Achado o ponto fraco da vassoura de bruxa

127
Descoberta abre caminho para o desenvolvimento de drogas capazes de matar a principal praga que afeta a produção de cacau no país. Doença derrubou produção de cacau no Brasil (divulgação)
 Achado o ponto fraco da vassoura de bruxa
Por Karina Toledo
Agência FAPESP – A estratégia usada pela praga vassoura-de-bruxa – principal doença que afeta a produção de cacau no país – para resistir ao ataque da planta hospedeira e aos mais potentes fungicidas do mercado foi desvendada por pesquisadores da Universidade Estadual de Campinas (Unicamp).
A descoberta, publicada na revista New Phytologist, abre caminho para o desenvolvimento de novas drogas capazes de combater a doença de forma efetiva.
Causada pelo fungo Moniliophthora perniciosa, a vassoura-de-bruxa tem esse nome porque deixa os ramos do cacaueiro secos como uma vassoura velha. As áreas afetadas não conseguem realizar fotossíntese e, para piorar, liberam substâncias tóxicas que diminuem a produção de frutos. Os poucos frutos produzidos se tornam inviáveis para a fabricação de chocolate.
“Na fase inicial da infecção, a planta tenta deter a ação do invasor liberando grandes quantidades de óxido nítrico (NO), substância capaz de bloquear a cadeia respiratória do fungo. Mas descobrimos que a vassoura-de-bruxa possui um mecanismo alternativo de respiração que lhe permite resistir a esse ataque”, explicou Gonçalo Amarante Guimarães Pereira, coordenador do Laboratório de Genômica e Expressão da Unicamp, onde a pesquisa foi conduzida.
Ironicamente, a própria planta acaba sofrendo os efeitos tóxicos do NO. Os galhos infectados morrem e viram banquete para a M. perniciosa. “O fungo tem uma fase biotrófica, na qual vive dentro da planta ainda viva, e outra necrotrófica, em que se alimenta do tecido morto”, disse Pereira.
A equipe coordenada pelo pesquisador descobriu que, durante a fase biotrófica, quando está sob o ataque da planta, a vassoura-de-bruxa produz uma enzima chamada oxidase alternativa. Essa proteína lhe permite gerar uma quantidade mínima de energia e garante sua sobrevivência.
“Nesse período o fungo praticamente não cresce, pois a energia disponível é pequena, mas ele consegue resistir ao ataque”, disse Pereira.
Quando a planta finalmente dá a batalha por vencida, envia sinais para as células do galho infectado se suicidarem – processo conhecido como apoptose. Como o óxido nítrico deixa de ser liberado, o fungo desliga o mecanismo alternativo de respiração e entra na fase necrotrófica, passando a devorar vorazmente o tecido morto.
Em duas frentes
Os cientistas tiveram então a ideia de testar uma combinação de princípios ativos – azoxistrobina e ácido salicil-hidroxâmico – capazes de inibir simultaneamente os dois mecanismos respiratórios da praga.
“Observamos que quando a respiração principal é bloqueada pela azoxistrobina e a respiração alternativa se mantém, o fungo permanece na fase biotrófica. Mas, quando combinamos essa droga com um inibidor da oxidase alternativa, o fungo cessa completamente seu crescimento”, contou Pereira.
Embora tenha se mostrado promissora nos testes de laboratório, essa combinação de moléculas não pode ser usada como um fungicida comercial. “A fórmula é altamente instável e se degrada com facilidade. E isso inviabiliza o uso no campo”, disse.
A equipe agora trabalha, em parceria com a fabricante de defensivos agrícolas Ihara, para achar uma molécula com ação semelhante e capaz de se manter estável por longos períodos de prateleira.
“Temos a oportunidade de criar um produto realmente eficaz para fungos tropicais. Hoje não existe fungicida assim em nenhum lugar do mundo. É algo de grande importância tecnológica”, avaliou Pereira.
Os pesquisadores estão testando a mesma combinação de moléculas capaz de bloquear a enzima oxidase alternativa contra outras espécies de fungos tropicais, como a ferrujem da soja e do café. “Os resultados em laboratório indicam que estamos na direção certa”, disse.
Realizada com financiamento da FAPESP, a pesquisa faz parte do projeto de doutorado de Daniela Thomazella Paulo Teixeira , e está sendo realizada no âmbito do Projeto Temático “Estudo integrado e comparativo de três doenças fúngicas do cacau – vassoura-de-bruxa, monilíase e mal do facão – visando à compreensão de mecanismos de patogenicidade para o desenvolvimento de estratégias de controle”, coordenado por Pereira..
Os esforços brasileiros para elucidar o mecanismo de ação da doença que há mais de duas décadas afeta drasticamente a produção de cacau no Brasil começaram por volta do ano 2000, com o mapeamento do genoma da M. perniciosa.
Quando chegou ao sul da Bahia, em 1989, provavelmente vinda da região amazônica, a vassoura-de-bruxa fez com que a produção nacional caísse de aproximadamente 400 mil toneladas ao ano para pouco mais de 120 mil. O Brasil, antes um dos maiores exportadores de cacau, passou a importar sementes de países como a Indonésia, com qualidade inferior.
Atualmente, a doença está presente em todos os países produtores de cacau da América Central e do Sul.

