Toward Sustainable Intensification: Evaluating Modern Plant Density Effects on Winter Wheat Grain Yield, Quality, and Nitrogen Use Efficiency

Commodities

Practices

The objective of this project is to develop sustainable intensification systems for winter wheat cultivars via manipulation of plant densities, nitrogen rates, and sowing dates. Trials will be established in a multi-level split-plot design where sowing date will be whole plot, and nitrogen availability, seeding rate, and cultivars will be sub-plots, to evaluate grain yield, grain quality, and nitrogen use efficiency under varying environmental conditions and management practices across representative field conditions in Kansas. Sowing dates will be staggered, creating a gradient in sowing conditions, nitrogen will be applied at two contrasting levels (0 and 200 lb N/ac), and seeding rates will reflect current recommendations versus the minimum plant density for maximum grain yield found in recent studies (300 versus 100 seeds/m²). Four winter wheat genotypes differing in multiple phenotypic traits will be selected to assess interactions across diverse environments. The primary aims of this study are to i) identify how genotype × management (G×M) interactions influence grain yield, protein concentration, hardness, nitrogen uptake, and nitrogen use efficiency (NUE); and ii) assess the agronomic and economic viability of the reduction on plant densities and nitrogen inputs to inform selection strategies for sustainable winter wheat production in the region.

The beneficiaries of this proposal include:

i. Farmers and agricultural decision-makers by providing actionable insights on optimizing planting densities, nitrogen inputs, and genotype selection to improve yield, grain quality, and nitrogen use efficiency under varying environmental conditions simultaneously.
ii. Breeding programs, through the identification of potential genotype's traits with enhanced performance and/or stability under diverse management scenarios, guiding the development of improved cultivars for modern production systems.
iii. Environmental sustainability efforts by informing practices that can reduce nitrogen input requirements without compromising productivity. This contributes not only to more sustainable wheat production systems but also to a potential reduction in soil acidification and the overall carbon footprint associated with excessive nitrogen fertilizer use.
iv. Extension agents and crop advisors, offering research-based recommendations that support tailored agronomic advice to producers across Kansas and similar regions.
v. Policy makers and industry stakeholders by supporting data-driven strategies that align agricultural productivity with sustainability goals, benefiting both local economies and broader food security efforts.
vi. The overall society by increasing feed efficiency, food production, prices stability, and state and federal revenue through taxes.

In addition, the beneficiaries of this proposal extend beyond state of Kansas as regions experiencing similar environmental conditions (e.g., U.S. Great Plains).

This project is designed to answer a persistent question among producers: "How can I adopt modern management practices without disrupting current systems or increasing risk?" Farmers often hesitate to modify established operations due to concerns about added costs, staff training needs, and, most importantly, the impact on grain yield, which is a key metric universally recognized as a measure of profit for farmers.

Through this research, farmers and agricultural decision-makers will gain valuable knowledge on how genotype selection, nitrogen rates, and plant density interact under varying environmental conditions. By understanding these complex G×E×M interactions, they will be better equipped to make informed decisions that enhance yield, nitrogen use efficiency, and profit, while minimizing input waste.

Behavioral change is expected in the form of more strategic, data-informed decision-making. Farmers will begin to view nitrogen and seeding rate decisions not as fixed inputs, but as flexible tools tailored to genotype and environment. Adoption of site-specific recommendations is likely to increase, leading to more efficient resource use.

Extension advisors and agronomists will also benefit, gaining tools to translate findings into actionable field-level recommendations. In turn, breeding programs may adjust selection priorities to favor traits linked to responsiveness and stability across management systems.

Ultimately, this project encourages a shift toward precision management that balances economic and environmental goals, equipping stakeholders across the agricultural value chain with knowledge to adapt to modern production challenges.