Science method

Rooting - Science method

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What is the role of temperature for inducing or maintaining the roots in hydroponic condition? How to maintain rooting temperature at optimum condition?
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Nutrient solution temperature influences several important variables, foremost of which are oxygen solubility and plant metabolic processes. With rising temperatures, the rate of metabolic reactions occurring in the plants will increase.
Temperatures below or above optimum levels may influence plant metabolic activities positively or negatively. This may include accumulation of different metabolites such as phenolic compounds, reactive oxygen species (ROS), nutrient uptake, chlorophyll pigment formation, the photosynthesis process and finally the growth and development of the plant.
You should also access the attached pdf.
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I think to improve the growth of pomegranate seedlings when they planted in the orchard soil because some of seedlings may be died or growth weakly. The rooting stimulants were applied to get out more roots of cuttings, therefore I hope the ability of these stimulants benefit the transplants when were planting.
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Yes, biostimulants can promote rooting, and hence the overall growth of transplants in the field. Mycorrhiza, PGPRs, humic acid, polypeptides+amino acids, seaweed extracts, etc. can be useful plant biostimulants.
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Anther derived plants of oil seed(niger) were raised in-vitro. After successful rooting, hardening is becoming difficult . Can any one suggest for proper hardening conditions for 100% plant survival.
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Spray with glycine 50 and 100 mg / liter twice, the interval between the two sprays is two weeks
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I have done genetic transformation of tobacco with leaf disc method. Now, my calluses have been sprouting small leaves. I want to confirm the presence of my transformed gene. Kindly suggest me, how long should I wait to shift them to shooting and rooting media? Or can I confirm the presence of gene at this stage without utilizing whole callus? Also, they have been catching fungus, so I am left with only few calluses. Shall I rely on them? or Shall I infect more explants?
Thank you.
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The attached article showing different steps of an efficient gene transformation method.
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I would be interested to hear about rooting depth of alder trees and the effect on peat quality. To my knowledge the peat layer of alder swamps is comparatively shallow compared to other fens systems, i.e. in some case only few decimeters. I would suspect that this phenomenon is inter alia also linked to the fact that there is oxygen release in the rhizosphere but also the N fixation by roots might be of importance?! For the rooting depth I found this work: https://academic.oup.com/forestry/article/83/2/163/519324 stating that it can be up to 5 m?! However, I wonder if peat of alder swamps is typically more decomposed because of the mentioned root activity or is it the fact that naturally alder swamps experience naturally larger water table fluctuations?!
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Yea interesting facts Dominik Zak
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Which are the different ways to enhance more rooting in black pepper cuttings
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You may use auxin hormones but I am not do sure. But when we in vitro culture of plants we use higher concentration of auxin to induce rooting.
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Hi to everyone,
I´m transforming explants of Nicotiana tabacum with agrobacterium following Clemente´s procedure. In what size or stage of the shoots is advisable to transfer them into rooting medium? And how much time it takes to generate roots?
Thank you in advance.
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If you are growing them in tissue culture, we basically transfer them to the rooting media as soon as possible when the first leaf has popped up on the explant. In other cases, we include rooting hormone in the same media.
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Hello everyone! I am looking for some statistical help!
I am working in in vitro micropropagation and one of the aspects that I am studying is the rooting of plants in 10 different growing media. For that, I categorize the rooting of the plants as 0 (no roots) or 1 (rooting). Therefore, I have one categorical independent variable (rooting medium) with 10 different categories and one categorical dependent variable with two categories (0 and 1). My sample size is 30 plants per medium.
From those numbers, I obtain a rooting percentage for each medium and I would like to now if this parameter differs significantly between the different media.
I would like to know how I should compare my data. These are the tests I have done but do not know which one to use:
- 2x10 contingency table in SPSS and Chi-2 test. This gives me a p value for the whole experiment. For post hoc, I have used a Z-test.
- I have also tried a univariate GLM in SPSS with a tukey post hoc test.
I do not know if both are valid or if I should just stick to the contingency table.
Any help would be appreciated
Thanks!
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Maybe I am reading this differently from Jochen Wilhelm and others, so am taking a different tact (but am certainly willing to be convinced that I am wrong ... and this is not my substantive area, so ... ). My concern is with a statistical approach that has 9 values that are the focus and the power of post hoc tests with this many categories. In order to offer guidance, I have a question.
Do you have any ideas/theories/hunches about the relationships among the 10 categories?
If yes, use these ideas in you model to focus what you are looking at.
