Influence of Acidic Soils on Growth and Nutrient Uptake of Cocoa (Theobroma Cacao L.) Varieties

Growth and Nutritional Responses of Juvenile Wild and Domesticated Cacao Genotypes to Soil Acidity

“…Domination of Al 3+ or H + may directly affect crop tolerance to acid soils [17]. Acidity can diminish growth, root elongation, and biomass production, as observed in our study and others, in cacao and other tropical crops [6,12,15,30,31]. One of the main effects of Al 3+ in plants is the inhibition of root elongation, resulting in stubby root tips, making plants more susceptible to drought, or limiting nutrient acquisition [32].…”

“…One of the main effects of Al 3+ in plants is the inhibition of root elongation, resulting in stubby root tips, making plants more susceptible to drought, or limiting nutrient acquisition [32]. Some of the reported effects of acidity (mainly aluminum), as well as other previous studies in cacao, are decreased shoot and root dry weight, reduced stem height, root length and root volume [12][13][14][15]. Nevertheless, the present results on height and diameter were like those reported by Dogbatse et al [15], who observed no significant differences in height and diameter in different soils that had pH values ranging from 4.21 to 5.64.…”

“…Our results indicate that liming acid soil improves macro nutrient acquisition by cacao and liming reduces micronutrient absorption, especially Mn, which was observed in toxic concentrations (>500 mg kg −1 ) as stated by Marschner [34]. Several studies in cacao focused on concentrations and uptake of macronutrients (N, P, K, Ca, Mg, and S) in acidic and non-acidic soils and showed that plants with less Al 3+ , have a higher uptake of N, P, K, Ca, Mg, and S [12,13,15,31,35]. In the case of micronutrient uptake, they are less studied in cacao.…”

“…Acidification has many sources and one of the most important ones is the replacement of exchangeable Ca 2+ , Mg 2+ , and K + by H + and Al +3 , consequently, metal toxicity (Al and Mn primarily) and nutrient deficiencies (i.e., P) occur in acid soils that limit plant survival and productivity [7,17]. In general, P has been one of the most studied nutrients in acid soils due to its general deficiency; its deficiency is related to metabolic, physiological, and productivity-limiting problems in different crops, and cacao is no exception [15,17,29]. Our results indicate that liming acid soil improves macro nutrient acquisition by cacao and liming reduces micronutrient absorption, especially Mn, which was observed in toxic concentrations (>500 mg kg −1 ) as stated by Marschner [34].…”

“…Cacao genotypes are known to differ widely in their tolerance to soil acidity and Al [12][13][14][15][16]. Genotypes with a high nutrient uptake efficiency under soil acidity stress may have an advantage in adapting to mineral-stressed soil ecosystems of the cacao growing regions.…”