MSc

Investigations were carried out during two seasons (October-January, 1981-82 and March-May, 1982) to find out the response of 20 Cucumis genotypes to four levels of ethephon (0,100, 200 and 300 ppm) at the Instructional Farm, College of Horticulture, Kerala Agricultural University, Vellanikkara. Ethephon caused significant reduction in length of main vine, nodes to first female flower, nodes to first fruit, seed number and flesh thickness. Nodes to first male flower and primary branches/plant were significantly increased. There was no significant effect of ethephon on fruit length, fruit weight and fruit volume during both the seasons. There was an increase in yield in CS 27 (326.62%) while definite reduction in yield was observed in CS 26 (42.53%), CS 43 (60.47%), CS 38 (60.79%), CS 51 (50.74%) and CS 31 (63.82%) during the first season. During second season there was no significant effect of ethephon on fruit yield.
Effect of ethephon sprays on plant to alter vegetative characters is further confirmed in the present study. Despite reduction in seed number due to ethephon application, no appreciable change was observed for fruit weight, fruit volume and fruit length. This is a matter for worth investigation.
Reduction is vine length and increase in primary branches could be attributed to effects of ethephon to effect the phenomenon of apical dominance. The study proved that response of Cucumis genotypes to ethephon is governed by genotype, season of cultivation and concentration of ethephon used.