Applied Microbiology: Open Access
Open Access

Abstract

First Report of Alternaria Blight of Potatoes in Nomal Valley, Gilgit-Baltistan Pakistan

Aqleem Abbas

Gilgit-Baltistan (GB) having unique geographic and climatic conditions was free from plant diseases. Since the disease resistant traditional varieties of plants have been replaced by high yielding varieties. As a result major threats come in the form of diseases such as Late blight and Early blight of potato and tomato crops, Grey mold of Grapes, Powdery mildew of cucumbers, Botrytis leaf virus in onions, Crown gall disease of cherries and nematodes of potatoes. The introduction of handful of high yielding varieties have also reduced the genetic diversity. Potatoes are highly valuable, nutritious vegetable and major cash crop grown in Gilgit-Baltistan (GB) Pakistan. Recently early blight disease has severely infected the potato fields of Nomal valley of GB. Early blight is an important foliar disease under diverse climatic conditions of GB. Over the past few years, early blight became a major threat to potato crops in GB and highest incidences were recorded in Nomal Valley of GB. Nomal Valley has been divided into six major sectors or Mohallahs. The Mohallahs are as; Mohallah Jigot, Mohallah Batot, Mohallah Majini, Mohallah Das and Mohallah Sigal. During June-July, 2016 a survey were carried out in randomly selected five fields of each Mohallah of Valley Nomal. Within each field five potato plants were randomly selected and observed for typical early blight symptoms. Moreover at harvesting stage tubers were also observed for early blight symptoms. The disease incidence and disease severity were recorded. The highest percent disease severity (66.4) was recorded in potato fields of Mohallah Jigot followed by potato fields of Mohallah Sigel (63.2%), Mohallah Majini (42%) and Mohallah Batot (36%). Meanwhile the minimum percent disease severity was recorded on the potato fields of Mohallah Das (12%). It can be concluded from the present study that early blight is serious threat to potato production in Nomal Valley of GB.