Английская Википедия:Foliar feeding
Foliar feeding is a technique of feeding plants by applying liquid fertilizer directly to the leaves.[1] Plants are able to absorb essential elements through their leaves.[2] For example,the higher Шаблон:CO2 consistently results in a lower plant foliar nitrogen.[3] The absorption takes place through their stomata and also through their epidermis.Шаблон:Citation needed Transport is usually faster through the stomata, but total absorption may be as great through the epidermis.Шаблон:Citation needed Plants are also able to absorb nutrients through their bark.Шаблон:Citation needed
Foliar feeding was earlier thought to damage tomatoes, but has become standard practice.Шаблон:Citation needed
Effectiveness
H. B. Tukey was head of Michigan State University (MSU) Department of Horticulture in the 1950s. Working with S. H. Wittwer, they demonstrated that foliar feeding is effective. Radioactive phosphorus and potassium were applied to foliage.[4] A Geiger counter was used to observe absorption, movement and nutrient utilization. The nutrients were transported at the rate of about one foot per hour to all parts of the plants.[5]
A spray enhancer, called a surfactant, can help nutrients stick to the leaf and then penetrate the leaves' cuticle.Шаблон:Citation needed
Foliar application has been shown to avoid the problem of leaching-out in soils and prompts a quick reaction in the plant. Foliar application of phosphorus, zinc and iron brings the greatest benefit in comparison with addition to soil where phosphorus becomes fixed in a form inaccessible to the plant[6] and where zinc and iron are less available.
Use
Шаблон:More citations needed section Foliar feeding is generally done in the early morning or late evening, preferably at temperatures below Шаблон:Convert, because heat causes the pores on some species' leaves to close.
References
de:Dünger#Mineralstoffaufnahme durch das Blatt
- ↑ Шаблон:Cite web
- ↑ Шаблон:Cite journal
- ↑ Шаблон:Cite journal
- ↑ Tukey, H.B., Ticknor, R.L., Hinsvark, O.N and Wittwer, S.H. (1952). Science, 116: 167–167.
- ↑ Шаблон:Cite journal
- ↑ Шаблон:Cite journal