Exploring the Potential of Meyerozyma guilliermondii on Physiological Performances and Defense Response against Fusarium Crown Rot on Durum Wheat

Abstract

Coating seeds with bio-control agents is a potentially effective approach to reduce the usage of pesticides and fertilizers applied and protect the natural environment. This study evaluated the effect of seed coating with Meyerozyma guilliermondii, strain INAT (MT731365), on seed germination, plant growth and photosynthesis, and plant resistance against Fusarium culmorum, in durum wheat under controlled conditions. Compared to control plants, seed coating with M. guilliermondii promoted the wheat growth (shoot and roots length and biomass), and photosynthesis and transpiration traits (chlorophyll, ɸPSII, rates of photosynthesis and transpiration, etc.) together with higher nitrogen balance index (NBI) and lower flavonols and anthocyanins. At 21 days post infection with Fusarium, M. guilliermondii was found to reduce the disease incidence and the severity, with reduction rates reaching up to 31.2% and 30.4%, respectively, as well as to alleviate the disease damaging impact on photosynthesis and plant growth. This was associated with lower ABA, flavonols and anthocyanins, compared to infected control. A pivotal function of M. guilliermondii as an antagonist of F. culmorum and a growth promoter is discussed.

Comparative Performances of Beneficial Microorganisms on the Induction of Durum Wheat Tolerance to Fusarium Head Blight

“…Moreover, they all promoted the photosynthetic processes depicted by higher green leaf area (NDVI) and chlorophyll content (SPAD). The performance of M. guilliermondii and T. harzianum under field conditions aligned with our previous studies demonstrating their potential in inducing plant resistance against F. culmorum under controlled conditions [11,16]. In more detail, the seed coating with T. harzianum S.INAT was found to apply, under controlled conditions, to both the direct antagonist activity and indirect growth promotion and induced systemic resistance of wheat plants against foot crown rot disease [16,17].…”

“…Biostimulants are considered as products modifying biochemical and physiological processes in plants, neutralizing the adverse impact of weather conditions and reducing the occurrence of diseases by stimulating plant growth, strengthening plant defense and improving nutrition efficiency leading to sustainable crop yield [24]. In our preceding experience under controlled conditions, the seed coating with Meyerozyma guilliermondii and T. harzianum S.INAT was found to achieve the seed priming state of seeds and induce plant resistance against F. culmorum [11,16]. Seed priming with a biostimulant is an effective pre-germination physiological method that induces structural and ultra-structural modifications and a change in plant hormone biosynthesis.…”

“…Before sowing, the seeds were coated with M. guilliermondii INAT (KU710283), T. harzianum (KU710282), and the combination M. guilliermondii-T. harzianum as described previously [11,20].…”

“…An alternative approach is the application of seed coating with beneficial microorganisms, which might be able to (i) counteract the pathogenic and mycotoxigenic potential of natural populations of Fusarium surrounding the seed in infected soils, (ii) induce systemic plant resistance against pathogens [10] and (ii) maintain the symbiotic relationship between beneficial microorganisms and the plant along the growth cycle. In fact, seed biopriming using beneficial microorganisms as seed coating agents was used to induce germination, improve the emergence of seedlings and induce mechanisms of plant disease resistance [11,12] Meyerozyma guilliermondii is a yeast reported as a biocontrol agent and inducer of plant resistance [13,14]. Trichoderma harzianum is a beneficial fungus known for its biocontrol capacity against soil-borne pathogens and its ability to trigger plant growth [15,16].…”

“…In our previous study, we reported that seed coating with M. guilliermondii and T. harzianum S. INAT stimulate seed germination, induce plant resistance against F. culmorum and improve plant growth and photosynthesis in durum wheat under controlled conditions [11,16,17]. Despite their potential under controlled conditions, their biocontrol efficiency against FHB disease of durum wheat under field conditions could be less impressive.…”