Question
Hi, i am vivek from India.i have heard that cow's urine is very good for trees. Somebody has told me that cow's urine can be sprayed over apple trees for preventing diseases.can it be possible what contains cow's urine.guide me.

Answer
Odd but true: Cow urine is indeed a biopesticide. There is even a name for it: Panjakavyam.  ("5 ingredients", i.e., Cow urine ("komiyum"), Cow manure, curd, ghee and milk.  The Neem Foundation goes into a great deal of detail about research about various organic treatments on farms in India:

www.neemfoundation.org/neem-articles/neem-updates/vol-v-no-4/keeping-up-with-neem.html

Why cows, and not horses?  sheep?  alligators?  rabbits?  dogs?  deer?

Well, it appears that this technique is widely practiced in India.  Cows have a special place in the Land of Ghandi.  They are not held in quite the same esteem in the West, where they are mere livestock, along with sheep, goats, horses, etc.

It is not therefore something unique about Cow urine that drives this recipe.  It is the social rank of the Cow and the availability of the product, in my opinion.

This is not to say that Cow urine is identical to the urine of other livestock.  But I don' tthink it is as significant a difference as you find when you compare the composition of different animal Manures.

Manure nutrients vary significantly in ratios of NPK depending on the animal, reflecting the diet of the animal and the metabolism of the animal.  Cow manure is different from horse manure.  All manure is rich in Nitrogen, with varying amounts of Potassium, Phosphorus and micronutrients.  Cow manure is 25-15-25 fertilizer.  Compare that ratio to manures of Chicken is 11-8-5; Horse, 70-30-60; and Rabbit, 24-14-6.

But mammal urine is pretty much Urea, water and miscellaneous hormones, with traces of non-absorbed minerals from the day's breakfast.  I cannot be more specific because I don't have a chemical analysis of each of these handy.

The 'Fun with Pee' website actually claims that there is a theoretical drink called 'Cow Water' (Gua Jal) for human consumption, ostensibly because 'Cow urine has been considered by some Hindus as a way to purify the body and treat sickness.' Here's their URL:

www.urinecolors.com/fun_with_pee.php

I guess at this point I should insert a legal disclaimer here: do not try this at home.  But not all of us have access to a Cow.

But seriously, folks, the use of Cow urine in various concoctions is indeed not only a Nitrogen-packed spray on fertilizer but a natural and free (if you have a Cow) alternative to bug spray.  Researchers have actually been studying various formulas to document the results on different crops and different insect pests.  Example: The Journal of Aphidology, put out by the Aphid Society of India, posts results of a study in 2008, 'Bioefficacy of Cow Urine Decoctions of Botanicals against Mustard Aphid and Coriander Aphid.'  The Mustard Aphid died; the Coriander Aphid didn't.

It's not as simple as you think.  One formula I came across works because the insect larvae hatching on a leaf so sprayed are repelled and ultimately die of starvation.  It doesn't kill on contact.  It makes the leaf unpalatable.

That said, I confess I am not THAT familiar with the practice of spraying with any kind urine, Cow or otherwise, as a disease preventative.  It makes sense however that if you succeed in reducing or eliminating the up-close-and-personal incidence of attack by pathogen-carrying vectors, you sharply reduce the chances your plants will get sick.  And that, as Martha would say, is a good thing. Mooo!