Boron Nutrition and Chilling Tolerance of Warm Climate Crop Species

Abstract

Background Field observations and glasshouse studies have suggested links between boron (B)-deficiency and leaf damage induced by low temperature in crop plants, but causal relationships between these two stresses at physiological, biochemical and molecular levels have yet to be explored. Limited evidence at the whole-plant level suggests that chilling temperature in the root zone restricts B uptake capacity and/or B distribution/utilization efficiency in the shoot, but the nature of this interaction depends on chilling tolerance of species concerned, the mode of low temperature treatment (abrupt versus gradual temperature decline) and growth conditions (e.g. photon flux density and relative humidity) that may exacerbate chilling stress.Scope This review explores roles of B nutrition in chilling tolerance of continual root or transient shoot chills in crop species adapted to warm season conditions. It reviews current research on combined effects of chilling temperature (ranging from >0 to 20 C) and B deficiency on growth and B nutrition responses in crop species differing in chilling tolerance.Conclusion For subtropical/tropical species (e.g. cucumber, cassava, sunflower), root chilling at 10-17 C decreases B uptake efficiency and B utilization in the shoot and increases the shoot : root ratio, but chilling-tolerant temperate species (e.g. oilseed rape, wheat) require much lower root chill temperatures (2-5 C) to achieve the same responses. Boron deficiency exacerbates chilling injuries in leaf tissues, particularly under high photon flux density. Suggested mechanisms for B · chilling interactions in plants are: (a) chilling-induced reduction in plasmalemma hydraulic conductivity, membrane fluidity, water channel activity and root pressure, which contribute to the decrease in root hydraulic conductance, water uptake and associated B uptake; (b) chilling-induced stomatal dysfunction affecting B transport from root to shoot and B partitioning in the shoot; and (c) B deficiency induced sensitivity to photo-oxidative damage in leaf cells. However, specific evidence for each of the mechanisms is still lacking. Impacts of B status on chilling tolerance in crop species have important implications for the management of B supply during sensitive stages of growth, such as early growth after planting and early reproductive development, both of which can coincide with the occurrence of chilling temperatures in the field.

Boron Deficiency in Soils and Crops: A Review

“…Warncke (2005) observed the amelioration of internal black spot in cranberry bean seed with B application. Boron nutrition of cereal crops in connection to chilling tolerance has also been demonstrated by Huang & Ye (2005). Problems like stunning of cotton growth, wilting of the plants and reddening of cotton leaves have been observed in the major cotton growing areas of Sindh province in Pakistan.…”

Boron fertilizers borax and colemanite application on rice and their residual effect on the following crop cycle

“…The interaction between fertilizer and rate was not significant. Huang et al (2005) claimed that B requirement for reproductive growth is much higher than for vegetative growth and its deficiency at the flowering stage can cause sterility and flower malformations. Borax and PC fertilizers were equal in efficiency because of the longer time in the soil PC was able to supply sufficient B to the crop.…”

Carências de boro no interior - norte e centro - de Portugal

“…Além destes, a intensidade luminosa também é mencionada, em vários estudos, como agente potenciador da sensibilidade das plantas à escassez de B (Bell, 1997;Cakmak e Römheld, 1997), por induzir maiores crescimentos e, por essa via, também aumenta as exigências deste micronutriente. Por outro lado, Huang et al (2005Huang et al ( , 2007 referem que a escassez de B agrava os estragos provocados pelas geadas tardias, particularmente em locais onde a intensidade luminosa é elevada.…”

“…As encostas quentes sugerem-nos que tanto se poderá tratar duma alusão à forte radiação que ocorre no Douro nas encostas expostas a sul, associada a taxas de crescimento elevadas, ou a uma maior secura do terreno. Pode ainda estar relacionada com o fenómeno designado de geadas de radiação, que propiciam maior sensibilidade das plantas à escassez de B (Marschner, 1995;Shorrocks, 1997) e aos danos provocados pela geada (Huang et al, 2005), às quais também Le Cocq (1894) se referiu.…”