Unravelling The Diversity of Cherry Tomato (Solanum Lycopersicum Var. Cerasiforme) Seed Microbes and Their Effect on Seed Health

Healthy seeds are the foundation of healthy plants. Planting healthy seeds contributes to securing crop productivity and seed germplasm conservation. In this study, we have identified microbes associated with seeds of three cherry tomato genotypes and demonstrated their negative effect on general seed health. Through a combined morpho-cultural and molecular characterisation (using multi-loci analysis of the ITS, β-tubulin, tef1α, and gapdh gene regions for fungi and 16s rDNA for bacteria), we have identified three fungi (Nigrospora sphaerica, N. lacticolonia, and Curvularia aeria), and two bacteria (Citrobacter freundii, and Stenotrophomonas maltophilia) from healthy-looking tomato seeds. These fungi and bacteria, through seed-soaked-inoculation, caused seed discoloration, lesions, and low germination. To our knowledge, these are the first reports of Nigrospora sphaerica, N. lacticolonia, Curvularia aeria, Citrobacter freundii, and Stenotrophomonas maltophilia on tomato seeds and demonstrated their negative impact on seed health. Seed treatment and interventions are needed to negate the possible effect of these microbes. Future studies on possible seed transmission are warranted.

Mycotoxigenic Fungi and Mycotoxins in Agricultural Crop Commodities in the Philippines: A Review

The tropical, warm, and humid conditions that are favorable to the growth and development of mycotoxigenic fungi put the Philippines at a high risk of mycotoxin contamination. To date, seven mycotoxigenic Aspergillus species, four Fusarium species, and one Penicillium species have been isolated from various agricultural crop commodities in the country. There are five mycotoxin groups (aflatoxin, fumonisin, ochratoxin, nivalenol, and zearalenone) that have been detected in both the raw form and the by-products of major crops grown in the country. Since the first scientific report of aflatoxin contamination in the Philippines in 1972, new information has been generated on mycotoxins and mycotoxigenic fungi, but little has been known of other mycotoxins until the last two decades. Further, despite the increase in the understanding of mycotoxigenic fungi and mycotoxins in the country, very limited knowledge exists on practices and measures that control both the fungi and the toxins. This paper reviews the current literature on mycotoxigenic fungi and mycotoxins in the Philippines with emphasis on the last two decades and on other mycotoxins