In order to reveal effects of calcium fertilizer application and different fertilizer application on the improvement of available Ca2+ and calcium-activation on acid soil of coastal areas

experiments were conducted from 2015 to 2016 to study the effects of different fertilizer applications on available calcium content

plant characters

pod yield and kernel quality of peanut. Six treatments were single inorganic fertilizer (CK1)

inorganic/slaked lime fertilizer (T1)

inorganic/organic fertilizer (CK2)

inorganic/organic/slaked lime fertilizer (T2)

inorganic/organic/microbial fertilizer (CK3)

and inorganic/organic/microbial/slaked lime fertilizer (T3). The results showed that both CK2 and CK3 could increase the content of water soluble calcium and exchangeable calcium when compared with CK1 in some degree

for example

the average content of water soluble calcium in 0—20 cm soil layer at different growth stages increased by 48.13% and 66.50%

and the average content of exchangeable calcium increased by 39.12% and 60.88%

respectively. Calcium fertilizer treatments

such as T1

T2 and T3

significantly improved the water soluble calcium and exchangeable calcium content

but T1 showed less effect on their increase than T2 and T3. Among which

The average content of water soluble calcium and exchangeable calcium in 0—20 cm soil layer at different growth stages of T3 increased by 163% and 174% compared with CK3

respectively. These results showed that the organic fertilizer and the microbial fertilizer could significantly improve the calcium-activation in acidic soil. Different fertilizer applications significantly increased the main stem height

branch number

leaf number of main stem

dry weight per plant

leaf area index and the plant number per unit area. Different fertilizer applications also significantly increased the pod yield by increasing the pod number per plant and pod plumpness

and the treatments also improved the content of protein

total amino acids and fat

and increased O/L values. Compared with CK3

T2

CK2

T1 and CK1

the yield of T3 increased by 14.38%

4.99%

18.31%

25.65% and 52.52%

and the kernel quality of T3 was the best. Calcium fertilizer combined with organic and microbial fertilizer could increase the calcium activation degree and effective calcium content

and significantly increase the pod yield and kernel quality of peanut on acidic soil.