Adverse effect on plants cause of spraying of pesticides.
It is of two kinds :
1. Permanent phytotoxicity leading to the death of the effected part or whole plant
2. Temporary phytotoxicity which allows the plant to recover after showing phytotoxicity
Most insecticides are not phytotoxcity at ordinary concentrations temporary / permanent phytotoxcity when applied indiscriminately at much higher concentrations.
Eg: Now many farmers are applying insecticides formulations as ULV sprays which are meant for application as higher volume sprays.
Some times the solvents/diluents used may also cause phytotoxcity However, some plants/crops are highly sensitive to certain insecticides and show phytotoxicity when applied.
Symptoms of phytotoxicity
- Chlorosis or yellowing of leaves
- Bronzing of leaves
- Necrosis of complete plant or parts of it
- Deformation and curling of leaves
- White spots on leaves
- Burning effects on leaves
- Premature falling of leaves
- Mottled leaves
- Poor germination of seeds
Organo chlorines – Curcurbits
Carbaryl – Soybean & Redgram
Dimethoate and Malathion – Sorghum
Methyl parathion – All Cucurbits
Sulphur- Crcurbits, Apples and Tea