With a mobile phone connected to the internet, a maize farmer can have ready access to science-based recommendations on fertilizers that they can use for their crops. The DA-BAR seminar on 2 August 2022 via Facebook Live highlighted the Site-Specific Nutrient Management for Maize (SSNMM) system that provides farmers with fertilizer strategies that are very specific to their location. 

To make the system more accessible to farmers, a software named Nutrient Expert for Maize (NEM), has been developed, which serves as a tool for quickly formulating fertilizer guidelines for maize. It covers hybrid, open pollinated, and traditional varieties of maize in the Philippines. 

Jesse C. Descalsota, researcher from the University of the Philippines Los Baños, discussed that SSNMM aims to provide crop nutrient requirements based on the growing environment, increase the yield, and provide profit for the farmers while preserving the soil. 

This is to address the issue of limited farming resources and the varying soil fertility of the different fields which could greatly affect the productivity and profitability of maize farmers in the Philippines. 

Descalsota further said that usual proper nutrient management and farming practices of farmers may come from hearsays from the other farmers and some practices inherited from their ancestor, relatives, and friends leading to lower production and lesser gain. 

“The good thing is that in using SSNMM, farmers now can have access to science-based fertilizer recommendations for their respective production which will bring about more benefit and welfare to them,” Descalsota said. 

Discussing how the project came about, Dr. Apolonio Ocampo said that the existing nutrients in the field, including crop residues and manures, and the proper timing and applications of fertilizers underpin the SSNMM’s existence. 

The SSNMM is done by conducting nutrient commission trials (NOTs) in the farmers’ field to determine the attainable yield and yield response to the nitrogen, phosphorus, and potassium of the different maize varieties. 

However, he pointed out that “this method is expensive and cannot be done in every field. That’s why we developed a software that will ease the formulation of SSNMM fertilizer recommendations. This is called the Nutrient Expert Software.” 

Dr. Mirasol F. Pampolino said that the software was developed using large agronomic data sets, including those collected from on-farm field trials that were conducted in many locations across the country for many years. 

The nutrient expert recommendations follow the 4Rs nutrient stewardship concept which is applying the right source of nutrients, at the right rate, at the right time, and at the right place. 

She further enumerated, “with the use of the software and simple interview with the farmer, extension workers can easily make fertilizer recommendations that are tailored to farmers’ field conditions, as well as the fertilizer available in the fields or specific locality.” 

The software presents an economic analysis comparing the cost and benefits of the recommended practice in the farmer’s practice. It also provides information that can help farmers to decide on the level of their fertilizer investment by choosing a yield target that suits their budget or desired income and profit. 

For easy reference, Nerissa V. Paduit elaborated the Five Modules of NEM. He explained that each module requires information about the characteristics of the selected site. Software users can provide information by selecting from a list of possible answers or by entering values in designated data entry boxes. 

The first module is the Current Nutrient Management Practices  which provides an overview of the farmers’ current nutrient management practice and the yield obtained for the growing season considered. The output of the module is a summary table showing the timing of fertilizer application, amount of fertilizers applied, and their nutrient contents. 

The second module is the Planting Density Module which provides an analysis of the farmers current planting density including row spacing, within-row spacing, and number of seeds per hill. It also presents an opportunity for developing an alternative or improved planting density with options for row structure, row spacing, and within-row spacing that will result in  an optimal plant population of 65,000 to 75,000 plants per hectare. 

The third module is the SSNM Rates Module which generates the fertilizer N, P, and K requirements based on estimated attainable yield and yield responses to fertilizer. Other factors or practices affecting nutrient supply, such as the use of organic inputs, crop residue management, and management of previous crops, are also taken into account. 

The fourth module is the Sources and Splitting Module which helps the user translate the recommended NPK rates into locally available single-element or compound fertilizer sources that will satisfy the SSNM guidelines for optimal fertilizer splitting. The output of this module is a fertilizer guideline with the right rate, source, time, and place of fertilizer application tailored for the growing environment. 

The last module is the Profit Analysis Module which compares the expected or actual benefits between the farmers current practice and the recommended practice. This module also presents a ‘cost-profit scenarios’ report, which provides recommendation options based on the farmer’s budget for fertilizer. 

Other topics discussed during the webinar include: Regional SSNM Sites (Batac, Ilocos Norte; Bukidnon, Isabela, Isabela Training and Davao Training); Training on SSNM Maize, Planning and Workshop; SSNM Maize Comics; and SSNM Maize DA-CALABARZON. (### Lea Bañares-Calmada)