MSc

An experiment was conducted during 1995-96 in the Department of
Olericulture, College of Horticulture, Vellanikkara to catalogue and identify
promising ashgourd ecotypes in relation to season and maturity.
1birty ecotypes of ashgourd were studied for their variability. The
experiment was laid out in randomised block design with three replications. High
heritability along with high genetic gain was observed for the characters primary
branches per plant, fruit yield per plant, seeds per fruit and average fruit weight.
Yield was positively and significantly correlated with length of main vine, nodes on
main vine, primary branches per plant, internodal length, leaves per plant at 30 days
after sowing, male flowers per plant, female flowers per plant, per cent of female
flowers, average fruit weight, fruits per plant, percent of fruit set, circumference of
fruit, length of fruit, seeds per fruit and 100 seed weight. Average fruit weight
exhibited the highest positive direct effect on fruit yield per plant.
The ecotype BH 21 possessing highest values for characters like length of
main vine, number of nodes, number of female flowers, fruit yield per plant and
number of seeds per fruit was selected to study the effect of sowing time and
periodicity of harvests on yield. This experiment was laid out in split plot design
taking months of sowing as main plot treatments and intervals of harvesting as
subplot treatments.
All biometric characters were significantly influenced by the sowing time.
The crop sown in October was superior to other crops with regard to number of



nodes, earliest node at which the first female flower was formed and fruit retained,
number of female flowers, per cent of female flowers, number of fruits per plant,
number of seeds per fruit and fruit yield per plant. In general the crops sown during
August, September and October performed better in yield contributing characters
when compared to the crops raised during other months of the year.
The plants under the harvest interval of 14 days produced the highest
number of female flowers and fruits per plant. Average fruit weight, circumference,
fruit shape index, flesh thickness and number of fully developed seeds were highest
for fruits harvested at full maturity. Though more number of fruits were obtained
from plants' under a harvest interval of 14 days the highest yield in terms of total
fruit weight was realised from plants harvested at full maturity.
The crop was succumbed to the attack of pests and diseases throughout
the year. Fruit fly infestation was severe in April, May and June sown crop.
Incidence of pumpkin beetle was severe 111 February, March, April and May sown
crop. Mosaic was severe 00 crops sown in November, December, January and
February. June and July sown crops exhibited downy mildew disease. The better
expression of yield contributing characters and lower incidence of pests and
diseases tor the crops sown during August, September and October indicated that
these months are most ideal for raising a crop of ashgourd.
The crop weather relationship revealed that maximum temperature during
first and second weeks after anthesis had a significant positive correlation with' yield
at full maturity. Minimum temperature and sunshine hours also have a positive
correlation though not significant. A negative correlation exist between relative
humidity and yield.