Scaffolds 01 index

(Art Agnello ama4@nysaes.cornell.edu & Harvey Reissig whr1@nysaes.cornell.edu, Entomology, Geneva)

Obliquebanded leafroller moths started flying in the Hudson Valley on June 4 and in Wayne Co. (Marion) on June 7, which puts us back on a nearly normal schedule for insect activity for the time being. First hatch is generally assumed to occur about 360 DD (base 43 F) after the flight starts, and we'll be updating you each week with values for Highland and Geneva. This brings us quite naturally to the perennial question of how best to approach management of OBLR populations this year, so a brief synopsis of last year's research efficacy trials might be in order.

Pesticide control programs for the first summer brood of OBLR were conducted in two Wayne Co. orchards in 2000, one of them an Empire/Cortland mixed planting, and the other McIntosh/Idareds. All sprays were applied using some of the following timings after the beginning of summer adult flight on 6/11: Peak Flight (6/20), First Hatch (6/27, the standard 300 DD timing), 40% Hatch (7/5) and "cover sprays" at various timings: 7/11, 7/19, and 7/24.

- Confirm 2F and Intrepid 2F (the 2nd-generation version of Confirm) were applied at 6/20, 7/5 and 7/19.

- A large group of products and combinations were compared at 6/27, 7/11, and 7/24: Asana XL, Lorsban 50WP, Baythroid 20WP (cyfluthrin, a pyrethroid), SpinTor 2SC, Proclaim 5SG (emamectin benzoate, an avermectin) combined with either Dyne-Amic or Kinetic, DiPel DF, Lepinox (another B.t. formulation), and Avaunt 30WG combined with other products (SpinTor, DiPel 2X, and Asana).

- A later SpinTor 2SC program was applied on 7/5, 7/19, and 7/31.

- Avaunt was applied in a seasonal program on 6/20, 6/27, 7/5, 7/10, 7/19, and 7/24.

The initial infestation levels were quite low in both orchards, compared with those observed the previous season. Fruit damage in the untreated check plots at harvest (4.8% at the Empire/Cortland site and 11.0% at the McIntosh/Idared site) was also low. Average fruit damage levels in the combined orchards were generally less than 3% in plots treated both with the most effective newer compounds and older standard materials. All rates of Intrepid, Proclaim combined with Dyne-Amic and the high rate of Baythroid were the most effective treatments of new compounds in both orchards. The standard materials, DiPel and Lorsban, also allowed less than 3% damage. The synthetic pyrethroids, Asana and Baythroid, were relatively more effective in the McIntosh/Idared block than in the Empire/Cortland plot. Neither Avaunt nor the various mixtures of compounds tested with this material (Spintor, DiPel and Asana) were as effective as the better standard insecticides, SpinTor, Lorsban, and DiPel. Fruit damage was higher in the Lepinox plots than in the standard DiPel treatments. The SpinTor treatment applied at the later timing was no more effective than the standard 300 DD timing.

Our recommendations for OBLR management this year continue to follow along lines similar to those we have given previously. Most materials available should be at their maximum potential effectiveness when used 2-3 times (in moderate or high pressure orchards, respectively) against the first summer brood larvae. Applications in a 3-spray program should be made at times approximately corresponding to periods of first hatch, mid-hatch, and 2 weeks after mid-hatch. In orchards where SpinTor is being used, the inclusion of a low rate of an adjuvant such as LI-700 or Sil-Wet is recommended. As always, standard materials such as Asana and SpinTor are likely to work better against populations not having a history of extensive exposure to them.

Disease 6.11