Authors:

Abstract

This study investigated the effect of reel index and type of combine harvester on header losses when harvesting the long grain paddy variety Bg 94-1. The field experiment was carried out in a split plot design with three replicates. Two brands of popular combine harvesters (Kubota® DC-68G and Agroworld® 4L-88) and three levels of reel index i.e. 1.2, 1.7 and 2.5, were assigned to the main plots and sub plots, respectively. The results revealed a greater header advancement and an increased tine bar velocity at the reel index of 1.2 resulting in a higher header losses in both combine harvesters. Similarly, lesser header advancement and increased number of impacts of the reel on panicles at the reel index of 2.5 also caused greater header losses. The reel index of 1.7 resulted in significantly low header losses of 38.8 and 45.8 kg/ha from Kubota and Agroworld® harvesters, respectively. The performance evaluation revealed that Kubota combine harvester had relatively higher field capacities and field efficiencies at all three reel indices when compared to Agroworld®machine. The field capacities decreased from 0.380 to 0.245 ha/h for Kubota and from 0.197 to 0.175 ha/h for Agroworld® combine harvesters across the reel indices 1.2 to 2.5. The field efficiencies increased from 49.3 to 60.9% and 30.6 to 50.8% across the reel indices 1.2 to 2.5 for Kubota and Agroworld® harvesters, respectively. In general, a reel index of 1.7 would be the ideal for minimum header losses as well as an acceptable field capacity and field efficiency for both types of combine harvesters.

Tropical Agricultural Research Vol. 25 (1): 1-13 (2013)

Keywords: Combine harvester, Field capacity, Field efficiency, Header loss, Reel index