Development of Corn-based Farming System in Response to Climate Change

Development of Corn-based Farming System in Response to Climate Change

Published: 2022.11.16
Accepted: 2022.11.15
328
Asst Professor III
Research and Development Services, Northern Iloilo Polytechnic State College, Philippines
Office of Research and Development Services Northern Iloilo Polytechnic State College, Philippines

ABSTRACT

Climate impacts on corn production are due to the changing temperature and precipitation regimes in corn.  The largest impact of these changes was at the local scale where within season weather induced by the change in climate become more noticeable. The wet season results showed that corn yield increased as influenced by the package of technologies (variety, fertilizer practices and tillage) despite drastic changes in weather conditions conducted under the two cropping seasons.  Exposure to high temperatures did not affect the performance of corn, the contrasting change (decrease and increase) in yield was observed during the dry cropping season across scenarios and time periods. On the average, the decrease in corn yield of a particular variety observed were offset by the increase in corn yield observed in other varieties.  Implementing adaptation strategies could increase simulated yields by 7-15% with temperature increase. Combining experimental studies with crop simulation models would advance the farmers’ understanding of the complex interactions occurring between the biological system and the physical environment and guide them toward viable adaptation practices with potential to offset the negative impacts of climate change.

Keywords:  temperature, precipitation, package of technologies, adaptation strategies, climate change

INTRODUCTION

Corn is a crop that ideally grows in an area with distinct wet and dry season.   The crop needs light to moderate rains for more than three months for better production. Although dry weather is much favored during vegetative and flowering stage, however, high atmospheric temperature and limited soil moisture have great impact on flower pollination and corn kernel development.  Furthermore, insect pest population build up is rapid that control measures are no longer effective.  On the other hand, changes in weather pattern due to climate change also posed a threat to corn production especially on open pollinated varieties (OMA Report, 2016).

Corn is considered as the topmost important focus crop commodity in Batad, Iloilo, Philippines. There are 87 registered corn farmers in the Municipality that are very much dependent on corn production where corn planted throughout its 9,000 hectare land area (Batad OMA, 2016). The Municipality of Batad was dubbed as the “Corn Capital” of Iloilo, Philippines.   Corn is among the field crops that has been directly hit by climate change. The impact of this phenomenon not only affected the crop yield and total volume of production but also the different social and economic activities related to this crop. The shortage in supply of corn due to yield decrease will surely affect not only the town’s food production system but also the different livelihood and economic activities in which this crop is the primary input and center of trade activities.  Thus, it is imperative to develop a corn-based cropping system model, a technology that would eventually mitigate the climate change impact and address the shortage on corn production in the Municipality.

The program was funded under the Commission on Higher Education-National Agriculture Fisheries Education System (CHED-NAFES) national office in collaboration with the Local Government Unit of the Municipality of Batad (LGU), Provincial Government Environment and Natural Resources Office, Province of Iloilo (PGENRO-6) and Northern Iloilo Polytechnic State College (NIPSC), Batad Campus as the implementing institution. The program generally aimed to develop a corn-based-farming system model; a technology that could help farmers enhance the productivity of corn in the Municipality despite the changes in weather pattern.

To meet the above goal, educating the farmers was done through Farmers Field Training Program (FFTP) and hands-on participatory activities by conducting field experiments/studies (efficacy trials) at the techno-demo sites of the College in cooperation with the different agencies concerned and also with corn farmers particularly the Farmer-Scientists Training Program (FSTP) beneficiaries. Appropriate statistical tools were used in analyzing data.

Program objectives

This project aimed to: (1) determine cropping system that is most practiced by corn growers; (2) verify and adopt a corn-based cropping system suitable to existing climatic conditions in Batad, Iloilo; (3) formulate location specific technology for different indigenous vegetables (IVs) and drought tolerant crops in a corn-based farm; and (4) evaluate/determine the impacts of these farming systems to farm productivity and micro-climate.

METHODOLOGY

The corn farmer beneficiaries

The beneficiaries of this project were thirty (30) corn farmers who passed the careful evaluation and assessment based on the qualification standards set by the funding agency. Standardized survey questionnaires were conducted by the research technical team to obtain the data on the prevalent corn farming practices of the farmers in the Municipality and the basis to determine the qualified recipient/beneficiaries for this project. The qualified corn farmer beneficiaries were trained under the Farmers’ Field Training Program (FFTP) in consonance to the conceptualized idea of the Farmer-Scientists Training Program (FSTP) of the University of The Philippines-Los Baños, Laguna (UPLB) for 21 Saturdays at the techno-demo site of the Northern Iloilo Polytechnic State College, Batad Campus (Iloilo) for the adoption of this new technology. The technology provides knowledge and skills to smallholder farmers to grow indigenous vegetables (eggplant, squash, sweet potato etc.) side-by-side by the corn known as multiple cropping method.  Eventually, these farmer cooperators became trainers (through training of trainers) for other corn farmers within the municipality. After the long season training, the corn farmer beneficiaries were awarded farm inputs to be used in their farms using the generated technology on farming system/model best suitable to existing climatic conditions in Batad, Iloilo. Proper procedures were strictly followed including validation of farm lots and the signing of the Memorandum of Agreement (MOU) between the farmer beneficiaries and the funding agency. Close monitoring and supervision were done by the research technical team to ensure the implementation of the project.

