Carbon-Sequestering Fertilizers Usage to Boost Potassium Efficiency in Wheat Growth Under Saline Conditions

Abstract

Potassium (K) is a crucial element required for the healthy growth of plants, as it activates many enzymatic reactions in the plant body. Nowadays, K-deficiency is widespread worldwide. The high cost of potassium fertilization and less awareness about the pros of external nutrition from K fertilizer application are possible reasons for K-deficient soils in Pakistan. Efforts are ongoing to improve the potassium use efficiency (KUE) and bioavailability of K from commercial potassium sources. Therefore, a field experiment commenced to minimize the bioavailable K losses using carbon sequestering fertilizer (CSF) under saline soil conditions (4 dS m -1 ) using wheat as a test crop in Pind Dadan Khan, Punjab, Pakistan. The experiment ran in a three-replication randomized complete block design (RCBD) statistical scheme using four treatments, i.e., T1 = Control; T2 = Filter cake press mud (FCP) as CSF; T3 = Sulphate of potash (SOP); and T4 = SOP + FCP, using two wheat varieties, namely, Faisalabad 2008 (FSD-08) and Chakwal-50. Results implied that SOP application in combination with FCP (T4) performed best treatments with Faisalabad 2008 as the better variety than Chakwal-50 under saline growth environment. Maximum spike length (8.85 cm), the number of grains/spike (45), shoot dry weight (2.75 g), soil K contents (310 ppm), soil C content (1.03%), chlorophyll content (2.18 µmol m -2 ), and H-ATPs (99.5) resulted in Faisalabad 2008 when applied with the combination of SOP and FCP (T4). Thus, the combined application of mineral and organic sources of CSF improved the wheat growth parameters and nutritional status of the soil.