indigo264nm Posted April 17, 2006 These two aren't looking good and I need to know why. I have a healthier one which is a good deal bigger (despite germinated same time) and he looks good but still showing some of the basic symptoms which have overtaken these youngns. I know it could be something as simple as sunlight or soil... Any ideas as to what could cause such phyllode damage??? As I have about 9 baby tubes under HPS which have just been pricked out from the tray and although for now they are safe inside I don't want to make the same mistake and wish to end up with these 9 happy and healthy (and with the other 6 dreg seedlings from the tray, they can just do the best that they can I guess). Cheers, Chris. Share this post Link to post Share on other sites
planthelper Posted April 17, 2006 proly overwatering caused some type of pathogen to hurt the roots. keep drier, allowe for longer dry spells betweeen watering. this symptom is common with those accacias, they are tricky in pots. planting out seems to avoid those problems. this accacia lives in symbiosis with some type of bacteria which maybe not only helps it to take up nutes, but aswell protects, the latter part is just an idea... anyway, it seems to help a great deal, if you use soil from places where this plant grows in the wild. Share this post Link to post Share on other sites
indigo264nm Posted April 17, 2006 I'm gonna plant some out eventually but just wanna grow in pots for a bit... Get the hang of it so maybe I can offer out some healthy hardened kiddies for trade or as gifts. Should have added more perlite to the mix, but at least I remembered to do that with the new seedlings. I shall refrain from watering so much. How are these things with sunlight - The more the better or keep em a bit more sheltered??? Share this post Link to post Share on other sites
planthelper Posted April 17, 2006 around 50% direct sunlight, at this stage. they can take a lot of light if they are happy, provided it doesn't get too hot. btw, they hate it aswell if they get underwatered. remeber, naturally they grow in rather coolish aspects with water close by. i once killed one plant in situ by not watering enough over the hot summer, in this case the phyllodes get brown aswell, however the border between green and dry brown looks very pronouced. Share this post Link to post Share on other sites
Amulte Posted April 17, 2006 def root rot id say. PH said it 4 me Share this post Link to post Share on other sites
Ed Dunkel Posted April 17, 2006 Are those fertiliser pellets? (even if they are slow release) This might also be a problem. Over fertilization, too much of a particular nutrient. Acacia's like soils poorer in Nitrogen, generally. The "over-watering" would definitely not help either. Concider it when re-potting Good luck, and plant out as sson as appropriate. Share this post Link to post Share on other sites
Rev Posted April 17, 2006 I use pellets in mine too p/helper freaked when he saw that ! but REALLY i have NEVER killed any natives with phosphorus i feed them just like any other tree stocks i seriously doubt the validity of the low nute argument for young plants except with proteaceae and their proteoid roots also i see no problem with lots of water so long as drainage is sharp looking t that mix id have cut it at least by a third with coarse sharp sand Interesting they leaves are crisp from the tips back the main stem looks good If they were mine id plant them in the ground now mulch with some leaf litter from the base of a longifolia and brush my hands off and set about growing more tubetocks thats a good a chance as they will get If they stay in post much longer than this you will see their ultimate potential dwindle to nought Share this post Link to post Share on other sites
foolsbreath Posted April 17, 2006 Acacia's have symbiotic fungi that help fix nutrients and carbon from the soil. These are particularly helpful for seedlings. Lots die after about 6 months without these fungi. These fungi can be a mixture of VAM or ECM fungi, or just VAM alone. These fungi grow on the roots and effectively expand the root area greatly in their symbiotic nature. You can bye innoculum for these fungi or take some soil from a soil core of an acaia and use that. These fungi also keep away other pathogens that can cause rot etc Share this post Link to post Share on other sites
foolsbreath Posted April 17, 2006 Check this site out for the roles of ECM in australian plants ECM Fungi roles in australia Share this post Link to post Share on other sites
Rev Posted April 18, 2006 im well familar with that it just needs to be noted that rarely is the fungal association obligatory in extreme low nutrients it cant occur and in high nutrients it is depressed it is on the leaner side of normal is where it peaks My acacias have spontaneously picked up rhizobium from dust or the air ive never innoculated them on purpose I would rate the rhizobium far above the VAM and esp ECM in importance to the plant Share this post Link to post Share on other sites
