Contribution of leaf growth on the disappearance of fungicides used on tea under South Indian agroclimatic conditions.
The sprayed chemicals on tea leaves disappear over a period of time by the influence of rainfall elution, evaporation, growth dilution, and photodegradation. Influence of plant growth on the four fungicides (hexaconazole, propiconazole, tridemorph, and c) was studied to know the constructive loss of fungicides. The study shows that residues of fungicides sprayed on tea shoots got diluted by the growing process. The expansion of a leaf took 8 to 11 d and more than 50% of the fungicide residues were cleaned out during this leaf expansion period. Under south Indian agroclimatic condition, the fungicides are sprayed at an interval of 10 d, so it is safe that the tea is harvested on the 10th day of the application of fungicides.
Karthika
Chinnachamy
C
United Planter's Association of South India (UPASI) Tea Research Institute, Tea Research Foundation, Nirar Dam B.P.O, Valparai 642 127, Tamilnadu, India. kartheecm@rediffmail.com
Muraleedharan
Narayanan Nair
NN
D028241:Camellia sinensis / Q000737:chemistry* / Q000254:growth & development*; D002980:Climate; D005659:Fungicides, Industrial / Q000032:analysis* / Q000737:chemistry*; D007194:India; D018515:Plant Leaves / Q000737:chemistry* / Q000254:growth & development*
D005659:Fungicides, Industrial