EFFECT OF ORGANIC GROWING SUBSTRATES AND SELENIUM ON FRUIT QUALITY AND YIELD OF STRAWBERRY CULTIVARS IN HYDROPONIC CULTURE

Abstract

Executive Summary The choice of appropriate growing substrates is an important factor in promoting the optimum growth of crops, like strawberry plants. Mixing of coarser materials with growing substrates at different ratio can improve the physicochemical properties of growing substrates. Selenium is another important mineral for human health. The content of selenium in strawberry can be increased by application of selenium during cultivation. Therefore, an experiment was carried out to evaluate the physicochemical properties of the organic growing substrate mixture and their influence on growth of the plant and yield of strawberry cultivars with application of selenium in hydroponic system. Treatments considered four types of organic growing substrate mixtures (viz., M 1 = 60% rice husk + 30% coconut coir + 10% vermicompost, M = 60% coconut coi r+ 30% khoa + 10% vermicompost, M 3

72 2 = 60% sawdust + 30% khoa + 10% vermicompost, and M = 60% ash + 30% khoa + 10% vermicompost) four levels of selenium (viz., Se = 1.0 mg L -1 Selenium, Se 2 = 2.0 mg L -1 Selenium and Se 3 0 = 3.0 mg L = 0 mg L -1 Selenium) and three varieties (viz.,V 1 : Local Strawberry-1, V 2 :Local Strawberry-2 and V : Local Strawberry-3). Physicochemical properties of growing substrate mixtures and growth, yield, physiological traits, quality of fruits and phytochemicals of strawberry cultivars were measured. The highest pH (7.74) was found in M 4 3 which was not suitable for strawberry production while suitable pH (6.10) was found in M . Water holding capacity, air filled porosity and dry weights of substrate mixtures were higher in M 1 1 and lower in M .The highest plant height (26.16cm), number of fruits per plant (13.08), individual fruit weight (23.85g), fruit length (4.51cm), fruit diameter (4.14cm), fruit volume (22.23cc), yield per plant (321.8g) and ascorbic acid content (70mg/100g FW), TSS (16.14°Brix), total phenolic content (150.77mg/100g FW), total anthocyanin content (8.25mg/100g FW), total flavonoid content (5.97mg/100g FW) and selenium contents in fruits (1.63 mg/100g DW)were found in M 3 1 while the lowest in M . The highest number of fruits per plant (11.96), individual fruit weight (24.93g), fruit length (4.89cm), fruit diameter (4.26cm), fruit volume (20.38cc), yield per plant (305.95g), ascorbic acid content (68.12mg/100g FW), TSS (14.25°Brix) and selenium contents in fruits (3.28 mg/100g DW) were found in Se 3 and quality in Se 2 while the lowest in Se . The highest total phenolic content (139.37mg/100g FW), total anthocyanin content (7.44mg/100g FW) and total flavonoid content (5.0mg/100g FW) were found in Se 2. 0 The highest plant height (23.65cm), number of fruits per plant (14.13), individual fruit weight (25.70g), fruit length (4.61cm), fruit diameter (4.11cm), fruit volume (20.52cc), yield per plant (367.99g) and ascorbic acid content (70.41mg/100g FW), TSS (16.15°Brix), total phenolic content (150.14mg/100g FW), total anthocyanin content (8.63mg/100g FW), total flavonoid content (5.86mg/100g FW) and selenium contents in fruits (1.59mg/100g DW)were found in V 1 while the lowest in V 3 .Therefore, Se formulation can be used for fruit quality and Se 3 2 formulation can be used for growth and yield of strawberry cv. Local strawberry-1 along with M growing formulation in solid hydroponic system in Bangladesh