Two new cotton germplasm lines developed by the US Department of Agriculture (USDA) Agricultural Research Service (ARS) scientists are now available for use in safeguarding US cotton from cotton leaf curl virus (CLCuV), a whitefly-borne disease that has caused significant yield losses in the parts of Asia and Africa where the crop is grown.

Although it has not yet been reported in the United States, CLCuV disease ranks among the top 20 threats to US agriculture, according to USDA's Office of Pest Management Policy.

"Our aim is to shore-up the defenses of the US cotton crop by releasing sources of resistance to cotton leaf curl virus that our cotton breeders can readily incorporate into their variety development programs, should this disease arrive here from abroad," said Jodi Scheffler, a plant geneticist with ARS' Crop Genetics Research Unit in Stoneville, Mississippi.

Cotton leaf curl virus disease was originally identified in Africa and first reported in the Punjab region of Pakistan in 1967. The disease has since spread to other parts of the country as well as to India and China. Pakistan loses over one million bales of cotton each year due to CLCuV.

Starting in 2012, ARS researchers began sending seed shipments of their top selections to Pakistani cooperators for field testing at three sites in Pakistan's Punjab Province (Multan, Vehari and Faisalabad), where CLCuV disease has been especially severe. They also field tested seed at one location in the Sindh Province (Sakrand), where the disease been less severe.

GVS 8 and GVS 9, the new germplasm releases chosen from those field screening tests, highlight the success of the Pakistani—USA Cotton Productivity Program (CPEP)—an ongoing scientific partnership funded by the US Agency for International Development with support from the USDA-ARS Office of International Research Programs and USDA's Foreign Agricultural Service.

In addition to CLCuV resistance, the two new germplasm lines were chosen for agronomic traits, including lint yield and quality.

Source - http://www.thecropsite.com