Articles
DISORDERS IN FLOWER AND FRUIT DEVELOPMENT IN TOMATOES AT LOW TEMPERATURES AND DIFFERENT LEVELS OF SHADING
The effect of temperature and light intensity on prediction of fruit set and fruit development was investigated.
The results indicated that fruit deformation occurs in winter-grown tomatoes as a consequence of abnormal flower development under low-temperature conditions.
It also occurs under low light intensity in both cool and warm seasons.
Differences in varietal susceptibility to the various types of malformation were also detected.
Fruit faciation as a result of deformations in various flower organs, was very frequent in tomato oblate fruited cultivars with a large number of locules (cv.
Orith), but not in globe fruited cultivar (cv.
Arava). Other types of fruit deformation that also stem from low temperature conditions at the time of flower development, appeared in both cultivars and consisted of either navel-like or scarlike aberrations at the blossom-end.
Low temperature during flowering affected seedless fruit development.
In the semi-determinate flattened globe fruited "Hosen-Eilon", flower and fruit malformation increased with the intensity of shade and was enhanced by low temperatures.
Similarly, pollen viability decreased with shading.
Style elongation above the stamens was more frequent during the warm season.
For the indeterminate globe fruit cultivar "Viresto", malformation and style protuberance was rare and shading had no effect on its occurence.
Cultivation of tomatoes in the winter season without heating or under insufficient light intensity requires careful choice of cultivars to suit these special conditions.
The degree of flower deformation (mainly ovary) and pollen viability could be used as an index to assess the potential rate of fruit set and shape of fruit which may develop.