If not (so these are just random categories that were picked), presumably your interest is just whether there is more variability among these categories than expected if the categories don't make a difference. Then, you'd probably want to allow the intercept to vary by category, and might assume the distribution of these intercepts is random, and then just have a single number (the variance) that you are focused on.
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These cannabis plants were healthy and green for 8 weeks and they started browning when I put them in rooting media. No rooting achieved and they are turning brown.
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Hi Poorva. I like your project. From my experience of cloning eucalyptus species from axillary buds, I have seen over the years that one needs to incorporate antioxidants in the medium to reduce the production of phenolic compounds which hinder culture growth. I usually use PVP to reduce the effect of phenolic compounds exudation. For rooting, it is wise to include a lower concentration of rooting hormone, like 0.05 mg/l for bud induction and increase it to 0.01mg/l for elongation and finally 0.1mg/l for your rooting phase. This helps as some clones do not even need addition of rooting hormone at rooting phase. This is my strategy when dealing with shy rooters for eucalyptus clones and hope it will solve your frustration. Good luck.
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I want to study vegatative propagation by cutting. My plant is parrotia persica.
Did you study on this plant's propagation?
Please say your experience to me.
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Please take a look at this useful RG link.
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Is there a theoretical rooting for the mechanisms of transmission of monetary shocks?
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I wonder if you consider only the traditional monetary policy or the QE policy as well. I think that the QE approach is very good for considering the monetary shocks...
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Hello,
I have a problem with magnolia shoots rooting. For the rooting of in vitro produced shoots, I have used MS basic medium containing auxins (NAA and IBA, ranging from 0.5 to 4.0 mg l−1), but withour effect. I also tied ex vitro roooting method. The in vitro produced shoots were treated with comercial rooting auxin (IBA). The bases of shoots were treated with IBA for 12 h. Auxin treated shoots were directly transferred to soil and kept in the greenhouse for rooting. It was done 2 weeks ago I steel wait for results. Does anyone experience with magnolia in vitro propagation? Thank you for any suggestion.
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A variety of auxins with different ratios were assayed for rooting of shoots but rooting was not performed.
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I have been trying to generate transgenic poplar plants NM6 in WPM media and with different rooting hormones. My plants haven't been rooting so far.I transferred some into 1/2 MS with IBA, but there are still no roots. I welcome any suggestions you might have!
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try salt MS media
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I have a subset of eukaryotic proteins for which I want to find out from which prokaryotic phylum these proteins originated from. So I blasted these group of proteins against the prokaryotic database and have a set of hits. I grouped the eukaryotic and prokaryotic proteins into protein families using ML and made phylogenetic trees for each family using RaxML. My question is which outgroups can I use to root the phylogenetic trees and whether is it even necessary beyond what is done by default by RaxML? Is drawing conclusions about sister group relationship between eukaryotic and prokaryotic proteins dependent on rooting the trees with proper outgroups?
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It sounds like you might be able to draw an inference about the origin of the proteins without rooting the tree, as long as you are willing to assume that the eukaryotic proteins did indeed originate from prokaryotes, rather than, say, the prokaryotes picking up a protein from a eukaryote somehow. Basically, I would look at the point the tree where the (presumably) monophyletic eukaryotic sequences are attached to some group of prokaryotes. That group is the likely sister taxon.
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I am currently working on the adventitious rooting through cuttings, I have used WinRHIZO 2013 software to measure root parameters including root volume. I am confused about the increase or decrease in root volume. Does anyone know that what reasons may cause increase or decrease in plant root volume?
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I got your point, this might be the reason for the roots of my plants too.
Again very thanks for the answer Nina Shishkoff
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Hi everyone we are in the process of standardizing the micro-propagation protocol of culinary banana (ABB) for commercial scale production. But, unlike Grand Naine and other table varieties of banana these culinary types are showing more elongation, lanky and week growth while hardening (Picture attached). Further we also recorded low survival in field condition. In this contest i am planning to use some additional media supplements in in vitro (may be before in vitro rooting step) to improve the plant health condition there by more field survival. I am requesting the experts to suggest the media supplements to produce the good quality planting material.
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Sir, Thank you for quick reply. But the information which i needed is not available in the articles tagged by you. We have developed standardized protocol for ABB group but the resultant shoots were lanky and not vigorous. So i want to use some of the chemicals like Chitosan, Paclorobutrazol, high Sucrose, Silver nitrate etc. to improve the vigor of the micro-shoots by adding these supplements in one or two cycles in in vitro. I am in search of other additives for producing healthy and sturdy tissue culture plants in commercial scale.
