Self Propelled Spoke Wheel Nitrogen Applicator for Rice Residue Mulched Wheat Crop

Abstract

In order to reduce nitrogen losses sustained in broadcasting of urea under high rice straw mulched wheat crop and to enhance crop yield, a self propelled spoke wheel nitrogen applicator for injecting nitrogen in liquid form beneath the soil surface was designed, developed and evaluated under actual field conditions. The machine comprised four sets of spoke wheel having radial injectors attached to a distribution hub with inline mounted flow control valve and cut-off system. Constant supply of liquid urea to the distribution hub by means of a piston pump produced pressure adequate to expel urea solution through the flow control valve as it opened. The opening and closing of flow control valve was regulated through a specially designed lever and stationery cam. The average field capacity and efficiency of the machine were found to be 0.36 ha·h-1 and 88.9%, respectively. Yield and nitrogen use efficiency (NUE) of wheat crop fertilized with spoke wheel nitrogen applicator was 20 and 47 % respectively higher than that of broadcasting method of nitrogen application. Lower nitrogen accumulation in mulch and higher nitrogen uptake in wheat crop indicated reduced nitrogen losses in case of point injected nitrogen application over broadcasting. Hence, spoke wheel nitrogen applicator acquires a promising option not only for enhancing crop yield but also environment protection.

Sa ciljem smanjenja gubitaka azota pri ubacivanju uree pod usitnjene žetvene ostatke radi povećanja prinosa, konstruisan je samohodni aplikator za ubrizgavanje tečnog azota pod površinu zemljišta. Mašina se sastoji od četiri kompleta točkova sa paocima i injektorima postavljenim na haubu sa ugrađenim ventilom za kontrolu protoka i isključenje sistema. Konstantan dotok tečne uree do distributera preko klipne pumpe obezbeđen je odgovarajućim pritiskom za izbacivanje rastvora uree kad je kontrolni ventil otvoren. Otvaranje i zatvaranje kontrolnog ventila je regulisano specijalno konstruisanom ručicom. Srednji poljski kapacitet i efikasnost mašine su iznosili 0.36 ha·h-1 i 88.9%, redom. Prinos i efikasnost iskorišćenja azota (NUE) kod pšenice đubrene ovim aplikatorom azota bili su 20 i 47%, redom, viši nego pri uobičajenom rasturanju azota. Niža akumulacija azota u malču i više usvajanje azota kod pšenice ukazuju na manje gubitke azota kod tačkastog ubrizgavanja azota u odnosu na rasturanje. Tako ovaj aplikator azota predstavlja povoljniju opciju, ne samo za povećanje prinosa nego i za zaštitu okoline.