USE OF PHYSICNUT ALKALOIDS TO CONTROL ROOT-GALL NEMATODE AND TO IMPROVE MUCILAGINOUS PROPERTY AND NUTRIENT COMPOSITION OF OKRA
V. E. OGWUDIRE *
Department of Crop Science and Technology, Federal University of Technology, Owerri, Imo, Nigeria.
C. M. AGU
Department of Crop Science and Technology, Federal University of Technology, Owerri, Imo, Nigeria.
F. O. OJIAKO
Department of Crop Science and Technology, Federal University of Technology, Owerri, Imo, Nigeria.
C. O. ECHE
Nematology Unit, Department of Crop and Environmental Protection, University of Agriculture, Makurdi (UAM), Benue, Nigeria.
K. B. EZEOBIOHA
Department of Crop Science and Technology, Federal University of Technology, Owerri, Imo, Nigeria.
I. F. UMAR
Department of Crop Science and Technology, Federal University of Technology, Owerri, Imo, Nigeria.
C. B. KANU
Department of Crop Science and Technology, Federal University of Technology, Owerri, Imo, Nigeria.
I. C. OGBONNA
Department of Crop Protection and Environmental Biology, Faculty of Agriculture, University of Ibadan, Oyo, Nigeria.
K. J. NNADI
Department of Crop Science and Technology, Federal University of Technology, Owerri, Imo, Nigeria.
E. M. NWOKEJI
Department of Crop Science and Technology, Federal University of Technology, Owerri, Imo, Nigeria.
*Author to whom correspondence should be addressed.
Abstract
In the quest for a sustainable nematode control strategy, alkaloids of physic nut (Jatropha curcas) plant parts were evaluated for their nematicidal control on the root-gall nematode disease of Okra and its mucilaginous property and nutrient composition in 2019 and 2020 cropping season. The experiment was a 3×6 factorial experiments arranged in Completely Randomized Design with five replications in the screen house. Alkaloids extracted from the seeds, leaves and roots of physic nut plants were applied separately at 0, 1, 2, 3, 4 and 5 ml / potted okra plant inoculated with 1,200 infective (J2) larvae of M. incognita. Results showed that 5 ml of Root and Seed Alkaloids application significantly (P=0.05) reduced root-gall nematode infection to a gall index of 1 and 1.2 (rarely galled) when compared to the untreated control (4 -severely galled) plants thereby achieving more than 100 percent increase in mucilaginous property of okra over the control for both years of study. Moisture content, fat, calcium and sodium also increased more than the untreated control at 5 ml of root and seed alkaloids. Phosphorus and nitrogen contents were on the other hand rather enhanced by the infection. Neither Okra nor root-gall nematode infection affected ash, magnesium and potassium contents of the fruits. Nevertheless, bioactive active constituent of Physicnut plant parts such as root and seed alkaloids can thus be developed as eco-friendly non-synthetic nematicide for improved yield.
Keywords: Alkaloids, Jatropha curcas, mucilaginous property, nutrient composition, Okra, Physic nut, Root-gall nematode infection