The on-site and on-farm trials

The techno-demo area situated within a one-hectare agricultural land of the College was utilized as learning site for undergraduate and graduate students specializing in the field of agriculture and for the hands-on training of farmers during their FFTP activities.  In the demo site, farmers were trained to conduct efficacy trials including corn varietal trials, vegetable trials and fertility trials to enhance the best farming practices for the Development of Corn-Based Farming System Model in Response to Climate Change. The weather change scenarios per cropping season were also monitored. The developed technology is the results of the different trials conducted at the techno-demo sites including the fertility trials of different fertilizers (company recommendations and farmers practice) and varietal trials (vegetables and corn varieties). The technology was then adopted by the corn farmers in their own fields (on farm trials).

The study quantified the potential impact of climate change on corn productivity using crop simulation model and the existing weather pattern during the different cropping seasons both in the on-site and in the farm-site trials in Batad, Iloilo. A set of procedures was followed starting with crop efficacy and fertility trials and crop modelling system until the computation of yield statistics (i.e., mean and relative yield changes) to estimate the potential impact of climate change on corn and selected vegetables.  In addition, percentage of corn yield (major crops) and vegetable yields (alternative crops) were computed to determine the extent of climate change impact in the municipality.

Input data

Soil data.  Soil data is an important input data on crop model. Crop model uses information such as soil texture, soil pH, and profile depth to calculate for soil and nutrient balance which also serve as basis for the overall computation of crop growth and development. In this study, soil input data was derived from the latest soil profile and data collected by the Bureau of Soil and Water Management (BSWM) of the Department of Agriculture, Regional Office-6 in the Province of Iloilo on soil profile in the municipal agricultural areas in Northern Iloilo.

Crop data. The corn varieties used in the techno-demo site were inbreed and hybrid corn varieties. The vegetable varieties used in the experimental site include high valued indigenous and hybrid species. The crop parameter for this variety was based from the common practices of the corn growers in the municipality as the result of the survey conducted by the research technical team.

Crop management data.  Crop management information such as planting method and planting density and planting date (cropping season) were based on common practices on corn production system and the common planting window in the municipality for both wet (June to July) and dry (November to December) cropping seasons. Also included are suggested recommendations practices by the Pilipinas Kaneko Seeds Corporation, East-West Seed Company, Inc. and Ramgo International Corporation.

Varietal Selection. There were four Yellow Corn varieties included in the trials namely:  IPB-WQS-1 (OPV), TSG 81 (con Hybrid), P3774 (GMO Hybrid), DK 6919 (GMO Hybrid) and three Green Corn Varieties:  Sweet corn, glutinous corn and glutinous purple in eight treatment combinations replicated two times following Split Plot in a Randomized Complete Block Design (SPRCBD). The trials were conducted at two different locations in Batad, Iloilo: One from NIPSC Techno-Demo Site and the other was at farmer’s field at Sta. Ana, Batad, Iloilo during the wet and dry season to determine the best corn varieties under Batad, Iloilo condition.

Fertility trial on yellow corn (DK 6919 - GMO hybrid) using different fertilizer practices. There were four fertilization practices included in this trial: (1) 90-50-30, (2) 120-30-30, (3) 120-60-90 and (4) 105-35-35 in eight treatment combinations, each replicated two times following the Split Plot in Randomized Complete Block Design (SPRCBD). The purpose of this trial is to determine the yield, shelling recovery, and percentage of moisture content (MC) of the corn included in the varietal selection planted in two different locations.  Fertility trial on yellow corn (DK 6919 - GMO Hybrid) using different fertilizer management options. The other fertilizer management options used in this study were:

  1. Soil Analysis (Control).
  2. 50% Best Farmer’s Fertilizer Practice + 50% Vermicompost.
  3. 25% Best Farmer’s Fertilizer Practice + 75% Vermicompost.
  4. Best Farmer’s Fertilizer Practice.

The general recommendation protocol followed was: Best Farmer’s Fertilizer Practice (120-30-30 NPK), Vermicompost application (3 tons per Hectare), and Soil Analysis (120-20-0). All of the vermicompost fertilizer was applied as basal at planting. 

During 1st side dressing (8-10 DAP), all of the P and K and 50% N were applied, and for the 2nd side dressing (28-30 DAP), the remaining 50% N was used. Eight treatment combinations were replicated three times following Split Plot in Randomized Complete Block Design (SPRCBD).

Yield of yellow corn (DK 6919 - GMO Hybrid) using different tillage practices.  Aside from varietal and fertilization practices of the smallholder farmers, tillage practices has considerable impact to the yield performance of the crops. To determine the influence of tillage practices on crops, experiment was laid out in a Randomized Complete Block Design (RCBD) using three tillage treatments with two replications. The treatments were:  Full Tillage (T1), Minimum Tillage (T2), and Zero Tillage (T3). Soil fertility and Nitrogen uptake are also one of the most important considerations in planting crops. Soil tests have been conducted to determine the soil pH (acidity or alkalinity, not lower than pH 5.5), organic matter content (Nitrogen), Phosphorus (P), and Potassium (K). A balanced level of P and K applied as basal is applied to improve efficiency in nutrient uptake of the planted crops.

