Sunday, January 20, 2013

Apical shoot deformity in Melia dubia (Malai Vembu, Konda Vepa, Hebbevu) plantations:

Dear Friends,

Melia dubia (Malai Vembu, Konda Vepa, Hebbevu) is now in lime light only because of its tremendous initial growth i.e., during first two years even in marginal soils with sparse irrigation. Its growth after that initial period vastly differs from field to field and the current field reports are not that much encouraging in many parts of Tamilnadu, Andhra and Karnataka states.

Growth variation is so huge that even in my field, girth increment of some 4 year old trees are 200% more than 8 year old trees. Since too much hype has been generated already, reality will sink in slowly and in the coming years farmers will come to know about the type of soil required, soil depth, climate, tolerance to maximum temperature, drought tolerance and water requirement for successful cultivation of Melia dubia.   

Though drought tolerance of this tree is moderate, it becomes ‘stunted’ during prolonged droughts. Tree will shed all its leaves and the growth stops during extreme and prolonged hot conditions. Do not plant in Alkaline soil, clay, sodic soils and wherever there is poor soil depth. Melia grows well in irrigated (weekly once) soils where pH is below 7.5.

All the plants in a field will not grow uniformly and the trees planted in bunds and near water channels exhibits rapid growth and attain enormous girth within 4 - 5 years. The presence of this kind of + trees though in small percentage are brought to centre stage by ruthless traders to make quick money. The pictures and Videos of young yet enormous Melia trees you find in 'Net' are carefully selected picks from the above +trees among a vast lot of average plants. So, don’t get distracted and be realistic in your estimates as the law of averages will always come to play even in your field.
‘Apical shoot deformity in Melia dubia’:
I happened to notice in my field last year that apical tip (actively growing top most tip of a plant) of about 5% to 8% of my Melia trees were found to be deformed. On closer examination I could not able to see any pest infestation (bore hole) leading to canker or any fungal infestation. In the later months I happened to see the same mysterious deformity in many parts of Tamilnadu and Karnataka states. I showed this condition to CCF and ACCFs of Forest Extension Department in their own demo plots itself in various districts.

The affected tree exhibits no vertical growth and for identification purpose I named it as ‘Apical shoot deformity in Melia dubia’. The affected plant part is usually about 1.5 to 2 feet, swollen, black in colour, rigid, one third of the length curved like a sickle or coiled.  A tree planted in my backyard first showed this deformity about 2 years back. Now, the growing tip of lower most side branch of the same tree is also got affected.

Picture of deformity in side branch:

At the time of my visit to Forest College Research Institute (FCRI), Mettupalayam, Coimbatore, Tamilnadu on May, 2012, I pointed out the same deformity of apical tip in some Melia dubia trees  (2 %to 3%) in their demo plots also that had not been observed by them earlier. The photos I had with me at that time were not good (long shots) so requested the FCRI people to take close up shots since they have a very high portable aluminum ladder to reach the tree tops easily. I fervently hoped that with all the correct persons, knowledge, equipment and lab, FCRI can find the reason and suggest a remedy which will definitely benefit poor ‘Melia tree grower’. After continuous follow up I came to know that exact cause of this condition is still not identifiable and they are also receiving same complaints from many Melia fields in T.N.
Then I happened to hear from few scientists of Institute of Forest Genetics and Tree Breeding Institute (IFGTB), Coimbatore that they have also observed this when they visited some pest infested Melia fields (Melia plantations affected by ‘Stem borers’ and ‘root grubs’) for on the spot assessment. According to them the scale of ‘Apical shoot deformity’ is up to 10% in some fields and their initial studies have revealed that this attack is neither due to insect nor due to fungus. Lab tests were going on to assess whether this is a viral infection since severely infected plots are located adjacent to fields with gourd family (Cucurbitaceae) vegetables which are a major source of virus pathogens.
Let these research institutions come with their findings at their leisure. We can not blame them since they don’t have virus testing facilities in their labs and even If they identify the cause for this deformity it has to be proved scientifically, has to be documented, corroborated by senior scientists before press release.

May be this deformity is due to physiological or environmental factors also. I kindly request our knowledgeable readers and ‘Melia growers’ to come out with their view. May be some of you might have invented cure for this infection. Speak out !, since you are the correct person to judge the cause and suggest remedy for this mysterious ‘Apical shoot deformity in Melia dubia’.


A.Vishnu Sankar

12 Comentários:

Dr.G.Kumaravelu said...

Dear Mr.Vishnu shankar.
Thanks for sharing your observations.So far i had not seen the problem stated by you .I will keep this in mind,visit,discuss with knowledgeble Melia dubia farmers and share my thougts on this with you..
With wishes.

Dr.N.Krishnakumar, IFGTB said...

Dear Mr Vishnu shankar
I had seen this deformity in Melia some 4 months before when as a team we visited some melia plantations of various age gradations in Erode, Nammakal and other areas .we have got into serious work on this aspect.more views on this are welcome as called for by you.please keep in touch.
Dr. N. Krishna Kumar
Institute of Forest Genetics and Tree Breeding
Coimbatore- 641 002

S.A.Alagarsamy Sornam, Sivakasi. said...

i never had a young tall tree along with Mahua and Neem and sappota tres all together in my land..
Now Melia has outgrown all of them and it is tall.
i was so surprised that even among stiff competition Melia tubia grows well
in my farm

Guru said...

Hi Vishnu,

Your blog is exceptionally good for people like and has lot of valuable information.

A quick question from me - Do you know of any trusted suppliers of Melia Dubia saplings around Villupuram?

Also is there some schemes from either State or Central Government for Melia Dubia plantation, drip irrigation etc?

Thanks -- Guru!

Vishnu Sankar A said...

Dear Friend,

Thank you for visiting this blog. Referring nurseries will spoil the image of this blog. As a policy I have never referred any nursery to anybody to avoid misunderstandings.

Through 'Tamilnadu Biodiversity Conservation and Greening Project' you can get seedlings free of cost from the Forest Extension Division of your district. As of now Drip irrigation subsidy is not available for raising Timber plantations. But farmers are availing the benefits by first going for any vegetable cultivation particularly gourds that usually requires spacing as that of Melia and after getting subsidies they will move to Melia cultivation, sometimes both the crops at the same time if the officer agrees.

Best wishes.

Thanking you,

Yours friendly,
A.Vishnu Sankar

Pravin said...

Dear Sir,

Can you please let me know whether Malai Vembu cultivation will be good in CLAY Soil lands.

Vishnu Sankar A said...

Dear Friend,

Malai Vembu will not come well in clay soils. No doubt in it. Don't attempt even for experimentation / trial purpose also.

Approach experts with your farm soil test report with details of clay content and the depth of clay in the soil strata.

Sathyanarayana M R said...

Dear Sir,

I have 34 gunta land near Nelamangala, Bangalore. It is dry land which does not have any water source and right now used only for growing Ragi crop. Can I go for Hebbevu cultivation in this land? Please suggest.

Vishnu Sankar A said...

Contract farming in plywood:
View this link:

Gj said...

Hello sir, can you please post the latest photos? How is the growth of both the trees?

Anonymous said...

sir,what is the current position of that problem

Anonymous said...

Hi Sir,
I have 6 acres of land and it is Black soil. is Malai Vembu will grow in black soil? Kindly suggest


  ©Template Blogger Green by Dicas Blogger.