Influences of harvester and weather conditions on field loss and milling quality of rough rice

Ragab Khir,Zhongli Pan,Griffiths Atungulu,Ding Chao

doi:10.25165/j.ijabe.20171004.2993

Abstract

A better understanding of factors affecting field losses and milling quality during harvest is needed to improve the economic value of rice. The main objective of this study was to evaluate the impact of harvester header, harvester type, and weather conditions on field loss and milling quality of rough rice. Four popular harvesters equipped with different headers: John Deere 9870 with header D60-S, John Deere 9860 with header D972-S, Hardy, and John Deere 9770 with stripper header were evaluated in this study. The header and total field losses of rice were evaluated for each harvester under regular, rainy and windy weather conditions. Tests were conducted in a rice field cultivated with medium grain rice, variety M206, at Grimes, CA. Total rice yield (TRY), head rice yield (HRY) and whiteness index (WI) were examined to evaluate the effect of weather conditions on milling quality. The obtained results revealed that the rice field loss was affected by harvester header and type, and weather conditions. Among the conventional headers, D60-S significantly reduced the rice loss compared to the D972-S and the Hardy. Harvesting with John Deere 9860 resulted in significant header and field loss compared to other tested harvesters. The average loss increased from 236.2 kg/hm2 and 445.2 kg/hm2 under regular condition to 711.1 kg/hm2 and 907.9 kg/hm2 under windy condition for John Deere 9870 and John Deere 9860, respectively. The corresponding loss percentages increased from 2.6% and 4.9% to 7.9% and 10.1%. HRY was significantly affected by weather condition at harvest time. However, the weather condition had no significant effect on TRY and WI. To minimize the rice field loss and obtain good milling quality, commercial rice harvesting during regular weather conditions is important. A proper combination of harvester type and header could be vital for reducing the rice loss. Keywords: rice, harvesters, field loss, weather conditions, milling quality, harvester header DOI: 10.25165/j.ijabe.20171004.2993 Citation: Khir R, Atungulu G, Ding C, Pan Z L. Influences of harvester and weather conditions on field loss and milling quality of rough rice. Int J Agric & Biol Eng, 2017; 10(4): 216–223.

Highlights

Rice loss in the field during harvesting presents a direct economic loss to growers
The results indicated that the weather condition had no significant effect on Total rice yield (TRY) and whiteness index (WI)
The research showed that the rice field loss and milling quality were affected by harvester headers, harvester types and weather conditions

Summary

Introduction

Rice loss in the field during harvesting presents a direct economic loss to growers. In California, most rice growing areas encounter strong wind and rainfall events of various magnitudes during harvesting season, which cause rice lodging and moisture change and affect performance of harvesters, rice loss and milling quality[1,2]. In light of improved combine harvesters and emergence of new rice varieties, there is a need for continuous assessments of rice loss and milling quality[3]. Understanding the impact of weather conditions, harvester headers, and harvester types on rice loss in the field and milling quality is of a great importance for mitigating rice loss and milling quality. 2017 Khir R, et al Influences of harvester and weather conditions on field loss and milling quality of rough rice Vol 10 No. 217. The loss of grain in the field caused by harvesters is classified into header loss (losses at the front of a harvester) and combining losses (losses at threshing, separation and cleaning units) or gathering loss and processing loss[4]. Header losses are known to vary widely with the type, variety and condition of the crop, and the designing features of the header[1]

Objectives

Methods

Conclusion