Effect of interrupted leaf wetness periods on pustule development of Puccinia recondita f. sp. tritici on wheat

Abstract

In growth chamber experiments, seedlings of a susceptible wheat cultivar (Rubis) were inoculated with urediospores of wheat leaf rust. Inoculated seedlings were incubated in a moist chamber. The period of exposure to leaf wetness varied in duration and progressed with or without one or more interruptions of variable duration. During the interruptions the leaves with germlings were dry. At near-optimal temperature, leaf wetness periods of six h resulted in 60 to 65~ of the pustules produced with 12 or 24 h wetness periods. Interruption of a 6 h leaf wetness period by a 1 h dry period was most damaging to the rust germlings at about three to four h after inoculation. The damage became visible as a reduction in the number of resulting pustules and as a prolongation of the median latency period. Epidemiological implications of leaf wetness interruptions are discussed.

Overwintering and epidemiology of Puccinia dracunculina, the causal agent of rust in open tarragon fields

“…Spore germination, as affected by weather conditions, is an important factor affecting the development of rust diseases (Stuckey & Zadoks, 1989; de Vallavieille‐Pope et al. , 1995; Furuya et al.…”

The Infection of Soybean Leaves by Phakopsora pachyrhizi during Conditions of Discontinuous Wetness

“…Reductions in the infective capacity under discontinuous wetness were also observed in other pathosystems for fungi that cause rust and other diseases including Puccinia recondita f.sp. tritici (Stuckey and Zadoks 1989; De Vallavieille‐Pope et al. 1995), P. striiformis on wheat (De Vallavieille‐Pope et al.…”

Role of Weather Factors and Wheat Varieties on the Occurrence of Leaf Rust of Wheat in Satna, M.P. India

“…Since, the LR of wheat has intimate relation with weather factors (temperature, relative humidity and winter rainfall)which were obtained from observatory of AKS University and were calculated as mean; maximum, minimum temperatures and relative humidity (RH) of February (third and fourth weeks) and March (first, second & third weeks) 2019 and 2020 (Table 1). These weather data were used in the establishment of relationship with development of LR disease by Nagarajan and Joshi (1978a); Stubbs et al, (1986); Stuckey & Zadoks (1989); Singh et al, (2002); Riaz, et al, (2013); Marsalis and Goldberg (2017).…”

“…1985;Bahadur, et al, 1994).Instead of dispersal of LR the amount of precipitation and number of rainy days also play an important role in disease development (Nagarajan and Joshi,1978a;Singh & Tiwari,2001). The requirement of minimum, maximum and optimum temperatures for the germination of uredospores, growth of germ tubes, formation of appressoria, penetration and formation of sub stomatal vesicles have been best studied by many plant pathologists (Stubbs et al, 1986;Stuckey & Zadoks, 1989;Singh et al, 2002;Riaz et al, 2013;Marsalis and Goldberg 2017). Leaf wetness and latent period is another factor for LR disease development (Stuckey & Zadoks, 1989;Riaz et al, 2013;Marsalis and Goldberg 2017).…”

“…The requirement of minimum, maximum and optimum temperatures for the germination of uredospores, growth of germ tubes, formation of appressoria, penetration and formation of sub stomatal vesicles have been best studied by many plant pathologists (Stubbs et al, 1986;Stuckey & Zadoks, 1989;Singh et al, 2002;Riaz et al, 2013;Marsalis and Goldberg 2017). Leaf wetness and latent period is another factor for LR disease development (Stuckey & Zadoks, 1989;Riaz et al, 2013;Marsalis and Goldberg 2017). Number of hours with temperature between 5 to 25°C and relative humidity >87% are highly correlated and predicts LR infections with 89% accuracy.…”