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Prohexadione calcium is a growth regulator, which manages excessive vine growth in peanut (Arachis hypogaea L.) by reducing shoot internode length. To test the effect of prohexadione calcium on peanut, a field experiment was conducted at the West Florida Research and Education Center in Jay, FL, during 2021 and 2022. The objective was to determine peanut response at different rates (untreated control, 70, 105, 140, and 175 g a.i. ha−1 of prohexadione calcium). Data were collected on yield, peg strength, above‐ and belowground biomass, plant height, and total sound mature kernels. Additionally, return on investment for prohexadione calcium application was also calculated. Prohexadione calcium application resulted in significant reduction of peanut plant height. The application rate of 105 g a.i. ha−1 resulted in significantly greater normalized difference vegetation index as compared to untreated control. Belowground, aboveground, and total biomass did not significantly differ between the 140 g a.i. ha−1 rate and untreated control. However, peanut peg strength increased significantly at the 140 g a.i. ha−1 treatment compared to the untreated control. Peanut yield ranged from 6.65 to 7.15 Mg ha−1 among different treatments; however, the differences among treatments were not significant. Similarly, the total sound mature kernels and return on investment did not differ significantly under different prohexadione calcium treatments. Considering that peanut response to prohexadione calcium is difficult to observe in small plots, it is important to test the effect of prohexadione calcium on peanut production under on‐farm large plot conditions. Core Ideas: Prohexadione calcium significantly reduced peanut plant height under all rates.Peanut peg strength improved significantly under labeled rate (140 g a.i. ha−1).Reduced rates (105 g a.i. ha−1) of prohexadione calcium showed similar yield as labeled rates (140 g a.i. ha−1).Greater return on investment was observed under reduced rates (105 g a.i. ha−1). [ABSTRACT FROM AUTHOR]

Best management practices that optimize agronomic performance and make Brassica carinata production compatible with existing cropping systems are crucial for the establishment of a carinata supply chain in the southeastern United States. To this end, research was carried out to quantify land preparation method (conventional, no-till, broadcast-disc, and ripper-roller) and seeding rate effects on (1.12, 5.60, 10.09, and 14.57 kg seed ha−1) on B. carinata physiology, yield, and seed chemical composition. Data were collected on days to 50% flowering; canopy cover; gaseous exchange parameters (leaf net photosynthesis, stomatal conductance, transpiration, intercellular CO2, and water use efficiency); leaf area index; root weight; shoot weight; aboveground biomass; yield; and seed chemical composition. Leaf net photosynthesis was affected by land preparation treatment, being greater under the ripper-roller treatment, particularly during bolting. On the other hand, a decrease in photosynthesis, stomatal conductance, and water use efficiency was observed as seeding rate increased, especially during bolting. Carinata seed under the ripper-roller land preparation had the greatest oil content but lowest glucosinolates and protein contents. Yield did not respond to land preparation. Yield was minimized (732 kg seed ha−1) at the 1.12 kg ha−1 seeding rate and maximized (1087 kg seed ha−1) at the 5.6 kg ha−1 seeding rate. No land preparation by seeding rate interaction was observed for gas exchange parameters and LAI during any of the growth stages, nor was any interaction observed for yield. Carinata's physiological response to seeding rate did not depend on land preparation method employed. [ABSTRACT FROM AUTHOR]