-10- 



The use of beneficial bacteria to promote establishment and 

 growth of young trees is a new area of research. Spectacular bio- 

 logical control of crown gall, caused by the bacteria Agrobacterium 

 tumef aciens , has prevented the stunting and poor growth associated 

 with the gall formation on crown gall-infected trees. An organism 

 from New Zealand has been reported by the USDA and plant pathologist: 

 at Agricultural Experiment Stations to promote favorable growth of 

 fruit trees. Dr. A. Jones, MSU plant pathologist, is using New 

 Zealand bacteria Agrobacter radiobacter (isolate #84) to inoculate 

 tree roots by dipping at planting time as well as inoculating the 

 soil in an attempt to promote growth of young fruit trees in Michi- 

 gan by preventing crown gall infection. 



The exact mechanism of activity by the organism is not known. 

 Some pathologists believe the isolate occupies sites on the plants 

 and thus prevents other pathogenic bacteria from, invading the plant 

 root system. 



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TARNISHED PLANT BUG ON APPLE: DAMAGE AND MONITORING TRAPS 



Ronald J. Prokopy, Karen I. Hauschild, and Roger G. Adams 



Department of Entomology 



The tarnished plant bug (TPB) is among the 5 most injurious 

 insect pests of apple fruit in Massachusetts orchards. 



From the published literature, we know that TPB adults over- 

 winter under duff in hedgerows. During the first warm days of 

 Spring, they begin flying into apple orchards. There, an adult 

 seeks out a developing flower bud, inserts its beak into the bud, 

 and sucks up plant sap. After the beak has been removed, sap oozes 

 from the puncture, sometimes forming a large, readily visible drop- 

 let. The overwintering adults continue to feed in this manner until 

 they die, usually by the time of the first cover spray. The adults 

 rarely lay eggs in apple trees but rather in legumes and other ground 

 cover plants. Indeed, some of our preliminary findings suggest that 

 a large amount of vetch, alfalfa, a clover in or near the orchard may 

 encourage substantial buildup of TPB populations. The eggs hatch into 

 nymphs, which then give rise to second generation adults. The nymphs 

 do not feed on apple. Neither, apparently, do the second and third 

 generation adults -- at least not to the extent of causing noticeable 

 injury. 



Research on TPB was initiated in 1976 because we wanted to learn 

 more about this insect. Our goals were three-fold: (1) to determine 

 what types of apple injury result from TPB feeding, and when these 

 injuries are initiated; (2) to develop some sort of simple, effective 

 monitoring method for estimating the size of TPB populations in apple 



