Molecular Identification and Phylogenetic Analysis of a Group 16SrI-B Phytoplasma Associated with Sugarcane Yellow Leaf Syndrome in Brazil

Yellow leaf syndrome was a serious problem in the beginning of the 1990s in Brazil, when yield losses were estimated to be around 50%. The disease is currently endemic, but it is considered potentially important. Previous studies have revealed only the presence of a luteovirus associated with the disease in Brazil. We report that a phytoplasma of 16SrI-B is also associated with this disease. This is the first demonstration of the presence of a group 16SrI-B phytoplasma in association with sugarcane yellow leaf in Brazil.

Molecular and morphological markers for rapid distinction between 2 Colletotrichum species

Endophytic microorganisms reside asymptomatically within plants and are a source of new bioactive products for use in medicine, agriculture, and industry. Colletotrichum (teleomorph Glomerella) is a fungus widely cited in the literature as a producer of antimicrobial substances. Identification at the species level, however, has been a problem in this type of study. Several authors have reported the presence of endophytic fungi from the medicinal plant Maytenus ilicifolia (espinheira-santa) in Brazil that has antimicrobial activity against various pathogens. Therefore, Colletotrichum strains were isolated from M. ilicifolia and identified based on morphology, RAPD markers, sequence data of the internal transcribed spacer regions (ITS-1 and ITS-2), the 5.8S gene, and species-specific PCR. The analyses suggested the presence of 2 species, Colletotrichum gloeosporioides and Colletotrichum boninense. Two morphological markers were characterized to allow C. gloeosporioides and C. boninense to be distinguished quickly and accurately. The molecular diagnosis of C. boninense was confirmed by using Coll and ITS4 primers. This species of Colletotrichum is reported for the first time in M. ilicifolia.

Occurrence of phytoplasma associated with sugarcane yellow leaf syndrome in three regions of Sao Paulo State, Brazil

Sugarcane yellow leaf syndrome caused serious damage to crops in the Sao Paulo State, Brazil, in the 1990`s. The syndrome was also reported in other countries and investigations into the etiology revealed an association between the disease and virus and/or phytoplasma. The disease is potentially important and occurs endemically in that State, and for this reason the present study was conducted in order to demonstrate the occurrence of phytoplasma in three traditional sugarcane-producing areas, in Sao Paulo State, through molecular detection From naturally infected plants. Symptomatic plants belonging to varieties SP71-6163, SP71-6180 and SP89-1115 were sampled from Piracicaba, Jau and Ribeirao Preto, and total DNA was extracted from foliar tissues. Nested PCR was conducted with primer pairs P1/ Tint-16F2n/R2, and the amplified products were analyzed by electrophoresis on agarose gels. Amplified DNA fragments of 1.2 kb evidenced the presence of phytoplasma in 36% of symptomatic plants and revealed its Occurrence in all sampled regions. The results demonstrated that phytoplasma is associated with the disease and that it is important to keep a safe inspection of nurseries and monitoring plants in the field, as well as to Select Sugarcane genotypes with a good level of resistance in breeding programs.

Genetic variability among sugarcane genotypes based on polymorphisms in sucrose metabolism and drought tolerance genes

Target region amplification polymorphism (TRAP) markers were used to estimate the genetic similarity (GS) among 53 sugarcane varieties and five species of the Saccharum complex. Seven fixed primers designed from candidate genes involved in sucrose metabolism and three from those involved in drought response metabolism were used in combination with three arbitrary primers. The clustering of the genotypes for sucrose metabolism and drought response were similar, but the GS based on Jaccard`s coefficient changed. The GS based on polymorphism in sucrose genes estimated in a set of 46 Brazilian varieties, all of which belong to the three Brazilian breeding programs, ranged from 0.52 to 0.9, and that based on drought data ranged from 0.44 to 0.95. The results suggest that genetic variability in the evaluated genes was lower in the sucrose metabolism genes than in the drought response metabolism ones.

Genetic variability in S(1) families from different maize populations.

Genetic variability in S(1) families from different maize populations. The objectives of the present work were directed towards the study of genetic: variablilty In seven maize populations with a broad genetic base, as a guide for population improvement. The field evaluation was conducted in completely randomized blocks, at one location (Anhembi, Sao Paulo state) with different groups, of S(1) families Obtained from seven populations (GO-D: dent type, GO-F: flint type, GO-L: long car, GO-G: thick Car; and composites G3, G4 and GO-S). Estimates were obtained for genetic variance (progeny mean basis), phenotypic variance of families means, and coefficient of heritability (broad sense) for progeny means. Estimates of heritability were high for Car weight (0,89 to 0.94), car length (0.77 to 0.88) and car diameter (0.77 to 0.92); and lower for plant height (0.58 to 0.80) and Car height (0.54 to 0.84), thus showing the high Potential of the populations for recurrent selection based oil S, families. Ear yield in the base populations used as controls varied front 11,200 kg ha(-1) (GO-D) to 12,800 kg ha(-1) (G3). The means of S(1) families varied from 6,070 kg ha(-1) (GO-F) to 7,380 kg ha(-1) (G4); the Inbreeding depression in S(1) Families varied front 37.5% (G4) to 48.0% (G3) relative to the non-inbred population.

