Performance of Sweet and Forage Sorghum Grown Continuously, Double‐Cropped with Winter Rye, or in Rotation with Soybean and Maize

Abstract

Double‐cropping sorghum [Sorghum bicolor (L.) Moench] with winter rye (Secale cereale L.) could increase annual dry matter production in the North‐Central region of the USA and reduce soil erosion and other environmental concerns. We conducted this study to compare yield, chemical composition, erosion potential, and economics of sorghum grown continuously (sole crop), in a 3‐yr rotation with maize (Zea mays L.) and soybean [Glycine max (L.) Merr.], or double‐cropped with winter rye (rye‐sorghum). The experiment was on a Typic Calciaquoll soil in central Iowa with a slope of less than 1% and on mixed Vertic Argiaquoll, Typic Hapludoll, and Aquertic Argiudoll soils in southern Iowa with 2 to 7% slope. Applied N moderately affected sole‐cropped sorghum, with yields of 13.5, 16.1, 16.9, and 15.9 t ha−1 when fertilized with 0, 70, 140, and 280 kg ha−1 N, respectively. Rye‐sorghum was highly responsive to N, with combined yields at 72, 84, 95, and 110% of sole‐cropped sorghum fertilized with the same annual rate of N. Drought dramatically reduced rye‐sorghum yields. Sole‐cropped sweet sorghum had yields similar to sweet sorghum grown in the 3‐yr rotation. Environmental conditions associated with years and locations affected fiber components, N, and total nonstructural carbohydrate concentrations of sorghum. Use of the Universal Soil Loss Equation revealed that planting rye before sorghum would reduce estimated soil loss at both locations, but the loss was still unacceptably high on the sloping soil in southern Iowa (22 t ha−1). An economic partial budget showed that ryesorghum cost $147 ha−1 more to produce than sole‐cropped sorghum. We conclude that, if winter rye is to be grown as a double crop with sorghum in the North‐Central region, it will likely be because of its positive influence on the environment and not because of potential for improved yield.

Selecting Sorghum Forages for Limited and Full Irrigation and Rainfed Conditions in Semiarid, Subtropical Environments

“…No difference occurred between years and no year × sorghum forage type interaction resulted for FULL (Table 3). This lack of any year effect on yield indicates the ability of sorghum forage to maintain consistent production when adequately supplied with water even though other management factors such as seeding rate and fertility (2) vary to a degree (Table 2). Yields of SS were greater than FS within FULL.…”

“…Sorghum grown for grain or forage is more water use efficient than other crops (2,8), tolerates drought well (4,15), and can maximize yield with low to moderate nitrogen inputs (2). Sorghums also can grow in areas in which the amount or distribution of precipitation and irrigation is not suitable for corn (2,5,8). Sorghum forages are not as sensitive to moisture stress as grain sorghum (16) and can be produced within a broad range of management practices, including varied planting dates and rates, varied fertility and irrigation levels, and different harvest and post‐harvest storage techniques (7).…”

Nitrogen Efficiency and Nutrient Absorption by a Sorghum-Oats Forage Succession

“…Sorghum sp is characterized as C 4 physiology, presenting a great forage yield with a high nutritional quality, with high carbohydrates content [8,9], a great potential for ethanol [10,11], and biodiesel use [12], and is also an effective crop for soil protection [13]. This 2 Advances in Agriculture Nov.…”

Cover crop and tillage affect sweet sorghum production and soil chemical properties

“…Environmental conditions associated with year and experimental site can affect fiber composition and nonstructural carbohydrate concentration in sweet sorghum (Buxton, Anderson, & Hallam, ). Pooled sweet sorghum performance parameters of the current study indicated some interesting correlations between the agronomic parameters.…”