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Carinata (Brassicacarinata) is an oilseed crop which, because of its non‐edible oil composition and favorable fatty acid profile, is proposed as a "green" sustainable aviation fuel. It can be grown as a winter crop in the southeastern USA or as a summer annual crop in northern latitudes. No crop models exist for carinata because it is a relatively new crop. The CROPGRO model is a mechanistic crop simulation of daily crop growth and development as a function of daily weather, soil properties, crop management, and species parameters. We adapted the CROPGRO model to simulate carinata based on growth analysis data collected over two seasons at three sites: Quincy, FL, Jay, FL, and Shorter, AL. The adaptation process required literature knowledge as well as optimization against field observations. The parameterization of model sensitivities to climatic factors is presented. The adapted model gave good simulations of carinata growth dynamics compared to observed growth during different seasons and locations and in response to N fertilization. While additional testing is appropriate, the model is sufficiently ready to be used for various applications. An example application is presented for the effect of sowing date on carinata yield and maturity over long‐term weather in the Southeastern USA. [ABSTRACT FROM AUTHOR]

• ENSO affected the occurrence of extreme weather events during soybean growing seasons. • Sowing date adjustments can minimize or maximize ENSO effects on soybean grain yield. • Soybean maturity groups and sowing dates can affect the exposure to extreme weather events. With current annual production of over 110 million metric tons, US soybean [ Glycine max (L.) Mer.] grain production can drop drastically due to extreme weather. The record heat and drought of 2012, a La Niña year, caused a 10% decline in national soybean yield. Inclement years are often linked to El Niño-Southern Oscillation (ENSO) phenomenon, causing drought, heavy rainfall, or extreme temperatures. Thus, management strategies to minimize impact of extreme weather events (EWE) on soybean crop growth are important for the sustainability of farming systems. In this study, we evaluate how soybean sowing date and maturity group (MG) can mitigate the effects of ENSO on yield variability in the Southeastern US. A calibrated DSSAT-CROPGRO-Soybean crop model for three MGs (5.6, 6.1, and 7.0) was used to simulate yield and quantify the occurrence of extreme weather events (EWE) during vegetative and reproductive soybean stages. Historical (36 years, between 1984 and 2019) soybean yield simulations were conducted using ten different sowing dates ranging from April to early August, at eight locations across the Southeastern US. Additionally, data analyses were performed using principal component analysis to understand the major factors of soybean yield variability in this region and which management conditions could reduce the impact of EWE. Our results showed that soybean yield variability could be minimized through the adjustment of sowing dates according to ENSO phases that also impact the occurrence of EWE during reproductive and vegetative stages in this region. [ABSTRACT FROM AUTHOR]

Brassica carinata is usually grown in a double-cropping system with cotton and peanut in southeastern USA. One challenge related to this system is to define the best sowing dates to minimize the climatic risk and improve the chances for increased farmers' profitability. The objective was to determine the best sowing dates for carinata-cotton and carinata-peanut double-cropping systems in different locations of the southeastern USA. A calibrated crop simulation DSSAT model was used to simulate carinata life cycle and cotton and peanut yields for 9 locations in 4 states, with carinata sowing dates ranging from early September to March using 38 years of weather data (1981–2018), assuming that cotton and peanut sowing occurred immediately after the carinata harvest. Results indicated that the optimal sowing date varied according to location. For Shorter, AL, Midville, GA, and Florence, SC, the occurrence of extreme weather events during carinata cycle were minimized, and the summer crop yields were the highest when carinata was sown at the end of October. For Fairhope, AL, Jay, and Quincy, FL, results showed that carinata sowing must occur in early November to minimize the climatic risks of a double-cropping system. For Live Oak and Citra, FL, carinata sowing is recommended for mid- to late-November. Advancing carinata sowing to September resulted in an increased number of low temperature (LT) events during the carinata reproductive phase. The delay in carinata sowing to January or later exposed carinata crop to a larger number of High Temperature (HT), and considerably reduced the yield potential of the peanut and cotton summer crops. Our results quantified the climatic risks to the off-season carinata crop itself and to the subsequent summer crop, contributing to the sustainable expansion and commercial production of carinata in the southeastern USA. [Display omitted] • Double cropping system with carinata and summer crops could promote biofuel production in USA, but present climatic risks. • Optimal sowing date could minimize the occurrence of frost, droughts, heat and heavy rainfall events during carinata cycle. • Carinata sowing should occur between late October and November to maximize the yield of summer crops. • Reduced climate risk is key to the sustainable expansion and commercial production of carinata in the southeastern USA. [ABSTRACT FROM AUTHOR]