Effects of the herbicides acetochlor and metolachlor on antioxidant enzymes in soil bacteria

The aim of this study was to investigate the antioxidant responses of three bacteria (SD1. KD and K9) isolated from soil previously treated with the herbicides metolachlor and acetochlor. By 165 rRNA gene sequencing, we determined that SD1 is phylogenetically related to Enterobacter asburiae, while KD and K9 have divergent genomes that more closely resemble that of Enterobacter amnigenus. Decreased levels of lipid peroxidation were observed in SD1 and KD following treatment with 34 mM metolachlor or 62 mM acetochlor, respectively, indicating that both bacteria were able to adapt to an increase in ROS production. In the presence of 34 mM metolachlor or 62 mM acetochlor, all bacterial isolates exhibited increases in total catalase (CAT) activity (81% for SDI, 53% for KD and 59% for K9), whereas total SOD activity (assessed based on the profile and intensity of the bands) was slightly reduced when the bacteria were exposed to high concentrations of the herbicides (340 mM metolachlor or 620 mM acetochlor). This effect was due to a specific reduction in SOD IV (K9 and KD isolates) by 45% and 90%, respectively, and SOD V (SD1 isolate) isoenzymes by 60%. The most striking result was obtained in the SD1 isolate, where two novel isoenzymes of glutathione reductase (GR) that responded specifically to metolachlor were identified. In addition, acetochlor was shown to induce the expression of a new 57 kDa protein band in the K9 and KD isolates. The bacteria isolated from the herbicide-contaminated soil exhibited an efficient antioxidant system response at herbicide concentrations of up to 34 mM metolachlor or 62 mM acetochlor. These data suggest a mechanism for tolerance that may include the control of an imbalance in ROS production versus scavenging. The data suggest that specific isoenzymes of CAT and GR could be involved in this herbicide tolerance mechanism. (C) 2011 Elsevier Ltd. All rights reserved.

Dormancy as exaptation to protect mimetic seeds against deterioration before dispersal

Mimetic seeds simulate the appearance of fleshy fruits and arilled seeds without producing nutritive tissues as a reward for seed dispersers. In this strategy of seed dispersal, seeds may remain attached to the mother plant for long periods after maturity, increasing their availability to naive seed dispersers. The hypothesis that seed coat impermeability in many tropical Fabaceae with mimetic seeds serves as an exaptation to protect the seeds from deterioration and rotting while awaiting dispersal was investigated. Seed coat impermeability was evaluated in five mimetic-seeded species of tropical Fabaceae in south-eastern Brazil (Abarema langsdorffii, Abrus precatorius, Adenanthera pavonina, Erythrina velutina and Ormosia arborea) and in Erythrina speciosa, a `basal` species in its genus, which has monochromatic brown seeds and no mimetic displays. Seed hardness was evaluated as a defence against accelerated ageing (humid chamber at 41 degrees C for 144 h). Seed development and physiological potential of O. arborea was evaluated and the effect of holding mature seeds in pods on the mother plant in the field for a period of 1 year under humid tropical conditions was compared with seeds stored under controlled conditions (15 degrees C and 40 % relative air humidity). All five mimetic-seeded species, and E. speciosa, showed strong coat impermeability, which protected the seeds against deterioration in accelerated ageing. Most O. arborea seeds only became dormant 2 months after pod dehiscence. Germination of seeds after 1 year on the plant in a humid tropical climate was 56 %, compared with 80 % for seeds stored in controlled conditions (15 degrees C, 45 % relative humidity). Seedling shoot length after 1 year did not differ between seed sources. Dormancy acts in mimetic-seeded species as an exaptation to reduce seed deterioration, allowing an increase in their effective dispersal period and mitigating the losses incurred by low removal rates by naive avian frugivores.

