Modification and comparison of tomato pneumatic planter with mechanical planter

In 1996, in order to plant tomato seeds directly into soil, a tomato pneumatic planter has been designed and constructed at Gorgan Agricultural Research Center. Then, the constructed pneumatic planter was tested and evaluate at Fars Agricultural Research Center in 1997. Results of this evaluation indicated that the tomato pneumatic planter had some problems and low efficiency so that values of seed emergence percent, planter accuracy in planting one seed, two seeds and three seeds, planter accuracy in providing suitable space between seeds on planting rows were 50.75%, 47.1%, 45.3%, 6%, and 32.2%. But, with solving some problems of the tomato pneumatic planter, the planter efficiency increased considerably. In order to solve these problems firstly, to prevent air removing from the air systems of planter and decrease air pressure drop, the air system completely was sealed. Secondly, to increase the planter accuracy in metering tomato seeds, the driving system of planter was improved so that with changing drive and driven years, angular velocity (rotation number per minute) of seed drum reduced. Also, to provide 15cm distance between hills on planting rows, number hole rows on seed drum was increased from 8 to 16 hole rows. In addition to, mentioned improvements to increase seeds emergence percent, coverers of the pneumatic planter were improved so that the coverers could cover completely on planted tomato seeds. Planting practices of tomato were carried out by the improved pneumatic planter and conventional tomato planter in experimental farm at Hashtgerd, Karaj. These planters were tested and evaluated and then compared with each other at 5% level by t-test. The obtained results from evaluation of the improved tomato pneumatic planter on farm indicated that values of seed emergence percent, accuracy in planting one seed, two seeds and three seeds and planter accuracy in providing desirable space between seeds on planting rows were 92.5%, 91.5%, 92%, 93.5%, and 93%. Meanwhile, except of seed emergence percent, other above factors was not possible to measure for the tomato mechanical planter because, the tomato mechanical planter plants continuously tomato seeds the same as grain drill. The value of seed emergence precent for the mechanical planter indicated significant differences between values of seeds emergence for the mechanical planter was 94.6%. However, statistical analysis didn&rsquot indicate significant difference between values of seeds emergence for the mechanical and pneumatic planters. After improving the tomato pneumatic planter, values of seeds emergence percent, planter accuracy in planting one seeds, two seeds and three seeds and planter accuracy in providing suitable space between seeds on planting rows were improved and increased about 41.7%, 44.4%, 46.7%, 87.5% and 60.8% respectively. Values of seeds breakage percent for the improved pneumatic planter and the mechanical planter were determined 1% and 8% respectively. The results of field test indicated that seed number per each meter from length of planting rows for the improved pneumatic planter and the tomato mechanical planter in case of hilling ( planting three seeds) were 21.3 and 116.4 seeds per meter respectively. With a simple calculation and by considering grain thousand weight of tomato seed it was determined that in case of hilling seed rate per hectare for the improved pneumatic planter and the mechanical planter are about 835g/ha and 4500 g/ha respectively. Also, with considering price of one kilogram tomato seed that is about 600,000 Rls, it is determined that if for planting tomato seeds instead of the mechanical planter from the improved pneumatic planter be used the consumed seed cost would be reduced about 2200,000 Rls per hectare. The obtained results of the study showed that application the tomato improved pneumatic planter can be a suitable replace for the tomato mechanical planter to plant tomato seeds. Since, the pneumatic planter in comparison to the tomato mechanical planter can decrease seed rate per hectare and it eliminates thinning operations. As a result, by using the tomato pneumatic planter, cost of planting and crop protection operations would be reduced.