Enhancing production of different indigenous vegetables (IVs) grown in a corn-based farm in the marginal upland area of Batad, Iloilo through different fertilizer rate recommendations. This trial aims to formulate location-specific technology for different indigenous vegetables (IVs) and drought-tolerant crops in a corn-based farm and to enhance the utilization and conservation of indigenous vegetables in the marginal upland areas of Batad, Iloilo. The trial was set up in a split-plot randomized complete block design (RCBD) in two replications and had 14 treatment combinations. Data were analyzed using the analysis of variance (ANOVA), and treatment means were compared using Duncan’s Multiple Range Test (DMRT at a 5% significance level. It was conducted simultaneously in two locations, at NIPSC Batad Techno-Demo Research and the Farmer’s Field (Sta. Ana, Batad, Iloilo).  The seven different indigenous vegetables (IVs) used with their corresponding NPK rate recommendations were: Eggplant (170-70-180), Ampalaya (105-35-140), Pole Sitao (134-42-102), Squash (74-28-88), Bottle Gourd (Upo) (105-35-140), Cucumber (127-35-155), and Okra (141-49-49).

DISCUSSION OF RESULT

Evaluating cropping system to enhance sustainable farming. The weather conditions are changing and had already made impacts with production of all food and feed crops.  Corn is no exception and to ensure a future supply we must begin to understand how climate impacts both the phenological development of corn and the productivity. Temperature and precipitation are the two climate factors that will have a major benefit on corn phenology and productivity. The warming climate will accelerate the phenological development because the number of thermal units required for leaf appearance is relatively constant in the vegetative stage. Productivity of corn is reduced when extreme temperature events occur during pollination and is further exaggerated when there are water deficits at pollination. During the grain-filling period, warm temperatures above the upper threshold cause a reduction in yield. It is estimated that for every 1°C increase in temperature, there is nearly a 10% yield reduction (Hatfield and Dold, 2018).  To meet world demand, new adaptation practices are needed to provide water to the growing crop and avoid extreme temperature events during the growing season. Climate change will continue to affect corn production and understanding these effects will help determine where future production areas exist and innovative adaptation practices to benefit yield stability could be utilized.

Focus group discussion (FGD).  The researchers made a courtesy call to the Local Chief Executive of the Municipality of Batad, Iloilo and coordinated with the Barangay Officials of the 14 barangays to conduct the FGD. It was conducted to determine the cropping practices of the corn growers in the marginal areas of the municipality.

The marginal area inhabitants of the 14 barangays participated in the focus group discussion (FGD). The lists of yellow corn growers in the barangays were provided by their respective local executives. Only smallholder corn farmers were included in the list. Smallholders were defined as those planting only 1-3 hectares. A total of 30 corn farmers were selected randomly from the list of smallholders in the 14 barangays. Farmer participants shall meet the following criteria set by the CHED-NAFES, a funding agency to be able to join as farmer participants or beneficiaries of the program. Farmer-beneficiaries need to complete the Farmers Field Training Program (FFTP) to be able to join the project and become recipient of the farm inputs provided by the funding agency. To be able to qualify for this program, farmers shall have: (1) A Certificate of Registration attested by the Municipal Agriculture Officer (MAO) as registered farmers of the municipality; (2) Available area for corn and vegetable production for the replication/adoption of the technologies learned from the FFTP; (3) Committed to learn and undergo the FFTP modular training; and (4) Possessed the ability to become a farmer-trainer and has a willingness to share the information gained with other farmers after finishing the FFTP course. For the selection, the team enlists the help of the community leaders and the municipal agriculture technicians to identify participants.

Farmers in selected barangays also grow crops other than corn, including paddy rice, and some vegetables. Applying a pre-tested questionnaire, enumerators surveyed the randomly chosen corn farmers and asked information on input utilization, varietal use, farming practices, yield, knowledge about hybrid corn, other socio-economic characteristics, and income from corn production, and other farm activities (Table 1). The survey instruments consisted of two components. In the first part, respondents were asked questions about their knowledge, attitudes, and perceptions of biotechnology, GM crops, and food. In the second section of the survey instrument, information about farming practices and the social and economic characteristics of farm households was collected. The information collected includes input utilization, production, expenses, and income from corn production, livestock, and other farm activities.

In the survey areas, 79% of the corn farmers were using the GMO hybrid variety with more than 22 years of experience farming. The GMO hybrid refers to farmers using the DK 6919 and P3774 varieties while 15% used conventional hybrid and 6% used the open pollinated variety (OPV).  This varietal restriction was necessary to make the comparison more meaningful with the difference in outcomes of growing corn in Batad, Iloilo.

Dependent variables include net farm income above cash costs (in pesos per hectare) and household income (income of all farm members, in pesos per month).  Net farm income above cash cost was used as an outcome variable to quantitatively measure the benefits that accrue to farmers from adopting new corn varieties.  Previous studies have shown that using BT maize in the Philippines increased farmers’ income by Php14,849.00 (US$252.21) per hectare (Yorobe & Quicoy, 2006).