The potential for increasing rubber production by matching tapping intensity to leaf area index

Understanding resource capture can help design appropriate species combinations, planting designs and management. Leaf area index (LAI) and its longevity are the most important factors defining dry matter production and thus growth and productivity. The ecophysiological modifications and yield of rubber (Hevea spp.) in an agroforestry system (AFS) with beans (Phaseolus vulgaris L.) were studied. The experiment was established in Southeast-Brazil, with three rubber cultivars: IAN 3087, RRIM 600 and RRIM 527. The AFS comprised double rows of rubber trees along with beans sown in autumn and winter seasons in 1999. There was about 50% higher rubber yield per tree in the AFS than the rubber monoculture. Trees within the AFS responded to higher solar radiation availability with higher LAI and total foliage area, allowing its greater interception. All three cultivars had higher LAI in the AFS than monoculture, reaching maximum values in the AFS between April and May of 3.17 for RRIM 527; 2.83 for RRIM 600 and 2.28 for IAN 3087. The maximum LAI values for monocrop rubber trees were: 2.65, 2.62 and 1.99, respectively, for each cultivar. Rubber production and LAI were positively correlated in both the AFS and monoculture but leaf fall of rubber trees in the AFS was delayed and total phytomass was larger. It is suggested that trees in the AFS were under exploited and could yield more without compromising their life cycle if the tapping system was intensified. This shows how knowledge of LAI can be used to manage tapping intensity in the field, leading to higher rubber yield.

Air trapping: The major factor limiting diaphragm mobility in chronic obstructive pulmonary disease patients

Background and objective: Patients with COPD can have impaired diaphragm mechanics. A new method of assessing the mobility of the diaphragm, using ultrasound, has recently been validated. This study evaluated the relationship between pulmonary function and diaphragm mobility, as well as that between respiratory muscle strength and diaphragm mobility, in COPD patients. Methods: COPD patients with pulmonary hyperinflation (n = 54) and healthy subjects (n = 20) were studied. Patients were tested for pulmonary function, maximal respiratory pressures and diaphragm mobility using ultrasound to measure the craniocaudal displacement of the left branch of the portal vein. Results: COPD patients had less diaphragm mobility than did healthy individuals (36.5 +/- 10.9 mm vs 46.3 +/- 9.5 mm, P = 0.001). In COPD patients, diaphragm mobility correlated strongly with pulmonary function parameters that quantify air trapping (RV: r = -0.60, P < 0.001; RV/TLC: r = -0.76, P < 0.001), moderately with airway obstruction (FEV1: r = 0.55, P < 0.001; airway resistance: r = -0.32, P = 0.02) and weakly with pulmonary hyperinflation (TLC: r = -0.28, P = 0.04). No relationship was observed between diaphragm mobility and respiratory muscle strength (maximal inspiratory pressure: r = -0.11, P = 0.43; maximal expiratory pressure: r = 0.03, P = 0.80). Conclusion: The results of this study suggest that the reduction in diaphragm mobility in COPD patients is mainly due to air trapping and is not influenced by respiratory muscle strength or pulmonary hyperinflation.

Drying and storage of cauliflower (Brassica oleracea var. botrytis) hydroprimed seeds

Literature has documented beneficial effects of seed priming on speed, synchronization and uniformity of germination. often leading to improved stand establishment. However. doubts still persist about the possible reversal effects, after drying and during storage of primed seeds that could overcome, partial or totally, the improved performance. The objectives of this research were to identify drying and storage procedures that would maintain the physiological performance achieved after seed priming, without negative effects on storability. First. hydroprimed cauliflower Seeds cv. Sharon and cv. Teresopolis Gigante, each represented by three seed lots were submitted to fast drying, slow drying, and treatments of pre-drying incubation (exposure to 35 degrees C, to a polyethylene glycol 6000 solution or a heat shock) followed by fast drying. In the second phase of this study, hydroprimed seed samples were submitted to fast drying (30-35 degrees C and 40-50% R.H.) and stored under laboratory conditions or in a chamber at 20 degrees C and 50% relative humidity for six months. Seed physiological potential was evaluated after 60-day intervals for germination (speed and percentage), Seedling emergence and saturated salt accelerated aging tests. All drying treatments efficiently preserved the favourable priming effects, except for the incubation at 35 degrees C for 96-144 hours. The beneficial priming effects followed by fast drying persisted for four months under controlled conditions (20 degrees C and 50% relative humidity).

Landscape unit discrimination for pedological surveys by orbital spectral response

Landscape unit discrimination for pedological surveys by orbital spectral response. The objective of tins study was compare two soil survey methods. The first was performed by methods traditionally used to distinguish landscape units and soil class discrimination. The second was based on soil class distinction through orbital spectral response. In order to establish soil characteristics and their classification, soil samples were collected at two depths in a grid system, with a distance of 500 meters between points. With these samples, physical and chemical analyses were carried out. In the sampling points, the apparent reflectance of the soil, front the orbital image, was determined and, through cluster analysis landscape units were established. In order to evaluate the resemblance reliability between the landscape units established in each method, the Kappa index was used, the value set for the confusion matrix was 0.43, indicating high quality in the comparison, showing that the non-conventional method was as close as the one carried out by photointerpretation.

