Anacleto Ranulfo dos Santos

Efeito das interações entre os íons amônio e nitrato na fisiologia do crescimento do amendoinzeiro

Peanut is a crop of great importance for the Northeast region, as it is usually grown by small farmers, who on average, do not exceed 10 ha of cultivated area and aim to increase its profitability and diversify the production. This study aimed to evaluate the effect of the relationship between nitrogen forms (ammonium and nitrate) in the initial growth of peanuts. Complete nutrient solution was used with a single concentration of 210 mg N L-1 provided in five proportions of NH4+:NO3-: 100:0, 75:25, 50:50, 25:75 and 0:100. The experimental units were arranged in completely randomized design, with four replications. The variables evaluated were: shoot length, root length, leaf number, stem diameter, fresh and dry shoot and fresh weight and dry root. The 100:0, 75:25 and 50:50 ratio resulted in decreasing peanut phytomass by ammonium toxicity. However, the 0:100 ratio, nitrate caused a smaller decreased compared to reductions in the highest ammonium concentrations. In the 25:75 and 0:100 ratio, plants grow normally with higher phytomass. The supply of nitrogen in the NH4+ form only is not a good option for the nutrition of peanuts in early growth stages.

LIGHT ENVIRONMENTS AND PHOSPHORUS DOSES IN THE GROWTH OF BASIL PLANTS

The objective of this work was to evaluate the development of basil plants cultivated in modified light environments with the use of color shading nets under different dosages of phosphate fertilization. The experimental design was a randomized block factorial design 4 x 3, with the treatments: 0, 50; 100 and 200 kg ha-1 P2O5 using shading nets in colors: blue and red, with 50% shading and full sun, and five replications. After 120 days of cultivation, analyzes of the growth of basil plants were carried out, in addition to the phosphorus content in the roots. There was a significant interaction between phosphorus doses and light environments for the number of leaves, leaf area, specific leaf area, leaf area ratio and leaf weight ratio. Basil plants grown in full sun at the maximum phosphorus dosage (200 kg ha-1 P2O5) showed significantly higher results than those grown under shade. However, it is worth noting that the shaded environment provided higher height and dry mass production, in addition to higher phosphorus levels in the roots. It was concluded that the interaction of color shading nets with the phosphate fertilization presented positive results in relation to the development of the basil plants.

Metabólitos secundários e características anatômicas de folhas de orégano (Origanum vulgare ssp. hirtum) cultivado sob malhas coloridas

Oreganos plants were grown in different light environments, obtained with the use of colorful fabrics, in order to evaluate the content and composition of essential oil and anatomical characteristics in leaves of these plants. For this, the plants were grown in pots with capacity for 3 dm³ submitted to the following treatments: cultivation under full sun (absolute witness), shading with blue, red and gray colors. It was adopted the DIC with six repetitions. Anatomical features were evaluated of petiole and leaf, content and composition of essential oil. It is observed that modification in the light environment allows increasing the content of essential oil and it influences in the chemical composition of this secondary metabolite.