The Effect of Seed-borne Mycoflora from Sorghum and Foxtail Millet Seeds on Germination and Disease Transmission

Abstract

The seed-borne mycoflora of sorghum and foxtail millet collected from different growing areas in South Korea were isolated and taxonomically identified using dry inspection, standard blotter and the agar plate method. We investigated the in vitro and in vivo germination rates of disinfected and non-disinfected seeds of sorghum and foxtail millet using sterilized and unsterilized soil. The percent recovery of seed-borne mycoflora from the seed components of sorghum and foxtail millet seeds was determined and an infection experiment using the dominant species was evaluated for seedling emergence and mortality. A higher number of seed-borne fungi was observed in sorghum compared to that of foxtail millet. Eighteen fungal genera with 34 fungal species were identified from the seeds of sorghum and 13 genera with 22 species were identified from the seeds of foxtail millet. Five dominant species such as Alternaria alternata, Aspergillus flavus, Curvularia lunata, Fusarium moniliforme and Phoma sp. were recorded as seed-borne mycoflora in sorghum and 4 dominant species (Alternaria alternata, Aspergillus flavus, Curvularia lunata, Fusarium moniliforme) were observed in foxtail millet. The in vitro and in vivo germination rates were higher using disinfected seeds and sterilized soil. More seed-borne fungi were recovered from the pericarp compared to the endosperm and seed embryo. The percent recovery of seed-borne fungi ranged from 2.22% to 60.0%, and Alternaria alternata, Curvularia lunata and 4 species of Fusarium were isolated from the endosperm and embryo of sorghum and foxtail millet. Inoculation of the dominant seed-borne fungi showed considerable mortality of seedlings. All the transmitted seed-borne fungi might well be a primary source of infection of sorghum and foxtail millet crops.

Sanitary analysis, transmission and pathogenicity of fungi associated with forage plant seeds in tropical regions of Brazil

“…In general, other studies report the susceptibility of these grasses to attacks of fungi from genre Bipolaris, Exserohilum and Curvularia, which cause spots in leaves and stalks, besides drying the leaves and killing the seedlings (Macedo and Barreto, 2007;Martinez et al, 2010;Kleczewski et al, 2012;Braz et al, 2013;Kumar et al, 2013), however, some authors realized that this result may vary in accordance with the genotype used (Braz et al, 2013). Yago et al (2011) observed that there was an increase in the seedling death percentage for sorghum and foxtail millet seeds inoculated with Curvularia lunata and increase in the severity index for infected seedlings 10 days after the inoculation.…”

“…The presence of fungi on vegetal tissues was also reported by Yago et al, (2011) who studied sorghum and foxtail millet seeds and identified Curvularia sp. on the seeds' endosperm and Alternaria and Fusarium on the seeds' endosperm and embryo.…”

Alternaria alternata: A new seed-transmitted disease of coriander in South Africa

“…Appearance of Alternaria leaf spots on coriander in naturally infected, non-inoculated pots in greenhouse trials and seed transmission experiments proved its seed transmission. Similarly, A. alternata has been reported as seed-borne and seed-transmitted in maize, sorghum, foxtail millet and many other hosts (Basak and Lee, 2002;Fakhrunnisa and Ghaffar, 2006;Yago et al 2011;Meena et al 2013;Perelló and Larrán, 2013).…”

Effect of cupric oxide and zinc oxide nanoparticles on seed mycoflora and seed quality of fodder crops

“…Seeds with high initial vigour, foliage growth and good germination provide more biomass and also provides edge to weed competition in their natural growth conditions (Maity et al, 2016). One of the main impediments towards the availability of good quality seeds is seed borne pathogens (Naqvi et al, 2013;Kononenko et al, 2015), which account for annual economic loss of more than US $130 million in Afro-Asian countries (Yago et al, 2011). They reduce seed viability by associating with the seed either externally or internally and may cause seed abortion, seed rot, seed necrosis and reduction or elimination of germination capacity as well as seedling damage.…”