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In order to rooting strawberry cutting in-vitro which type of auxin i can use and the concentration of them?
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Thanks...
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I have transformed nucleus of Nicotiana benthamiana with LBA4404 Agrobacterium strain harboring gene of interest that was Chloroplast Transit Peptide + aadA gene for spectinomycin resistance. I infected leaf discs with LBA4404 and grown them on Spectinomycin containing MS medium, spectinomycin seems to be working properly as the color of leaf discs has been bleached out and the callus formed is also swollen, it is almost 3 months and my callus didn't started shooting and rooting yet. I have used the appropriate Hormones for that purpose which are: BAP 500 uL/500 ml, NAA 50 uL/500 ml, Spectinomycin 750 uL/500 ml, Cefotaxime 500 uL/500 ml. Why am I not getting shoots and roots in my calli, is there any problem with the Hormonal or Spectinomycin concentrations that I am using? Kindly suggest me the best way to counter this problem. Reference papers would also be best in this regard.
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Hi, Jazib Ali Irfan, I had the same issue, did you figure it out eventually?
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How to avoid such Tissue culture problem
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Dear Wasif,
This kind of contamination is frequent in tissue culture. It's not necessary from endophitic origin. In fact, according to the pictures, I might be sure that it's not and endophitic contamination. In this case, the origin might be associated with problems with manipulation, even mistakes in culture media esterilization can be considered.
My advise is don't waste time trying to recover the contaminated explants; however, if you find some explants free of contamination, you can subculture it to fresh medium. Check all the time for new contaminations.
Regards and good luck
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I have mutant of kalanchoe I'm currently working with but the young plants are finding difficult to produce enough roots to survive in the soil.
How will I make these plants root?
Any helpful suggestion will be appreciated.
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Hi Nina,
Thanks for answer.
Your idea will help.
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Hello all,
I am studying the effect of sugars on rooting of Dianthus sp. in tissue culture for my internship report and I grew some plants on medium that did not contain any sucrose. The medium did contain 2.46 g/L McCown Woody Plant Medium, 0,1 mg/L IBA and 6 g/L micro agar. Strangely the plants grew just as good as the media that did contain sucrose, and after five weeks the are still growing and of good quality. Could it be that the plants are using the micro agar as a carbon source?
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It is unlikely that your plants are using agar as a significant sugar source. Sucrose addition to media tends to make the most difference in the very early stages of plant growth. Once the plant is established and growing then the plant will produce its own sucrose via the dark rections of photosynthesis.
It is entirely possible that your seeds have enough sugars stored within them to get the plants established and to the point where they are producing their own sucrose. There might still be phenotypes associated with sucrose content in the media (sucrose is a prolific signalling molecule after all) but I wouldn't expect your plants to die due to the lack of it.
Having said that if your plants look different under a no sucrose regime than previous experiments in your lab under similar conditions then it is possible that your batch of agar is contaminated with sugar and you would want to find a way to test that. I have never done this but my first try would be to soak some agar in cold water (the agar won't dissolve without heating but mobilisable sugars should dissolve), centrifuge your sample to pellet the undissolved agar and take the supernatant, then do a test for sugars (perhaps use Benedicts reagent)
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I am using the same medium and PH in which I started the plantlets but I change the hormones to only IBA and my green shoots turned red with
no roots at all.
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Dear Dr. Cartes, try adding active charcoal in your medium, if you have that option. 0.8 g/L should be enough. Also I agree with Dr. Baltierra that ex vitro rooting could be another way to solve your problem.
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I work at Center for Advanced research in Plant Tissue Culture, Anand Agricultural University, Anand, India. Currently I am woking on micropropagation of Sandalwood. I have successfully completed multiplication but finding difficulties in rooting phase. I have experimented various approaches for in vitro rooting such as higher auxin levels, combinations of auxins, pulse treatments, various hosts, biotic as well as abiotic stress but none of them have proved viable. The frequency of getting roots is very low (only 1 at every 100). Please suggest a reliable method for high frequency rooting.
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Tripathi et al High frequency in vitro regeneration of sandalwood (Santalum album Linn. September 2017. Medicinal Plants - International Journal of Phytomedicines and Related Industries 9(3):154
please refer to the above
also, as against the previous beliefs it is been reported that CK has an equally imprtant role in rooting induction as auxin, please refer to one article "releasing cytokinin brakes on rooting" which featured in journal of plant physiology, this issue or the previous one
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Rooting problem.
