Site and soil description:
An experiment was conducted at Regional Agricultural Research Station (RARS), Jamalpur during 2017-2018 to increase the soil moisture retention and to increase yield of chilli using different mulch. Nutrient status of initial soil prior to fertilization, initial soil temperature (°C) & soil moisture (%) and weather data, 2017-2018 are presented.
Fertilizer and treatments:
The experiment was conducted during the period of November 2017 to April 2018. The soil was neutral in pH and silty loam in texture. Before mulching, moisture content in rice straw and water hyacinth were estimated and it was 7.4% and 9.1%, respectively. The land was prepared by tilling in two directions with a power tiller. Weeds and crop stubble were removed. Plots were 3m × 2m on 15 cm high raised beds. Urea, triple superphosphate (TSP) and muriate of potash (MP) were applied (260, 200 and 150 kg ha-1, respectively). Total amount of TSP, MP and half of urea were broadcast and incorporated to the soil at final land preparation. The rest of urea was top-dressed at 40 days after transplanting (DAT). Well decomposed cowdung was applied (5 t ha-1) prior to final tilling. BARI morich 1 was used as test variety transplanted in plots in Randomized Complete Block Design (RCBD) with three replications. The row and plant spacing was maintained at 60 cm and 50 cm respectively and each plot accommodated 20 plants.
Treatments were as follows as
T1 = no mulch
T2 = rice straw mulch @ 5t ha-1
T3 = water hyacinth mulch @ 5t ha-1
T4 = black polyethylene mulch
T5 = White polyethylene mulch
Mulching material
(i) Plastic mulching-After taking the required length of film for crop, (3 × 2 m2 plot-1) one end of the mulch film was anchored in the soil approximately 4-6 inch and then film was unrolled along the length and width of the plot. A sharp tin on a handle was used to easily cut a hole on tightly laid mulched at 50 cm spacing and then transplanting done.
(ii) Organic mulching-before lying of rice straw and water hyacinth, transplanting distance of 50 cm was marked. After marking, seedlings were transplanted and simultaneously organic mulches spread.
Transplant establishment:
Thirty-day old seedlings were transplanted at 60 cm × 50 cm spacing on 29 November 2017. Seedlings were watered after transplanting. Guard rows were established around the entire plot. Gap filling of seedling was with healthy seedlings previously planted in the border area. The fungicides of carbendajim group (Autostin at 2 g/1L) and insecticide of Imidachloprid (Imitaf @ 0.25 ml/L) were applied to prevent insect and disease infestation.
Soil temperature:
Soil temperature was determined by soil thermometer at 5 cm and 10 cm depth in the experimental field. In every one month, it was determined in three different times (7 am, 12 pm and 5 pm) of the day.
Soil Moisture:
Soil moisture content was determined by soil moisture meter at 5 cm and 10 cm depth in every fifteen days. It was also determined by gravimetrically. (Taking fresh soil sampled from depths of 0–10 cm in the experimental field every two weeks. Sampled fresh weight was weighed and dried in oven for 24 hours at 105°C. The gravimetric soil water content was determined using following formula after weighing oven dried soil sample). Soil moisture content (%) = fresh soil weight − dry soil weight /dry soil weight × 100.
Harvest:
Green fruit were harvested at weekly intervals when fruit length was at least 6.5 cm. Harvesting was started on 2 March 2018 and continued till 25 April 2018.
Data collected:
Data on growth parameters were recorded and analyzed statistically using statistical software STAR which was developed by IRRI.