Perceptions on Disease and Pest Status of Major Cultivated Crops in Indian Himalayas Under Changing Climate

Agriculture in Indian Himalayan region is basically subsistence farming challenged by a variety of biotic and abiotic stresses. Himalayas are considered as chief hotspot for majority of diseases and insect-pests which are endemic in nature. In recent years, the region experienced fluctuations in disease and insect-pest scenario. Changing climatic conditions not only influence the phenology of insect-pests and diseases but also their time of appearance/emergence consequently favoring their increased spread and damage potential. Rice blast and brown leaf spot diseases of rice are endemic in nature and their occurrence in particular season depends on prevailing weather conditions owing to its severity. False smut and leaf scald diseases were considered as minor and now become major diseases for rice cultivation. In wheat, in addition to yellow and brown rust, black rust has been observed since last year. Similarly, with respect to insect-pests attacking hill crops, minor pests becoming major has become a common phenomenon. Recent past experienced an outbreak of brown plant hoppers in rice, prolonged emergence periods of whitegrubs, increased incidences of shoot flies in different crops, which clearly explains the phenomenon. The major cause of these outbreaks can be explained by the alterations in microclimate regimes which in turn under the direct influence of changing climates and altered abiotic environments experienced over the globe. This chapter reviews pest and disease dynamics in relation to the magnitude of variations observed in climatological data. The climate change experienced by Indian Himalayas is severe which is already evidenced as aberrations in rainfall, increased drought years, cold and terminal heat stresses and extreme weather events. Being biological entities, crops and associated insect pests, pollinators and diseases are bound to adjust to these anomalies. In view of this, the chapter also discusses the likely to be changes experienced by the agriculture in Indian Himalayas.