LEAF TOTAL NITROGEN CONCENTRATION AS AN INDICATOR OF NITROGEN STATUS FOR PLANTLETS AND YOUNG PLANTS OF EUCALYPTUS CLONES

The use of leaf total nitrogen concentration as an indicator for nutritional diagnosis has some limitations. The objective of this study was to determine the reliability of total N concentration as an indicator of N status for eucalyptus clones, and to compare it with alternative indicators. A greenhouse experiment was carried out in a randomized complete block design in a 2 × 6 factorial arrangement with plantlets of two eucalyptus clones (140 days old) and six levels of N in the nutrient solution. In addition, a field experiment was carried out in a completely randomized design in a 2 × 2 × 2 × 3 factorial arrangement, consisting of two seasons, two regions, two young clones (approximately two years old), and three positions of crown leaf sampling. The field areas (regions) had contrasting soil physical and chemical properties, and their soil contents for total N, NH+4-N, and NO−3-N were determined in five soil layers, up to a depth of 1.0 m. We evaluated the following indicators of plant N status in roots and leaves: contents of total N, NH+4-N, NO−3-N, and chlorophyll; N/P ratio; and chlorophyll meter readings on the leaves. Ammonium (root) and NO−3-N (root and leaf) efficiently predicted N requirements for eucalyptus plantlets in the greenhouse. Similarly, leaf N/P, chlorophyll values, and chlorophyll meter readings provided good results in the greenhouse. However, leaf N/P did not reflect the soil N status, and the use of the chlorophyll meter could not be generalized for different genotypes. Leaf total N concentration is not an ideal indicator, but it and the chlorophyll levels best represent the soil N status for young eucalyptus clones under field conditions

Influence of the N/K ratio on the production and quality of cucumber in hydroponic system

The objective of this work was to evaluate the quality of fruits and the nutritional status of cucumber CV. Aodai cultivated in nutrient solutions with different N:K ratios. The hydroponic cultivation was initially performed, during the vegetative growth, in nutrient solution with 1:2.0 mmol L-1 N:K, and, later, during fruit setting, in four different nutrient solutions with N:K (w/w) at the ratios 1:1.4, 1:1.7, 1:2.0 and 1:2.5. An additional treatment with a nutrient solution containing the ratio 1:2.2 (w/w) N:K during the vegetative growth and N:K 1:1.4 (w/w) during fruit setting, both with 10% ammonium (NH4+) was included. The treatments were arranged in a randomized design with six replicates. Irrigation was carried out with deionized water until seed germination, and then with nutrient solution until 30 days after germination, when plants were transplanted. Plants in the hydroponic growing beds were irrigated with the solutions for vegetative growth, and, after 21 days, the solutions were replaced by solutions for fruit setting. At 45 and 60 days after transplanting, the fresh weight, length, diameter, volume and firmness of the fruit were evaluated, and, at 45 days after transplanting, the macronutrient concentrations in the leaves were determined. The use of different N:K ratios during fruit setting influenced the cucumber production. The ratio of 1.0:1.7 N: K (w/w), with 10% of N in the form of ammonia, is recommended for the whole cycle

Influence of tinnitus on pain severity and quality of life in patients with temporomandibular disorders

OBJECTIVE: The aim of this cross-sectional study was to evaluate the relationship among pain intensity and duration, presence of tinnitus and quality of life in patients with chronic temporomandibular disorders (TMD). MATERIAL AND METHODS: Fifty-nine female patients presenting with chronic TMD were selected from those seeking for treatment at the Bauru School of Dentistry Orofacial Pain Center. Patients were submitted to the Research Diagnostic Criteria anamnesis and physical examination. Visual analog scale was used to evaluate the pain intensity while pain duration was assessed by interview. Oral Health Impact Profile inventory modified for patients with orofacial pain was used to evaluate the patients' quality of life. The presence of tinnitus was assessed by self report. The patients were divided into: with or without self report of tinnitus. The data were analyzed statistically using the Student's t-test and Pearson's Chi-square test, with a level of significance of 5%. RESULTS: The mean age for the sample was 35.25 years, without statistically significant difference between groups. Thirty-two patients (54.24%) reported the presence of tinnitus. The mean pain intensity by visual analog scale was 77.10 and 73.74 for the groups with and without tinnitus, respectively. The mean pain duration was 76.12 months and 65.11 months for the groups with and without tinnitus, respectively. The mean OHIP score was 11.72 and 11.74 for the groups with and without tinnitus, respectively. There was no statistically significant difference between groups for pain intensity, pain duration and OHIP scoreS (p>0.05). CONCLUSION: Chronic TMD pain seems to play a more significant role in patient's quality of life than the presence of tinnitus