Fonte: Internet

Ascom-Rezende


 

127 respostas para “Achado o ponto fraco da vassoura de bruxa”

  1. I simply want to say I am just all new to blogs and definitely enjoyed this web-site. Likely I’m likely to bookmark your site . You really come with awesome stories. Regards for sharing your web page.

  2. Oh my goodness! an amazing post dude. Many thanks Even so We’re experiencing problem with ur rss . Do not know why Unable to subscribe to it. Will there be anybody acquiring identical rss issue? Anybody who knows kindly respond. Thnkx

  3. Thanks for some other wonderful post. The place else may just anybody get that type of info in such a perfect way of writing? I’ve a presentation next week, and I am at the search for such information.

  4. Hello there, just became alert to your blog through Google, and found that it’s truly informative. I am gonna watch out for brussels. I will be grateful if you continue this in future. Numerous people will be benefited from your writing. Cheers!

  5. Awesome blog! Is your theme custom made or did you download it from somewhere? A design like yours with a few simple tweeks would really make my blog shine. Please let me know where you got your theme. Kudos Miss Samsung Fascinate

  6. I’ve observed that in the world today, video games will be the latest phenomenon with children of all ages. There are times when it may be extremely hard to drag young kids away from the video games. If you want the very best of both worlds, there are plenty of educational gaming activities for kids. Good post.

  7. My husband and i ended up being now more than happy that John could complete his investigations from the precious recommendations he acquired from your very own web pages. It is now and again perplexing to just choose to be making a gift of thoughts that men and women have been trying to sell. We remember we need you to be grateful to because of that. The entire explanations you have made, the straightforward web site menu, the relationships you can make it easier to promote – it is everything overwhelming, and it’s making our son and the family do think this theme is pleasurable, which is truly pressing. Many thanks for everything!

  8. I wanted to write down a quick word in order to express gratitude to you for all the remarkable hints you are posting at this site. My particularly long internet search has now been paid with high-quality details to exchange with my great friends. I would express that we visitors actually are truly endowed to be in a superb network with very many outstanding individuals with interesting basics. I feel rather happy to have used your website page and look forward to plenty of more enjoyable minutes reading here. Thanks once more for all the details.

  9. I think this website has some really great info for everyone. “I prefer the wicked rather than the foolish. The wicked sometimes rest.” by Alexandre Dumas.

  10. I love your blog.. very nice colors & theme. Did you make this website yourself or did you hire someone to do it for you? Plz respond as I’m looking to create my own blog and would like to know where u got this from. thanks

  11. I’ll immediately grab your rss feed as I can’t find your email subscription link or newsletter service. Do you’ve any? Kindly let me know in order that I could subscribe. Thanks.

