Effect of foliar application of putrescine on growth, yield and fruit quality of sweet pepper

In order to study the effect of putrescine on growth, yield and fruit quality of Sweet pepper (Capsicuum annum cv. Dimaz) under water stress, an experiment was conducted in split plot based on randomized complete block design with three replications in research filed of university of Zanjan. Treatments consisted of three irrigation levels (50, 75 and 100% ETc) and putrescine including four levels (0 (control), 0.5, 1 and 1.5 mM). The results showed that water deficit stress reduced growth and fruit yield of sweet pepper .The highest growth, fruit number, yield and vitamin C content was obtained in irrigation 100% ETc and TSS in 75% ETc. Foliar application of putrescine improved growth and fruit yield. The highest plant growth, plant height (67.00 cm), leaf area (5887.28 cm2), chlorophyll content (2.2 μg /g), plant dry weight (29.41 ETc), vitamin C (42.67 mg/100ml), fruit chlorophyll (0.18 μg /g), fruit length (16.56 cm), fruit number (268.00), fruit yield per plant (0.45 kg) and total yield per hectare (9.98 ton) was obtained with foliar spray of 1.5 mM putrescine under 100% ETc irrigation. According to the results, application of 1.5 mM putrescine can be proposed to improve growth and fruit yield of pepper under water deficit stress.