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Wheat (Triticum aestivum L.) production in Texas depends heavily on conventional tillage (CT) and a long summer fallow period, which contributes to soil degradation. This study compared the impact of reducing tillage intensity (CT, no‐tillage, and strip‐tillage) combined with summer cropping to CT–summer fallow on wheat establishment, grain production, and herbage mass from 2016 to 2020 in three Texas ecoregions (Coastal Plains, Southern High Plains, and Blackland Prairie). Tillage and summer cropping resulted in variable impacts on wheat stand establishment, grain yield, and herbage mass across years and locations. At Beeville, in the Coastal Plains, wheat grain and herbage mass yields were not impacted by tillage. Sorghum (Sorghum bicolor [L.] Moench) cropping resulted in less wheat grain yield in 2020. In 1 yr at Lubbock in the Southern High Plains, wheat grain yield was greater with CT than reduced tillage. Sorghum summer cropping resulted in lower wheat grain yield than cover crop mixture or cowpea (Vigna unguiculata [L.] Walp.) in 2017, but yield was greater in 2020. At Thrall, in the Blackland Prairie, wheat stand establishment and yield with reduced tillage were greater than CT in 2016, whereas CT was greater in 2017 and 2020. Sorghum or cover cropping resulted in reduced wheat grain yield compared with fallow in 2018, but sorghum and sesame (Sesamum indicum L.) resulted in increased yield compared with fallow in 2019 and 2020. Summer cropping in wheat production systems rarely had a negative impact on wheat production compared with summer fallow in all three ecoregions. Core Ideas: Tillage and summer cropping had variable effects on yield and herbage mass across semi‐arid environments.Conservation tillage practices, no‐tillage, or strip‐tillage are feasible practices for wheat production systems.Wheat–summer crop rotations are potentially feasible systems in the Coastal Plains and Blackland Prairie regions.Wheat–summer crop rotations are not feasible in the Southern High Plains due to limited precipitation and timing. [ABSTRACT FROM AUTHOR]

Silage is an alternative product from sorghum [Sorghum bicolor (L.) Moench] that does not make grain due to drought, disease, or pests. The objective of this experiment was to determine nutritive value and fermentation characteristics of silage made from sorghum without grain and evaluate the impact of pretreatment with fibrolytic enzymes or lactic acid bacterial inoculants. Triplicate plots (4 rows ×12.2 m) of four sorghum cultivars (Dairy Master, PS 747, Silo 700D, and MMR 381/73 [MMR]) were planted in a completely randomized block design field trial at three locations (Beeville, College Station, and Kingsville, TX). At the mid‐dough stage, sorghum was harvested and inflorescences were removed, chopped, and separated into three (5 kg) subsamples. Each subsample was treated with either distilled water (control), fibrolytic enzyme, or bacterial inoculant and ensiled for 120 d. Pre‐ensiled sorghum without grain had similar nutritive value, except Dairy Master had 25% lower crude protein and 30% lower lignin concentrations. After ensiling, water‐soluble carbohydrate concentration was lowest and crude protein concentration was greatest for MMR silage, which also had the greatest acetate concentration and lactate/acetate ratio. Silage treated with either lactic acid bacterial inoculant or fibrolytic enzyme had 40% greater water‐soluble carbohydrate concentration. Silage treated with fibrolytic enzyme had 8% lower neutral detergent fiber and acid detergent fiber concentrations than untreated silage, and treated silage had lower pH than untreated silage. The pH of all silage was <4.0, and pretreatment did not improve silage fermentation characteristics or increase aerobic stability. The cultivar was more influential to the resulting silage product than pretreatment in this experiment. [ABSTRACT FROM AUTHOR]

Conventional tillage (CT) cropping systems in semiarid regions of south Texas are associated with soil degradation and increasing fuel costs. The objective of the study was to evaluate the effects of no-till (NT) compared with CT on a dryland cotton (Gossypium hirsutum L.)-grain sorghum [Sorghum bicolor (L.) Moench] rotation system with respect to crop yields, yield stability, soil moisture and structure, and economics. The experiment (four replicated plots of each crop and tillage treatment annually) was conducted on a Vertisol at Corpus Christi, TX, from 2011 to 2015. Cotton yield was similar among tillage treatments, except for the drought year of 2013 when 86% greater yield occurred with NT and above average precipitation year of 2015 (15% greater yield for NT). Sorghum yield was impacted by tillage in 2012 when NT produced 33% greater yield than CT, whereas, in 2015, CT produced 28% greater yield. Yields were stable across crops and tillage treatment. Soil moisture was not impacted by tillage treatment; however, tillage caused bulk density to increase at 15- to 30-cm depth compared with 0- to 15-cm depth. All soil chemical properties remained constant, except NT had greater total soil N than CT in 2015. Cash costs for CT were greater than NT for both crops, and net cash farm income was positive only for NT cotton. No-till is a viable alternative for dryland farmers in this region because of stable yields and increased income. [ABSTRACT FROM AUTHOR]

Biofuels produced from non-food lignocellulosic feedstocks have the potential to replace a significant percentage of fossil fuels via high yield potential and suitability for cultivation on marginal lands. Commercialization of dedicated lignocellulosic crops into single biofuels, however, is hampered by conversion technology costs and decreasing oil prices. Integrated biorefinery approaches, where value-added chemicals are produced in conjunction with biofuels, offer significant potential towards overcoming this economic disadvantage. In this study, candidate lignocellulosic feedstocks were evaluated for their potential biomass and silica yields. Feedstock entries included pearl millet-napiergrass ("PMN"; Pennisetum glaucum [L.] R. Br. × P. purpureum Schumach.), napiergrass (P. purpureum Schumach.), annual sorghum (Sorghum bicolor [L.] Moench), pearl millet (P. glaucum [L.] R. Br.), perennial sorghum (Sorghum spp.), switchgrass (Panicum virgatum L.), sunn hemp (Crotalaria juncea L.), giant miscanthus (Miscanthus × giganteus J.M. Greef and Deuter), and energy cane (Saccharum spp.). Replicated plots were planted at three locations and characterized for biomass yield, chemical composition including hemicellulose, cellulose, acid detergent lignin (ADL), neutral detergent fiber (NDF), crude protein (CP), and silica concentration. The PMN, napiergrass, energy cane, and sunn hemp had the highest biomass yields. They were superior candidates for ethanol production due to high cellulose and hemicellulose content. They also had high silica yield except for sunn hemp. Silica yield among feedstock entries ranged from 41 to 3249 kg ha−1. Based on high bioethanol and biosilica yield potential, PMN, napiergrass, and energy cane are the most promising biorefinery feedstock candidates for improving biofuel profitability. [ABSTRACT FROM AUTHOR]