• PSHTWAN J. M. AL-ZEBARI Dept. of Horticulture, Akree Technical College, Duhok Polytechnic University, Kurdistan Region-Iraq
  • TAHA Z. SARHAN Dept. of Horticulture, Akree Technical College, Duhok Polytechnic University, Kurdistan Region-Iraq
Keywords: Foliar spray:, Licorice Root Extract:, Humic Acid,Yield:, Summer Squash:


Field experimentwas indicated at the experimental vegetable farms, college of agriculture, Duhok University,Kurdistan region-Iraq during the spring growing season of 2018, to evaluate the impact of licorice root extract (0, 5, 10 g.L-1) and humic acid (0, 2, 4 g.L-1) as foliar exerciseon yield traits of summer squash (Cucurbita pepo L.) (cv.Naji F1).These experiments were laid out in a factorial arrangement in randomized complete block design(F-RCBD) with three replications.The results of this experiment showed that foliar spray of squash plants with licorice root extract at 10g.L-1 recorded highest value in most of yield traits and in terms the early yield (0.389kg.plant-1) was significantly increased. Moreover, spraying plants with humic acid atlevel 2g.L-1 the yield characters of squash plants was significantly increased in traits of early yield (0.383 kg.plant-1)and marketable yield (34.86 ton.ha-1), while humic acid spray at level 4g.L-1 significant affect on fruit number (13.81), fruit length (14.14 cm), fruit diameter (3.65cm),  average fruit weight (123.41gm), total yield (1.707 kg.plant-1) and total yield (39.61ton.ha-1), except the unmarketable yield (4.656 ton.ha-1) were decreasedwith increasing the level of humic acid.In addition, the combination treatments between licorice root extract at 10g.L-1 and humic acid at 4g.L-1 gave the highest value in the most of yield parameters in studied summer squash plants


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How to Cite
AL-ZEBARI, P. J. M., & SARHAN, T. Z. (2020). EFFECT OF LICORICE ROOT EXTRACT AND HUMIC ACID ON YIELD CHARACTERS OF SUMMER SQUASH (Cucurbita pepoL.). Journal of Duhok University, 22(2), 49-60. https://doi.org/10.26682/ajuod.2019.22.2.5
Agriculture and Veterinary Science