foolsbreath Posted April 18, 2006 All True Rev, especially phosphorous is an inhibitor to fungal health Studies have shown an increase in survival of seedlings from 49% to 90% with the introduction of symbiotic fungi in eucalypts. I'll dig up the reference tonight if you want a read I have some A.obtus seedlings that have reached a point where they have stopped growing, I use a light 1/4 to 1/2 strength seaweed fertilizer fortnightly. I am going to seed with a symbiotic fungi to see if this helps them. I will let you all know how it goes! Share this post Link to post Share on other sites
indigo264nm Posted April 19, 2006 Are those fertiliser pellets? (even if they are slow release)This might also be a problem. Over fertilization, too much of a particular nutrient. Acacia's like soils poorer in Nitrogen, generally. The "over-watering" would definitely not help either. Concider it when re-potting Good luck, and plant out as sson as appropriate. Slow release fert for native stock, only just added when repotted a few days before posting. It's not fert related. I'm putting it down to an attack from over watering and alot of heat this summer. I will put them next to the A. maidenii in the back yard. Share this post Link to post Share on other sites
transDiMenTional Posted April 19, 2006 (edited) How about for exotic acacia sp? Like for A.simplex for example? Does it use the same fungus as oz sp or a fungus native to where ever the sp is native to? I have noticed that out of all the acacias ive grown, simplex seems to need regular application of fert to remain green and pert.. hehe i just made a rhyme! sorta... edit: BTW this is all make believe cos growing non australian acacia sp is forbidden in oz i think...or so im told....so yeah, make believe! Edited April 19, 2006 by Alice Dee Share this post Link to post Share on other sites
foolsbreath Posted April 19, 2006 Like rev said the relationship isn't obligatory, so they don't depend on each other, but they are highly beneficial. Any likewise mycelium could be used I believe, Often its just a presence/absence that is included in studies, its likely 50% of the ECM's arn't even known to us! Share this post Link to post Share on other sites
planthelper Posted April 20, 2006 (edited) yep, fungi not bacterium as i said, my bad, sometimes i can't find the rigt term or i mix them up, ups a daisy. although i guess there are other liveforms in symbiosis with that fungi, which benefit the whole thing. Edited April 20, 2006 by planthelper Share this post Link to post Share on other sites
Rev Posted April 29, 2006 ECMs get all the publicity truth is and particularly with seedlings its the VAM ( or for modern terminolgy drop the V ) (Vesicular) arbuscular mycorrhizae are the main group of fungi that benefit seedlings and young plants in Acacia and eucalyptus ECMs take over later they wil be inadvertently innoculated with the rhizobium if you take soil from the rootzone of aheathy retalted acacia as fungal filaments are infective for about 10 days Share this post Link to post Share on other sites
occidentalis Posted April 29, 2006 (edited) Rev's on to it are the main group of fungi that benefit seedlings and young plants in Acacia and eucalyptusECMs take over later However in many cases young seedlings which have been inoculated actually grow slower than those without mycorrhizal associations at the start - it seems the fungus partner takes more than it's fair share of photosynthesis products at first. But they soon catch up and overtake their non-VAM'd brethren. they wil be inadvertently innoculated with the rhizobium if you take soil from the rootzone of aheathy retalted acacia as fungal filaments are infective for about 10 days And in my experience taking soil from healthy acacia rootzones has been very helpful when raising seedlings, particularly in commercial potting mix. But I would also relate this to rhizobium inoculation rather than mycorrhizae - just try and keep wild mycorrhizae out of a pot! I have without success. Any likewise mycelium could be used I believe, Often its just a presence/absence that is included in studies, its likely 50% of the ECM's arn't even known to us! Some do have highly specific relationships, others are general. One reason why it's just a presence/absence thing is because they're real bastards to ID. But yeah if you feel like discovering a species microfungi are the way to go... a mate of mine has just described two new fungal foliar pathogens of eucalypts. It's a matter of a walk in the bush and a (lengthy) microscope session. Edited April 29, 2006 by creach Share this post Link to post Share on other sites
foolsbreath Posted April 29, 2006 Good stuff guys! It was this site that piqued my interest in fungi again, and I am now involved in a research project on ECM fungi and Vam's, so hopefully I'll get round to putting sum stuff in a greenhouse and measuring results with different fungi etc (probably next year). At present I am looking into the relationship between mychorizal species richness and abundance and the health of estabished trees and vice versa Share this post Link to post Share on other sites
Rev Posted April 29, 2006 (edited) be prepared for any result thats the world of fungi Edited April 29, 2006 by Rev Share this post Link to post Share on other sites
