Ethylene is involved in maintaining tomato (Solanum lycopersicum) pollen quality under heat-stress conditions
Open Access
- 1 January 2012
- journal article
- research article
- Published by Oxford University Press (OUP) in AoB Plants
- Vol. 2012, pls024
- https://doi.org/10.1093/aobpla/pls024
Abstract
Exposure to higher-than-optimal temperatures reduces crop yield and quality, mainly due to sensitivity of developing pollen grains. The mechanisms maintaining high pollen quality under heat-stress conditions are poorly understood. Our recently published data indicate high heat-stress-induced expression of ethylene-responsive genes in tomato pollen, indicating ethylene involvement in the pollen heat-stress response. Here we elucidated ethylene's involvement in pollen heat-stress response and thermotolerance by assessing the effects of interfering with the ethylene signalling pathway and altering ethylene levels on tomato pollen functioning under heat stress. Plants of the ethylene-insensitive mutant Never ripe (Nr)—defective in an ethylene response sensor (ERS)-like ethylene receptor—and the corresponding wild type were exposed to control or heat-stress growing conditions, and pollen quality was determined. Starch and carbohydrates were measured in isolated pollen grains from these plants. The effect of pretreating cv. Micro-Tom tomato plants, prior to heat-stress exposure, with an ethylene releaser or inhibitor of ethylene biosynthesis on pollen quality was assessed. Never ripe pollen grains exhibited higher heat-stress sensitivity, manifested by a significant reduction in the total number of pollen grains, reduction in the number of viable pollen and elevation of the number of non-viable pollen, compared with wild-type plants. Mature Nr pollen grains accumulated only 40 % of the sucrose level accumulated by the wild type. Pretreatment of tomato plants with an ethylene releaser increased pollen quality under heat stress, with an over 5-fold increase in the number of germinating pollen grains per flower. Pretreatment with an ethylene biosynthesis inhibitor reduced the number of germinating pollen grains following heat-stress exposure over 5-fold compared with non-treated controls. Ethylene plays a significant role in tomato pollen thermotolerance. Interfering with the ethylene signalling pathway or reducing ethylene levels increased tomato pollen sensitivity to heat stress, whereas increasing ethylene levels prior to heat-stress exposure increased pollen quality.Keywords
This publication has 34 references indexed in Scilit:
- EGY1 plays a role in regulation of endodermal plastid size and number that are involved in ethylene-dependent gravitropism of light-grown Arabidopsis hypocotylsPlant Molecular Biology, 2007
- Effects of season-long high temperature growth conditions on sugar-to-starch metabolism in developing microspores of grain sorghum (Sorghum bicolor L. Moench)Planta, 2007
- Adverse high temperature effects on pollen viability, seed-set, seed yield and harvest index of grain-sorghum [Sorghum bicolor (L.) Moench] are more severe at elevated carbon dioxide due to higher tissue temperaturesAgricultural and Forest Meteorology, 2006
- Pollen grains of heat tolerant tomato cultivars retain higher carbohydrate concentration under heat stress conditionsScientia Horticulturae, 2006
- Thermotolerance and antioxidant systems in Agrostis stolonifera: Involvement of salicylic acid, abscisic acid, calcium, hydrogen peroxide, and ethyleneJournal of Plant Physiology, 2004
- Glass formation in plant anhydrobiotes: survival in the dry stateCryobiology, 2004
- Super‐optimal temperatures are detrimental to peanut (Arachis hypogaea L.) reproductive processes and yield at both ambient and elevated carbon dioxideGlobal Change Biology, 2003
- Pectin secretion and distribution in the anther during pollen development in LiliumPlanta, 2001
- A new model system for tomato geneticsThe Plant Journal, 1997
- Occurrence of mono- or disaccharides and polysaccharide reserves in mature pollen grainsSexual Plant Reproduction, 1997