Trickle and micro sprinkler fertigation on soil microbial population in cocoa (Theobroma cacao L.)

Cocoa, the ‘Food of Gods’ is one of the important plantation crops consumed worldwide and around 40 - 50 million people depend on cocoa for their livelihood. An experiment was conducted during 2010 and 2011 to investigate the impact of N, P and K fertilizers through fertigation on soil microbial population of cocoa at Tamil Nadu Agricultural University, India. The study was laid out in randomized block design with 13 treatment combinations. The study shows that, fertigation with 125% recommended fertilizer dose as water soluble fertilizer through fertigation by micro sprinkler irrigation (T10) had the highest soil bacterial population (60.10 × 10-6 CFU g-1), fungal population (16.61× 10-4 CFU g-1) and actinomycetes population (8.07 × 10-3 CFU g-1). The same treatment recorded higher yield characters viz., beans per pod (47.81), bean length (2.47 cm), bean girth (3.57 cm), single bean wet weight (3.15 g), single bean dry weight (1.31 g), dry bean weight per pod (62.23 g), dry bean yield per tree (3273.63 g).