METHOD: Reproductive Efficiency CONDITIONS: Lab - 21C METHOD NARR: Two experiments were done. The first (GH) test determined reproductive efficiency through egg counts. See separate entry. The second (in vitro) test determinedf the blb clones grown under sterile in vitro culture conditions. Roots were infected with hatched second-stage juveniles and allowed to grow for 55 days. The number of eggs was counted and used to generate a reproductive eNATION: There was sufficient correspondence between screening methods for Race 1 to promote the use of in vitro screening to identify resistance in a breeding program. The lack of concordance for Race 2 detracts from this vieion of R factors by egg counts was the only criterion usable for host response.