Metering device is a main component of vegetable transplanters that could save cost of operation and labour requirement in transplanting. Therefore, a tractor-drawn three-row automatic vegetable transplanter using an inclined magazine-type metering device for cylindrical paper pot seedlings was developed and evaluated in field. Experiments on metering device were conducted at seven forward speeds 1.0, 1.2, 1.4, 1.6, 1.8, 2.0 and 2.2 km/h, to determine the optimal performance speed for 45-day old tomato seedlings. Data on seedling spacing, tilted planting, soil cover, seedling damaged while conveying and feeding and transplanting were recorded and analysed for conveying efficiency (CE), feeding efficiency (FE), transplanting efficiency (TE), overall efficiency (OE) and seedling spacing (SS). The CE, FE, TE and OE were found to be 100, 83.3, 91.7 and 96.7%, respectively, at 1.2 km/h. The SS was ranged from 633 to 651 mm for speed range of 1-1.2 km/h. Based on the optimized values of laboratory studies, a tractor-drawn three-row automatic vegetable transplanter was developed and evaluated in the field. The field performance data revealed that actual field capacity of the machine was 0.11 ha/h at a forward speed of 1.2 km/h, with a 50% field efficiency. The transplanter can transplant per row 33 seedlings/min, compared to 3.7 seedlings/min by manual method. Also, the saving in cost and labour is about 55 and 93.9% as compared to manual method. This transplanter offers efficient transplanting of potted seedlings, ensuring timely operation, labour savings and reduced drudgery compared to conventional practices.

来源平台：AGRICULTURAL RESEARCH