Isolation and characterization of Aspergillus niger NBC001 underlying suppression against Heterodera glycines

Abstract

Heterodera glycines is the most pervasive soybean pests worldwide. Biocontrol provides a strategy to sustainably control nematodes. In this study, 22 fungal isolates were obtained and identified from cysts of Heterodera spp. Among them, Aspergillus niger NBC001 showed high nematicidal activity against H. glycines. The 2-fold dilution of NBC001 culture filtrate caused 89% mortality of second-stage juveniles and inhibited more than 98% of egg hatching in vitro. In both pot and field experiments, the numbers of H. glycines cysts in soybean seedlings dressed with the the 5-fold concentrated culture filtrate of NBC001 were significantly reduced by 43% and 28%, respectively. In addition, application of NBC001 remarkably reduced the penetration of nematodes into the roots. Histochemical and fluorometric staining analyses indicate that application of NBC001 stimulated hydrogen peroxide activity in the roots and triggered callose deposition in the leaves and roots. Transcription of the PR1a and EREBP genes in the salicylic acid and ethylene signaling pathways was upregulated in soybean plants treated with NBC001. However, the application of concentrated culture filtrate of NBC001 had no significant impacts on the soil microbial community based on next generation DNA sequencing technology. In summary, NBC001 may be a good biocontrol agent against H. glycines via stimulation of the immunity/defense of the plant host.

Nematicidal Evaluation and Active Compounds Isolation of Aspergillus japonicus ZW1 against Root-Knot Nematodes Meloidogyne incognita

“…Aspergillus spp. are very common in soil and are lethal to the nematode population; A. niger and A. candidus were the potential fungal agents to be used against plant-parasitic nematodes [35,42,43]. The results of this study indicated that fermentation of the A. japonicus ZW1 from soil was found to not only inhibit egg hatching but was also toxic to nematodes in vitro.…”

Bioprospecting of Rhizosphere-Resident Fungi: Their Role and Importance in Sustainable Agriculture

“…Crop plants encounter different abiotic stress challenges—including excessive temperature, drought, salinity, floods, and heavy metal accumulation—which exclusively affect crop plant growth and yield [ 201 , 202 ]. Most cultivated lands face one or more of the above-listed stresses, which decrease crop plants’ yields by up to 70% [ 203 ].…”

Aspergillus spp. eliminate Sclerotinia sclerotiorum by imbalancing the ambient oxalic acid concentration and parasitizing its sclerotia

“…It has been extensively used for controlling white mould in oilseed rape, cabbage, soybean, common bean, and other important cash crops (Steadman, 1979; Jones et al ., 2014; Zhang et al ., 2016; Hu et al ., 2016b; Sabaté et al ., 2018). Mycoparasitic potential of Aspergillus against broad range of plant pathogenic fungi, bacteria and nematodes was previously demonstrated (Israel and Lodha, 2005; Patibanda and Sen, 2005; Adebola and Amadi, 2010; Jang et al ., 2016; El‐Debaiky, 2017; Alshannaq et al ., 2018; Boughalleb‐M'Hamdi et al ., 2018; Jin et al ., 2019). The mechanisms by which Aspergillus can eliminate the opponent fungal pathogens were studied.…”