A laboratory study supported with field observations was done on the life cycle, the effect ofrnphysical' and edaphic factors on the development of Pachlloda illlel'l'upla (Oliver) (rnColeoptera: Scarabaeidae). The food preference and factors contributing to extended diapausernof the adult were also included in the study. The laboratory study was conducted at fourrndifferent temperature regimes (20, 25, 30 and 35Â°C) and four soil moisture levels (9, 17, 23rnand 29%). Soils collected from Afar, Tikur-Inchini, Guder River near Ambo were usedrnseparately and mixed with different propOliion of cow-dung to note its effect on laralrndevelopment. Based on the information obtained fi'om fanners in the infested area eight typesrnof food substances were tested for their effect as bait. In the life cycle study (at 25Â°C & Moisture 17%) the average oviposition rate was fOllnd to bern0.58 eggsl day/ female. Whitish soft shelled eggs were laid separately in soil varying (strata)rnfrom 3-18 cm. in depth. The mean number of incubation days of egg was 9.63Â±1.4 rangingrnbetween 8 and 13. Larval development took an average of 59.09 Â± 1.94 days ranging betweenrn42-73. Body length was constantly increasing till around 52 days where it reached 30.2 m111rnand was shrinking latter and measured 28mm at about the 70th day. Larval head capsulernwidth, however showed discontinuolls; but constant increase and at an average 3.14Â±0.0Immrnwas measured in final days (62-70). Pupal development ranged fi'om 18-30 days with anrnaverage of24.47 Â±3.5 days. The depth of pupation site was found to be dependent on moisturernlevel. When soil moisture is less the larvae went down deep in to the soil to pupate and whenrnit is high, they remained in the upper layers. Soil temperature however did not showrnsignificant effect on pupation depth. The adults required an average of 93.79Â± 1.8 days,rnranging from 68-116 to emerge. The laboratory study and the field observation confirmed that P. interl'llpta are univoltine insects but the adults have two phases (emerging seasons). Thernfirst phase emerges directly from pupa, and it is non reproductive and worst pest of crops suchrnas sorghum and maize and enters in to the soil for diapausing for about nearly 8 months. Thernstable temperature in the soil especially under tree shades, food reserve p31iicularly fatrncontributes for long lasting diapause. This emerges as second phase synchronized with rainsrnand flowering of non crop plants such as Acacia spp., and this is the reproductive phase.rnBeetles of this phase feed mainly on flowers, mate, lay egg in the soil and die The presence of cow-dung in the soil was found necessary for completion of the life cycle.rnThe cow dung serves the larvae as food. and essential for growth, however when itsrnconcentration increased exponentially, the growth rate decreased, but the total life cyclernshortened. Soil moisture and temperature have also shown significant effects on percentagernsurvival and developmental rate. Moisture levels of 17 and 23%were found to be morernimportant as compared with moisture regimes beyond and below these. Temperature of 25rnand 30Â°C were found to be very essential for survival of larvae and for the completion of liferncycle. Among the eight food substances tested as bait, ripe banana was most preferredrnfollowed by ripe guava. Residues of local beer, 'tej' and 'katicala', roasted maize andrnsorghum flour were preferred next while non-roasted sorghum flour was the least preferred.