Thus, increasing income through the corn technology could substantially relieve poverty, particularly among smallholders. Other outcome variables include the off-farm income of the farmer and the income of all household members. In using the hybrid technology, chemical application commonly performed by the farmer or members of his household is avoided. This opens up opportunities for the household members to engage in other off-farm and non-maize farming activities. Observable covariates include the gender of the household head, household size, human capital embodied in the farmer (years of education, years growing maize, attendance in pest management school).  Type of labor management (proportion of hired labor to total labor) was included as a control covariate due to its influence on the adoption of pest management technologies (Beckmann & Wesseler, 2003; Irawan, Beckmann, Wesseler, 2007).

Seed price and distance to the seed source (in km) are the instrumental variables used for identification of the impact of adoption of the income variables. We propose that these variables are likely to be correlated with the variety of corn adoption but unlikely to be that they influence the income outcome only through their effect on corn adoption technology.   It is plausible that the farther the farm is from the corn seed source, the more likely that they are serviced by the technicians of the seed companies and still have access to the “financiers” in the area who provide input loans. Seed price was also expected to be highly correlated with hybrid corn adoption, as increasing the hybrid seed price would discourage farmers from using the variety.

The summary statistics of the variables used in this study during the pre-survey conducted by the team are given in Table 2. Corn farmers showed higher levels of income than their non-hybrid users. They also appeared to be more educated and experienced in corn farming with more trainings attended. These data confirm the potential for selection bias in estimating the impacts of corn adoption on any type of outcome variable. One reason is that the average prices paid for the corn seed and inputs needed were almost twice that of non- hybrid users and the seed source for the seed is relatively distant from the farm.

Varietal selection

Yellow corn varieties – Selecting the right hybrid variety is an integral part of a successful corn-after-corn production. A corn grower should always ensure to select varieties with proven performance under different environments and stresses (as there may be possible encounter and match planting dates and climatic conditions forecast).

A study was conducted at two different locations in Batad, Iloilo: One from NIPSC Techno-Demo Site and the other was at farmer’s field at Sta. Ana, Batad, Iloilo during the wet and dry season to determine the best corn varieties under Batad, Iloilo condition using four Yellow Corn varieties: IPB-WQS-1 (OPV), TSG- 81 (corn Hybrid), P3774 (GMO Hybrid), DK 6919 (GMO Hybrid) and three Green Corn Varieties:  sweet corn, glutinous corn and glutinous purple in eight treatment combinations replicated two times following Split Plot in a Randomized Complete Block Design (SPRCBD).

Based on the result of the study on the different corn varieties, DK 6919 (GMO hybrid) showed the best corn variety tested in terms of growth and yield performance compared to the other three varieties: IPB-WQS-1 (OPV), TSG-81(corn Hybrid), and P3374YR (GMO Hybrid) at two different areas of establishment during the wet and dry season.

Different locations and interactions between location and corn varieties did not significantly influence the corn agronomic data, while the yield was greatly influenced by different area of establishment. On station (NIPSC, Batad), significantly got higher crop yield of 5,846.81 kg/ha compared to on farm site trial (Brgy. Sta Ana, Batad, Iloilo) with yield of 4,729.11 kg/ha (Figure 2)

The study also indicated that (Table 3) different corn varieties significantly affected all growth and yield parameters. In general, plots using DK 6919 and P3774YR both GMO hybrids significantly got a higher stand count, seedling vigor, plant height and ear height compared to the other two treatments (TSG-81 (hybrid corn) and IPV WQS-1 (OPV).  As to yield, the highest was taken in plots using DK6919 with a yield of 6,230.92 kg/ha, this is comparable in plots using P3774YR with a yield 5,885.39 kg/ha and statistically higher to the last two treatments. Based on the result of the study, DK 6919 showed the best corn variety tested in terms of growth and yield performance.

Wet Cropping Season results showed that corn yield increased as influenced by the packaged of technologies (variety, fertilizer practices and tillage) despite drastic changes in weather conditions conducted under the two cropping seasons. Dry Season Cropping results showed increase in corn yield conducted at two different areas of establishment.  In addition, contrasting change (decrease and increase) in yield was observed during the dry cropping season across scenarios and time periods (Table 4a, 4b, and 4c, respectively). On the average the decrease in corn yield of a particularly variety observed were offset by the increase in corn yield observed in other varieties.'

Green corn varieties

The study was at two locations in Batad, Iloilo: NIPSC Batad Techno-Demo Research Farm and Sta. Ana. Batad, Iloilo. The study aimed to determine the best corn varieties under Batad, Iloilo. The study consisted of two different areas of establishments using three green corn varieties: sweet corn, glutinous corn, and glutinous purple corn, with eight treatment combinations replicated two times following a Split Plot in a Randomized Complete Block Design (SPRCBD).

The experiment (Figure 3) results at two different establishment areas revealed that location and treatment combinations showed no significant difference in the growth and yield performance of different green corn varieties. But concerning different green corn varieties, significant results were observed in yellow corn's development and yield performance. Taller corn plant and ear height were measured using glutinous white corn, while higher initial and final stand count and seedling vigor were assessed using sweet corn and glutinous purple corn. The highest green corn yield was in plots planted with sweet corn varieties, with an output of 10,233.33 kg/ha. The last two treatments succeeded in this. Results implied that sweet corn performed better across locations than other green corn varieties in terms of green corn yield performance.

