COMPARISON OF FIELD PERFORMANCE BETWEEN DASHEEN MOSAIC VIRUS-FREE AND VIRUS-INFECTED IN VITRO PLANTS OF COCOYAM (XANTHOSOMA SPP.) IN NICARAGUA

Abstract

Cocoyam (Xanthosoma spp.) is the most important export crop of all the root and tuber crops grown in Nicaragua. Despite its importance, the total planted area and yield have significantly decreased during the past few years, a decrease that is mainly due to diseases that are disseminated through the planting material. In this study virus-free (NI) and virus-infected (I) in vitro plants from three genotypes were established in a non-traditional production area. The aim was to evaluate their agronomic performance, and to study the re-infection of dasheen mosaic virus (DsMV) and its effect on yield. Repeated measurements of morphological traits were made during the experimental period. The height of the plants, the diameter of the pseudo-stem and the leaf area increased continuously up to 217 days after planting after which the growth curves declined. The genotypes differed in all yield components, except in yield per plant. Regardless of genotype, the NI plants produced a larger number of cormels that were heavier and longer than the cormels produced by I plants. This resulted in a higher yield from NI plants (18.2 t ha−1) compared with I plants (13.6 t ha−1). Seven months after planting between 60 and 90 % of the NI plants, depending on genotype, were infected with DsMV. Aphis gossypii was the only aphid observed in the field trial and is therefore most probably the vector responsible for the transmission of the virus.

Incidence of RNA viruses infecting taro and tannia in East Africa and molecular characterisation of dasheen mosaic virus isolates

“…Infection typically results in a characteristic feathery mottle and mosaic symptom on the leaves, but symptoms may vary considerably between cultivars and season of the year (Alconero & Zettler, 1971 ; Elliott et al, 1997 ). DsMV infection is reported to affect both the quality and quantity of the edible corms, with production losses of more than 25% (Reyes, Rönnberg‐Wästljung, & Nyman, 2006 ; Valverde et al, 1997 ).…”

Micro-propagation of Colocasia esculenta (cv. Bolosso I) from corm and sprout tip explants

“…Even though taro has many roles, its propagation and ultimate production is adversely affected by biotic stresses and nature of the plant itself (Singh et al, 2012). Lack of improved varieties, and need of large planting materials (Onokpise et al, 1999), rare natural flowering and seed setting (Mbouobda et al, 2007), transmission of pathogens particularly dasheen mosaic virus (DsMV) during vegetative propagation which can cause yield loss up to 90% or may cause loss of genotypes (Reyes et al, 2006;Nassar et al, 2007;Beyene, 2012) are major constraints of taro and its relate, tannia production. Beyene (2012) reported that 36.9% of the taro samples found to be positive to DsMV specific antibodies out of 295 symptomatic and non-symptomatic taro leaf samples which were collected from major growing areas of south and southwest Ethiopia.…”

First Molecular Characterization of the Partial Coat Protein and 3’utr Genes Related to Dasheen Mosaic Virus on Flamingo Flowers (Anthurium Species) in the Mediterranean Coast of Turkey

“…In another group of studies, presence of DsMV with molecular techniques was detected by Reyes et al (2009)…”