Strategies to Control Phosphine Resistance in Rhyzopertha dominica Infesting Cereal Crops

Rahul Chandel1, S Subramanian1, Machiavelli Singh2, Manju Sharma2*

1Division of Entomology, Indian Agricultural Research Institute, New Delhi, 110012, India.

2Amity Institute of Biotechnology, Amity University Haryana, Manesar, Gurugram 122413, Haryana, India.

*Corresponding author email: msharma@ggn.amity.edu

Abstract

Providing safe food to burgeoning population of the world is biggest challenge to date. Besides, growing enough food grains postharvest management is biggest challenge for the farmers and agriculture scientists. In storage grains are prone to loss by rodents, insects, mites, birds and microorganisms. As per the Pansay Committee report, the standard storage losses were estimated 2.5 percent caused due to infestation of insects in centrally stored grains. Rhyzopertha dominica commonly known as lesser grain borer considered most devastating to acquisition of resistance, as it coevolves and develop resistance with methods used to control them. Phosphine fumigation has been the most effective in controlling R. dominica but the pest is acquiring resistance against phosphine and is matter of concern at international level. The genetic basis for development of resistance was explored. A single amino acid substitution from P to S which provides strong resistance in T. casteneum and R. dominica was a result of a single common base substitution of C122T in the coding region of T. casteneum and a C145T in R. dominica. As a result, CAPS markers were designed to identify such SNPs for these beetle species. The fumigation of godowns without proper sealing one of the major reasons led to frequent under-dosing, inadequate exposure time and lack of airtight situations, thus led to the resistant in population of insects Therefore, immediate attention is needed for protection of stored produce from degradation of quality and weight loss during storage period.

Keywords: Wheat, Rhyzopertha dominica, Phosphine, Molecular screening, Phosphine resistance