Endomycorrhizal Fungi and <i>Opuntia ficus-indica</i> Seed Germination on a Lunar Regolith Simulant

Abstract

Endomycorrhizal fungi play an important role in the survival of plants on poor soils. Planting seeds into lunar soil at a lunar colony will be a challenge for seeds of any plant. The seeds will need a special microbial "tool kit" that will help them germinate and the young seedlings establish themselves. In this study, seeds of the prickly pear cactus, Opuntia ficus-indica, were chosen to examine the presence of fungus spores in the soil, inside the seeds and after germination in the rhizosphere, roots and other tissues of the young seedlings. The nutrient poor lunar regolith simulant JSC-1A was used as autoclaved or untreated growth medium. The mycorrhizal fungus Trichoderma viride was predominantly identified on the roots of new seedlings. This fungus also demonstrated the strongest effect on the germination rate of the seeds in comparison with other fungi isolated from the rhizosphere of Opuntia plants. T. viride was not detected within seeds and also not within seedlings, besides the root tips, whereas an arbuscular mycorrhizal Glomus species was seed-borne and present throughout most of the seedling. A close association between T. viride and a Glomus species associated with O. ficus-indica is demonstrated through light microscopic and electron microscopic images of the outside and inside root tips of the seedlings.

Increasing the pepper seed quality using mycorrhizal fungi

“…First count The treatment of spice pepper seeds with the biostimulant Coveron increased the percentage of normal seedlings at the first (Table 2) and final counts (Table 3) compared to the control. In this study, two Glomus strains and one Trichoderma strain enhanced early germination and the total germination percentage, which is consistent with the results of a number of researchers obtained for different plants (Hanson 2000;Mishra and Sinha, 2000;Oyarbide et al 2001;Islam et al, 2011;Konings-Dudin et al, 2014). In the first experimental year, the first count and total germination of the pepper seeds examined increased by 4 -6 % in the seeds treatment with the biostimulant Coveron, compared to the control.…”

The changes in seed quality of selected pepper varieties in three years

“…In contrast, the maximum germination was obtained in samples where the prevalence of pathogenic fungi is lowest (Debnath et al, 2012). Also, using Trichoderma, strain germination and total germination may be increased (Konings-Dudin et al, 2014;Murphy., 2017). Our samples were not treated, and total germination was obtained from natural seeds, which indicates the possibility of increasing germination by applying some organic treatments.…”