Optimizing Soil Moisture, Mulching, and Spacing for Yield and Water Productivity in Irrigated Elephant Foot Yam (Amorphophallus paeoniifolius)

Aims: To standardize crop spacing and irrigation requirements under different mulching situation for better yield and water productivity.

Study Design: The experiment was designed in RBD with two replications.

Place and Duration of Study: The experiment was conducted at Agronomic Research Station, Kerala Agriculture University (KAU), Chalakudy for three consecutive years from 2016 -17, 2017 – 18 and 2018 – 2019.

Methodology: Study conducted with 18 treatments, includes three levels of irrigation, three types of mulching and with two different crop spacing. Observations on weed count and weed dry matter production were also taken to study the effect of different mulches on weed growth. Biometric observations of crop growth and yield were recorded.

Results: Observations on biometric characters revealed that both the height and diameter of the crop canopy were significantly influenced by mulching and found to be highest in the plot where leaf was used as the mulching material and the yield of Amorphophallus during 2016 - 2017 showed that corm weight was greatly influenced by irrigation levels, mulching and spacing. Corm yield was lowest in the plot where irrigation frequency was once in three days (21.02 t/ha). Yield in leaf mulched plot was 38.11 t/ha while in plastic mulched and no mulched plots were 23.50 and 19.50 t/ha. Effect of treatments on water productivity and BC ratio showed that leaf mulching of the crop has significant effect. In leaf mulched plot, water productivity in 2016-17 was 2.03 while it was only 1.854 and 0.886 in 2017-18 and 2018-19. Similarly, BC ratio was highest for leaf mulched plot followed by no mulch and plastic mulch plot.

Conclusion: The experimental results from 2016 -17, 2017 – 18 and 2018 – 2019, showed that Amorphophallus planted at a spacing of 90 cm x 90 cm, irrigated at a frequency of once in three days along with leaf mulching can increase the yield and water productivity along with effective control of weed population.