Zamioculcas loddigesii, Zamiacaulcas zamiafolia, Zamioculcas lanceolata, Z.
Advanced Search Abstract To determine the thermosensitive periods and physiological processes in tomato flowers exposed to moderately elevated temperatures, tomato plants Lycopersicon esculentum Mill. The same level of stress did not significantly reduce fruit set when applied immediately after anthesis.
The same level of stress relief for 3—24 h after anthesis also increased fruit set. Microscopic investigation of anthers in plants grown continuously at high temperature indicated disruption of development in the pollen, endothecium, epidermis, and stomium.
This disruption was reduced, but still observable in plants relieved from high temperature for 10 d before anthesis. Introduction For many species, reproductive processes appear to be much more sensitive to temperature stress than vegetative growth.
Differential temperature sensitivity for reproductive and vegetative growth have also been reported in soybean Baker et al.
Because of this sensitivity of reproductive processes, predicted temperature increases of 0. The cause of this enhanced or hypersensitivity of reproductive development to even moderate levels of high temperature stress is not well understood.
In many crops, not only is the reproductive process more sensitive to high temperature stress than vegetative growth, but within the development of an individual flower, certain stages are also more sensitive. In groundnut, the number of pegs and pods per plant were significantly reduced by high temperature, by duration of exposure, and by timing of exposure.
In wheat, the period of microsporogenesis is also sensitive to other environmental stresses, such as drought Saini and Aspinall, ; Sheoran and Saini, ; Lalonde et al. The duration and timing of the sensitive period during microsporogenesis and immediately after pollination was not reported in either of these studies, however.
Also, the developmental process leading to the failure of pollen release and the reduction of pollen viability was not described. The purpose of the present experiments was to determine the critical duration and timing of moderately elevated temperature stress which is likely to be experienced under global warming and to analyse anther tissue microscopically to determine whether critical periods of sensitivity to moderately elevated temperature stress were correlated with particular developmental lesions during microsporogenesis.
Another question was whether plants react similarly to the imposition and relief of the stress. Materials and methods General procedures Tomato plants Lycopersicon esculentum Mill. NC Gardner, were used. Plants were seeded in a gravel: Seedlings were transplanted 15 d after sowing DAS to 6 cm diameter pots ml in volume filled with gravel: Natural light was supplemented by incandescent lights from Seedlings were transplanted to 20 cm diameter pots 4.
Day temperatures and light regimes began at Flowers were examined daily from 45 DAS to determine when they were 5 d before anthesis. When buds in most of the plants assigned to a particular treatment period were at stage iii—iv Sawhney and Bhadula,plants were moved into treatment chambers.
In all treatments, when a fully opened flower was found, a pollinating rod was applied to the flower cluster for a few seconds to assist pollination, as is standard practice in controlled environment tomato production Picken, The flower was then tagged by date.
An average of three flowers were pollinated and tagged on each plant during the course of the experiment. Since tomatoes flower sequentially within a single inflorescence and continue to produce inflorescences as they develop, a single temperature exposure treatment affects flowers at different developmental stages.
All pollinated flowers were tagged on the day of anthesis, and the dates of the start of each temperature treatment were known, so it was possible to determine the developmental stage at which that particular flower had been exposed to high temperature relief or imposition.
At 98 DAS, all tagged flowers, pedicels and fruit were counted. Experiment 2 The purpose of this experiment was to investigate the effect of relief and imposition treatments imposed immediately after anthesis on pollen germination, pollen tube growth and fertilization.
The 32 MS plants in each growth chamber were divided into four groups consisting of eight plants each. General procedures for Experiment 2 have already been described.
Temperature treatments were started immediately after pollination of all flowers. In each treatment, pollination procedures described below was started at The 12 h treatments took place over 9 h of the light period and 3 h of the dark period.Effects of solar radiation and temperature in different periods before and after anthesis on yield of tomato (Solanum lycopersicum) in summer greenhouse cultivation were investigated.
Fluctuations in yield were caused mainly by the variation in fruit number rather than fruit weight. Number of species: Click on thumbnail photo for a larger version of image. Click on the scientific name for additional photos and information. Temperature is a primary factor affecting the rate of plant development.
Warmer temperatures expected with climate change and the potential for more extreme temperature events will impact plant productivity. Plants were grown at 21/16°C and some (W) were warmed, between 10 and 20 days after anthesis, to 33/25°C and then returned to 21/16°C where they stayed until maturity.
predict the developmental stage of tomato (Lai et al., ). Furthemore, there is a study in which the optical properties of fresh cut tomato at different stages of development was evaluated (Lana et al., ).
Also, color determination in tomato epicarp at room . The aim of this work was to compare methods to predict the time of anthesis in tomato (Solanum lycopersicum L.). Two independent experiments were carried out using seeds of the Tauro commercial.