China and India are main counties of grain production, and how to plant crops well has become an international issue. Now, manganese (manganese sulfate) deficiency occurs frequently in some areas. Following are some information and tips on how to prevent crops from manganese deficiency.
The content of Mn in healthy plants is about 50-100ppm, deficient plants will be shorter, with fewer tillers and small leaves. Necrotic brown spots develop later and leaves become to dark brown and then will be necrosis gradually.
So what are the reasons for manganese deficiency crops？
I: Effective Mn content in soil decreased.
II: The soil reaction gets stronger, manganese transformed into insoluble matter.
III: Fe-induced Mn deficiency, due to a large concentration of Fe in the soil. Increased Fe absorption reduces Mn uptake in rice plants.
According to the experts, manganese deficiency should be treated as follows:
I: Treat agriculture grade manganese sulfate as base fertilizer, manganese sulfate 2kgs/667m2 be used together with farm manure or other organic fertilizers for furrow application or hole application
.II: Seed dressing with manganese sulfate solution. Dissolve manganese sulfate by little water, and then spray it onto seeds. The ratio: 1kg seeds need 4-8g Mn. Mix then well while spraying, and then you can sow after drying them out.
III: Soaking seeds with manganese sulfate solution. Soaking seeds with 0.1% manganese sulfate solutions at the ratio of 1:1, and then you can sow after drying them out.
IV: Spraying manganese sulfate solutions onto plant. Spray plant three times in their seedling period and growth period separately. The ratio should be 50-75L/667m2, with 0.1%-0.2% manganese sulfate
We should pay more attention to judge whether the plants are manganese sulfate deficiency or not, cause the symptom is similar with zinc deficiency and magnesium deficiency.