EFFECTIVENESS OF RELATIVE WATER CONTENT AS A SIMPLE FARMER’S TOOL TO DETERMINE PLANT WATER DEFICIT

Abstract

Cabbage (Brassica oleracea var. capitata L.) is a botanically and commercially important vegetable cultivated all year round in the tropics. Although cabbages are easily grown under a wide variety of conditions and are adaptable to most climatic conditions, successful cultivation of this crop is hampered by incidences of water stress. To produce quality acceptable heads that are marketable, supply of right amount of water is paramount. To monitor whether the plants are getting enough amount of water there is need to use a reliable, simple, and indicative method. Relative water content has been proposed as a simple tool that could be employed with ease and precision by a farmer. To test the effectiveness of Relative Water Content (RWC) as a simple farmer’s friendly parameter, cabbage variety Pruktor and Michel F1 (potted) were subjected to four treatments in two seasons. The treatments were: 0%, 25%, 50% and 100% of soil field capacity arranged in a complete randomised design. Samples to determine RWC were collected in three day intervals. Water stress did not affect head formation but decreased growth, leaf area, head size, and total yield. In both experiments, yellowing and selective shedding of leaves was observed mostly in 0% and 25% treatment. Relative water content declined significantly with day after treatment and decreasing water supply. Among the control, plants with lower RWC had smaller head compared with those of relatively higher RWC. This indicates RWC as a simple parameter that could be used to monitor water status of the plant during growth to enhance production of good quality marketable head and maintain crop yield.