Evaluation of low cost techniques in potted vegetables grown in roof gardens

Abstract

A pot culture study was conducted at the College of Agriculture, Vellayani to evaluate the lowcost techniques in potted vegetables and to compare the efficiency of various techniques for economising water use in vegetables. The experiment was conducted with chilli cultivar ‘Jwalasakhi’ as test crops. The treatments included three levels of irrigation (I3-60, I2-80 and I1-100 per cent field capacity), two methods of irrigation (M1- indigenous auto irrigator using hospital drip and M2-pot watering) and three moisture conservation methods (c0-control without any conservation, C1-application of coir pith and c2-application of Jalasakhti). One absolute control viz., wick irrigation was compared with other treatments. Potting mixture prepared by mixing sand, soil and cowdung in 1:1:1 proportion by weight was used as the rooting medium. The medium was low in available nitrogen, high in available phosphorus and low in available potassium. The field capacity and permanent wilting point were 18.4 and 7.4 per cent respectively. The experiment was laid out in completely randomised design with six replications. The results of the investigation are summarised below. Plant height, branches, LAI at harvest, DMP, S: R ratio and root dry weight at different growth stages differed significantly with methods, levels of irrigation and conservation methods. All these parameters were better under wick irrigation, 100 per cent FC and coir pith mulching. Whereas drip irrigation recorded maximum LAI at initial stages and tap root length. All yield parameters like number of flowers plant-1, fruit plant -1, fruit girth, fruit volume and hundred fruit weight were better under wick irrigation followed by drip irrigation. Among the moisture regimes 100 per cent FC registered better values for all the yield attributes. Coir pith mulching top seeded with respect to these characters. Maximum yield was obtained for wick irrigation, 100 percent FC and coir pith mulching. With respect to WUE, coir pith mulching followed the same pattern as yield. Whereas drip irrigation recorded maximum WUE and 80 per cent FC resulted in higher WUE compared to the other two irrigation regimes. Uptake of N, P and K were maximum in wick irrigation and coir pith mulching. N and K uptake were maximum at 100 per cent FC, but P uptake was high at 80 per cent FC. Under all levels of irrigation, maximum yield and WUE were obtained by drip irrigation and coir pith mulching. Coir pith mulching revealed its superiority under both methods of irrigation with respect to yield and WUE. Maximum yield was obtained at drip irrigation at 100 per cent FC with coir pith mulching while maximum WUE was obtained at drip irrigation at 80 per cent FC with coir pith mulching. Maximum profit was realised by drip irrigation at 100 per cent FC with coir pith mulching. With drip irrigation and coir pith mulching 20 per cent water can be saved without much reduction in yield.