  This factorial experiment was conducted in a greenhouse during the period of
May 3, 2021 to August 5, 2021 at the research farm belongs to the Horticulture
Department, College of Agricultural Engineering Sciences, University of
Sulaimani, Sulaimani, Iraq. The experiment was designed to study the effect of
some biostimulants, individually and their combinations, on cucumber plants
performance under greenhouse conditions; in addition to compare the results
with of chemical fertilizers application. The treatments consisted of control
(without adding any kinds of biostimulants) recommended dose of 100% chemical
fertilizers (RDCF), seaweed extracts (SE), moringa leaf extract (MLE),
bacterial-based biostimulant of Fulzym-plus (FP), that contains Bacillus
subtilis and Pseudomonas putida, (SE+MLE), (SE+FP), (MLE+FP), and (SE+MLE+FP).
The experiment was laid out in simple RCBD with 3 replications. The results
showed that the application of different biostimulants, individually and their
combinations, significantly improved the root growth characteristics. However,
the highest values of lateral roots number per plant, lateral root length,
lateral root diameter and root system dry weight were recorded by the
application of recommended dose of chemical fertilizer (RDCF). While, this
treatment was not different substantially with the triple combination of the
tested biostimulants (SE+FP+MLE) in all studied root characteristics. In
addition, untreated plants registered the minimum value of all the mentioned
characters.
