Insectisides.

[JungleBiker]

I am not an organic farmer but I think MF is being rather harsh on Chownah; we should be more open minded and learning from each other, not challenging each other to duels!

I understand MF's reasons for using chemicals and I appreciate his practical advice on which chemicals to use and how to apply them, but even without going organic the international trend is towards what is called integrated pest management (IPM) which relies on many different methods to manage pests including chemicals when necessary, but also biological, physical, genetic, cultural and other approaches. Taking this approach can reduce costs and therefore increase profits.

As for red spider mite, due to resistance to pesticides many millions of dollars of crops (and not all organic) in many countries around the world now use a predatory mite (Phytoseiulus persimilis) to control the red spider mites that attack many kinds of high value crops crops. I don't know if it is available in Thailand?

Papaya mosaic virus is probably the most devastating disease of papaya in Thailand and many other countries; it is very difficult (impossible) to prevent with spraying. So in Hawaii they have bred a variety that is resistant to the virus, but I think the new variety is a genetically modified organism and therefore may not be acceptable in some countries/markets (like Thailand). Also the variety is protected by patents so I doubt anyone could get seeds. Another solution (I don't know if this is financially viable) could be to grow the papaya in a screen house - i.e. covered with nylon netting of mesh size 32 (i.e. 32 threads per inch) to prevent the entry of the aphid vectors that transmit the disease. It may be viable if you can get higher prices for organic papaya?

MF's suggestion that organic farming is not commercially viable is simply not the case. There are now many millions of hectares of organic crops in the world today and the area is expanding rapidly. Many farmers are going organic not because they want to be environmentally friendly but because they can make more money. I understand that demand for certified organic produce far exceeds supply.

Hope you saw the article in yesterday's (7/7/07) Bangkok Post about organic asparagus farmers making good money; they are also happy not to be exposing themselves to toxic chemicals.

JB

[Lickey]

Thanks all for your informative replies, we sprayed all the infected plants,top to bottom with the insecticide MF recomemded, i then put 1 litre of washing up liquid in the irrigattion holding tank, this was delivered to the Papaya by 2 overhead sprinklers, 3 ground-level 10mtr radius sprinklers and 24 mini-sprinklers, The wind caught the spray from the over-head sprinklers and created some big bubbles, these just floated down and burst on contact,

Now, i really dont know if this has any bearing on the subject, but about 6 weeks ago, we planted 3rai of water melon and cucumber, these are already giving fruit, [also about 4 rai of maize,,, sweetcorn,] When we go to pick the cucumber about 7.30am there are swarms of ladybugs/birds on the big yellow flowers of the watermelon, am i thinking correctly here that the attraction of the flowers has bought the aphid eaters to the farm and therefore protecting future crops, Perhaps intercrop watermelon with taller plants? It certainly seems the Papaya is doing ok now, daily sales 1200bht, plus the other stuff,salad items ect, Seems like nature has found a way to help us all in the long run!!!

Cheers Lickey..