A flood-free period combined with early planting is required to sustain yield of pre-rice sweet sorghum (Sorghum bicolorL. Moench)

Abstract

Publication details, including instructions for authors and subscription information: http://www.tandfonline.com/loi/sagb20 A flood-free period combined with early planting is required to sustain yield of pre-rice sweet sorghum (Sorghum bicolor L. Moench) AbstractUnderstanding the responses of sweet sorghum to flooding and the characters associated with flooding tolerance may be a useful strategy for pre-rice production and help meet demand for biofuel feedstock. Three sweet sorghum genotypes (Bailey, Keller and Wray) and five flooding treatments including non-flooding control, continuous flooding extended from 30, 45, 60 and 75 days after emergence to harvest were conducted under greenhouse conditions. Flooding decreased leaf dry weight (22Á60%), leaf area (10Á70%), number of node per stalk (1Á5%), shoot dry weight (5Á20%) and stalk yield (2Á22%) with highest reduction in 30 days after emergence flooding treatment. Flooding later than 30 days after emergence did not significantly affect shoot growth, yield and yield components. Brix value, sucrose content and total sugar content were not significantly affected. All studied cultivars had similar shoot growth response. Flooding induced development of roots in water; root length, root dry weight, nodal root and lateral root number and interconnection of aerenchyma spaces from roots in flooded soil to stalk base above water level but suppressed root growth in flooded soil. The acclimation traits were highest in Keller, flooding from 30 days after emergence but there was a lack of root development in 75 days after emergence flooding treatments. These findings indicate the effect of waterlogging on sweet sorghum growth and yield strongly depends on the growth stage at which it occurs. There were genetic variations in root morphological and anatomical responses to flooding of sweet sorghum. The development of nodal and lateral roots and aerenchyma formation from flooded plant parts to stalk bases above water level may distribute to flooding tolerance in sweet sorghum. Based on the results, a flood-free period of at least 30 days after emergence is required to sustain yield of pre-rice sweet sorghum and early planting is highly recommended.

Response of Sorghum to Abiotic Stresses: A Review

“…Flooding later than 30 days after emergence did not significantly affect shoot growth. However, there were genetic variations in the response of the root system to waterlogging, and several genotypes responded with aerenchyma formation from the roots to the stalk base in flooded soils (Promkhambut et al 2011b). Development of new nodal roots appeared to be also an adaptive response of sorghum to waterlogging (Pardales et al 1991).…”

Physiological responses of Medicago truncatula growth under prolonged hypoxia stress

“…The lack or the excess of the water in the rhizosphere present a critical factor on plant growth. Indeed, drought or waterlogging affect plant characteristics (Iqbal et al, 2009;Ibraheem et al, 2011;Promkhambut et al, 2011). Flooding is one of the most significant abiotic stresses, it causes a slow transfer of dissolved oxygen in the waterfilled pore space of the soil, and plants can have to face to the lack of oxygen during all stage of its growth.…”

A multiple harvest cultivation strategy for ethanol production from sweet sorghum throughout the year in tropical ecosystems

“…The extensive flooding reduced plant height, leaf area, photosynthetic and transpiration rates. In a second study [21] flooding was induced in Wray, a sweet sorghum variety, and a multipurpose sorghum cultivar at three plant development stages, early vegetative, early reproductive and mid reproductive stages. Plant height, stem diameter, leaf area and dry weight, shoot dry weight, primary root length and root dry weight of both cultivars were significantly reduced by flooding at the early vegetative and reproductive stages, but not at the mid reproductive stage.…”