Fertility trial on yellow corn (DK 6919 - GMO hybrid) using different fertilizer practices

The study was conducted at two different areas of establishment at NIPSC Batad Campus Techno-Demo Research Farm and at the Farmer’s Field (Sta. Ana, Batad, Iloilo). The presence of the three major macronutrients, Nitrogen, Phosphorus and Potassium (NPK) is a major consideration in corn production. The four fertilization practices are the following: (1) 90-50-30, (2) 120-30-30, (3) 120-60-90 and (4) 105-35-35 in eight treatment combinations, each replicated 2 times following the Split Plot in Randomized Complete Block Design (SPRCBD). There are significant differences on the yield, shelling recovery, and percent MC. Based on the Duncan Multiple Range Test (DMRT), the treatments are significantly different from the control (Table 5).

Result of the study showed that location and the interaction between location and different farmer’s fertilization practices did not statistically influence the growth and yield performance of yellow corn (Figure 4). Moreover, different farmers fertilization practices did not influence the growth performance of yellow corn in terms of initial and final stand count, seedling vigor, plant height and ear height.

However, yield in terms of different farmer’s fertilization practices statistically affected the performance of yellow corn. Those treatments using 120-30-30 NPK produced the highest grain yield of 6,272.62 kg/ha which is statistically equal in treatments using 120-60-90 NPK and significantly higher in treatments following 90-50-30 and 105-35-35 NPK level per hectare. The higher yield derived from the first treatment was influenced by a higher Nitrogen level applied in the treatments.  The result indicates that within the two locations, the best farmer’s fertilization practices based on yield performance was derived in treatment practicing 120-30-30 NPK level.

Yield of yellow corn (DK 6919 - GMO Hybrid) using different tillage practices

Tillage is the most important operation on crop production system. The process by which forces are imparted and changes in soil properties occur are known as tillage which is comprised of some technical operations such as ploughing and harrowing.  Tillage practices control weeds, provide a suitable seed bed for crop plants, incorporate crop residues into the soil, make the soil loose, enhance chemical reaction and thereby improves the physicochemical condition of soil which in turn affect the growth and development of crop plants. The preparatory land tillage by different tillage implements have different impact on physical, chemical and biological changes in soil. This is why production of the relevant crop may go up and down Laflen, et. al. (1978) emphasized the importance of tillage in loosening the soil, benefiting chemical reaction, improving moisture condition and structure of the soil.

The experiment was laid out in a Randomized Complete block Design using 3 tillage treatments with two replications.  The treatments were:  Full Tillage (T1), Minimum Tillage (T2), and Zero Tillage (T3). Based on data result (Table 6), ear length was significantly influenced by different tillage practices.  Planting of corn at Minimum Tillage produces more grain yield of 6,748.23 kg/ha compared to full and zero tillage practices.  This result is supported by Muller, et. al. (2002) since soil disturbance is minimal and leaves at least 15-30% of the soil surface covered by crop residue at planting thus leaving the soil undisturbed from harvest to planting except for nutrients attributing to a much higher yield.

Soil fertility and Nitrogen. In corn-after-corn, many farmers are not aware of the value of thorough soil testing and the availability of local nutrient recommendations coming from LGUs and seed companies. Soil tests are needed to measure soil pH (acidity or alkalinity, not lower than pH 5.5), organic matter content (Nitrogen), Phosphorus (P), and Potassium (K).  A balanced level of P and K applied as basal can improve efficiency in nutrient uptake.

Unlike legumes (or beans), corn residues tie up much more nitrogen as they decompose in the soil.  This is why using the same level of N fertilizer in  the succeeding season of corn-after-corn system does not really bring any additional yield; not unless growers increase their N rates by 40kg to 50kg N/ha.

Fertility trial on yellow corn (DK 6919 - GMO Hybrid) using different fertilizer management options

The study introduces fertilizer management options for corn to determine the optimum level of vermicompost and farmer’s best fertilizer practice for yellow corn under Batad, Iloilo condition.  The different fertilizer management options were: (1) Soil Analysis (Control), (2) 50% Best Farmer’s Fertilizer Practice + 50% Vermicompost, (3) 25% Best Farmer’s Fertilizer Practice + 75% Vermicompost, and (4) Best Farmer’s Fertilizer Practice.  The general recommendation protocol followed was: Best Farmer’s Fertilizer Practice (120-30-30 NPK), Vermicompost application (3 Tons per Hectare), and Soil Analysis (120-20-0).  All of the vermicompost fertilizer was applied as basal at planting.  During 1st side dressing (8-10 DAP), all of the P and K and 50% N were applied and for the 2nd side dressing (28-30 DAP) the remaining 50% N was applied. There were eight treatment combinations, each replicated 3 times following Split Plot in Randomized Complete Block Design (SPRCBD).

The study revealed that except for cob length, all parameters were not influenced by different levels of vermicompost and best farmer’s fertilization practice.  However, significant result on yield performance was observed on combined treatments of 25:75% vermicompost and best farmer’s fertilization practice with a higher yield of 5,608.74 kg/ha compared to the 50:50% combination with 5,267.83 kg/ha.

