Global zinc deficiency is a major problem today, and the Philippines is among the countries with widespread soil zinc deficiency. To address this challenge, the National Institute of Molecular Biology and Biotechnology-University of the Philippines Los Baños (BIOTECH-UPLB) developed microbial inoculants for rice and corn. 

University researcher Robert A. Nepomuceno talked about these microbial inoculants during the DA-BAR’s monthly webinar on 22 June 2023 conducted via StreamYard and Facebook Live. He also discussed the microbial inoculant developed to sustainable combat cassava phytoplasma disease (CPD).

Microbial inoculants are intended to increase crop yield, enhance nutrient availability in the soil, improve uptake of plant nutrients, promote plant growth, stimulate biological processes in the soil, restore the soil’s natural fertility, act as a biological control agent against pests, and pathogens, and reduces the application of chemical fertilizers and production cost.

“These inoculants are eco-friendly,” Nepomuceno added. 

He proceeded to explain the purpose of the three microbial inoculants featured in the webinar. First on the list was Oryzinc, which is an inoculant designed specifically for rice.

“It contains zinc solubilizing bacteria, converts zinc in the soil into a form that plants can absorb, and decreases the zinc chemical fertilizer application in lowland rice, a crop sensitive to zinc deficiency,” he said. 

In vivo screening of top zinc solubilizing isolates shows that plants treated with the bacterial isolates show comparable results with the positive control. 

Second, Maizinc was designed specifically for corn. It is a microbial-based inoculant that contains zinc-solubilizing bacteria, converts zinc in the soil into a form that plants can absorb, and decreases the zinc chemical fertilizer application in corn. 

As to how the technologies were developed, Nepomuceno explained that there were several steps in the development of these technologies, which include the isolation and screening of microorganisms, efficacy trial through field testing in different areas, optimization of conditions for the production of zinc solubilizing microorganisms (ZSM) and shelf-life studies, and mass production of inoculant and DA-Fertilizer and Pesticide Authority registration and field demonstration.

Part of the process was gathering feedback across farms from operators and stakeholders indicating their satisfaction and increase in crop growth because of the application of microbial inoculants for rice. Nepomuceno said that the application of Oryzinc contributes to rice resilience toward rice sufficiency. He further said that it has a greater yield as compared to the control. Also, the local products were promoted to the farmers, who were educated about their usage and application.

“Oryzinc and Maizinc could help address the problem of insufficiency of rice and corn crops,” Nepomuceno said.

Lastly, he discussed Bioplasma which is a microbial-based inoculant when supplemented with VAMRI, prevents the occurrence and regulates the severity of CPD. It promotes the growth of both healthy and CPD-infected cassava.  Nepomuceno explained “VAMRI or Vesicular-Arbuscular Mycorrhizal Root Inoculant is composed of Glomus mosseae and fasciculatum and is capable of replacing 50-100% of the plant’s chemical fertilizer requirement and has been reported to confer disease resistance against soil-borne phytopathogens.”

Before the webinar ended, Nepomuceno underscored that there is an urgent need for the upscaling of the production of the technologies for nationwide utilization for organic agriculture, food security, and sustainable agriculture.