Physiological and Biochemical Changes in Cucurbita moschata Duch. Ex. Poir Inoculated with a Nigerian Strain of Moroccan Watermelon Mosaic Virus (MWMV): Lagenaria breviflora Isolate

Abstract

This study was carried out to determine physiological and biochemical changes in C. moschata inoculated with a Nigerian strain of MWMV isolated from Lagenaria breviflora in Calabar, Nigeria. The virus infection resulted in significant (p#0.05) reductions in plant height, leaf area and number of leaves produces with highest percentage difference of 39.3% (42 PID), 60.9% (35 PID) and 25.7% (49 PID), respectively. There was a significant (p#0.05) difference in chlorophyll content between inoculated and healthy plants. The chlorophyll content of inoculated plants at all stages of growth was lower compared with the healthy plants. Chlorophyll b content was higher than Chl a in both inoculated and healthy plants. Chlorophyll a, b and total Chlorophyll were significantly reduced in inoculated plants when compared with the healthy ones. Of the twelve photochemicals screened, alkaloids, glycosides, saponins, tannins, terpenoids, steroids, polyphenols and reducing sugars were present while phlobatanins, anthraquinones and hydroxymethyl anthraquinones were absent. Moroccan watermelon mosaic virus engendered reductions in alkaloids (32.1%), reducing sugars (42.0%), saponins (33.6%), terpenoids (25.0%) and steroids (15.0%) and increase in inoculated samples of glycosides (14.8%) and flavonoids (12.5%). Effect of MWMV on proximate compositions of C. moschata revealed significant p#0.05) reductions in lipid (25.0%) and ash (14.6%) and significant (p$0.05) increases in protein (23.4%) and fibre (10.5%). Effect of the virus on carotene, vitamin A and C were insignificant. Infection of MWMV also led to significant decreases in the contents of K (48%), Fe (28.6%), Zn (25.0%) and Mg (22.0%), while Cu recorded 100% increase in inoculated samples. Marginal increase in Ca and P were recorded in inoculated samples. Infection of MWMV on antioxidants caused significant increase in inoculated samples of hydrocyanic acid and insignificant increases in total and soluble oxalate and phytic acid. Increases recorded in the antioxidant contents in plants inoculated with MWMV resulted in reduced bioavailability of minerals in the vegetable. Reduction in chlorophyll contents in inoculated plants would be a major factor explaining poor growth of host plants with attendant reductions in mineral elements of C. moschata. Changes in physiological and biochemical parameters induced by MWMV altered vital metabolic processes of C. moschata.

Use of biocides for controlling viral diseases that attack common bean and cucumber plants

“…The maximum concentrations of total chlorophyll and protein were measured 24 hrs after the biocide treatment in both protective and curative experiments. The same results had been obtained by Anuradha et al (2015) and Mofunanya and Edu (2015). The reduction in the chlorophyll content in virus-infected plants may be due to the stimulation of some cellular enzymes like chlorophyllase (Goodman et al, 1967), or as a consequence of the effect of the virus on pigment synthesis (Balachandran et al, 1997).…”

Genetic Diversity Studies and Identification of Molecular and Biochemical Markers Associated with Fusarium Wilt Resistance in Cultivated Faba Bean (Vicia faba)

“…Infection by pathogens can cause substantial biochemical alterations leading to harmful effects on plant health. Diseases may reduce plant growth and yield (Mofunanya and Edu, 2015). Because enzymes control biochemical reactions, and their synthesis is under the control of specific gene(s), any change in the activity and/or the number of BPs would reflect the pattern of gene expression and corresponding metabolic events in the cell (Neog et al, 2004).…”

Metagenomic Analysis of Plant Viruses Associated With Papaya Ringspot Disease in Carica papaya L. in Kenya

“…This work represents the second report of MWMV in papaya worldwide. MWMV has been reported in Africa and the Mediterranean region mostly in cucurbits such as Cucurbita pepo (Yakoubi et al, 2008;Ibaba et al, 2016;Kidanemariam et al, 2019), Cucumis melo (Lecoq et al, 2001), Lagenaria bleviflora, and Adenopus breviflorus (Owolabi et al, 2012;Mofunanya and Edu, 2015). Our findings would suggest that papaya is an additional natural host for MWMV and that there could be more wild or cultivated hosts requiring further determination.…”