The combination of 75% vermicompost and 25% farmer’s best fertilization practice can be an alternative fertilizer options aside from other fertilizer recommendations. Result showed that the growth and yield parameters were not influenced by cropping season and treatment combinations. But different fertilizer recommendations significantly influenced Plant Height, Ear Height, Final Stand count, Cob Length, Number of rows per cob and number of kernels per row and green yield.

Significantly highest yield was taken in plots using Company recommended fertilizer rates with 14,677.78 kg/ha. This was par from plots using Best farmers fertilizer practice and significantly higher in plots employing Soil analysis and 50:50 Company RR and vermicompost fertilizer combination.

Application of Company recommended fertilizer rates performed best in terms of yield. However, the 25:75 vermicompost fertilizer and Company RR can be an alternative option in fertilizing sweet corn.

Tables 7, 7a and 7b respectively revealed that statistically higher yield was recorded in treatment using 75:25 vermicompost fertilizer and Company with 32,516.67 kg/ha. This was significantly higher than plots applied with Soil analysis and 50:50 vermicompost fertilizer combination and Company RR.

Application of Company recommended fertilizer rates performed better than the rest of treatments, however, the 50:50 Company RR and vermicompost fertilizer combination can be another option in fertilizing eggplant.

The split application of N fertilizer has fulfilled the demand of N since early growth; therefore, the highest of eggplant can be achieved.  It means that reduction 25% Urea and replaces it with stable manure by the same dosage will be able to provide N better than the application of 100% Urea or other fertilizer combinations.  During the early growth, the eggplant gets sufficient N from the Urea, and along with the time passing by, the plant could use N from the matured manure.

Proportion of 75% Urea has fulfilled the demand of N since early growth; therefore, the highest yield of eggplant can be achieved. Eggplant is highly responsive to N fertilizer, and deficient N will inhibit the growth and result low production. The reduced proportion of 25% Urea and replacing it with stable manure could increase efficiency of N absorption because it could reduce the risk of N loss. During the initial growth, the plant has gained sufficient N from Urea due to N has not been available from the stable manure, but when N has been available in stable manure, the eggplant could utilize N from Urea and stable manure. The improvement of soil features as a result of the stable manure application has also increased the efficient N absorption by the plant.  This result conforms to the research by Ullah et al., (2008) that the reduced dosage of inorganic fertilizer and replaced with the organic fertilizer by the same dosage, has resulted higher weight per hectare in comparison with the application of 100% Urea.

Location-specific technology for different indigenous vegetables (IVs) and drought tolerant crops in a corn-based farm.

Indigenous vegetables (IVs) are promising vegetable crops which can resist the adverse effects of climate change and tolerate marginal upland conditions. Hence, these IVs are highly adapted to the surrounding environment as they originated in the region. Most IVs were planted/cultivated hundreds of years ago. These IVs were also called as “forgotten vegetables”, “underutilized”, “undervalued”, and “orphan vegetables” due to the lack of awareness of their importance and contributions to human nutrition. Indigenous vegetables available in the country are important due to their nutritional value and diet supplementation (Capuno, et al.; 2014). These IVs contain sufficient amounts of vitamins and minerals for balanced diets in animal and human consumption. They can supplement food and feed daily requirements for micronutrients.

For instance, the use of IVs such as ampalaya (Momordica charantia) and squash (Cucurbita maxima L.) for human consumption provides the necessary vitamins and minerals required by the human body. These types of vegetables can be grown without the use of agrochemicals particularly synthetic pesticides. Indigenous vegetables are suitable crops for vulnerable marginal uplands brought about by climate change. Marginal uplands are widely distributed in the western part of Batad, Iloilo. It is usually characterized by the growth of grass vegetation like cogon (Imperata cylindrica) which is a good indication of degraded soil. These marginal areas lack soil fertility due to erosion and run-off, and other related human activities which caused problems in the farming of crops, hence large tracts of the marginal uplands are underutilized and unproductive (Pintor et al., 2010). There is a need for rehabilitation of these areas to bring about increasing farm land availability and to enhance food security. One way of increasing productivity here is the planting of indigenous vegetables due to their enhanced resistance to adverse environmental factors such as drought and heavy rain. IVs play an important role as a source of income for some resource-poor households living in marginal upland areas. It also offers malnutrition alleviation and dietary supplementation for these upland landowners (Engle and Altoveros, 2000). The objective of this study is to formulate location specific technology for different indigenous vegetables (IVs) and drought tolerant crops in a corn-based farm and to enhance utilization and conservation of indigenous vegetables in the marginal upland areas of Batad, Iloilo. Through this study, enhancing utilization and conservation of indigenous vegetables will be promoted through technology demonstrations at selected and targeted marginal upland areas in Batad, Iloilo. The outcomes should further encourage the resource poor upland farmers to cultivate further indigenous vegetables in the area.

There were two (2) studies which were conducted simultaneously.  The study sites were in the on-site (NIPSC Batad) and on the farmer’s field (Sta. Ana, Batad).

