Abstract:
Field study on the effect of alternate growing systems and irrigation schedules for
soilless culture of salad cucumber under drip irrigation was conducted inside the
naturally ventilated polyhouse in the research plot of Precision Farming
Development Centre, in the Instructional Farm of KCAET, Tavanur, during
November 2013 to March 2014. In this study coirpith was the media used. The
crop water requirement of salad cucumber was determined using CROPWAT
model. The data on micro climate inside the polyhouse were periodically recorded
on daily basis.
The physico chemical and engineering properties of coirpith were studied. The
experiment was laid out in a two factor completely randomized block design. The
plot was divided into three rectangular sections with three treatments each
replicated thrice. The treatments were F1T1 (Black poly bag with daily irrigation),
F1T2 (Black poly bag with alternate day irrigation), F1T3 (Black poly bag with
irrigation once in 3 days), F2T1 (Lay flat grow bags with daily irrigation), F2T2
(Lay flat grow bags with alternate day irrigation), and F2T3 (Lay flat grow bags
with irrigation once in 3 days).
Fertigation in coir pith include both macro and micro nutrients applied as
water soluble fertilizers from two tanks (tank A and tank B) through fertigation
system with venturi. Data about vegetative parameters for each treatment were
observed during different stages of crop growth. The results on the effect of
alternate growing systems used, irrigation frequency and their combined effect on
crop growth and yield parameters were statistically analyzed. Analyzing the effect
of alternate growing systems, it was found that vertical type growbag filled with
coirpith showed better performance than lay flat type growbag. In case of
irrigation interval, crops under once in three days irrigation showed better
performance at the initial stage (winter season). But during mid-season (summer
season) alternate day irrigation resulted in better growth and yield than once in
three days irrigation. The highest yield was for F1T2 (7.56 kg/plant) followed by
F1T1 (6.34 kg/plant).
Irrigation interval significantly affected irrigation water use efficiency
(IWUE). The highest IWUE was for F1T3 (2590 kg/ ha.mm) and lowest was for
F2T1 (446.14 kg/ ha.mm). Even though crops under alternate day irrigation were
identified with remarkable yield, once in three days irrigation can be suggested in
the areas experiencing water shortage.
The results of this experiment showed that it is possible to obtain
satisfactory yields of hybrid cucumber Hilton variety grown under polyhouse
conditions in coirpith filled vertical growbags. The study also revealed that crops
with once in three days irrigation at initial stages followed by alternate day
irrigation during mid-stage and late stage in vertical type growbag resulted in
better performance. Using inert growing media like coirpith demands full
fertigation with all macro and micro nutrients for good FUE.