Abstract Detail

Ecophysiology

Smith, Nathan [1], Tooley, Greg [1], Maricle, Brian [2].

Effects of nitrogen fertilizer on salt-stressed milo (Sorghum bicolor).

This project aimed to investigate whether increased fertilizer would increase salt tolerance in milo. Previous studies have found that increased salt tolerance correlates to increased nitrogen fertilizer in some plants, so it was hypothesized that increased fertilizer would increase salt tolerance in milo. In this study, three nitrogen treatments (0, 50, and 150 lbs N acre^-1) and four salinity treatments (0, 40, 80, and 120 mM salt) were tested on milo plants. Weekly measures of chlorophyll concentration, height, stomatal conductance, and photosynthesis were measured for four weeks of treatment. Biomass was measured following four weeks of treatment. Plant biomass and height were reduced by increasing salinity. Any salinity above 0 mM reduced the height of plants, regardless of fertilizer concentration. Plant biomass was increased at 50 lbs N acre^-1 but was decreased at 150 lbs N acre^-1. Contrary to the hypothesis, increased nitrogen decreased many aspects of growth and performance in milo. There was a statistical interaction between salt and fertilizer for physiological measures like photosynthesis, stomatal conductance, and chlorophyll concentration. All physiological measures in 0 mM salt remained high across all fertilizer treatments. All physiological measures in 120 mM salt remained low across all fertilizer treatments. Physiological measures in 40 and 80 mM salt treatments were high in low fertilizer concentrations and became lower in high fertilizer concentrations. This indicates that increased fertilizer does not always increase salt tolerance in crop plants, as evidenced by milo.

1 - Fort Hays State University, Department of Biological Sciences, 600 Park St., Hays, Kansas, 67601, United States
2 - Fort Hays State University, Department Of Biological Sciences, 600 Park St., Hays, KS, 67601, United States

Keywords:
salt tolerance
salinity
photosynthesis
stomatal conductance.

Presentation Type: Poster
Session: P, Ecophysiology Posters
Location: Arizona Ballroom/Starr Pass
Date: Monday, July 29th, 2019
Time: 5:30 PM This poster will be presented at 6:15 pm. The Poster Session runs from 5:30 pm to 7:00 pm. Posters with odd poster numbers are presented at 5:30 pm, and posters with even poster numbers are presented at 6:15 pm.
Number: PPE002
Abstract ID:402
Candidate for Awards:Physiological Section Best poster presentation,Physiological Section Physiological Section Li-COR Prize