Carbohydrates and organic acids have been reported to accumulate in stress-hardened cotton plants. In this study, boll-producing cotton plants (Paymaster 404) were maintained under both waterdeficit (dryland) and irrigated field conditions and monitored from 60 to 105 days after planting MAP). Both dryland and irrigated plants developed bolls from approximately 65 DAP. The organic acid and carbohydrate profiles and compositions of stressed (dryland) plants and corresponding irrigated controls were determined by high performance liquid chromatography (HPLC). Individual components were quantitated on the bases of leaf surface area and freshweight.

The organic acids (malic, citric, and oxalic) and the carbohydrates (sucrose and glucose) were present at the same levels for both the dryland and irrigated were similar and gradually increased from 61 to 87 DAP, whereupon the levels for the stressed increased more than the irrigated did. The organic acid levels for the dryland plants fluctuated extensively throughout the period sampled. In contrast, organic acid values for the irrigated controls decreased after 68 DAP and remained at approximately the same level until 103 DAP. Citric to malic acid ratios were not different for stressed and irrigated up to 87 DAP after which differences appeared until 103 DAP.

Overall, the total organic acids and carbohydrates for the dryland samples were maintained at higher levels than the irrigated samples from 68 DAP on. This difference increased with increasing age of the plants to a maximum of 2.5:1 at 87 DAP for the ratio of dry/irrigated values.