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Half strength MS plus different combinations of NAA and IBA
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I am using different method but there are not successful
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Hi
What is the plant species tested and how do you do it?
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I have a problem in rooting of kiwifruit plants in tissue culture condition, I am applying different treatments can anyone help me?
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You can use 0.5 mg/l IBA
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I have been propagating a poplar hybrid (717) in sterile tissue culture with 1/2 MS media and no hormones. My last few batches haven't been rooting well. I have replanted some into 1/2 MS with IBA, but there are still no roots. I welcome any suggestions you might have!
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Dear Emel,
If you explants are not rooting, but have a well-developed shoots mean that shoot-derived auxin does not transported properly. IBA/IAA is not very effective in this case, because you need good auxin transport, not auxin itself.
MS has a very high N contents what is not beneficial for the rooting (as well as other process). And far from optimal ions ratio.
Try to use better medium like Hg or more close to natural.
My best wishes!
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Dear lovely friends,
I am working with many perennials. One of them is Ophiopogon. Maybe sombody know which auxin and at what concentration I have to use for quicly rooting of shoots in vitro?
Each info will be great 😉
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Arvind Singh and Seied Mehdi Miri thanks a lot :)
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I was looking for any reading material about nexus between species successional status and rooting pattern for Australian wet tropical rainforest species? Any help is highly appreciated. Thanks...
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There is surely a presence of such nexus. However , it will be more interesting to know, whether or not , such nexus will lead greater allocation of C to roots..??
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I am unable to regenerate plants from the callus obtained from apical meristems. Also, the callus response is not defined and changes frequently and is not replicating. The variety produces a lot of phenolics and before they reach regeneration , they die. I find it hard to decide whether to go for calli that are compact and hard or calli that are friable and wet. The wet ones do not survive on the regenertion (shoot) medium whereas compact ones produce rooting response on the regeneration (shoot) media. Phenolics are a big problem and the type of callus also. Please suggest solutions for troubleshooting the media composition.
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charcoal scanvenges or sequesters all the hormones and affects the callus growth. Is there any other means to exclude tannins and phenolics secreted by the plant without sequestration of hormones and additives?
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I want to information about the best auxin, can be used in rooting of shoots by plant tissue culture.
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K salt of IBA is the most appropriate in general when you need to keep the control of the root number and at the same time you would like to avoid excess of callus. Keep your initial IBA mother solution in the dark (it is the same with IAA!). You can get additionnal auxin activity using different substances (Vit D2, proline, as examples) and treatment (3-5 days in complete darkness at the lab temperature from the begining of the rooting stage as example) and control callus formation by using riboflavine that oxydize exogenous auxin from the moment you move the culture to the light). The results could be variable according to the physiological status of your plant material. try to homogenize your plant material before its transfer to auxin medium)
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working on the effect of various culture mediums on invitro rooting, I wanna calculate rooting speed, is there any distinct formula in this regard?
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yea , that's it....
thanks for sharing your answer..
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I wanna know that, in what way PPO affect rooting potential? in other words, is it probable that agents that decrease PPO activity, result in enhanced rooting? 
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Polyphenol oxidase can work as an IAA oxidase, and hence reduce the amount of auxins. Auxins are known to directly affect the rooting of plants. If you are affecting on polyphenol oxidase, then you act on rooting and cell growth by stretching.
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The full strength of MS medium gave weakness growth in roots.
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Please find some interesting work...
Abstract. Multiple shoots were obtained from shoot tips (2 to 3 mm) derived from matureplants (5 to 6 years old) of Citrus reticulata Blanco CV. Khasi mandarin and C. limonBurm.f. CV. Assam lemon when cultured on Murashige and Skoog (MS) medium,supplemented with (mg·liter–1) 1.0 BAP, 0.5 kinetin, and 0.5 NAA. Root induction wasobserved when 7-week-old single shoots (» 2 cm long) of both Citrus species were culturedon MS medium supplemented with (mg·liter–1) 0.25 BAP, 0.5 NAA, and 0.5 IBA. Theseplantlets were successfully established in the soil. Chemical names used: naphthaleneacetic acid (NAA), indole 3-butyric acid (IBA), and benzylamino purine (BAP). Source :HORTSCIENCE 29(3):214-216. 1994, PDF enclosed for further reading..
