Why Can't Crops Be Planted in the Same Place Twice
Knowledge snippet series: A small tip on why crops cannot be planted in the same place twice, here comes the editor's introduction to green plant maintenance.
Why Can't Crops Be Planted in the Same Place Twice
There are many reasons why some crops cannot be planted in the same place twice. One is that planting the same crop year after year can deplete certain trace elements in the soil, thereby inhibiting the growth and development of subsequent crops. For example: continuous planting of wheat can significantly reduce the phosphorus content in the soil, while planting soybeans repeatedly can decrease the bioavailability of zinc in the soil, which affects the efficiency of photosynthesis and thus reduces yield.
Reasons Why Crops Cannot Be Planted in the Same Place Twice
There are many reasons why some crops cannot be planted in the same place twice. One is that planting the same crop year after year can deplete certain trace elements in the soil, thereby inhibiting the growth and development of subsequent crops.
For example: continuous planting of wheat can significantly reduce the phosphorus content in the soil, while planting soybeans repeatedly can decrease the bioavailability of zinc in the soil, which affects the efficiency of photosynthesis and thus reduces yield.
Metals in the soil can form complexes with malic acid and salicylic acid secreted by the roots of crops like tobacco, potatoes, tomatoes, and peppers, as well as with citric acid to form chelates.
Relatively speaking, the absorption and utilization of chelates by roots is higher, which is why some crops that are not resistant to continuous cropping show severe deficiency symptoms after successive plantings.
Another point is that the excessive demand of some crops for certain trace elements leads to the depletion of these elements in the soil, resulting in deficiency symptoms.
The second reason is diseases and pests. The soil of crops that are not resistant to continuous cropping can have fungi and bacteria that parasitize on the crops.
Years of continuous cropping can make these pathogens more adapted to the soil environment of the crop, and they can also develop resistance to chemicals, affecting the normal growth of the crop roots and causing poor root growth and restricted growth of the above-ground parts.
Even with alternate-year planting, the remaining pathogens and eggs can still cause some impact, known as "sequential cropping." For example, the incidence of corn silk disease can reach 29.5% after three years of continuous cropping.
The third reason is the autotoxicity of roots. The roots of crops that are not resistant to continuous cropping secrete toxins that can poison adjacent crop roots.
In the case of continuous and sequential cropping of such crops, the toxins secreted by the roots can accumulate in the soil, causing toxic effects on the roots of the subsequent crops, leading to poor growth, reduced yield, and lower quality.
For example, phenolic acids secreted by rice can inhibit the growth of subsequent rice seedlings.
Generally speaking, many crops in rural areas are not planted on the same land for several years, mostly due to the above three reasons.
If the same practice continues year after year, diseases and pests will become more severe, and yields will decrease. Therefore, it is better not to plant crops in the same place twice.
That is all for why crops cannot be planted in the same place twice. Have green plant enthusiasts understood this?