EFFECT OF Phytophthora LEAF BLIGHT DISEASE OF TARO [Colocasia esculenta(L.) Schott] ON PROXIMATE AND PHYTOCHEMICAL CONSTITUENTS OF INFECTED CORMS

  • F.N. Ugwuja Department of Plant Science and Biotechnology, Michael Okpara University of Agriculture, Umudike
  • T.J. Onyeka National Root Crop Research Institute, Umudike
Keywords: Healthy Tissues, Diseased Tissues, Taro Corms, Proximate, and Phytochemical

Abstract

Leaf-blight and corm rot of taro [Colocasia esculenta (L.) Schott] incited by Phytophthora colocasiae hampers
production, storage and utilization of taro in Nigeria. This study evaluated the effect of leaf blight disease on
proximate and phytochemical constituents of infected corm varieties: NCe001, NCe011, NCe012 and BLS/158
obtained from National Root Crops Research Institute (NRCRI) Umudike, and grown under natural leaf blight
disease conditions during the 2016/2017 planting season. The experiment was laid out in Randomized Complete
Block Design and replicated thrice. Corm samples were obtained from the infected and uninfected crop after
harvest and analyzed for proximate and phytochemical constituents by standard procedures. Data were subjected
to Analysis of Variance (ANOVA). Results showed significant (P< 0.05) reduction in carbohydrate, dry matter,
crude fibre, ash, crude fat and energy value in the diseased samples of the varieties compared to the healthy
samples. However, significant (P< 0.05) higher moisture and crude protein contents were observed across the
diseased taro varieties. Oxalate, Flavonoids and Tannins had significant (P < 0.05) higher values for non-diseased
samples over the diseased samples and varied among the varieties. Alkaloids and Saponins were higher in the
diseased samples and varied significantly. The significant reduction in proximate and phytochemical constituents
of infected corms demonstrated in this experiment suggests that taro leaf blight (TLB) caused significant
reduction in the chemical composition of taro corms and may limit the industrial potentials of corms. Hence, taro
based industries are by this findings informed of the magnitude of nutrient depletion in infected taro corms due to
blight and the need to make necessary adjustments to avoid the production of sub-standard products.

Published
2020-04-30

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eISSN: 0300-368X