Abstract:

A solution experiment was conducted to compare the differences of the agronomic traits, dry matter and K accumulation and distribution in plant organs were studied between the transgenic Bt cotton ‘DP410B’ and the conventional cultivar ‘E8’. The culture solution K+ concentration was set the low K (K1, 2mg/L) and the appropriate K (K2, 20 mg/L) conditions. Under the same K level, the leaf number and chlorophyll content of Bt-transgenic ‘DP410B’ were higher than conventional cotton ‘E8’. Transgenic cotton had more dry matter allocated to roots, while ‘E8’ accumulated more in leaves. Potassium content of various organs and whole plant accumulation of potassium of Bt-transgenic ‘DP410B’ were greater than conventional ‘E8’. The distribution of potassium was different; the accumulation of potassium in roots and stems of the conventional cotton ‘E8’ was lower than the transgenic cotton at K2, while the accumulation of potassium in leaves was higher. Under the low potassium, the distribution proportions in each organ of two varieties were the same. Potassium efficiency of the conventional cotton ‘E8’ was 1.31 times that of the transgenic cotton, and K utilization index was also higher. These results indicated that K-use-efficiency of the conventional cotton ‘E8’ was higher, more resistant to low potassium stress. However, the yield potential of the conventional cotton ‘E8’ was little than the transgenic cotton.