EVALUATION OF SOURCES OF PLANTING MATERIAL OF SWEETPOTATO (Ipomeoa batatas, L) VARIETIES ON FIELD PERFORMANCE AND VIRAL LOAD

Abstract

Sweetpotato is an important crop for food security in many developing countries. Studies have shown virus diseases threat to the crop consistently and yet they remain the most difficult diseases to manage. The contributing factors to yield reductions in sweetpotato are insects and disease with viruses being the major cause of yield reduction. There are at least 15 well known characterized viruses. The aim of this research is to evaluate the field performance of three sources of planting material of some varieties and their virus status. The sources of planting material were in vitro generated platelets, Farmer’s own materials and Field symptomless materials. Planting materials of four sweetpotato varieties, Apomuden, Bohye, Ligri and Dadanyuie were used. The trial was laid out in split plot design with the sources of planting material allocated to main plots and the varieties to sub-plots. The in vitro indexed plantlets were obtained from Biotechnology laboratory of Crop Research Institute, Fumesua. The Other two sources were obtained from International Potato Center CIP, Tamale. Nitrocellulose Membranes Enzyme Linked Immunosorbent Assay (NCM-ELISA) kits were employed for the detection of 10 sweetpotato viruses. After the serological reactions, SPFMV, SPMMV, SPMSV, SPCFV, SPCSV, and CMV indicated significant presence among the different sources of planting materials whilst SPC-6Vvirus,SPVG, SPCaLV and SPLV were negative. Farmer source of planting material recorded the highest virus symptoms. Apomuden and Bohye varieties recorded the highest virus score in the first and second virus symptom observational score respectively. Tissue culture in vitro materials recorded highest chlorophyll content.Vine yield was highest among the in vitro source of material. in vitro plantlets showed significant higher tuber root yield and other yield parameters than other sources of planting material. In the absence of in vitro generated material farmers will be advised to use field materials that have been selected mindful of virus symptoms.