Influência da adubação fosfatada sobre o crescimento do camapu (Physalis angulata L.)

Abstract

RESUMO:A espécie Physalis angulata L., pertencente à família Solanaceae, tem despontado como uma planta extremamente promissora para uso medicinal, em razão da produção do composto fisalina. No entanto, aspectos importantes do seu cultivo ainda permanecem pouco conhecidos. Assim, objetivou-se avaliar a influencia do fósforo para o seu crescimento. O experimento foi conduzido em Latossolo Amarelo de textura média, submetido a três doses de P: 8, 16 e 64 mg kg . Sob deficiência, a produção da massa seca total foi de apenas 1,72g, enquanto para a dose de 64 mg kg -1 de P no solo esse valor foi de 7,58g, significando um aumento de 340%. Plantas cultivadas com 8 mg kg -1 de P no solo não apresentaram flores ou frutos; já para o tratamento em que se utilizou 64 mg kg -1 de P no solo, o início do florescimento antecedeu ao das plantas cultivadas com 16 mg kg -1 de P no solo. A razão de área foliar e a área foliar específica foram maiores para as plantas cultivadas sob deficiência, enquanto a taxa de crescimento relativo e a taxa assimilatória líquida não foram estatisticamente influenciadas. Conclui-se que a deficiência de P no solo pode comprometer sobremaneira o crescimento das plantas de Physalis. Além disso, como a deficiência de P reduziu sensivelmente a produção de folhas, órgão responsável pela produção da fisalina, também é possível concluir que a deficiência de P pode, mesmo que indiretamente, reduzir a concentração desse importante composto na planta. Palavras-chave:Physalis angulata, taxa de crescimento, produção de massa seca, adubação fosfatada. ABSTRACT: Influence of phosphorus fertilization over the growth of the camapu (Physalis angulata L.).The specie Physalis angulata L., who belongs to the Solanaceae family, has stand out as an extremely promising plant in terms of medical use, due to the production of the physalin compound. However, important aspects of its production still remain unknown. Thus the objective of this work was to assess the influence of phosphorus for the growth of these species. The experiment was performed with three doses of P (8, 16 e 64 mg kg -1 de P), in a completely randomized experimental design. Two harvests were performed: at 30 and 42 days after planting. The deficiency of P reduced the number of leaves and leaf area. The total dry matter (DM), as well as a MS from all parts of the plant, was significantly higher for plants grown under the highest levels of phosphorus. Plants grown with 8 mg P kg -1 showed no flowers or fruit; but, for the treatment which used 64 mg of P kg -1 the beginning of flowering happened before than with the plants grown with 16mg. The ratio of the leaf area and the specific leaf area were higher for plants grown under stress, while the values of the relative growth rate and the net assimilatory rate were not statistically influenced. We conclude that the deficiency of P in soil may considerably affect the growth of Physalis plants. Moreover, since the deficiency of P significantly reduced the leaf production, which is responsible for creating the p...

Mineralogy and Maximum Phosphorus Adsorption Capacity in Soybean Development

“…This is a 70% increase due to the P fertilization. This way, in agreement to other investigations (Zhang et al, 2010;Cruz, Souza Filho, & Pelacani, 2015), soils with low P availability provide lower number of flowers and a higher pod abortion, compromising productivity. In this sense, Batistella Filho, Ferreira, Vieira, and Cruz (2013) also obtained a linear response for soybean pod production in Typic Haplortox up to the maximum test dose of 160 kg ha -1 of P 2 O 5 .…”

Hydroponic cultivation of Physalis angulata L.: growth and production under nitrogen doses1

“…Cruz et al (2015) reported a linear behavior for this variable, when assessing the influence of phosphorous on P. angulata growth, observing an absolute growth rate of 0.47 g day -1 at the highest dose of P (64 mg kg ) occurring at an estimated dose of 150 mg L -1 of N (Figure 2f). The relative growth rate curve exhibited similar behavior to that of leaf area ratio and the morphological component of leaf area ratio.…”

“…However, just a few researches have investigated its cultivation or management, including Souza & Amorim (2009), who assessed the growth and development of the species under water deficit, and Cruz et al (2015), who evaluated the influence of phosphate fertilizer on its cultivation. Nevertheless, much needs to be studied to establish cash crops of the species, particularly in terms of mineral nutrition.…”

Gas exchange and chlorophyll content in tomato grown under different organic fertilizers and biofertilizer doses

“…On the other hand, the reduction of root-shoot ratio observed in plants cultivated on manure substrates and high doses of biofertilizer may mean that these plants, once the needs of the root growth have been satisfied by the greater absorption of the nutrients provided by the biofertilization, have passed; they direct their activities to the formation of the aerial part, such as leaves and fruits (Oliveira et al, 2014;Cruz et al, 2015;Kalbani et al, 2016).…”