Effect of mulch types on soil moisture, soil fertility, growth and yield of pineapple (Ananas comosus) in hill zone of Assam

A field experiment was carried out in Hill Zone of Assam from 2017 to 2019 with the objective of identifying mulch types on soil moisture retention, soil physical and chemical properties, growth and yield of pineapple (Ananas comosus) grown in hill slopes under farmers’ field condition. The treatments consisting of mulching with black polythene, dhaincha (Sesbania aquleata) as mulch, frequent slashing of weeds, soil mulching (soil mounding) and farmers practice without any mulch as control were evaluated in a randomized block design. Soil moisture content at 0-30cm depth was significantly different among the mulching methods and highest value of 14.2% at 0-30cm depth at harvesting was recorded in black polythene followed by slashing of weeds (13.1) and minimum in farmers practice. Soil texture was not affected by various mulches but there was a decline in bulk density with mulching and minimum value of 1.23 kg m-3 was recorded under slashing of weeds. Higher organic carbon (8.8 g kg-1), available nitrogen (341.8 kg ha-1), phosphorus (9.5 kg ha-1) and potassium (100.6 kg ha-1) were recorded in organic mulches i.e. slashing of weeds and dhaincha. The highest yield attributing characters and fruit yield of 38.3t ha-1 was recorded in the black polythene treatment followed by dhaincha as mulch (36.5 t ha-1) and frequent slashing of weed (35.6 t ha-1). Soil mulching and farmers practice recorded significantly lower yield than other treatments.