Interaction studies of Serendipita indica and Zhihengliuella sp. ISTPL4 and their synergistic role in growth promotion in rice

Abstract

Rapid urbanization and globalization demand increasing agricultural productivity. Soil nutrient supply capacity is continuously decreasing due to soil erosion, degradation, salt deposition, undesired element, metal deposition, water scarcity, and an uneven nutrient delivery system. Rice cultivation requires a large amount of water which is becoming detrimental due to these activities. There is a need to increase its productivity. Microbial inoculants are becoming increasingly important in achieving sustainable agricultural production systems. The current study was conducted to investigate the interaction between the root endophytic fungus Serendipita indica (S. indica) and the actinobacterium Zhihengliuella sp. ISTPL4 (Z. sp. ISTPL4) and their synergistic effects on the growth of rice (Oryza sativa L). Both S. indica and Z. sp. ISTPL4 showed positive interactions. Growth of S. indica was observed at different days after Z. sp. ISTPL4 inoculation, and stimulated growth of S. indica was observed when Z. sp. ISTPL4 was inoculated at 5 dafi (days after fungal inoculation). Z. sp. ISTPL4 promoted the growth of S. indica as it increased spore germination. Furthermore, confocal and scanning electron microscopy (SEM) analyses showed a 27% increase in the spore size of S. indica in the presence of Z. sp. ISTPL4. In a liquid chromatography with tandem mass spectrometry (LC-MS/MS) analysis increased production of alanine and glutamic acid was observed in their sequential co-culture as compared with individual cultures. Sequential inoculation of S. indica and Z. sp. ISTPL4 significantly increased the biochemical and physical characteristics of rice as compared with their individual inoculum. Biochemical parameters such as chlorophyll content, total soluble sugar, and flavonoid content in the rice increased by up to 57%, 47%, and 39%, respectively, in the presence of the combined inoculum of S. indica and Z. sp. ISTPL4. This will be the first study, to the best of our knowledge, which shows the fungus and actinobacterium interaction and their synergistic roles in the growth promotion of rice. Furthermore, this novel combination can also be used to boost the growth of other crops to increase the agricultural yield.

Fungal-Bacterial Combinations in Plant Health under Stress: Physiological and Biochemical Characteristics of the Filamentous Fungus Serendipita indica and the Actinobacterium Zhihengliuella sp. ISTPL4 under In Vitro Arsenic Stress

“…ISTPL4 was also determined under normal growth conditions which indicated an increased spore size and germination of S. indica in the presence of Z. sp. ISTPL4 than its respective control ( S. indica ) [ 14 ].…”

“…The concentration of arsenic used was up to 2.4 mM [ 16 ]. Dry cell weight of S. indica alone and in combination was estimated (control and treated cultures) to check the effect of arsenic on the growth of S. indica [ 14 ].…”

“…The final step was repeated three times in 100% ethanol for 5 min each. Resulting samples were dehydrated, air dried and placed in aluminum double adhesive carbon conductive tape gold-coated specimens in a Quorum Q150ES coater and then observed under a scanning electron microscope (model Zeiss EVO 18; Raipur, India) [ 14 ].…”

“…The interaction between Zhihengliuella sp. ISTPL4 and S. indica has been previously reported in a systemic study [ 14 ]. The role of this microbial combination has also been deciphered in plant growth promotion.…”

Synergistic impact of Serendipita indica and Zhihengliuella sp. ISTPL4 on the mitigation of arsenic stress in rice

“…ISTPL4 was checked at varying range of As (0.2, 0.9, 1.4, 1.9, 2.4, and 2.6 mM), to examine the effect of As on their growth. Medium used for their growth was Hill and Kaefer agar in 10.3389/fmicb.2024.1374303 Frontiers in Microbiology 03 frontiersin.org combination with Luria-Bertani agar (1:3) (Hill and Kafer, 2001;Sharma et al, 2023Sharma et al, , 2024.…”