  12. I’ve observed that in the world the present moment, video games include the latest popularity with kids of all ages. Many times it may be difficult to drag young kids away from the activities. If you want the very best of both worlds, there are numerous educational games for kids. Good post.

  13. That is the proper weblog for anybody who wants to find out about this topic. You realize a lot its almost onerous to argue with you (not that I really would need…HaHa). You undoubtedly put a new spin on a topic thats been written about for years. Nice stuff, simply great!

  14. Fantastic goods from you, man. I have understand your stuff previous to and you’re just too wonderful. I really like what you have acquired here, really like what you are stating and the way in which you say it. You make it entertaining and you still care for to keep it sensible. I can not wait to read much more from you. This is actually a wonderful website.

  15. Awsome info and right to the point. I am not sure if this is truly the best place to ask but do you guys have any ideea where to hire some professional writers? Thx 🙂

  16. Hello! I know this is kind of off topic but I was wondering if you knew where I could find a captcha plugin for my comment form? I’m using the same blog platform as yours and I’m having trouble finding one? Thanks a lot!

  17. Good – I should definitely pronounce, impressed with your web site. I had no trouble navigating through all the tabs and related info ended up being truly easy to do to access. I recently found what I hoped for before you know it at all. Quite unusual. Is likely to appreciate it for those who add forums or anything, web site theme . a tones way for your client to communicate. Nice task.

  18. Nice post. I learn something more challenging on totally different blogs everyday. It should always be stimulating to read content material from other writers and follow a bit something from their store. I’d desire to use some with the content on my weblog whether you don’t mind. Natually I’ll provide you with a hyperlink on your web blog. Thanks for sharing.

  19. I really appreciate this post. I’ve been looking everywhere for this! Thank goodness I found it on Bing. You’ve made my day! Thank you again

  20. I do not even know how I ended up here, but I thought this post was good. I don’t know who you are but certainly you are going to a famous blogger if you are not already 😉 Cheers!

  21. Have you ever considered publishing an e-book or guest authoring on other sites? I have a blog based upon on the same information you discuss and would really like to have you share some stories/information. I know my subscribers would appreciate your work. If you’re even remotely interested, feel free to send me an e mail.

  22. I intended to post you a bit of word to finally say thank you again for the pleasing pointers you have discussed on this site. This has been open-handed of you to provide openly all that many of us would have distributed as an e book to help make some dough on their own, especially now that you could have done it if you ever considered necessary. Those creative ideas in addition worked as the good way to know that other people online have similar dream the same as my personal own to find out great deal more in regard to this condition. I’m certain there are millions of more pleasant times in the future for individuals who see your site.

  23. Thank you for sharing superb informations. Your website is so cool. I’m impressed by the details that you have on this website. It reveals how nicely you understand this subject. Bookmarked this web page, will come back for more articles. You, my friend, ROCK! I found simply the info I already searched all over the place and simply could not come across. What a great web-site.

  24. I believe this website has got some very great information for everyone :D. “Nothing surely is so disgraceful to society and to individuals as unmeaning wastefulness.” by Count Benjamin Thompson Rumford.

  25. An impressive share, I simply given this onto a colleague who was doing a little evaluation on this. And he in fact purchased me breakfast as a result of I discovered it for him.. smile. So let me reword that: Thnx for the deal with! However yeah Thnkx for spending the time to debate this, I feel strongly about it and love reading extra on this topic. If attainable, as you change into expertise, would you thoughts updating your weblog with extra particulars? It’s highly useful for me. Massive thumb up for this weblog put up!

  26. I’m very happy to read this. This is the kind of manual that needs to be given and not the random misinformation that is at the other blogs. Appreciate your sharing this best doc.

  27. It¡¦s actually a cool and helpful piece of information. I¡¦m glad that you just shared this useful information with us. Please stay us informed like this. Thank you for sharing.

  28. Good blog! I truly love how it is simple on my eyes and the data are well written. I’m wondering how I could be notified whenever a new post has been made. I’ve subscribed to your feed which must do the trick! Have a great day!

