COMBINING ABILITY OF FORAGE YIELD FOR SORGHUM-SUDANGRASS HYBRIDS UNDER WATER STRESS USING LINE X TESTER

摘要

Sorghum is one of the essential fodder crops in Egypt and its demand is increasing day by day due to increasing the number of cattle farm. While, water deficit is one of the main reasons for crop reduction worldwide including Egypt. Therefore to meet the shortage of fodder, it is very essential to develop high yielding hybrid or sorghum cultivars which are suitable to grow under water stress condition. The present investigation was conducted at Sakha Agri- culture Research station famr, Egypt during two growing seasons. In 2016 twelve hires and four test- ers of sorghum species were crossed according to line x tester design to produce 48 crosses. The 48 crosses, their parents and two checks (‘hybrid 102’ and ‘hybrid SX17’) were evaluated during 2017 summer season at the two locations Sakha and Sids Agricultural Research Stations. Tlnee adjacent ex- periments were canied out according to three irriga- tion interval periods viz., 14, 21, 28 days intervals at each location using randomized complete block de- sign with three replicates. The results of the present study indicated that the mean squares for total fresh and dry forage yield plant" were varied significantly under the three irrigation intervals at the two loca- tions and combined over both locations and the tluee irrigation intervals). In addition, mean square values for interaction of irrigation intervals, locations, and irrigation x locations were found to be highly signif- icant. The tester parent (‘Gizal’) had the highest mean performance for fresh and forage yield plant" at Sakha location, while, the highest values were provided by line parent L12 (‘ICS693’). More- over, the cross 45 (L12 x T1 :. was superior and had the highest mean performance for fresh and dry forage yield plant“ under normal and water deficit condi-Sorghum is one of the essential fodder crops in Egypt and its demand is increasing day by day due to increasing the number of cattle farm. While, water deficit is one of the main reasons for crop reduction worldwide including Egypt. Therefore to meet the shortage of fodder, it is very essential to develop high yielding hybrid or sorghum cultivars which are suitable to grow under water stress condition. The present investigation was conducted at Sakha Agri- culture Research station famr, Egypt during two growing seasons. In 2016 twelve hires and four test- ers of sorghum species were crossed according to line x tester design to produce 48 crosses. The 48 crosses, their parents and two checks (‘hybrid 102’ and ‘hybrid SX17’) were evaluated during 2017 summer season at the two locations Sakha and Sids Agricultural Research Stations. Tlnee adjacent ex- periments were canied out according to three irriga- tion interval periods viz., 14, 21, 28 days intervals at each location using randomized complete block de- sign with three replicates. The results of the present study indicated that the mean squares for total fresh and dry forage yield plant" were varied significantly under the three irrigation intervals at the two loca- tions and combined over both locations and the tluee irrigation intervals). In addition, mean square values for interaction of irrigation intervals, locations, and irrigation x locations were found to be highly signif- icant. The tester parent (‘Gizal’) had the highest mean performance for fresh and forage yield plant" at Sakha location, while, the highest values were provided by line parent L12 (‘ICS693’). More- over, the cross 45 (L12 x T1 :. was superior and had the highest mean performance for fresh and dry forage yield plant“ under normal and water deficit condi-ble scope of improvement in forages. The best gen- eral and specific combiners could be used as piime maten'a1s for selection in breeding program to im- prove fodder yield components under water deficit conditions.