Table 2. Effects of potassium deficiency on the physiological characteristics of cotton xylem sap and cotton growth.

Treatment	Xylem sap volume	Protein content	pH	Root	Stem	Leaf
	ml plant−1	μg ml−1		mg dry weight plant−1
NK	0.48	4.41**	6.32**	49.6*	106.8**	196.6*
LK	0.91*	2.38	5.60	36.0	66.6	165.4

Emerging cotton seedlings in wet sand were transferred into a normal solution, grown for 3 d, and separated into a K-deficient solution and a new normal solution and grown for 7 d. These cotton seedlings were used for organ and xylem sap sampling and index determination. Means within each column followed by the * and ** are significantly different according to t-test, respectively, p < 5% and p < 1%, n = 6.