KORELASI INDEKS KUALITAS TANAH DAN KUALITAS PAKAN TANAMAN JAGUNG PADA TOPOGRAFI BERBEDA = CORRELATION BETWEEN SOIL QUALITY INDEX AND CORN PLANT FEED QUALITY IN DIFFERENT TOPOGRAPHIC

HENRI. Correlation between soil quality index and corn feed quality under different topographic (supervised by Asmita Ahmad and Renny Fatmiyah Utami). Background. Corn (Zea mays) is a critical commodity for feed, food, and bioenergy; however, national production has been declining, posing a threat to feedstock availability. Variations in land conditions and topography are believed to significantly influence corn yield and feed quality in South Sulawesi. Objective. This study aims to examine the correlation between the Soil Quality Index and corn feed quality in highland and lowland areas, and to identify the soil elements and indicators that most significantly contribute to seed nutritional quality, thereby providing a foundation for enhancing soil management and feed formulation. Method. The research was conducted in two distinct topographical areas: the highlands of Bantaeng Regency (approximately 717 meters above sea level) and the lowlands of Jeneponto Regency (approximately 20 meters above sea level). Soil quality was evaluated using the Soil Quality Index (SQI), based on 10 Minimum Data Set (MDS) indicators encompassing physical, chemical, and biological soil properties, weighted through Principal Component Analysis (PCA), and calculated as the Comprehensive SQI before and after cultivation. Feed quality was assessed through proximate analysis, and the physical quality of corn kernels was evaluated according to SNI 01-4483-1998. The relationship between soil characteristics and feed quality was analyzed using Pearson's correlation coefficient. Results. The SQI value increased in Bantaeng from 0.634 (good) to 0.909 (very good) and in Jeneponto from 0.192 (very low) to 0.688 (good), indicating an enhancement in soil function with the implementation of cultivation practices (crop rotation and balanced fertilization), which can improve the physical, chemical, and biological properties of the soil. Proximate analysis revealed that the moisture content (<14%), crude protein (8.6-9.9%), and fat content (9.2-9.8%) met SNI standards, while crude fiber (5.1- 5.2%) and ash (2.1-2.6%) slightly exceeded the maximum limits. Correlation tests indicate that the availability of P₂O₅ and K⁺ is strongly related to fat content and ash content in the highlands, while soil nitrogen is strongly negatively correlated with crude protein in both locations at a 1% significance level. Conclusions. Bantaeng exhibits superior soil quality with high carrying capacity but produces seeds relatively high in fiber and ash for feed, whereas Jeneponto is more responsive and dynamic, with higher protein and fat content, but requires enhancement in organic carbon and phosphate. Implications. Site-specific soil management based on topography and nutrient dynamics is essential to improve the quality of corn feed. Fertilization and soil conservation strategies should be directed toward integrated soil quality improvement to support sustainable corn production and meet the needs of the feed industry.