Enhancing production of different indigenous vegetables (IVs) grown in a corn-based farm in the marginal upland area of Batad, Iloilo through different fertilizer rate recommendations

The trial was set-up in a split-plot randomized complete block design (RCBD) in two replications and had 14 treatment combinations. Data were analyzed using the analysis of variance (ANOVA) and treatment means was compared using the Duncan’s Multiple Range Test (DMRT at 5% level of significance. It was conducted simultaneously in 2 locations, at NIPSC Batad Techno-Demo Research and at the Farmer’s Field (Sta. Ana, Batad, Iloilo).

The seven different indigenous vegetables (IVs) used with their corresponding NPK rate recommendations were: Eggplant (170-70-180), Ampalaya (105-35-140), Pole Sitao (134-42-102), Squash (74-28-88), Bottle Gourd (Upo) (105-35-140), Cucumber (127-35-155), and Okra (141-49-49).

Increasing yield of eggplant (Solanum melongena L.) grown in the marginal upland area of Batad, Iloilo through different fertilizer management options

The study was conducted to increase production of eggplants through different fertilizer management options. The experiment used a randomized complete block design (RCBD) replicated three times. The treatments used were Soil Analysis Recommendation (120-20-0 NPK), Company Recommended Rate (170-70-180 NPK), and 50% Company RR + 50% Vermicompost (based on 3 tons/ha).  All of the vermicompost was applied at planting. Inorganic fertilizers were introduced in split application with the following scheme: first application (Basal application of all vermicompost+P+K+50%N); second application (Side dress at 30 DAP of the one fourth N); and third application (side dress after 2nd priming of the remaining one fourth N).  Other recommended cultural practices for eggplant production were followed to ensure good crop stand. Cost and return analysis were calculated to determine profitability of the kind of fertilizer used. 

The data gathered were analyzed using the analysis of variance (ANOVA) and treatments means was compared using the Duncan’s Multiple Range Test (DMRT) at 5% level of significance (Figure 6).

Result (Figure 6 and Table 8 respectively), in general results showed that the growth and yield parameters were not influenced by cropping season and interactions (treatment combinations). Moreover, different fertilizer recommendations statistically influenced Plant Height, Number of fruits per plant and yield.

Improving agricultural production and productivity by promoting technology adaptation

The Farmers’ Field Training Program approach evolved from the concept of the Farmer-Scientists Training Program that optimal learning is derived from experience and in the case of farmers, from observations in the field. The training integrates the domains of ecology and non-formal education to give farmers the opportunity to learn about their crop, to share experiences and to learn from each other. The training methodology is based upon learning by doing to empower the communities to build their capacity for informed decision-making. It provides a platform to the farming communities where they can share their experiences and knowledge to improve their existing practices through experiential learning processes leading towards sustainable agriculture production.

To introduce the package of technologies (Table 8) derived from NIPSC Batad Techno-Demo Research Farm, two demonstration trials were conducted by the 30 farmer-adopters in their own farms. The 30 farmer-adopters were split in two groups. The first group conducted two demo-trials in their respective farms using: 1) corn + sweet corn technology wherein the best variety (DK 6919), best nutrient management (75% Company RR:25% Vermicompost) and best tillage (minimal) was used for yellow corn with and best nutrient management (75% Company RR:25% Vermicompost) and best tillage (minimal) for sweet corn; and 2) corn alone using the farmer’s conventional practice.  The second group conducted another two demo-trials using: 1) corn + eggplant using the best variety (DK 6919), best nutrient management (75% Company RR:25% Vermicompost) and best tillage (minimal) for yellow corn and best fertilizer management (75% Company RR and 25% Vermicompost) for eggplant and 2) corn alone using the farmer’s conventional practice. The area for corn + yellow corn was 4,500 square meters and 500 square meters respectively and 5,000 square meters for corn alone.  For the corn + eggplant technology, an area of 4,750 m2 and 250 m2 was used respectively. Another 5,000 m2 was used for the corn alone technology.

The need to adapt to the negative impacts of climate change is urgent especially in the agriculture sector. However, there have been no published reports whether marginal corn farmers are applying climate change adaptation strategies. This study sampled 30 marginal corn farmers in Batad, Iloilo to determine the factors affecting their decision to employ adaptations strategies. The adaptation strategies are best variety, best nutrient management and best tillage employed by farmers. Overall, corn farmers are knowledgeable of the impacts of climate change; however, employment of adaptation strategies is minimal. Hence, intervention focused on the package of technologies that would increase probability of farmers employing adaptation strategies. The economic analysis of Corn+ Sweet Corn and Corn Alone data on Table 9, showed that the technology on corn + sweet corn had an average ROI of 119.35 and 65.18 for corn alone. The technology on corn + eggplant revealed an average ROI of 193.67 and 67.01 on corn alone respectively. Assessing performance of sweet corn as compared to pure stand or monoculture is higher in terms of income per unit area of land. Sweet corn was found to be very promising as livelihood for farmers. This is because sweet corn is simpler to grow, labor-saving, less prone to insect pest infestation, and is oftentimes more profitable than growing corn for grain.

