Management of Insecticide Resistant Helicoverpa armigera Lepidoptera: Noctuidae) in Cotton in India

Helicoverpa armigera (Habner) was responsible for some $500 million of damage in India in the 1997-8. Insecticide resistance levels have been monitored routinely at sites throughout the countl)' since 1992 using discriminating dose assays. Resistance to pyrethroids is ubiquitous and stable at around 50-80% in most areas. Organophosphate and endosu(fan resistance is stable at around 20-50%. Carbamate resistance is low. There is-...(. ll:.rrently no significant resistance to Bt. Putting in place effective, economic, insecticide-based programmes that do not exacerbate the resistance problems, is a priority. Field trials from 1992-5 at 1CR1SAT developed appropriate 1PMI1RM practices in pigeonpea Clnd cotton. In 1995-6 these were takell illto 'split-plot' 1PMIIRM farmer trials in Andhra Pradesh (AP). Seed cotton yields were slightly enhanced with a 23% reduction in the number oj insecticide sprays and a 57% reduction in the a.i. applied. In expanded trials in 1996-7 trials in AP and Tamil Nadu, insecticide use was reduced by over 40% and yields enhanced by 30%. Components of the package included appropriate varietal selection, seed quality and agronomy and improved spraying practices with quality materials based on scouting to simple economic thresholds. Early season spraying for sucking pests was avoided by the use of systemic seed dressings. The sequence used for bollworms was: Eggs: at low numbers - neem; at high numbers - profenojos, Larvae: 1st round: endosulfan; 2nd round OPs (quinalphos or chlorpyrifos); 3rd round,' carbamates (carbaryl); 4th round - pyrethroids (cypermethrin, fen valerate. deltamethrin or lambda cyhalothrin). In the 1997-8 season farmer participatol)' demonstrations were undertaken in four states (Punjab, Andhra Pradesh, Maharashtra and Tamil Nadu). In all areas spray applications were at least halved with respect to non-participating farmers' and yields rose by at least a third. The work was expanded in the 1998-9- season

Developing and implementing insecticide resistance management practices in cotton ICM programmes in India

Pyrethroid, organophosphate, carbamate and cyclodiene resistance levels for the cotton bollworm (Helicoverpa armigera) have been monitored routinely at sites throughout India since 1993 using discriminating dose assays. Resistance by H. armigera and other pests to commonly used insecticides is a severe constraint to cotton production in India. An integrated crop management strategy was developed aimed at maximising profit while minimising insecticide use and the impact of insecticide resistance. Appropriate varieties and agronomy, plus seed treatment where necessary, allow the first foliar insecticides to be delayed until at least 70 days from planting. Insecticides for fruit and leaf feeders are then rotated, taking account of seasonal shifts in their efficacy and the pest spectrum faced; with endosulfan first, followed by particular organophosphates, leaving one to two pyrethroid sprays until the late season when pink bollworm is also present. This system (customised for the different regions of India) was demonstrated in village participatory trials, reaching 24 villages across four states in 1998-9. In all areas the quantity of insecticide a.i. used was reduced by >29%; yields increased substantially and net profit rose $40 to$226/ha when compared with farmers not in the schemes

Mealy Bugs In Cotton And Their Management

Not AvailableMealy Bugs In Cotton And Their ManagementNot Availabl

Not Available

Not AvailableNot AvailableNot Availabl