  29. I must express my affection for your generosity for individuals that really want help on that concept. Your personal dedication to getting the message across came to be unbelievably invaluable and have constantly encouraged employees much like me to get to their desired goals. Your new valuable guideline means a lot to me and still more to my mates. Warm regards; from everyone of us.

  30. I would like to thank you for the efforts you have put in writing this web site. I am hoping the same high-grade web site post from you in the upcoming as well. In fact your creative writing skills has encouraged me to get my own website now. Actually the blogging is spreading its wings quickly. Your write up is a good example of it.

  31. Thanks for sharing superb informations. Your web-site is so cool. I’m impressed by the details that you’ve on this web site. It reveals how nicely you understand this subject. Bookmarked this web page, will come back for more articles. You, my pal, ROCK! I found just the information I already searched all over the place and just couldn’t come across. What a perfect site.

  32. Keep up the wonderful piece of work, I read few blog posts on this internet site and I conceive that your weblog is really interesting and holds circles of great info .

  33. I needed to write you the bit of note to finally thank you very much as before over the pleasing ideas you have contributed in this case. It was quite wonderfully generous with people like you to make easily just what a number of people would’ve made available for an electronic book to earn some dough for their own end, notably since you might have done it in case you wanted. Those techniques also worked like the fantastic way to recognize that the rest have similar dream just like my personal own to grasp a great deal more on the subject of this matter. I believe there are a lot more enjoyable periods in the future for many who view your blog post.

  34. I truly appreciate this post. I have been looking everywhere for this! Thank goodness I found it on Bing. You have made my day! Thank you again

  35. It’s in point of fact a nice and helpful piece of info. I am happy that you shared this useful info with us. Please keep us up to date like this. Thanks for sharing.

  36. I’m often to blogging and i actually recognize your content. The article has really peaks my interest. I’m going to bookmark your website and maintain checking for new information.

  37. It’s my belief that mesothelioma can be the most lethal cancer. It’s got unusual properties. The more I look at it the harder I am convinced it does not act like a real solid flesh cancer. When mesothelioma is often a rogue virus-like infection, hence there is the prospects for developing a vaccine and offering vaccination to asbestos uncovered people who are at high risk associated with developing long run asbestos associated malignancies. Thanks for sharing your ideas about this important ailment.

  38. Does your site have a contact page? I’m having a tough time locating it but, I’d like to send you an email. I’ve got some suggestions for your blog you might be interested in hearing. Either way, great website and I look forward to seeing it develop over time.

  39. Thanks for these tips. One thing I should also believe is the fact credit cards offering a 0% apr often lure consumers along with zero monthly interest, instant authorization and easy on the web balance transfers, nevertheless beware of the main factor that may void your current 0% easy street annual percentage rate and throw you out into the bad house rapidly.

  40. I do believe all the ideas you have introduced in your post. They are really convincing and will definitely work. Still, the posts are too brief for novices. Could you please prolong them a little from next time? Thanks for the post.

  41. Somebody essentially help to make seriously articles I would state. This is the first time I frequented your website page and thus far? I surprised with the research you made to create this particular publish amazing. Great job!

  42. Great – I should definitely pronounce, impressed with your website. I had no trouble navigating through all tabs as well as related info ended up being truly simple to do to access. I recently found what I hoped for before you know it at all. Reasonably unusual. Is likely to appreciate it for those who add forums or anything, web site theme . a tones way for your customer to communicate. Excellent task.

  43. An impressive share, I simply given this onto a colleague who was doing a bit analysis on this. And he in fact purchased me breakfast as a result of I found it for him.. smile. So let me reword that: Thnx for the treat! However yeah Thnkx for spending the time to debate this, I feel strongly about it and love studying extra on this topic. If doable, as you turn out to be experience, would you thoughts updating your weblog with more particulars? It’s extremely useful for me. Huge thumb up for this blog put up!

  44. Thanks for sharing excellent informations. Your web-site is so cool. I’m impressed by the details that you’ve on this blog. It reveals how nicely you perceive this subject. Bookmarked this web page, will come back for more articles. You, my friend, ROCK! I found simply the info I already searched all over the place and just couldn’t come across. What a great web-site.

