Terms and definitions

The neem tree has various names: Egyptian Acacia, Indian Lilac (because of its violet leaves but not to be confused with Lagerstroemia indica which is also referred to as Indian Lilac), Margosa, Persian Lilac and China Berry. Vernacular names: Nim, Neem, Balnimb (Hindu), Nimba (Sanskrit), Vepu, Vempu, Veppam (Tamil), Vepa (Telugu), Limba (Gujarat). Its name means "Cure-all".

Rainfall ideally between 400 and 1,200 millimetres but the tree may thrive at lower levels if the water table is high enough. It is adapted to sandy or well-drained soils (pH 6.2-7.0) and poor soil-types. It grows well at temperatures of between 21°C and 32°C and can tolerate very high temperatures but not below 4°C

A mature neem tree can produce up to 50 kilograms of fruit, i.e. 30 kilograms of seeds. It is the seed that is the main source of insecticide compounds, including azadirachtin. The amount of azadirachtin in the seeds depends on climate, soil conditions and genotype (Ermel 1986 ; Singh 1986).

Foliar fertilisation involves spraying the fertiliser directly onto the leaves of a plant. This type of fertilisation is very fast-acting because nutrients can be assimilated and used straight away. Foliar fertilisation is particularly effective at times of stress (grafting, hail, winf, cold, heat, drought) or if some nutrient is severely deficient. It is especially relevant for one-off fertilisation to compensate for a short-term deficiency problem. For a longer-term solution, the cause of the imbalance needs to be addressed, e.g. if the mineral deficiency results from low pH, the soil will have to be modified. Nutrients in the fertiliser penetrate the leaves via tiny openings called stomata which are usually denser on the lower side of the leaf. This should be taken into account when applying the fertiliser, focusing the spray on the underside of the leaves. The leaves absorb the fertiliser more efficiently if it is applied early in the morning or in the evening when the air is cool and more humid (which promotes opening of the stomata).

The arthropods (Arthropoda: from the Greek arthron meaning joint and podos meaning foot) are a class of invertebrate animal. The arthropod body is composed of jointed segments (metameres) covered with a stiff cuticle which constitutes their external skeleton. In most cases, this is based on chitin. The class of Arthropoda includes by far the greatest number of species and individuals in the entire animal kingdom. Currently, more than one-and-a-half million different arthropod species are known.

An ovicide phytosanitary product is an active substance or preparation that inhibits egg development by killing the embryo. In the protection of crops against parasites, it is important to understand the ovicidal properties of the phytopharmaceutical products applied, and know the date of egg-laying, so that insecticide and acaricide use can be rationalised.

A larvicide phytosanitary product is an active substance or preparation that kills larvae. In the protection of crops against parasites, it is important to understand the larvicidal properties of the phytopharmaceutical products used, and know the date on which the larvae appear, so that insecticide and acaricide use can be rationalised.

Conventional medicine which fights disease by using drugs to counter pathological processes.

Biopiracy describes the practice of stealing the biological resources of a country or people for commercial ends. It is mainly practiced by countries in the Northern Hemisphere to the detriment of those in the Southern Hemisphere, by patenting genes or species so that the patent-holders exclusively benefit from sale of the products concerned and their derivatives.

Certain plants produce semiochemical compounds, i.e. substances that induce some physiological or behavioural response in individuals of a given species or different species. In this case, the activity targets insect pests. Products for human use are usually referred to as biocidal (e.g. anti-lice shampoos, insecticide lotions, etc.) whereas the word insecticide is usually used for products used on plants.

Neem oil is obtained by simple cold-pressing of neem seeds without any purification, in contrast to azadirachtin extract (i.e. the essential oil) which is generated by distillation and aqueous or organic extraction, resulting in a far higher concentration of the active substance.

This is the same as cold-pressing but the seed homogenate is heated before pressing which, after filtration, yields a crude oil that contains more of the active substances but at lower concentrations.

The insecticide is carried in the treated plant's sap after spraying (or injection in silviculture). This mode of treatment is particularly effective against insects that feed on the plant's sap (mealy bugs, aphids, etc.).

About the Neem

In Brazil, all the fruit and vegetable producers but also all the distributors of farm products know the neem. Since 2001, we use it frequently to cure the animals and for the agriculture.
More infos...

The biologic alternative

The azadirachtin extract contained in the neem’seeds was very efficient against the larva that were destroying the foliages, against 13 species of lepidopterous insects and against sawflies.
More infos

Did you know?

When the tree reaches maturity, it can produce until 50Kg of fruits what is equivalent to 30Kg of seeds. These ones constitute the main source of components with some insecticidal properties as the azadirachtin. However, the quantity of azadirachtin contained in the seeds considerably changes according to the climatic conditions, the soil conditions and the genotype of the tree (Ermel 1986 ; Singh 1986).