| Species: | Petrobia latens | |
| Genera: | Petrobia | |
| Family: | Tetranychidae | |
| Distribution: | South Africa, Yemen, Zimbabwe, Australia, New Zealand, Mexico, USA, Argentina, Chile, India, Pakistan, Algeria, Armenia, China, Denmark, Egypt, France, Germany, Hungary, Iran, Ireland, Italy, Japan, Kazakhstan, Korea, Netherlands, Poland, Spain, Turkey, United Kingdom | |
| Host Crops: | More than 100 crops are reported belonging to families Alliaceae, Asclepiadaceae, Asparagaceae, Asteraceae, Boraginaceae, Chenopodiaceae, Commelinaceae, Convolvulaceae, Cucurbitaceae, Cupressaceae, Fabaceae, Fumariaceae, Geraniaceae, Hippocastanaceae, Iridaceae, Lamiaceae (Labiatae), Liliaceae, Malvaceae, Moraceae, Nyctaginaceae, Onagraceae, Oxalidaceae, Papaveraceae, Plumbaginaceae, Poaceae, Polygonaceae, Polypodiaceae, Rosaceae, Rutaceae, Ulmaceae, Violaceae, Vitaceae, Zygophyllaceae Important crops are wheat, barley, citrus and lentil. | |
| Nature of Damage: | Leaves dry up from tip to downwards; start showing yellowing appearance which ultimately dries out. Heavily infested plant gives sickly appearance. | |
| Life Cycle: | There are five developmental stages from egg to adult. Each stage except egg is followed by a quiscent stage. The mite moulted at the termination of each quiescent period. The average pre-oviposition period is 1.8 days while one generation is completed in about 20 days. A female lays either non-diapausing winter eggs (8-13 /day) or diapausing summer eggs (2-5/ day) at one time with a total of 29-110 winter or 11-43 summer eggs per female. The winter eggs are deposited mainly on dry leaves, which are brick red in colour. Eggs are laid singly or in batches. While the summer eggs are white and laid on soil clumps in clusters. These diapausing eggs remain dormant throughout summer and rainy season. The eggs hatch in 8-13 days. The larva has 3 pair of legs and larval period is 1-2 days followed by a quiescent stage. The protonymphal and deutonymphal period is 0-3 and 1-4 days, respectively, and possesses four pair of legs. The longevity of adult female is 20 days. | |