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Propagation
physiology
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Considero que sería adecuado que pruebes con la información que te envié, es muy probable que el enraizamiento sea más adecuado con arena y además con estacas apicales. Es común que las podocapaceas tengan un periodo de enraizamiento de más de 100 días incluso con auxinas. Ten mucho cuidado con el manejo de la húmedad y la aireación, un mal manejo de estos conduce a pudrición completa del material.
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 If so then what is the reason or cause behind it. Is there any paper or article mentioning about it.  Please send some paper releated to it.
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In Eucalyptus BAP has a negative effect on rooting when it accumulates in tissues after many cycles of multiplication. Sometimes it is necessary some subcultures in medium with activated charcoal to detoxify the explants and recover the rhizogenic capacity.
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I am working on tissue culture of opium poppy but have one problem in rooting optimization. Can everyone help me, please?
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the basic idea is use low salt based medium or low nutrient medium, like 1/2 MS, plus auxin at a certain concentration, if cytokinin used, keep them at low portion. sometimes dark envirenment also help by including activate carbon in the medium. 
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Many papers are misleading for shoot multiplication, so if anyone have really tried of rooting kindly provide details,,,
I would also like to know which auxin gives the best result with the given species?
It would be a great help,,
Thank you all..
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please, use have strength MS   with the auxin NAA at 0.2 mg per liter, for excellent rooting..
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Rooting of invitro plant cultures.
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Hi Leelavathy,
Please see the similar discussion on RG:
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The type of soil that will allow the roots to be easily evaluated.
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We use "Profile - porous ceramic"   Type: "Greens Grade"
This give good root development and does not adhere to the roots, allowing them to be cleaned easily after excavation.  If you are doing in vivo evaluations, I have little to suggest since I find all transparent media to be questionable for root structure development.  There is one other, however, that uses clear beads with a method to provide easy visualization/photographing as well as relatively clean roots after extraction.  They claim total transparency, but I have not tested the system.
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I tried callus initiation in MS media containing different concentrations of BAP, Kinetin and 2,4-D in combinations. The same combinations help to initiate and maintain calli from other explants well but not in case of leaves. In leaf explants,however, I got more of rooting than callus formation with these combinations. Can someone help me with this?
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Hi,
I would also suggest 2,4-D- in range from 0.5-2 micromole will work, if not than you can increase the concentration.
Combining the Cytokinins with auxins may give you callus but it can be a morphogenic one and not friable or compact.
other things you can try is-
1) at the time of inoculation, wound the explant at the surface that touches to the medium, it would increase the chance and/or size of callus;
2) change the position of explant inoculation i.e. abaxial to adaxial or vice versa, as this can sometimes induce callus, i observed it in Bacopa monnieri leaf explant.
Hope it will work. 
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I am getting in vitro roots in my plant of family convolvulaceae on GA3. So can anyone please provide me such papers or suggestions which support my result?
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You welcome 
all the best
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What plant regulator is best for rooting mascaro coffea?
Mascaro Coffea belongs to the coffee family. Absence of caffeine.
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For rooting of most plant species, IBA is recommended. The rate of application, however, depends on the age of the cutting (softwood, semi-hardwood or hardwood) and the nature of the plant's response for ease rooting. Most importantly, for coffee you should be very careful in selection of branches. Normal and healthy plants are mostly obtained from rooting of orthotropic branches as compared to cuttings taken from plagiotropic branches.
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During direct regeneration of Chickpea, the shoot tips start to get brown just after a few day of sub-culturing to multiple shooting medium or to rooting medium and stop responding. What may be the reason?
What is the solution to this problem?
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This "browning" or "blackening" as usually referred is due to the accumulation of phenolic compounds, principally because of the activation of the secondary metabolism due to the stress that in-vitro culture is causing to the explants.
For solving this problem there are many things you can try... I leave a link that may help
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I have a dataset or co-occuring trees sampled  from a stand. Predawn water potential varies during the dry season. Since we assume that predawn water potential depends is measured at low (or 0) transpiration rates I tend to argue that the differences are due to differences in rooting depths. However, I wonder have connections of predawn water potential and rooting depths been explored in a systematic way?
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Hi Frank,
Theoretically, if some trees are rooted in deeper/wetter soil than their neighbors, you would expect to see relatively higher predawn water potentials, provided that the plant is in equilibrium with the soil. It would be necessary to verify soil moisture profiles. In practice, such an approach tends to be problematic. You might also consider the use of stable isotopes. Here is a paper you may find helpful.