Soil moisture based deficit irrigation management for sugarcane (Saccharum officinarum L.) in semiarid environment

Sugarcane is a high biomass crop which requires large amounts of water. In a semiarid environment deficit irrigation is inevitable to produce acceptable yields. The field experiments were conducted for two seasons (2015 and 2016) on Sugarcane (Saccharum officinarum L.)by applying water deficit in three regimes (0%, 30% and 60% water deficit) during three phenological stage (tillering, grand growth and maturity) such that the effect of a specified water deficit during a specified phenological stage can be investigated separately. The experiment formed 27 irrigation schedules replicated twice in Randomized Block Design. The irrigations were provided based on water deficit underlined in each irrigation schedule during different phenological stages on the basis of actual soil moisture in root zone. The demonstrated data indicated that the net increase in growth characters with net water used within a phenological stage was to great extent affected by the grand growth stage. The yield contributing characters and cane yield reduced with increase in water deficit imposed mainly in grand growth followed by tillering stage. A water deficit imposed in maturity stage only marginal affected the yield. The highest yield of sugarcane obtained underwater deficit free schedule (181.5 tha−1); 30% and 60% water deficit throughout season noticed with significantly lower cane yield as 157.1 and 107.4 tha−1, respectively. The relative cane yield reduction over water deficit free schedule registered between 0.7% and 40.6% with relative decrease in the water use by 2.5–33.4%. A deficit irrigation strategy with 0% water deficit at tillering, 30% at grand growth and 60% at maturity stage was found appropriate as it represents the non-significant reduction in yield over water deficit free condition, beside it leads to a 13.3% lesser water use. Based on soil moisture, the total water use of sugarcane underwater deficit free and best deficit conditions were estimated as 1339 and 1160 mm respectively. The study recommends to practice appropriate irrigation scheduling under water shortage situation for maximizing water use by providing irrigations as per requirement, applying less water than required, such that the overall productions are optimized. •The semi-arid tracts of many countries have limited water availability and it is necessary to use the available water resources efficiently for different crops; and especially for sugarcane that consumes major portion of available irrigati