Registration of 20 Tropical Midaltitude Maize Line Sources with Resistance to Gray Leaf Spot

Abstract

Registration of 'Oklee' Wheat relatively early maturing and produces spikes 1.3 d earlier 'Oklee' is a hard red spring wheat (Triticum aestivum L.) than 2375 and 0.6 d earlier than Oxen (PI 596770), the most (Reg. no. CV-963, PI 634553) developed and released by the widely grown cultivar in Minnesota since the late 1990s. Oklee Minnesota Agricultural Experiment Station in cooperation is a semidwarf cultivar and averages 75 cm, the same height with USDA-ARS in January 2003. It was named after a town as Oxen, and is 3 cm shorter than 2375 in Minnesota trials. in its region of adaptation in northwest Minnesota. Oklee was In 35 Minnesota trials conducted from 1998 through 2002, released on the basis of its high grain yield, high grain volume Oklee yielded 3664 kg ha Ϫ1 compared to 3482 kg ha Ϫ1 for weight, high grain protein content, and early maturity. In addi-2375 and 3825 kg ha Ϫ1 for Oxen. Oklee was evaluated in tion, Oklee has moderate resistance to Fusarium head blight 29 environments in the Uniform Regional Hard Red Spring (FHB, caused primarily by Fusarium graminearum Schwabe). Wheat Nursery in 1998 and 1999 and yielded an average of Oklee was derived from the cross '2375'/SBF0670, made 3456 kg ha Ϫ1 compared to an average of 3470 and 3503 kg by the former Pioneer Hi-Bred spring wheat breeding program ha Ϫ1 produced by the check cultivars, 2375 and Verde (PI in the USA. The cultivar 2375 (PI 601477, syn. Pioneer 2375) 592561, Busch et al., 1996), respectively. Oklee has moderately has the pedigree Olaf//Era/Suqamuxi 68/3/Chris/ND487//Lark strong straw and a lodging rating of 2.3 when scored on a and was widely grown in Minnesota during the mid-1990s due scale of 0 (erect) to 9 (lodged) in 21 environments at which to its moderate resistance to FHB. SBF0670 is an unreleased lodging occurred from 1998 thru 2002. By comparison, the line whose pedigree contains hard red spring lines once promicultivars 2375, Oxen, and Verde had lodging ratings of 3.5, nent in the region including 'Chris' (CItr 13751, Heiner and 2.6, and 2.1, respectively. Johnston, 1967), 'Era' (CItr 13986, Heiner and McVey, 1971), Oklee has moderate resistance to FHB in misted, inoculated and 'Butte'. field nurseries, similar to the resistance of 2375. In 11 FHB The F 2 population producing Oklee was selected for leaf nurseries from 1998 through 2001, Oklee averaged 23.6% disrust (caused by Puccinia triticina Eriks.) and stem rust (caused eased spikelets, 16.7% visually scabby kernels (VSK), and by Puccinia graminis Pers.: Pers.) resistance in a field planting 8.8 mg kg Ϫ1 of the mycotoxin deoxynivalenol (DON). The at St. Paul in 1993. The F 3 generation was advanced by single cultivar 2375 averaged 22.7% diseased spikelets, 17.5% VSK, seed descent in a greenhouse. The selection resulting in Oklee and 9.8 mg kg Ϫ1 DON. In the same trials, the resistant check was selected from a single plant in an F 4 headrow in 1994 and 'BacUp' (PI 596533, Busch et al., 1998) and the susceptible this seed was increased in a winter nursery in Arizona during check ...

Genotype × environment interaction of quality protein maize grain yield in Nepal

“…This finding was similar to findings of Carson et al (2002). The significantly different G × E interactions was recorded for grain yield in maize (Makumbi, 2005;Menkir & Ayodele, 2005). The Figure 2 indicated that the performance of SO3TLYQ-AB-01 seemed better for Pakhribas.…”

Efficiency of selection per se and in single-cross hybrids for disease resistance in maize

“…Estimates of gain from selection directed by per se performance of the lines regarding resistance to white spot (WS), common rust (CR), the proportion of ears with ear rot (PER), score given to ears for severity of damaged kernels (SCO), and percentage of damaged kernels (DK%). These results show that the reaction to WS and ER in the hybrids and the lines was interrelated, as described by Hung and Holland (2012) and Menkir and Ayodele (2005), who conducted their studies evaluating maize pathosystem-damaged kernels and leaf diseases, respectively. The association between these generations is explained by the predominance of additive effects in control of resistance to these diseases.…”

“…Furthermore, concentrating efforts in the diallel analysis, it is possible to perform a broader study of adaptability and stability during the studies of genotype selection and simultaneously identify parents that upon being used in crosses express not only resistance to these diseases, but also characteristics of agronomic interest (Menkir and Ayodele, 2005).…”

Combining Ability, Genetic Distances, and Heterosis among Elite CIMMYT and IITA Tropical Maize Inbred Lines

“…The lines were selected to represent the most elite lines from each side of the major heterotic pattern used by these breeding programs. Among the IITA lines, TZMI801, TZMI702, TZMI703, and TZMI704 were derived from crosses with 50%, and TZMI802 with 25% contribution from the broad‐based population TZMSR (Menkir and Adepoju, 2005), while CIMMYT's CML216 was derived directly from TZMSR and CML395 from a cross with 50% of this population (Everett et al, 1994a, 1994b; CIMMYT, 1998). Other known relationships among the lines were i) TZMI702, TZMI703, and TZMI704 were derived from the same biparental cross; ii) CML489 traces 50% of its pedigree to CML202; and iii) TZMI803 and CML444 were both derived from CIMMYT's broad‐based Population 43 (Table 1).…”