Biology of seed transmission of Erwinia stewartii in maize

Abstract

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Quantifying the Feeding Periods Required by Corn Flea Beetles to Acquire and Transmit Pantoea stewartii

“…Early reports suggested that seed transmission played an important role in the occurrence of Stewart's disease (24,30). However, recent studies by Michener et al (18), Block et al (2)(3)(4), and Khan et al (12) all have shown that the risk of seed-to-seedling transmission of P. stewartii is extremely low. In their study, Khan et al (12) grew 75,000 plants from seed that was harvested from P. stewartiiinfected plants and did not find any seedto-seedling transmission of P. stewartii in the test plants; however, they did not determine the actual percentage of P. stewartii-infected (or infested) seed.…”

“…Isolate stability was confirmed by serial transfers onto nonselective media and by plant inoculation and re-isolation. No evidence of back mutation was observed (2). Prior to inoculation, cultures were incubated for 48 h at 25ºC on nutrient broth yeast extract agar (NBY) amended with cycloheximide (100 µg/ml), rifampicin (50 µg/ml), and nalidixic acid (40 µg/ml (NBY-CRN).…”

“…Michener et al (18) reported that seed-toseedling transmission was 0.038% after testing 58,300 kernels obtained from infected plants. Studies by Block et al (2)(3)(4) revealed only 0.14% seed-to-seedling transmission of P. stewartii from infected kernels harvested from artificially inoculated plants (29 of 19,735 seed), and 0.022% (1 of 4,563) seed-to-seedling transmission from P. stewartii-infected kernels harvested from naturally infected plants (3).…”

“…In their study, Khan et al (12) grew 75,000 plants from seed that was harvested from P. stewartiiinfected plants and did not find any seedto-seedling transmission of P. stewartii in the test plants; however, they did not determine the actual percentage of P. stewartii-infected (or infested) seed. Both Michener et al (18) and Block et al (2)(3)(4), however, adjusted their estimates of seedto-seedling transmission to account for the percentage of infected seed in a seedlot. Michener et al (18) reported that seed-toseedling transmission was 0.038% after testing 58,300 kernels obtained from infected plants.…”

Status and Recent Developments of Pantoea stewartii subsp. stewartii Causes the Wilt Disease in Maize in Indonesia: A Review

“…Then in 1962 based on the similarity of its physical properties. Pathogenic bacteria changed their name to Erwinia stewartii (Smith) (Lamka, 1990;Block, 1996;Cushatt, 2020). Some of these name changes were made based on the morphological and physiological characteristics of the pathogen.…”