Deficit drip irrigation techniques help to improve cotton production in Xinjiang, China: study

Chinese Xinjiang has the leading prestige among cotton producing regions in China and around the world due to its well-suited climate for cotton along with unique light and heat conditions. The total production of this region can be further enhanced by allocating more cultivable areas.
As compensation to declining arable lands, the cultivated area in the region is being expanded towards deserts by intensive use of anti-desertification techniques. Nevertheless, the extreme water scarcity, high evaporative potential, and negligible precipitation still remain serious concerns in desert ecosystems.

Dr. ZENG Fanjiang and Dr. GUI Dongwei from the Xinjiang Institute of Ecology and Geography (XIEG) of the Chinese Academy of Sciences, in collaboration with Dr. Muhammad Shareef from Pakistan, explored the drought adaptive and productivity potential of cotton in the desert environment with the use of deficit drip irrigation technique.

Scientists studied the quantitative interactions between key physiological and biochemical attributes in the course of drought stress adaptation, the changes in assimilates distribution pattern under stress and their impact on the quality of cottonseed and fiber. They also quantified the optimal crop water demand.

They found that, being a drought tolerant plant, cotton adapted to each level (mild, moderate, and acute) of soil water deficit stress through ameliorating its stomatal and non-stomatal attributes. This suggested that the decline in photosynthetic gas exchange activities would indeed be a modulating effect of drought induced osmoprotectants enrichment in leaf tissues.

The consumptive water demand of cotton accounted for 1079 mm to reach the highest seed cotton yield on southern border of the Taklamakan desert, while, irrigating cotton up to 80% field capacity would provide the optimum yield and net income with 20% water saving.

Studies also suggested that, no doubt deficit irrigation would assure sustainability of cotton in a desert ecosystem but, the malnourishment of fruiting fractions (boll) due to disrupted assimilates partitioning under soil water deficit would be disadvantageous for cottonseed and fiber quality parameters.

Their findings provide important insights and theoretical basis for successful and sustainable cultivation of cotton in hyperarid environment of a desert ecotone using the deficit drip irrigation techniques.

The studies are published in Agricultural Water Management, Acta Physiologiae Plantarum, and International Journal of Agriculture and Biology.