The important agronomic traits of the durum industry are high yield, test weight, kernel weight, maturity, plant height, and lodging resistance. 

Grain yield

Grain yield in durum wheat is a complex character with several components that include genetic and environmental factors. The objective of the breeding program is to continue increasing yield without sacrificing quality.  The new released cultivars Divide, Grenora, Aakabo, and Pierce have higher yield and superior quality than the older varieties Renville and Monroe.  

Plant height

Plant height is a major agronomic character in durum wheat because of its association with lodging.  Plant height is controlled by growing environment and by many genes having both major and minor effects.  Before 1940, most of the North Dakota durum wheat cultivars were very tall (150 cm) and susceptible to lodging.  Reducing plant height of North Dakota cultivars became a major objective of the breeding program. In 1940, North Dakota State University used the cultivar Heiti to reduce plant height and lodging.  Further reduction in plant height occurred when the dwarfing gene Rht1, which is derived from the hexaploid wheat source Norin10/’Brevor’, was transferred to North Dakota’s durum germplasm.  The current objective of the NDSU breeding program is to develop medium height (90 to105 cm) with strong straw durum wheat cultivars.   An example of these cultivars are Munich, Ben, Mountrail, Lebsock, Maier, Grenora, Alkabo, and Divide.

Maturity

The durum wheat germplasm in North Dakota has a spring habitat. Grain yield generally is greater with  late-maturing than with early maturing lines. However, late-maturing lines can be adversely affected by frost before harvest.  Therefore, the objective of the breeding program is to release medium-maturing cultivars.  The medium maturing-cultivars have high yield and mature before frost.  Days to heading, measured as the number of days from seeding to the date when approximately 50% of plants had heads completely emerged from the boot, is used as an indirect selection for maturity.  The average days to heading of desired durum cultivars in North Dakota is 60 to 65 days.