Soil quality assessment for sustainable cultivation of Opuntia ficus-indica in Kutch (India): identifying key edaphic factors

Abstract

Soil quality plays a fundamental role in determining crop productivity, particularly in arid and semi-arid regions where soil fertility constraints and salinity pose significant challenges. Opuntia ficus-indica (cactus pear) is a drought-resilient crop with considerable potential for sustainable agriculture, yet limited research has focused on the specific soil properties influencing its growth and biomass production. This study aimed to evaluate the relationship between soil quality parameters and Opuntia ficus-indica growth performance in Bhuj, Kutch, an arid region with alkaline and nutrient-limited soils. Soil and plant samples were collected from eight farms, ensuring uniform sowing conditions. Five composite soil samples (0-30 cm depth) and five plant samples were collected per farm, and nine soil parameters (pH, electrical conductivity, soil organic carbon, nitrogen, phosphorus, potassium, calcium, magnesium, sulfur, and soil texture) were analyzed using standard laboratory methods. Plant growth metrics, including cladode number, cladode weight, and cladode length, were recorded. The results revealed that calcium (r=0.901, p<0.001), nitrogen (r=0.844, p<0.001), and potassium (r=0.918, p<0.001) were the most critical soil properties positively influencing plant growth, while high soil pH (r=-0.829, p<0.001) and electrical conductivity (r=-0.802, p<0.001) negatively impacted plant performance. Principal component analysis (PCA) identified soil fertility (Ca, N, K) and salinity (EC) as the most influential factors, explaining 79.3% of the total variance. Regression analysis further confirmed that soil fertility parameters significantly contributed to biomass accumulation (R2=0.78, p<0.001).