*Corresponding author:Otusanya MO, Department of Crop protection, College of Plant Science and Crop production, Federal University of Agriculture Abeokuta, Nigeria, Email: firstname.lastname@example.org
Received: July 12, 2018; Published: July 25, 2018
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Resistance to tuber rot by Botryodiplodia theobromae in relation to tuber phenol and proximate content was investigated in this study in variety Agbodo of Dioscorea alata and varieties Oniyere, Iseosi and Abuja of D. rotundata. The four varieties harvested from a field plot where they had been fertilized with an 8-mineral content fertilizer (Bounty), were incubated with B. theobromae for 4 weeks along with their counterpart (the same four varieties) sourced from farmers’ plots. The experiment was a 4x3 factorial, with 4 main factor treatments (variety), 3 subfactor treatments of 0.6ml l-1 and 1.2ml l-1 Bounty fertilizer, and farmers’ plot tuber (FPT). There were 3 replications. Only the fertilized tubers were analyzed for phenol and mineral content in a 4 by 2 factorial experiment, as resistance to tuber infection by B. theobromae had correlated significantly with phenol and mineral uptake in white guinea yam (unpublished). Mineral fertilizer effects in infection (2.27%) and weight loss (2.11%) was evident as both were 97% lower and 67% lower respectively than those recorded for two improved Dioscorea varieties fertilized with calcium carbonate in literature. However, 0.36% (infection)/0.49% (weight loss) of FPT tubers were significantly lower than those of the fertilized tubers. Lower moisture and higher phenol content in Oniyere did not reflect in lower weight loss or infection than the other varieties. Analysis of tuber phytochemicals including phenol/phenolic compounds generally as well as minerals in the tuber which are all implicated in infection reduction should explain varietal response.