I am thankful to this retired professor Dr. Thomas Varghees of soil science from Kerala Agricultural University for the complete remedy of "Brown bast" Disease.The guidance of Dr. Thomas Varghees helped a farmer to prove the solution of brown bast through his experiences and experiments which is not find out by any of the scientists in the World. This scientist recommended the importance of organic matter to maintain the soil live. This finding is pointing out the need for participatory inventions through the co-opertion of scientistis and farmers. The disease is not detectable because the first cells to undergo necrosis are located in internal tissues of the bark. Dr. Thomas varghees's right hand points the level of bark island ring around the tree (insted of bark island) which is an indication of the begining of phloem necrosis. The physiological disorder is due to the deficiancy of nutrients/trace elements.
The picture at right hand side is regarding a rubber tree which is treated for Brownbast/TPD OR phloem necrosis. This tree was afected approx 10 years ago. I tried  'cut ' (Controlled upward tapping) on it and applied diluted ethephon to regulate the flow from top to bottom (actually flow of latex is bottom to top above phloem. Phloem carries carbohydrates from leaves to the roots to grow) which cause complete dryness on Bark. On upper bark, approx 10 ft hight, tapped with the help of ladder which gave me good yield. Lot of time is wasted in this process. I applied magnesium sulphate to soil with bio gas slery. I saw a visible change in the bark colour to greenish by a scratch, but no milk vessels formed which was dry up to Cambium. Then I applied slery with 10 grams of Borax on dried part of the stem didn't saw a visible change. By depthening the mark at the end of tapping pannel (pinkaana) latex flow was in the upper portion and not available from 5 ft hight to bottom. Last year I applied 10 grams of borax with 30 litres of bio gas slery on soil around the tree and again marked the pinkaana with to see progress of the availability of latex vessels up to 3 ft hight after three months. This year (on last week) I started tapping and getting an average yield with minimum coagulants, which means driping for 4 hrs. Thus the Tapping interval increased according to dripping. I have to bring the required coagulants to drip below three hrs. Unfortunately by tapping on 8 days intervals I got 1000 ml latex  on each day and driping more than 8 hours which was harmful to the tree. Thus  another micro nutrient zinc sulphate (by the guidance of Dr. Thomas Varghees ) diluted with coconut oil aplied on new bark  to regulate dripping. After 3 days by removing lace scrap I saw all the milk vessels are closed with a thin cap to stop the flow of latex. And the observation is a need for a good result.
From my experiences by the application of Ethephon (Stimulant) on 334 rubber trees 65 of them caused brown bast.  After two years of low frequency tapping effects of brown bast increased.  Now Indian Rubber Board published and article in Malayalam on "Ethephon application on rubber trees - apprehension baseless" which is harmful to rubber trees. The brown bast affected trees are with live bark with out carbo hydrates in phloem or milk vessels. After the application of 10 grams of BORAX milk vessels formed on brownbast  affected trees after one year. On punches on pinkaana I saw the availability of latex up to the bottom level which is shown at the right hand side: In conclusion I have to state that Brown bast is a disease which can be treated with required input of specific micro nutrients.
An imges of a book on the roll secondary nutrients and trace elements. There can be no doubt that a deficiency of boron causes more loss of yield and growth inhibition than a deficiency of any other trace element. To read more >>>> Borax, also known as sodium borate, sodium tetraborate, or disodium tetraborate, is an important boron compound, a mineral, and a salt of boric acid. It is usually a white powder consisting of soft colorless crystals that dissolve easily in water. In agriculture it can be used as a fertilizer to correct boron-poor soils; however, it is required in small amounts. Excess can cause injury to plants. Ref:- http://en.wikipedia.org/wiki/Borax Borax available in the market like commercial purpose which is cheaper approxmately Rs. 57.50/- and the above mentioned on is costly up to Rs. 170/-.