Registration of ‘Alkabo’ Durum Wheat

’Alkabo’ (Reg. No. CV-1008, PI 642020), spring durum wheat (Triticum turgidum L. var. durum Desf.) was developed by the North Dakota Agricultural Experiment Station in cooperation with the USDA-ARS and released on 1 June 2005. Alkabo is the name of a former community in northwestern Divide County in western North Dakota. The Alkabo name comes from the alkali-gumbo soil common to the area. Alkabo was released on the basis of its high grain yield, test weight, and quality. Alkabo was tested as the experimental line D96604 and was selected from the cross D901247/D89263 made in 1992. The parent D901247 was derived from the cross D81154/‘Renville’ (PI 510696)/LDN(Dic-5B). The pedigree of D81154 is PI19571/ ‘Ward’(CI 15892). LDN(Dic-5B) is a substitution line of ‘Langdon’ (CI 13165) with chromosome 5B of Triticum dicoccoides accession FA-15-3 (Joppa and Cantrell, 1990). D89263 was derived from the cross ‘Fjord’/D8194. D8194 was derived from the cross D7690/‘Vic’ (CI 17789). The pedigree of D7690 is D68111/‘Rugby’ (CI 17284)//‘Crosby’ (CI 17282). D68111 was derived from the cross D65150/‘Leeds’ (CI 13768). The cross of D65150 is Pi/ TM//2*Tc/3ZB/’Wells’ (CI 1333). Alkabo was developed using the pedigree breeding method and was bulked in the F5 generation as an F4–derived line in 1996. Six thousand F4:13 heads were selected from quality drill strips at Langdon, ND, for seed purifi cation. Heads were threshed individually and seeded as headrows at Yuma, AZ, in 2004. Nonuniform rows were discarded, and the remaining rows were bulk harvested as Breeder seed. Alkabo is a daylength-sensitive durum wheat that is similar in heading date (64 d from seeding to when approximately 50% of the plants had heads completely emerged from the boot) to ‘Pierce’ (Elias et al., 2004) and 1 d earlier than ‘Mountrail’ (Elias and Miller, 2000b). Alkabo has an average plant height of 85 cm, which is 5 cm shorter than Ben (Elias and Miller, 1998) and 12 cm taller than the semidwarf cultivar Plaza (Elias et al., 2001b). The culm of Alkabo is white, and the peduncle is erect. Alkabo has midlong spikes that are awned, oblong, lax, and erect. The awns are white and 14 to 15 cm long. The glumes are oblique, white, long, and wide. The kernels are amber, hard, long, and elliptical; the germ is large; the crease is midwide and shallow, and the brush is medium. Based on 49 location years of testing in the Uniform Regional Durum Nursery (URDN) from 2000 to 2004, the mean grain yield of Alkabo (3951 kg ha−1) was higher than Ben (3729 kg ha−1), ‘Maier’ (3689 kg ha−1) (Elias and Miller, 2000a), Mountrail (3917 kg ha−1), and Pierce (3843 kg ha−1). In those same trials, Alkabo had a 774.1 kg m−3 grain volume weight compared with 761.2 kg m−3 for Maier and 779.2 kg m−3 for ‘Lebsock’ (Elias et al., 2001a). Alkabo had a 37.4 mg kernel weight compared with 35.1 mg for Maier and 39.1 mg for Ben. Based on 28 location years in the North Dakota Research Extension Centers’ varietal trials from 2000 to 2004, Alkabo had higher grain yield (3702 kg ha−1) than Ben (3501 kg ha−1), Maier (3447 kg ha−1), Mountrail (3595 kg ha−1), and Pierce (3561 kg ha−1). In those same trials, Alkabo had a 784.4 kg m−3 grain volume weight compared with 775.4 kg m−3 for Maier and 788.3 kg m−3 for Lebsock. Grain samples from quality drill strips grown at 19 site years (2001–2003) were tested for durum wheat quality at North Dakota State University (NDSU). The semolina extraction rate of Alkabo was 64.4% on the Buhler-Miag laboratory mill at the Department of Cereal and Food Sciences, NDSU, compared with 64.4% for Mountrail, 65.1% for Ben, and 65.3% for Lebsock. Alkabo has strong gluten mixing characteristics (classifi cation: 6.5) as estimated by mixograph, compared with 7.2 for Pierce and 5.2 for Mountrail. Semolina protein of Alkabo was 136 g kg−1 compared with 137 g kg−1 of Lebsock and Mountrail. Pasta produced from Alkabo has a color score of 9.3 compared with 9.1 for Lebsock and 8.9 for Mountrail. Alkabo was evaluated at the USDA-ARS, Northern Crop Science Laboratory, Fargo, ND, for reaction to wheat stem rust (caused by Puccinia graminis Pers.:Pers. f. sp. tritici Eriks. & E. Henn) and was found to be resistant to pathotypes Pgt-QCCJ, -QTHJ, -RTQQ, -TMLK, -TPMK, and -HPHJ. Alkabo has exhibited adult plant resistance (reaction type 5R to 10R) to leaf rust (caused by P. triticina Eriks.) similar to Maier and Lebsock when evaluated in the URDN at Langdon, ND, from 2000 to 2004. On a scale of 0 to 9, where 0 is resistant and 9 is susceptible, Alkabo had average score of 4.5 Dep. of Plant Sciences, North Dakota State Univ., Fargo, ND, 58105. Registration by CSSA. Received 1 May 2006. *Corresponding author (elias.elias@ndsu.edu).