Effect of Deficit Irrigation at Different Growth Periods on Yield and Quality of Sugarcane (Saccharum officinarum l.) First Ratoon

Aims: This study aimed to evaluate the effect of deficit irrigation at different growth periods on the yield and quality of sugarcane (Saccharum spp.) first ratoon. Study Design: The study was carried out in Randomized Complete Block Design (RCBD), with three replications. Place and Duration of Study: A field experiment was conducted during two seasons, 2020-21 and 2021-22 at Guneid Sugarcane Research Center Farm, Sudan. Methodology: Irrigation deficit treatments were applied when available soil moisture content (ASMC) reached 25% in the root zone at eight different growth periods viz; DT1: first day to day 50th, DT2: day (5th - 100th), DT3:  day (10th -150th), DT4: day (15th - 200th), DT5: day (20th - 250th), DT6: day (25th - 300th), DT7: day (30th - 350th) and DT8:  day 35th to day 400th after ratoon establishment. These were compared with optimum irrigation (DT0) which was irrigated at 60% ASMC at the root zone. Results: The results showed that all deficit irrigation treatments (DT1 to DT8) recorded significant cane and sugar yield reduction to the control (DT0) in the two growing seasons. In this sense, DT3, DT4 and DT5 treatments have recorded the highest cane and sugar yield reduction. Moreover, irrigation deficit affected negatively the sugarcane ratoon yield parameters with low cane water productivity in DT4 and DT5 treatments. Therefore, sugarcane first ratoon must be avoided to deficit irrigation at age of 3.3 months to 10.0 months. Conclusion: According to the results sugarcane first ratoon (Variety Co 6806) established in December under the Central Sudan Agro-climatic zone (Gunied conditions) must be avoided to deficit irrigation at ratoon age of 3.3th month to age 10.0th month (at ratoon age 100 days to 300 days), because of high reduction on cane yield and sugar yield and low in water productivity.