No abstract

The present study was conducted at Shandaweel Agricultural Research Station (26.5013° N, 31.7651° E), Sohag Governorate , Egypt in 2015/2016 and 2016/2017 seasons to deternine optimize irrigation interval and seed rate of sugarcane production. The current study included eighteen treatments representing the combinations among two sugarcane varieties (Giza-Taiwan 54-9 and G. 2003-47), three irrigation intervals (10, 15 and 20 days) and three seed rates of (25200, 37800 and 50400 buds/fed) resulted from one, one and half and two rows of seed setts . /furrow which contain three buds for each, respectively. The treatments were allocated in a Randomized Complete Block Design using a split-split plot arrangement with three replications. The results showed that decreasing irrigation intervals from 20 to 15 days significantly increased stalk length, stalk diameter, number of millable canes/fed, cane and sugar yields/fed in both seasons. However, brix, sucrose and sugar recovery percentages were negatively and significantly affected by increasing the period between irrigations. Varieties differed significantly in their response to all the studied characters. The commercial variety G.T.54-9 recorded higher values of stalk length, stalk diameter and cane yield/fed, while the promising variety G. 2003-47 had higher number of millable canes/fed, brix, sucrose and sugar recovery percentages as well as sugar yield, in both seasons. Planting sugarcane using two rows of seed setts/furrow attained significant increases in stalk length and the number of millable canes/fed, in both seasons, while thickest stalks were obtained by 1.0 drill of cane cuttings. The higher brix, sucrose and sugar recovery percentages, cane and sugar yields were obtained by 1.5 drills of cane cuttings in both seasons. Under conditions of the present investigation, planting any of the evaluated cane varieties using 1.5 and/or 2.0 drills of cane setts and irrigating them at 10 and/or 15-day intervals can be recommended to get the maximum cane yield/fed. However, planting sugarcane variety G. 2003-47 using 1.5 drills of cane cuttings and irrigating it every 15 days can be recommended to obtain the highest sugar yield/fed.