Impact of Applied Nitrogen Concentration on Growth of Elatior Begonia and New Guinea Impatiens and Susceptibility of Begonia to Botrytis cinerea

Abstract

<jats:p>Plant performance and appearance in deficient and toxic levels of nutrients are well characterized. However, less is known about the potential subtleties of plant growth, form, development, nutrient uptake, and biotic stress tolerance in the broad tolerable range. Begonia [Beg (<jats:italic>Begonia</jats:italic> × <jats:italic>tuberhybrida</jats:italic> Voss)] and new guinea impatiens [NGI (<jats:italic>Impatiens hawkeri</jats:italic> Bull.)] were grown over a wide range of N (from 1.78 to 57.1 m<jats:sc>m</jats:sc> NH<jats:sub>4</jats:sub>:NO<jats:sub>3</jats:sub> ratio at a 1:1 ratio supplied as nutrient solution) in a peat:perlite soilless substrate in greenhouse conditions. Plant growth, development, chlorophyll content, leaf angle, nutrient uptake, tissue caloric value, and susceptibility to <jats:italic>Botrytis cinerea</jats:italic> Pers.:Fr. disease were evaluated in two experiments. Elevated N supply resulted in decreased plant height (16% in Beg and 7% to 16% in NGI), flower count (3% to 48% in Beg and 7% to 49% in NGI), bud numbers (23% to 80% in Beg), canopy area (11% to 33% in NGI), and mass (21% to 33% in Beg and 18% to 58% in NGI). Chlorophyll content saturated at an N supply of 28.6 m<jats:sc>m</jats:sc>. N uptake efficiency, shoot N use efficiency, and shoot N utilization efficiency decreased with increasing N supply. Elevated levels of N supply from 7.15 to 57.1 m<jats:sc>m</jats:sc> also increased the susceptibility of Beg to <jats:italic>B. cinerea</jats:italic> disease by 10% to 80% in stems and 3% to 14% in leaves. The increase in susceptibility also corresponded with increased tissue energy content (kJ·g<jats:sup>−1</jats:sup>) and altered leaf orientation. This study indicates many plant changes occur between nutrient extremes that can have a significant impact on growth, development, and the ability to withstand disease.</jats:p>

Airborne fungi associated with ornamental plant propagation in greenhouses

“…It was reported to cause serious losses in [200 crop species worldwide (Williamson 2007). Greenhouse crops are among the major hosts of B. cinerea (Friedrich et al 2005;Pitchy et al 2007). In both greenhouses, visible colonies of B. cinerea with fully developed conidiophores and conidia were found on begonia, zonal geranium, fuchsia, and New Guinea impatiens.…”

Contrasted responses of Botrytis cinerea isolates developing on tomato plants grown under different nitrogen nutrition regimes

“…, 1998), sweet basil (Yermiyahu et al. , 2006) and begonia (Pitchay, 2007). In three of these studies (R’Houma et al.…”

“…, 1998; Yermiyahu et al. , 2006; Pitchay, 2007), the N source was nitrate or a mixture of nitrate and ammonium. In contrast, a high N nutrition seems to lower the level of disease in tomato (Verhoeff, 1968; Hoffland et al.…”

Growth, Partitioning, and Nutrient and Carbohydrate Concentration of Petunia ×hybrida Vilm. Are Influenced by Altering Light, CO2, and Fertility

“…No difference in flower timing or development rate was observed with any variables. In other species, higher N supply has delayed flowering (Díaz-Pérez et al, 2003;Pitchay et al, 2007;Powell et al, 1988;Smith et al, 1998). In our study, all nutrients were increased, not just N, which may have mitigated any influence additional N had on development rates.…”

“…Fertility, light, and CO 2 are other environmental factors that can be manipulated within a greenhouse that influence growth and development. For example, Klock-Moore and Broschat (2001) showed a 20% increase in petunia growth when supplied with 50% additional nutrition from overhead irrigation [100 mgÁL -1 nitrogen (N) increased to 150 mgÁL -1 N], but generally, additional N can delay or suppress flowering (Díaz-Pérez et al, 2003;Pitchay et al, 2007;Powell et al, 1988;Smith et al, 1998). Kaczperski et al (1991) modeled petunia growth and development in a combination of light and temperatures and found strong effects of both.…”