S&T Post:Philrootcrops, IPB team up to develop disease-resistant sweetpotato varieties

Philrootcrops, IPB team up to develop disease-resistant sweetpotato varieties

By Zenaida D. Gerona
Information Officer, Leyte State University

Scientists at Leyte State University ’s Philippine Root Crop Research and Training Center or Philrootcrops based in Baybay, Leyte and the University of the Philippines Los Banos’ Institute of Plant Breeding currently work on a project that seeks to transform existing UPLB and Visayas State College of Agriculture-LSU sweetpotato varieties into disease-resistant varieties.

The research project is dubbed “Development of Sweetpotato (Ipomoea batatas) Varieties Resistant to Feathery Mottle Virus (SPFMV) Through Agrobacterium-Mediated Transformation”.

Sweetpotato is a popular cash crop in the Philippines and widely grown even in marginal areas of the country. It is an emerging industrial crop for value-added food, feeds, and starch products.

Farmers have been bothered by the devastating effect of sweetpotato viral diseases caused by SPFMV and Sweetpotato Chlorotic Stunt Virus (SPCSV). SPFMV infects sweetpotato plants synergistically with SPCSV. The infection greatly reduces sweetpotato’s yield and quality.

The infected plants show leaf-curling symptoms commonly termed as “kulot”. The disease was noted in large sweetpotato plantations in Central Luzon and Bicol region where infections resulted to significant yield decline.

SPFMV and SPCSV naturally infect Ipomea species. The former is transmitted by aphids, Myzus persicae and Aphis gossypii, and the latter by whiteflies (e.g.Bemisia tabaci and Trialeurodes abutilonea).

The problem of SPFMV and SPCSV infections perplexed scientists and farmers alike, since unlike bacterial and fungal diseases, there is yet no chemical control for these viruses. The only known control so far is eradication or use of virus-resistant varieties.

PhilRootcrops and IPB scientists, however, see eradication of infected plantations a very expensive procedure. Most cultivated sweetpotato species are susceptible to feathery mottle virus disease. Hence, the scientists see the need to transform existing sweetpotato varieties into virus-resistant varieties through genetic engineering.

Genetic engineering is viewed as more appropriate alternative to conventional breeding since sweetpotato has a hexaploid genome and it would take a long time to introduce the gene for resistance through conventional breeding.

The IPB researchers involved in the project include Dr. Vermando M. Aquino, who was replaced recently by Dr. Lolita M. Dolores as project coordinator because of his transfer to UP Diliman, and Dr. Melquides Reyes. Their PhilRootcrops counterparts are Dr. Manuel K. Palomar and Dr. Nestor L. Pido.