  45. Thanks for the guidelines shared using your blog. Something else I would like to say is that losing weight is not about going on a dietary fad and trying to get rid of as much weight as possible in a set period of time. The most effective way to burn fat is by getting it slowly but surely and obeying some basic ideas which can enable you to make the most from the attempt to shed weight. You may recognize and be following some of these tips, nonetheless reinforcing know-how never hurts.

  46. I like what you guys are up also. Such intelligent work and reporting! Keep up the superb works guys I have incorporated you guys to my blogroll. I think it will improve the value of my website :).

  47. Good day very cool site!! Man .. Beautiful .. Amazing .. I will bookmark your site and take the feeds also…I am glad to find numerous helpful information right here in the post, we need work out extra techniques on this regard, thanks for sharing. . . . . .

  48. hello!,I love your writing so much! share we keep up a correspondence extra approximately your post on AOL? I require an expert in this space to solve my problem. May be that’s you! Taking a look ahead to peer you.

  49. Thanks for these tips. One thing I also believe is always that credit cards supplying a 0% interest rate often lure consumers with zero rate, instant approval and easy on the net balance transfers, however beware of the most recognized factor that will certainly void your own 0% easy streets annual percentage rate plus throw anybody out into the poor house rapid.

  50. Aw, this was a very nice post. In thought I want to put in writing like this moreover – taking time and precise effort to make an excellent article… but what can I say… I procrastinate alot and not at all appear to get one thing done.

  51. Wow! This can be one particular of the most useful blogs We’ve ever arrive across on this subject. Actually Magnificent. I’m also a specialist in this topic so I can understand your hard work.

  52. Thanks for the helpful article. It is also my belief that mesothelioma has an incredibly long latency phase, which means that indication of the disease may well not emerge till 30 to 50 years after the 1st exposure to asbestos. Pleural mesothelioma, which can be the most common type and has an effect on the area about the lungs, could cause shortness of breath, upper body pains, as well as a persistent coughing, which may bring about coughing up blood.

  53. This design is steller! You obviously know how to keep a reader amused. Between your wit and your videos, I was almost moved to start my own blog (well, almost…HaHa!) Great job. I really loved what you had to say, and more than that, how you presented it. Too cool!

  54. UsuallyNormallyGenerally I do notdon’t readlearn articlepost on blogs, howeverbut I wish towould like to say that this write-up very forcedpressuredcompelled me to take a look atto tryto check out and do soit! Your writing tastestyle has been amazedsurprised me. Thank youThanks, quitevery greatnice articlepost.

  55. My programmer is trying to persuade me to move to .net from PHP. I have always disliked the idea because of the costs. But he’s tryiong none the less. I’ve been using Movable-type on several websites for about a year and am nervous about switching to another platform. I have heard fantastic things about blogengine.net. Is there a way I can transfer all my wordpress posts into it? Any help would be greatly appreciated!

  56. We are a group of volunteers and starting a new scheme in our community. Your website provided us with valuable info to work on. You’ve done a formidable job and our whole community will be grateful to you.

  57. Good day! I could have sworn I’ve been to this blog before but after checking through some of the post I realized it’s new to me. Anyhow, I’m definitely glad I found it and I’ll be bookmarking and checking back often!

  58. Pretty section of content. I just stumbled upon your web site and in accession capital to assert that I acquire in fact enjoyed account your blog posts. Any way I will be subscribing to your augment and even I achievement you access consistently rapidly.

  59. Hello.This article was extremely fascinating, particularly because I was investigating for thoughts on this topic last Saturday.

  60. Great goods from you, man. I have understand your stuff previous to and you are just extremely great. I actually like what you have acquired here, certainly like what you’re saying and the way in which you say it. You make it enjoyable and you still care for to keep it smart. I can not wait to read far more from you. This is actually a great web site.

  61. Just wish to say your article is as astounding. The clearness in your post is simply great and i could assume you are an expert on this subject. Fine with your permission let me to grab your feed to keep up to date with forthcoming post. Thanks a million and please continue the enjoyable work.

