Banca de DEFESA: RAFAEL SILVA SOBRAL

Uma banca de DEFESA de MESTRADO foi cadastrada pelo programa.
STUDENT : RAFAEL SILVA SOBRAL
DATE: 22/03/2021
TIME: 14:00
LOCAL: online
TITLE:

 P accumulation in two Thitonia  species under different sources of phosphate

KEY WORDS:

Green manure, Thitonia diversifolia, phosphorus.

PAGES: 62
BIG AREA: Ciências Agrárias
AREA: Agronomia
SUBÁREA: Ciência do Solo
SPECIALTY: Fertilidade do Solo e Adubação
SUMMARY:

Phosphorus deficiency is widespread in most tropical agroecosystems due to specific adsorption reactions, phosphorus interaction with the minerals of these soils. Some plant species can exude substances from the roots that solubilize poorly soluble phosphorous sources, increasing the efficiency of phosphate fertilization. Tithonia diversifolia is a widely used species in agroforestry systems. It has been assumed to accumulate P even under low P soils. This research aims to evaluate whether Thitonia diversifolia and Tithonia rotundifolia can absorb phosphorus from less available P pools.  Zea mays, a P demanding plant, and Cajanus cajan, adapted to low levels of soil P, were used as references. A study was carried out in a greenhouse, in pots containing soil with low P content, with the following species: Tithonia diversifolia, Tithonia rotundifolia, Cajanus cajan, and Zea mays. The treatments consisted of zero, 60, 90, and 120 kg ha-1 of P2O5 from simple superphosphate and Yoorin thermophosphate. Two subsequent crops were carried out in 16L pots for 210 days. The plants were evaluated for the content and total accumulation of P in the aerial part. The results showed higher levels of P in the biomass of the aerial part of the two species of Tithonia without, however, having evidenced the use of less soluble sources. The cultivation of these two species resulted in higher levels of labile P in the soil. However, there was no decrease in the P stock of the less labile fractions during the experiment period.

 

 

 

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