Florin Crista, Florin Sala, Isidora Radulov, Laura Crista
The paper showed that fertilizers doses used in order to obtain maximum or economical optimal productions vary between large limits from one year to another based on climatic condition. The crop obtain from studied hybrids varied based on mineral fertilizer doses used on area unit from 10000 kg grains per hectare up to 14000 kg grains per hectare. The fertilizers increase obvious the level and the quality of the crops, if they are used rational. The crop profit value must cover the established expenses of their secure and application and to bring profit. The fertilizer’s price increased a lot in the last years, because these are being obtained with high energy consume, that’s why is very important the administration process of production in order to obtain maximum efficiency.  The decisions concerning the quantities of fertilizer and the application way, depends of the following factors: - The specific consume of nutritive elements of the cultivated plants; - The state of supplying the soil with nutritive solutions indispensable to the plants; - The agricultural system (crop rotation); - The agro-technical measures used; - The remains of the fertilizer applied in the former year; - The moment and the way of application for the current year; - The fertilizer’s nature and the economical restrictive factors; The main issue of fertilizers use is to maximize their efficiency per active substance unit. Efficiency implies the ratio of nitrogen in fertilizers which are recuperated from crop boost and, on the other hand, efficiency refers to the quantity of main product which is obtaining from active substance unit. Efficiency can be increased by loses control and removal which appear without doubt on various manners. The quantities of fertilizers entirely used depend of soil wealth in nutritive elements, plant specific consumption, crop rotations, last year’s precipitation, and also of the intensity of diseases and pests.
hybrid; fertilization; maize; crop
Presentation: oral