  62. I believe that avoiding ready-made foods may be the first step to be able to lose weight. They can taste fine, but packaged foods have very little nutritional value, making you take in more simply to have enough vigor to get through the day. In case you are constantly ingesting these foods, changing to whole grains and other complex carbohydrates will help you to have more vigor while eating less. Interesting blog post.

  63. It’s a shame you don’t have a donate button! I’d definitely donate to this excellent blog! I guess for now i’ll settle for book-marking and adding your RSS feed to my Google account. I look forward to fresh updates and will talk about this website with my Facebook group. Talk soon!

  64. I do trust all of the ideas you’ve presented on your post. They are really convincing and can certainly work. Still, the posts are too quick for novices. May you please prolong them a little from next time? Thanks for the post.

  65. Greetings from Carolina! I’m bored to death at work so I decided to browse your site on my iphone during lunch break. I really like the info you provide here and can’t wait to take a look when I get home. I’m amazed at how fast your blog loaded on my cell phone .. I’m not even using WIFI, just 3G .. Anyhow, excellent site!

  66. I carry on listening to the news broadcast lecture about receiving free online grant applications so I have been looking around for the most excellent site to get one. Could you advise me please, where could i acquire some?

  67. Undeniably believe that which you stated. Your favorite reason appeared to be on the internet the easiest thing to be aware of. I say to you, I certainly get irked while people think about worries that they plainly don’t know about. You managed to hit the nail upon the top and defined out the whole thing without having side effect , people could take a signal. Will likely be back to get more. Thanks

  68. My brother recommended I might like this website. He was entirely right. This post actually made my day. You can not imagine simply how much time I had spent for this information! Thanks!

  69. I am curious to find out what blog system you’re working with? I’m having some minor security issues with my latest blog and I would like to find something more safe. Do you have any suggestions?

  70. I am curious to find out what blog system you have been utilizing? I’m having some minor security issues with my latest blog and I’d like to find something more secure. Do you have any suggestions?

  71. Another important component is that if you are a senior citizen, travel insurance with regard to pensioners is something you need to really consider. The old you are, the greater at risk you might be for permitting something awful happen to you while in another country. If you are not covered by a number of comprehensive insurance cover, you could have a few serious difficulties. Thanks for sharing your advice on this web site.

  72. Good website! I really love how it is simple on my eyes and the data are well written. I am wondering how I could be notified whenever a new post has been made. I have subscribed to your feed which must do the trick! Have a great day!

  73. Wonderful work! That is the type of information that are supposed to be shared across the web. Disgrace on the seek engines for not positioning this submit higher! Come on over and talk over with my site . Thanks =)

  74. Hello, you used to write fantastic, but the last few posts have been kinda boring¡K I miss your tremendous writings. Past several posts are just a little out of track! come on!

  75. I would like to thank you for the efforts you’ve put in writing this blog. I am hoping the same high-grade web site post from you in the upcoming as well. Actually your creative writing abilities has encouraged me to get my own site now. Actually the blogging is spreading its wings fast. Your write up is a good example of it.

  76. We are a group of volunteers and starting a new scheme in our community. Your site offered us with valuable info to work on. You’ve done an impressive job and our whole community will be thankful to you.

  77. You could definitely see your expertise in the work you write. The world hopes for more passionate writers like you who aren’t afraid to say how they believe. Always follow your heart.

  78. Youre so cool! I dont suppose Ive read anything like this before. So good to search out any person with some unique thoughts on this subject. realy thank you for starting this up. this website is one thing that is wanted on the web, somebody with just a little originality. useful job for bringing something new to the web!

  79. I am not sure where you’re getting your information, but good topic. I needs to spend some time learning much more or understanding more. Thanks for fantastic info I was looking for this info for my mission.

  80. Nice read, I just passed this onto a colleague who was doing some research on that. And he actually bought me lunch as I found it for him smile Thus let me rephrase that: Thanks for lunch!

Deixe um comentário

O seu endereço de e-mail não será publicado.