A profitable function of Ceriporia lacerata HG2011 on nodulation and biological nitrogen fixation of green bean (Phaseolus vulgaris L.).

AIMS: Green bean (Phaseolus vulgaris L.) is a popular vegetable worldwide. The use of beneficial fungi is a simple and effective way to improve the biological nitrogen fixation (BNF) of this leguminous vegetable. METHODS AND RESULTS: A micro-plot was conducted to investigate the enhancement of BNF using 15N natural abundance technology and agronomic performances of green bean caused by wood-rot fungus Ceriporia lacerata HG2011. The results showed the soil for frequently growing green bean featured abundant native rhizobia, and newly inoculated rhizobia may have to compete with them in nodulation and only highly competitive rhizobia can succeed. The addition of C. lacerata HG2011 to the soil increased the population of ammonia oxidizers, nitrifiers, and phosphorus (P)-mobilizing microbes in rhizosphere, accelerated nitrification and P mobilization, creating a favorable soil environment with high P and low ammonia for BNF. Green bean received C. lacerata HG2011 had higher dehydrogenase activity in roots and higher nodulation rate and large nodules. These phenomena implied abundant supplies of adenosine triphosphate, nicotinamide adenine dinucleotide hydrogen, or nicotinamide adenine dinucleotide phosphate hydrogen for BNF in the roots, a large proportion of N2 fixation tissues, and a greater sink for receiving photosynthates. As a result, C. lacerata HG2011 considerably increased the percentage of N derived from the atmosphere, BNF, and plant nutrient uptake (including N, P, and potassium), leading to 15.58%-28.51% of biomass increasment and 9.82%-17.03% of peapod yield increasment along with quality improvement compared with non-fungal application. CONCLUSIONS: C. lacerata HG2011 increased the nodulation and BNF of green bean, accelerated the nutrient uptake (NPK) and therefore improved the yield and peapod quality of green bean. SIGNIFICANCE AND IMPACT OF STUDY: The study demonstrates that C. lacerata HG2011 could be used as a biofertilizer for BNF improvement of legumes.

Ceriporia lacerata HG2011 enhances P mobilization and wheat agronomic performance irrespective of P fertilization levels.

AIMS: To identify soil phosphorus (P) mobilization and wheat agronomic performance in response to the P mobilizer Ceriporia lacerata HG2011 could provide a new strategy for improving fertilizer P efficiency in wheat cultivation. METHODS AND RESULTS: Liquid culture showed that C. lacerata HG2011 converted Ca3 (PO4 )2 , FePO4 , AlPO4 , phytate, lecithin and ribonucleic acid into soluble inorganic P, which was stimulated by ammonium and urea but less influenced by P supply. In the incubation experiment, this fungus colonized on wheat roots, and mobilized P in the soils regardless of Olsen P levels. The efflux of protons, organic acids and phosphatase could be involved in insoluble P mobilization. In the greenhouse pot experiment, C. lacerata HG2011 increased soil Olsen P under different P fertilization levels, improved wheat P uptake by 15.39%-28.70%, P fertilizer use efficiency by 4.26%-13.04% and grain yield by 12.24%-22.39%. CONCLUSIONS: Ceriporia lacerata HG2011 was able to colonize on wheat roots, mobilize P in soils and improve wheat agronomic performance irrespective of P fertilization levels. SIGNIFICANCE AND IMPACT OF THE STUDY: Ceriporia lacerata HG2011 could be used to enhance the quality of compost or as a bio-fertilizer for P mobilization in modern sustainable agriculture.

A new function of white-rot fungi Ceriporia lacerata HG2011: improvement of biological nitrogen fixation of broad bean (Vicia faba).

