Sorghum growth

Data summarizing the effects of the inhibitory weed extracts on sorghum water status was taken from the second trial in each case (Table V). All of these extract treatments had reduced sorghum growth, and all but one had some effect on plant water balance. 

Relating the effects caused by specific allelochemicals to those caused by an allelopathic plant is complicated because the inhibitory substances released from a plant are often unknown, and generally several different compounds are involved. However, the actions of the weeds studied in our investigations have certain parallels to those found from pCA and FA. The allelopathic nature of Kochi a, Jerusalem artichoke, and cocklebur was established, since both aque-ous extracts and weed residues reduced sorghum growth. The data show a concentration dependency characteristic of allelopathy, and some difference in toxicity among the three weeds was observed with cockle-bur the most toxic. 

Fig. 5. Growth curve and PHAs production during batch fermentation of sweet sorghum by Bacillus arybhattai in 3 L fermentor (Tanamool et al., 2011)...

Ludlow, M.M. Powles, S.B. (1988). Effects of photoinhibition induced by water stress of growth and yield of grain sorghum. In Ecology of Photosynthesis in Sun and Shade, ed. J.R. Evans, S. von Caemmerer and W.W. Adams III, pp. 179-94. Melbourne CSIRO. 

Blum, A. Arkin, G.F. (1984). Sorghum root growth and water-use as affected by water supply and growth duration. Field Crops Research, 9,131-42. 

Blum, A., Arkin, G.F. Jordan, W.R. (1977). Sorghum root morphogenesis and growth. I. Effect of maturity genes. Crop Science, 17,149-53. 

Kochi a residue levels of 2.5% significantly altered sorghum water balance, and plants grown in soil with cocklebur residues above the growth-inhibition threshold showed a trend toward elevated leaf resistances and lower water potentials than controls. A lower growth-... 

Einhellig and Rasmussen (17) reported that In addition to ferulic and p-coumaric acids, vanillic acid reduced chlorophyll content of soybean leaves but did not affect chlorophyll In grain sorghum fSorghum bicolor (L.) Moench.]. It Is not known whether these reported mechanisms are primary or secondary events In the Inhibition of plant growth by allelochemlcals. 

Selection of a bloassay depends on the growth parameters to be measured and the quantity of allelochemlcal available. For example, the sorghum seedling bloassay used In our studies may be the best for determining the uptake, distribution, and metabolism of known allelochemlcals where quantity of compound Is not a factor and the use of radiolabeled materials would be expedient. 

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