Planting sweet corn and eggplant alongside with yellow corn (for grains) with corn with vermicompost as an organic fertilizer and commercial or inorganic fertilizer are some of the types of multiple cropping where farmers will increase their production expanding without their farm area to answer the problem in food shortage in the near future. This conforms to the study of Ambos and Calipusan (2017) that planting sweet corn along with other crops using locally available materials as sources of organic fertilizers such as mushroom spent and rice ash. These materials are found to have essential nutrients that can contribute to the growth and yield of the crops. In addition, using organic matter as source of plant nutrients has contribution to soil condition; it maintains the good soil texture and provides aeration making the soil more suitable for the plant growth and development. Hence, package of technologies that would increase farm income may have positive correlation with increased adoption of climate change adaptation strategies. This can be coupled with capability and capacity enhancement of municipal agricultural officers and extension agents. When farm income increases, then farmers have additional income for possible investment in farm assets. This is expected given that higher value of farm assets of farmers is associated with the likelihood to employ adaptation strategies.

CONCLUSION AND RECOMMENDATIONS

Climatic change will surely affect corn productivity in the Municipality. The extent of the impact depends on the location and cropping season. On the average, the projected climate change will negatively impact corn productivity in the Municipality. In the absence of policy and production adaptation measures the Municipality or even the country as a whole will surely face problem in the supply of corn produce. Different policy and adaptation measure such as Municipal Ordinances to strengthened crop insurance, improvement of irrigation system, dissemination of climate information, breeding of improved varieties, adjustment of cropping calendar, and improvement of current cropping system can reduce if not totally eliminate the negative impact of climate change on corn productivity in the Municipality.

This study also proved the yield effectiveness of growing Corn-vegetable farming method at a minimum tillage using 25-75 fertilizer recommendation a developed technology on how to carry out climate change impact on corn. This technology can also be applied for other crops such as eggplant that proven to be effective to be planted along with corn in a more diversified method of farming.

On the other hand, it is highly recommended to explore and assess the impact of rainfall, occurrence of pests and diseases, as well as changing land suitability brought about by changing climate. Furthermore, adding economic facet (i.e., prices, market demand, etc.) on the analysis to economic can provide a more robust quantification on impact of climate change on the corn production system in the Municipality of Batad.

REFERENCES

Ambos, A. L., & Calipusan, B. C. (2017). GROWTH AND YIELD PERORMANCE OF SWEET CORN (Zea mays L.) INTERCROPPED WITH SWEET POTATO (Ipomoea batatas L.) APPLIED WITH MUSHROOM SPENT AND RICE ASH. Science International, 29(2), 87-87.

Beckmann, V., & Wesseler, J. (2003). How labour organization may affect technology adoption: an analytical framework analysing the case of integrated pest management. Environment and Development Economics, 8(3), 437-450.

Capuno, O. B., Gonzaga, Z. C., Dimabuyu, H. B., & Rom, J. C. (2014, August). Indigenous vegetables for coping with climate change and food security. In XXIX International Horticultural Congress on Horticulture: Sustaining Lives, Livelihoods and Landscapes (IHC2014): 1102 (pp. 171-178).

Data on Corn Production, Office of the Municipal Agriculture, Batad, Iloilo, Philippines (2016).

Engle, L. M., & Altoveros, N. C. (1999, August). Collection, conservation and utilization of indigenous vegetables. In Proceedings of a Workshop AVRDC, Shanhua, Tainan, Taiwan (pp. 16-18).

Hatfield, J. L., & Dold, C. (2018). Climate change impacts on corn phenology and productivity. Corn: Production and human health in changing climate, 95.

Irawan, E., Beckmann, V., Wesseler, J., & Irawan, E. (2007). A comparative analysis of farm labor organization and IPM adoption: An empirical study of fruit tree farming in Thailand. Asia RECREATE international seminar “Sustaining growth.

Laflen, J. M., Baker, J. L., Hartwig, R. O., Buchele, W. F., & Johnson, H. P. (1978). Soil and water loss from conservation tillage systems. Transactions of the ASAE, 21(5), 881-0885.

Moch, Dawan Maghfoer, Roedy Soelistyono and Ninuk Herling. Growth and Yield of Eggplant (Solanum melongena L.) on Various Combinations of N-Source and Number of Main Branch. AGRIVITA VOLUME 36 No. 3 OCTOBER ± ISSN: 0126-0537. Accessed October 21, 2020.

Müller, A. K., Westergaard, K., Christensen, S., & Sørensen, S. J. (2002). The diversity and function of soil microbial communities exposed to different disturbances. Microbial ecology, 44(1), 49-58.

Pintor, L.L., Austria, M.V., Tanudtanud, J.B., and Castillo, E.T. (2010). A Research Compendium for Damaged Marginal Uplands. (Laguna, The Philippines: Ecosystems Research and Development Bureau Department of Environment and Natural Resources College)

Ullah, M. S., Islam, M. S., Islam, M. A., & Haque, T. (2008). Effects of organic manures and chemical fertilizers on the yield of brinjal and soil properties. Journal of the Bangladesh Agricultural University, 6(2), 271-276.

Sutanto, R. (2002). Towards organic farming as alternative and sustainable agriculture. Kanisius. Yogyakarta. p 218.

Suwandi. (2009). Measuring of plant nutrient needs in development of innovation sustainable vegetable cultivation. (in Indonesian). Development of Agricultural Innovation. 2 (2): 133-147.

Yorobe, J. M., & Quicoy, C. B. (2006). Economic impact of Bt corn in the Philippines. Philippine Agricultural Scientist, 89(3), 258.

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