Selection,characterization and genetic analysis of laboratory mutants of <Emphasis Type="Italic">Botryotinia fuckeliana</Emphasis> (<Emphasis Type="Italic">Botrytis cinerea</Emphasis>) resistant to the fungicide boscalid

Resistance to the fungicide boscalid in laboratory mutants of Botryotinia fuckeliana (Botrytis cinerea) was investigated. The baseline sensitivity to boscalid was evaluated in terms of colony growth (EC₅₀ = 0.3–3 μg ml⁻¹; MIC = 10–30 μg ml⁻¹) and conidial germination (EC₅₀ = 0.03–0.1 μg ml⁻¹; MIC = 1–3 μg ml⁻¹) tests. Mutants were selected in vitro from wild-type strains of the fungus on a fungicide-amended medium containing acetate as a carbon source. Mutants showed two different levels of resistance to boscalid, distinguishable through the conidial germination tests: low (EC₅₀ ∼ 0.3 μg ml⁻¹, ranging from 0.03 to 1 μg ml⁻¹; MIC > 100 μg ml⁻¹) and high (EC₅₀ > 100 μg ml⁻¹) resistance. Analysis of meiotic progeny from crosses between resistant mutants and sensitive reference strains showed that resistant phenotypes were due to mutations in single major gene(s) inherited in a Mendelian fashion, and linked with both the Daf1 and Mbc1 genes, responsible for resistance to dicarboximide and benzimidazole fungicides, respectively. Gene sequence analysis of the four sub-units of the boscalid-target protein, the succinate dehydrogenase enzyme, revealed that single or double point mutations in the highly conserved regions of the iron-sulphur protein (Ip) gene were associated with resistance. Mutations resulted in proline to leucine or phenylalanine replacements at position 225 (P225L or P225F) in high resistant mutants, and in a histidine to tyrosine replacement at position 272 (H272Y) in low resistant mutants. Sequences of the flavoprotein and the two transmembrane sub-units of succinate dehydrogenase were never affected.     

Effects of crude seed extracts of Annona atemoya and Annona squamosa L. against the cabbage looper, Trichoplusia ni in the laboratory and greenhouse

Antifeedant, growth inhibitory and toxic effects of crude seed extracts of Annona squamosa and Annona atemoya from Fazenda Viveiro Bona, Parasisópolis – Minas Gerais, Brazil, were evaluated against the cabbage looper, Trichoplusia ni (Hübner) (Lepidoptera: Noctuidae) using different bioassays. Crude methanolic seed extracts deterred feeding of third instar T. ni larvae in a leaf disc choice bioassay. A. squamosa was ∼10 times more active as a feeding deterrent than A. atemoya (DC₅₀ = 2.3 mg/ml vs. 20.1 mg/ml). A. squamosa was ∼three times more active as a growth inhibitor than A. atemoya (EC₅₀ = 38.0 ppm vs. 117.0 ppm). Methanolic seed extracts of A. squamosa and A. atemoya were toxic to third instar T. ni larvae both through topical and oral application. A. squamosa was more toxic through feeding (LC₅₀ = 167.5 ppm vs. 382.4 ppm) whereas, A. atemoya exerted greater toxicity via topical application (LC₅₀ = 301.3 μg/larva vs. 197.7 μg/larva). Both A. squamosa and A. atemoya extracts reduced leaf area consumption and larval growth in a greenhouse experiment. Our results indicate that both A. squamosa and A. atemoya have potential for development as botanical insecticides, especially for local use in Brazil.     

A rapid staining‐assisted wood sampling method for PCR‐based detection of pine wood nematode Bursaphelenchus xylophilus in Pinus massoniana wood tissue

For reasons of unequal distribution of more than one nematode species in wood, and limited availability of wood samples required for the PCR‐based method for detecting pinewood nematodes in wood tissue of Pinus massoniana, a rapid staining‐assisted wood sampling method aiding PCR‐based detection of the pine wood nematode Bursaphelenchus xylophilus (Bx) in small wood samples of P. massoniana was developed in this study. This comprised a series of new techniques: sampling, mass estimations of nematodes using staining techniques, and lowest limit Bx nematode mass determination for PCR detection. The procedure was undertaken on three adjoining 5‐mg wood cross‐sections, of 0.5 × 0.5 × 0.015 cm dimension, that were cut from a wood sample of 0.5 × 0.5 × 0.5 cm initially, then the larger wood sample was stained by acid fuchsin, from which two 5‐mg wood cross‐sections (that adjoined the three 5‐mg wood cross‐sections, mentioned above) were cut. Nematode‐staining‐spots (NSSs) in each of the two stained sections were counted under a microscope at 100× magnification. If there were eight or more NSSs present, the adjoining three sections were used for PCR assays. The B. xylophilus– specific amplicon of 403 bp ( DQ855275 ) was generated by PCR assay from 100.00% of 5‐mg wood cross‐sections that contained more than eight Bx NSSs by the PCR assay. The entire sampling procedure took only 10 min indicating that it is suitable for the fast estimation of nematode numbers in the wood of P. massonina as the prelimary sample selections for other more expensive Bx‐detection methods such as PCR assay.     

