz., spread out into new geographical regions, enhance their survivability throughout overwintering, augment their number of generations, distort their synchrony with plants, alter their interspecific relations with host plants, instigate risk of invasion of migratory aphids, increase incidences of insect-transmitted plants viruses and diseases, reduce effectiveness of biological control by their natural enemies. Consequently, posing a serious threat to crops economical losses and challenge to human food security.
Globally, several strategies and techniques have been used to manage with aphids outbreak including chemical sprays of neonicotinoids, carbamates, pyrethroids, cyclodienes, and organophosphates, and other traditional sprays of soap, neem oil, lemongrass oil, marathon, malathion, etc. But environmentalists believe biological and mechanical methods are more sustainable approaches to handle with aphids. For instance, the ladybird beetles, songbirds, and parasitiods are natural enemies of aphids because they are feeding on their larvae. Ladybird beetles love to inhabit on asteraceae or composite family plants (sunflowers, clovers, coreopsis, and calendula) for their development and growth. We need to propagate few of native composite family plants in our gardens to cope with aphids attacks. Protection and restoration of song-birds habitats and trees must be ensured to get by with enemy insects particularly aphids. Soda and kitchen soap mix liquid spray could be a home base approach to protect our gardens and vegetables from aphids attacks. Like other insects aphids also stay away from dry biomass smoke particularly straw smoke, which could be a good option at local level to deal with aphids. Otherwise we need to wait for higher temperatures of summer for their departure or minimum population in Gilgit city.
