04 Jan 2016

Effects of K sources on yield and quality of Chinese cabbage in Chongqing


Both potassium chloride (KCl) and potassium sulfate (K2SO4) are commonly used in agricultural production. People used to apply KCl on grain and oil crops, but for vegetables, which fertilizer should be better is a question. In the past literatures the effects of two K fertilizers were almost same on the soils without S deficiency, but on the soil with S deficiency or sulfur -liking crops or chlorin-sensitive crops, the effectiveness of K2SO4 is better than KCl.
The result in Table 1 showed the effects of KCl and K2SO4 on Chinese cabbage. These two K fertilizers gave the same trend on crop yields which increased by K rate increase, but when K2O applied at more than 225 kg/ha, the crop yield decreased accordingly. Because Chinese cabbage is a sulfur-liking crop, the same rates of K applications gave the different results on yield increase with the effectiveness being better when K2SO4 than KCl. The results also showed on soils with sulfur deficiency, it is better to apply fertilizers with S on sulfur-liking crops. So, which K fertilizers (KCl or K2SO4 ) should be applied depend on soil S fertility and K fertilizer applied on previous crop.


Table1 Chinese cabbage yield as affected by different rates of KCl and K2SO4
K fertilizer
rate (kg/ha)
Yield (kg/ha)
Yield increase (%)
KCl
0
45675d
-
75
54150c
6.03
225
59895a
17.3
450
56550bc
10.7
K2SO4
75
54555c
6.81
225
60570a
18.6
450
58695b
14.9

More about: 西南地区