Irrigation management related to sub-surface moisture conservation techniques in oriental pickling melon

Abstract

An experiment was conducted in the summer rice fallows during 1996 at Agricultural Research Station, Mannuthy to study the irrigation management related to sub-surface moisture conservation techniques in oriental pickling melon. The experiment was laid out in randomised block design with three replications. The treatments consisted of combinations of four moisture conservation techniques (control, incorporation of sawdust, paddy waste and coir pith @ 1/3rd pit volume) and four levels of irrigation (IW/CPE ratio of 0.4, 0.8, 1.2 and at critical stages). The study revealed that incorporation of moisture conservation materials increased the growth attributes like length of vine, number of leaves per vine, leaf area, leaf area index and dry matter production and yield attributes like length, girth, weight of fruits and number of fruits per plant. Among the moisture conservation materials paddy waste was found to be the best for incorporation followed by coir pith. The increase in the number of fruits per plant and yield per hectare over control was 30 and 27 per cent respectively by paddy waste incorporation, whereas for coir pith incorporation this increase was 13 and 17 per cent respectively. Oriental pickling melon responded very well to irrigation. Biometric characters (length of vine, number of leaves per vine, leaf area, leaf area index, drymatter production) and yield attributing characters (length, girth, weight of fruits and number of fruits per plant) were favourably influenced by frequent irrigations. The fruit yield increased with increase in frequency of irrigation and was maximum at IW/CPE ratio of 1.2. The interaction effect was found to be significant on growth attributes and yield. It also indicated that the significant effects of moisture conservation materials were pronounced only at closer intervals or irrigation (IW/CPE 0.8 and 1.2) and were more pronounced at the activity growing stages ie. after 45 DAS. Incorporation of moisture conservation materials increased the soil moisture content, consumptive use and water use efficiency. Total consumptive use increased with increase in irrigation frequency. Drier regimes showed a tendency to extract more moisture from deeper layers. The peak consumptive use and crop coefficient were reached maximum between 36-50 and 51-65 DAS respectively. Soil moisture extraction pattern showed that oriental pickling melon on an average depleted 50.7 per cent of the total water use from the top 15 cm layer. Field and crop water use efficiency were higher in less frequently irrigated treatments. N,P and K content of the leaves were enhanced by frequent irrigation and incorporation of paddy waste. Incorporation of paddy waste and coir pith increased the net profit to the tune of 68 per cent respectively over control. Scheduling irrigation at IW/CPE ratio 1.2 was economically better than other irrigation treatments. The combination of moisture conservation techniques and levels of irrigation further increased the net profit and net return per rupee invested over the individual effects. Best net profit was obtained when the crop was irrigated at the IW/CPE ratio of 1.2 with the incorporation of paddy waste. If water is scarce for irrigation, incorporation of paddy waste or coir pith and irrigation at IW/CPE ratio 0.8 was highly beneficial than crops at the closer interval of IW/CPE ratio 1.2 without any moisture conservation material.