Variety, seeding rate, and nitrogen fertilization effects on yield and quality of wheat

In the spring of 1970 a field study was conducted at Fresno State College to evaluate the impact of genotype, seeding rate, and nitrogen fertilization level on some growth and quality characteristics of wheat. Two relatively new wheat genotypes, generally good for making quality baking flour, developed in Mexico were chosen for their short stature and grain composition. These varieties, which under normal growing conditions produce grain suitable for baking purposes, make it possible to study the effects of ranges in seeding and fertilization rates on the growth and subsequent yield and quality of the wheat. Inherent genetic differences were responsible for differences in grain protein content and gluten strength between varieties. Higher seeding rates resulted in increases in yield and plant growth. Seeding rates had no effect on grain protein content or flour gluten strength. Nitrogen fertilization increased both yield and plant growth, but excessively high levels resulted in a yield depression. Grain protein content was raised by higher nitrogen fertility levels while bushel weight and kernel weight were reduced. At lower nitrogen fertility levels, yield increased faster than protein content; while at higher levels, protein content increased faster than yield. Farinograph curves showed that increasing nitrogen fertility resulted in flour with greater gluten strength.