The inoculation of plant growth-promoting microbes with multifarious functions is a simple, economic, and effective way to improve nodulation and biological nitrogen fixation (BNF) of legumes. Broad bean (Vicia faba) is commonly grown in the winter in tropics and subtropics for increasing soil N and farmers' income. The new functions of Ceriporia lacerata HG2011, a white-rot fungus, in nodulation and BNF (measured by 15N natural abundance) were studied with the broad bean in liquid culture, soil incubation, and greenhouse pot experiments. The results showed that this fungus released IAA, GA, and Fe-binding ligands into culture solutions, increased lateral roots and root surfaces, and mobilized phosphorus and iron into bioavailable forms in the soil. These performances may be beneficial to nodulation and BNF. The indigenous rhizobia that infect broad been were long-lived in the experimental soil. The efficiency of exogenous rhizobium inoculation may be unsatisfactory in the soils for frequently growing broad beans because of fierce competition with native rhizobia. Compared with no inoculation, the fungal inoculant increased nutrient (nitrogen, phosphorus, and potassium) availability in the fertilized soil, nodule mass, and plant BNF and nutrient uptake, leading to higher plant biomass and grain yield. Thus, C. lacerata HG2011 provided more potential sites for rhizobia infection in nodulation, increased nodule size, and improved nodule mineral nutrient (particularly phosphorus and iron) and photosynthate acquisitions, resulting in better nodulation and increased plant BNF. These significant findings firstly proved a new function of C. lacerata HG2011 in improving the inoculation and BNF of legume plants.

Phosphorus mobilization and improvement of crop agronomic performances by a new white-rot fungus Ceriporia lacerata HG2011.

BACKGROUND: Some soil microorganisms can mobilize unavailable phosphorus (P) in soils for plant use and increase P fertilizer efficiency. Thus, an abiotic P solubilization experiment and fungal incubation in solution and soil were conducted to investigate the mobilization of various P compounds by a new white-rot fungus Ceriporia lacerata HG2011. The crop agronomic performances were then evaluated in the winter barley-summer maize-winter wheat rotation field. RESULTS: Ceriporia lacerata HG2011 had a wide P mobilization spectrum and mobilized P by different mechanisms depending on P sources supplied in liquid culture. The chief mechanism employed by this fungus was the production of protons in mobilizing Ca3 (PO4 )2 , low-molecular-weight organic acids and other unknown substances in FePO4 and AlPO4 , phytase (an inducible enzyme in the presence of phytate) in phytate, and phosphatase in lecithin and ribonucleic acid, respectively. As a result of the large fungal biomass, P accumulated in the hypha should also be considered in the assessment of the fungal P mobilization, and not just only soluble inorganic P. As C. lacerata HG2011 colonized on and in the test soil, phosphatase and phytase activities were enhanced but pH decreased in the soil, leading to P mobilization. The application of this fungus mobilized soil P, increased crop P uptake and yields, and consecutively reduced P fertilizer use without yield sacrifices in the multiple crop rotation field. CONCLUSION: C. lacerata HG2011 showed a new use with respect to mobilizing soil P and reducing P fertilizer input in modern agriculture beyond medical purposes, environmental protection and biofuel production. © 2021 Society of Chemical Industry.

[Effect of biopesticide Pythium oligandrum broth on gummy stem blight in cucumber seedlings, animal health and plant growth].

Objective: Biopesticides are safe and environment friendly. We evaluated the biocontrol effect of Pythium oligandrum broth (POB) and its toxicity to animals and plant growth. Methods: Animal, antagonist, pot, and field experiments with mice, Mycosphaerella melonis, and cucumber seedlings were carried out to study animal toxicity, control of gummy stem blight, plant growth, fruit yield and quality with POB produced from self-isolated P. oligandrum CQ2010. Results: Mouse showed normal weight, appearances, performances and no pathogenic changes in organs and tissues with a large amount of POB supplied by lavage. The inhibition rate of POB against M. melonis was 51.95%, similar to thiophanate methy (800 times dilution) but much higher than chlorothalonil (200 times dilution). Malondialdehyde concentration was reduced whereas activities of peroxidase and superoxide dismutase were stimulated in seedling leaves irrespective of POB supplied before and after pathogenic inoculation. POB also decreased the pathogenic incidence and disease index with relative control efficacy from 54.8% to 64.1%. Thus, POB could alleviate cell membrane damage caused by pathogenic microbes, stimulate physiological reactions related to disease defense, and increase disease-resistant abilities of plants. Moreover, POB increased chlorophyll content, root activity, and uptake of nitrogen, phosphorus and potassium, resulting in growth acceleration, fruit yield increment, and quality improvement. Conclusion: POB is safe to animals and could control gummy stem blight of cucumber seedlings, promote plant growth, increase fruit yield, and improve the qualities.