Efficient Water Management in Sugarcane with Composted Coir Pith and Sugarcane Trash Under Tropical Indian Conditions

A field experiment on water management with composted coir pith and sugarcane trash under two irrigation levels (100 and 75% of recommended level of irrigation) with the aim of assessing performance of bud chip settling in 150 × 45 and 150 × 60 cm spacing was conducted in split-plot design at ICAR-Sugarcane Breeding Institute, Coimbatore, Tamil Nadu, India, during 2013–2014, 2014–2015 and 2015–2016. The soil of the experimental site was sandy clay in texture, taxonomically classified as typic haplustalf, low in organic carbon, medium in available N and available P and fairly high in K, slightly alkaline in reaction with normal electrical conductivity. The prevailing climatic condition during experimentations represented tropical Indian conditions, wherein mean temperature ranged in between 21.24 and 33.10 °C with a mean relative humidity of 54.58–85.5%. As against the normal rainfall of 674.2 mm, only 356, 537 and 679 mm of rainfall was received during 2013–2014, 2014–2015 and 2015–2016 crop seasons indicating the erratic behaviour of rainfall. The results revealed that application of 10 t/ha composted coir pith or 5 t/ha of sugarcane trash in furrow at the time of planting and scheduling irrigation in sugarcane at 75% of recommended level of irrigation saved 387, 344 and 255 mm irrigation water; in addition, it gave higher irrigation water use efficiency (0.82 t/ha/cm), net returns (99,039 Rs/ha) and benefit–cost ratio (1.79) over scheduling irrigation at 100% level. Further it was also observed that setts planting at 90 cm recorded 15.47 and 25% higher cane yield than bud chip settling planting at 150 × 45 and 150 × 60 cm, respectively. Amongst two soil moisture conservation measures, i.e. composted coir pith and trash, application tried in sugarcane conserved soil moisture efficiently and recorded higher soil moisture by 8.10 and 7.62% and cane yield 19.59 and 12.91%, respectively, over the control. Planting bud chip settling at 150 × 45 cm spacing was found superior over bud chip settling planting at 150 × 60 cm spacing. Hence for efficient water management in sugarcane under tropical Indian condition, use of composted coir pith @ 10 or 5 t/ha of chopped trash with 75% of recommended level of irrigation in bud chip settling (150 × 45 cm) planting is recommended.