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Cultivated peanut produces pods of varying maturity throughout most of the plant developmental stages, often leading to a considerable proportion of immature seeds at harvest. Plants originating from immature seeds not only have reduced emergence and physiological performance, but also reduced vigor of both mature and immature seeds produced in subsequent generations. Therefore, seed maturity effects on plant performance could potentially extend from physiology to the initiation and progression of reproduction. This study aimed to elucidate the impacts of seed maturity on plant performance and productivity. In this two-year experiment, season-long physiological and reproductive performance was compared among plants established from mature and immature seed of eight peanut cultivars differing in maturity potential. Our results suggest that plants produced from mature seeds had higher emergence and canopy coverage than plants produced from immature seeds over the season. Further, descendent seed quality was also affected: plants that originated from immature seeds produced mature seeds with average 9.91 % decreased mass, particularly for those formed earliest in plant development, and average 37.18 % less mature pods formed latest in plant development. At harvest, seeds were collected and tested for biochemical characteristics. Seeds that were produced by plants originating from mature seeds generally had higher carbohydrates, protein, oleic acids and lower lipid content than seeds produced by plants originating from immature seeds. Given these results, the use of mature seeds in production appears to be of utmost importance for both the performance of the subsequent plant and the resulting quality of the seed produced by these plants. • This two-year study tested peanut plant performance and the quality of their offspring seeds that formed at different time periods (represented as cohort groups) based on whether the plants and their offspring seeds originated from mature or immature seeds. • Plants produced from mature seeds had enhanced emergence and greater canopy cover than plants produced from immature seeds over the season. • Plants originating from immature vs. mature seeds produced pods/seeds differed in the numbers of mature pods, seed mass and biochemical compounds within each cohort group. • The impact of seed maturity on plant development is highly dependent to environmental influence. [ABSTRACT FROM AUTHOR]

Land use conversion of row crops to bioenergy cropping systems in the southeastern United States (U.S.) creates concerns associated with water use and NO 3 -N leaching. Production of energy from biomass is associated with large amounts of byproducts generated during biofuel processing. Biochar and vinasse are two nutrient rich byproducts that could be land-applied to bioenergy crops to reduce reliance on synthetic fertilizer. However, effects on water dynamics of applying these byproducts to support biomass production is poorly understood, particularly when bioenergy crops replace traditional row crops. Thus, this study aimed to compare a cotton ( Gossypium hirsutum L.)-peanut ( Arachis hypogaea L.) rotation to sweet sorghum [ Sorghum bicolor (L.) Moench] receiving annual applications of biochar and vinasse, on biomass yield, crop evapotranspiration, water use efficiency (WUE), NO 3 -N leaching, and soil volumetric water content. A field study was conducted from 2013 to 2015 to assess the following treatments: cotton + 150 kg N ha −1 (COT), peanut + 30 kg N ha −1 (PEA), and sweet sorghum receiving one of the following i) 30 kg N ha −1 (S30); ii) 30 kg N ha −1 + biochar (S30B); iii) 30 kg N ha −1 + vinasse (S30V); and iv) 150 kg N ha −1 (S150). Similar aboveground dry matter yields were obtained in 2013 and 2015 for cotton and all sweet sorghum treatments and were on average 19 Mg ha −1 for both years. S30 and S150 achieved similar yields. Sweet sorghum and COT exhibited the highest WUE (∼5 g kg −1 ). S30B increased soil moisture retention at 0–0.2 m depth 36, 29, and 24% in 2013, 2014, and 2015, respectively. Biochar incorporated at 0.15 m soil depth increased soil moisture retention down to 0.4 m. Low N rate application combined with biochar in S30B could represent an alternative management practice to minimize N leaching, recycle nutrients, and increase soil water retention if sweet sorghum were to be widely adopted by farmers in the southeastern U.S. [ABSTRACT FROM AUTHOR]

• Peanut is said to provide N credits to future crops in the southeastern USA but evidence is lacking to support this claim. • We evaluated wheat performance following peanut, cotton, and fallow in a conservation tillage cropping system. • Peanut residues contained up to 93 kg N ha-1, but available N at wheat planting was usually not affected by cropping history. • Peanut did not provide detectible N credits to wheat, but there were cases of lower yield after cotton relative to peanut. Agricultural extension services in many peanut (Arachis hypogaea L.)-producing regions recommend that farmers reduce nitrogen (N) fertilization rates, or apply N credits, to crops planted after peanut but do not typically specify how peanut residue management or planting schedules of subsequent crops affect the magnitude of peanut N credits. The objective of this study was to quantify peanut N credits to winter wheat (Triticum aestivum L.) in a conservation tillage cropping system in different subtropical growing environments. A five site-year study was conducted in Florida, USA beginning in 2016. A split-plot experimental design was arranged in which summer crop [peanut, cotton (Gossypium hirsutum L.), and weed-free fallow] was the main plot factor, while N rate (0, 34, 67, and 101 kg N ha−1) to winter wheat was the split plot factor. Peanut and cotton were planted under strip-tillage, while winter wheat was drilled into peanut and cotton residues and weed-free fallow plots without tillage. Although peanut residues accumulated 54–93 kg N ha−1, plant available N at winter wheat planting in the 0–15 cm soil depth range of former peanut plots was only higher than in former cotton or fallow plots for one site-year. A previous peanut crop did not affect winter wheat grain yield, but there were cases of lower grain yield, grain N removal, and agronomic efficiency following cotton relative to peanut depending on site. Nonlinear regression procedures predicted that N rates required to optimize grain yields following peanut would exceed 94 kg N ha−1, further indicating the absence of detectible peanut N credits in this study. These results suggest that assuming peanut provides N credits to subsequent crops in the southeastern USA is not justified and, if assumed, will reduce the productivity of subsequent crops. [ABSTRACT FROM AUTHOR]