Approximately 0.4 to 0.5 kg fresh, tender branches of Cleistanthus collinus are planted erect or spread in the standing water after establishment of summer rice with the anticipation of pest outbreak. This practice is being followed by a good number of farmers belonging to Kapgari village under Jhargram subdivision in Midnapur district of West Bengal. This practice has been in vogue over generations without any modification and is being followed in patches vulnerable to insect-pest incidence. Rice gundhi bug generally appears in damaging level during rainy (kharif) season in the early maturing varieties that mature during 1st or 2nd week of October
Results and discussion
Experiments were conducted during the rainy (kharif) seasons 2002, 2003 and 2004 at CRRI, Cuttack and during kharif 2002 and 2003 in farmers’ field of Ajodhya village, Balasore (Odisha). In farmers’ fields, only 3 treatments each with 10 replications were taken, i.e. implanting parasi twigs, applying insecticides and untreated control. Results obtained from the experiments conducted at CRRI, Cuttack and in farmers’ fields during 2002 revealed that gundhi bug infested the paddy in spite of parasi application. But there was decrease in population for the treatment where it was applied after infestation and applied as fresh twigs or leaves. Accordingly, the yield was also highest in the treatment. But a significant increase in yield was not obtained in parasi treatment than in untreated control. Experiments conducted during 2003 showed that insect incidence was less and irregular in farmers’ fields. Parasi twigs were implanted when the insect population was 1/m2 , but it did not increase subsequently, as is clear from the data on 10 DAT. However, insect population was found to decrease in parasi treatment in comparison to untreated control. Yield was also more though not significant. Yield data during 2003 were much influenced by rain and subsequent flood. Hence these have not been presented.
Gundhi bug population was reduced by both fresh leaves and planting of twigs of parasi at the time after gundhi bug infestation.