Participatory organic certification in Mexico: an alternative approach to maintaining the integrity of the organic label

Over the past two decades the growth of the organic sector has been accompanied by a shift away from first party, or peer review, systems of certification and towards third party certification, in which a disinterested party is responsible for the development of organic standards and the verification of producer compliance. This paper explores some of the limitations of the third party certification model and presents the case of Mexico as an example of how an alternative form of participatory certification has emerged. The paper suggests that participatory guarantee systems (PGS) are reflective of the growing “beyond organic” movement, which focuses on reconstructing the local and re-embedding food systems into their socio-ecological contexts. It argues that PGS offers a number of benefits for producers and consumers, particularly in the South, but that it faces a number of challenges as well, such as a lack of formal recognition, social conflicts and dependence on donated resources.     

SHORT COMMUNICATION: Normal aerobic bacterial conjunctival flora in the Crab‐eating raccoon (Procyon cancrivorus) and Coati (Nasua nasua) housed in captivity in pernambuco and paraiba (Northeast,Brazil)

Objective To determine the normal aerobic bacterial conjunctival population of the Coatis and the Crab‐eating raccoons housed in captivity in the Pernambuco and Paraiba states of Brazil. Animals studied Ten healthy Coatis and 10 healthy Crab‐eating raccoons were selected for this study. Animals are from three zoos situated at the Pernambuco and Paraiba States in the north‐east of Brazil. Procedures After ophthalmologic examination, swabs from healthy animals were carefully collected in order to avoid contamination. Samples were identified and submitted to the laboratory. Swabs were plated for culture on ovine blood agar (8%) and agar Levine and incubated at 37 °C and observed 24 and 48 h. Results Staphylococcus spp. was the most common microorganism isolated from conjunctival sac. Shigella spp. comprised the Gram‐negative genera isolated. Escherichia coli were isolated from the right eye of one Coati that had no growth at contralateral eye. Nine eyes from coatis and 10 from Crab‐eating raccoons had no microorganisms isolated. Conclusion Our results were in accordance with previous studies indicating Staphylococcus sp., followed by Corynebacterium spp. as the most common inhabitant of the eyes of most mammalian species.     

Hypotensive action of naturally occurring diterpenes: A therapeutic promise for the treatment of hypertension

Plants have always been an exemplary source of drugs and many of the currently available medicines have been directly or indirectly derived from them. For this reason, the research, development and use of natural products as therapeutic agents, especially those derived from plants, have been increasing in recent years. A great deal of attention has focused on the naturally occurring antispasmodic phytochemicals as potential drugs for the treatment of cardiovascular diseases. Arterial hypertension is a common and progressive disorder that poses a major risk for cardiovascular and renal diseases. Recent data have revealed that the global burden of hypertension is an important and increasing public health problem worldwide and that the level of awareness, treatment and control of hypertension varies considerably among countries. The research on naturally occurring blood pressure-lowering agents is rapidly expanding due to the high potential of such molecules as new antihypertensive drugs. Recently, a great number of plant-derived substances, such as diterpenoids, have been evaluated as possible antihypertensive agents. Naturally occurring diterpenes such as forskolin and stevioside, exhibit vasorelaxant action and inhibit vascular contractility by different mechanisms of action. In this review we will discuss the mechanisms underlying the hypotensive action displayed by diterpenes and their potential use in human hypertension. We will also discuss the use of these compounds in the treatment of glaucoma, which is characterized by increased intraocular pressure (IOP).     

Antioxidants profile of small tomato fruits: Effect of irrigation and industrial process

Carotenoids and flavonoids are the main tomatoes antioxidants, having an important role for human health. This study investigates the effects of different water regime and of the industrial processing on the concentration of these compounds in tomato fruits and in tomato products. Two biotypes of Corbarini small tomatoes were cultivated in the Sarno valley (Salerno, Italy) using three different water regimes. A biochemical characterization of the fresh and of the corresponding canned products was performed. Results show that water regime influenced the antioxidant profile of tomato fruits, with marked differences between the two biotypes. Data obtained highlight that water regime markedly influenced the productivity and the quality of the tomatoes. Results also demonstrated that industrial process increased carotenoids content without causing a significant flavonoids degradation.