Sweet Basil (Ocimum basilicum) Extracts Obtained by Supercritical Fluid Extraction (SFE): Global Yields, Chemical Composition, Antioxidant Activity, and Estimation of the Cost of Manufacturing

In this work, supercritical technology was used to obtain extracts from Ocimum basilicum (sweet basil) with CO(2) and the cosolvent H(2)O at 1, 10, and 20% (w/w). The raw material was obtained from hydroponic cultivation. The extract`s global yield isotherms, chemical compositions, antioxidant activity, and cost of manufacturing were determined. The extraction assays were done for pressures of 10 to 30 MPa at 303 to 323 K. The identification of the compounds present in the extracts was made by GC-MS and ESI-MS. The antioxidant activity of extracts was determined using the coupled reaction of beta-carotene and linolenic acid. At 1% of cosolvent, the largest global yield was obtained at 10 MPa and 303 K (2%, dry basis-d.b.); at 10% of cosolvent the largest global yield was obtained at 10 and 15 MPa (11%, d.b.), and at 20% of cosolvent the largest global yield was detected at 30 MPa and 303 K (24%, d.b.). The main components identified in the extracts were eugenol, germacrene-D, epi-alpha-cadinol, malic acid, tartaric acid, ramnose, caffeic acid, quinic acid, kaempferol, caffeoylquinic acid, and kaempferol 3-O-glucoside. Sweet basil extracts exhibited high antioxidant activity compared to beta-carotene. Three types of SFE extracts from sweet basil were produced, for which the estimated cost of manufacturing (class 5 type) varied from US$ 47.96 to US$ 1,049.58 per kilogram of dry extract.

Ovarian function in cows submitted to acute stress during proestrus

Studies in which ACTH was administrated in heifers after the occurrence of luteolysis showed a delay in the onset of estrus and the estrus duration was shortened. This study evaluated the effect of acute stress by road transportation on estrous behavior and ovulation, monitored by serum progesterone and cortisol concentrations in cows at the periovulatory period, using a crossover design. Eleven crossbred cows, divided into Control and Transport groups had their estrus cycle synchronized with GnRH, an intravaginal progesterone device, and cloprostenol. Thirty hours after withdrawal of the device, the animals of the Transport group were transported for 60 min by truck and those from the Control group remained at pasture. Ovarian ultrasound examination was performed every 12 h from device withdrawal until ovulation in every cow. From the day after removal of the device until ovulation estrous behavior was monitored 24 h a day. Blood samples for serum cortisol and progesterone concentrations were taken at -90, -60, 0, 30, 60 and 180 min in relation to the end of transportation. Transportation during the estrous period induced stress in cows as reflected by changes in serum concentrations of progesterone and cortisol. However, we did not detect impairment in estrus expression, estrus duration or ovulation (P>0.05). (C) 2010 Elsevier B.V. All rights reserved.

DOSES OF INDOLBUTYRIC ACID IN THE ROOTING AND GROWTH OF EUCALYPT CUTTINGS (Eucalyptus urophylla)

This work aimed to evaluate the effect of different concentrations of IBA (indolbutyric acid) in the rooting and growth of Eucalyptus urophylla cuttings. The experimental design used was the randomized blocks, in factorial with an arrangement of split plots, with three concentrations of IBA (2.000; 5.000 and 8.000 mg L(-1)), two ways of the application of plant gowth regulators (paste and powder), and three period of evaluations (30, 45 and 60 days). The experiment was carried out in the Farm Buriti de Prata, an entreprise property of Souza Cruz, in the city of Prata - MG in 2003. After the preparation of the cuttings, patterned in 10 cm of length and 0.8 cm of diameter, those were immersed in mixtures of IBA for 10 seconds, in the forms of dry powder and paste and than planted in plastic tubes contening Plantmax substrate with vermiculite. The cuttings were transported to greenhouse with controled humidity, where they remained for 60 days. The variables studied were: height of plant in the 30(th), 45(th) and 60(th) days after seeding; fresh mass of the aerial part and roots. The IBA applied in powder form as well as in paste form, resulted in an greater seedling growth. To the 60 days, the seedlings presented greater growth, being significantly superior to the heights measured in other times of evaluation. The application of 2.000 mg L(-1) and 5,000 mg L(-1) resulted in significant increases on weight of fresh mass of the aerial part and root system.