Quantitative and Qualitative Losses in Paddy, Maize and Greengram Stored under Household Conditions in Anuradhapura District of Sri Lanka

Substantial losses are common due to various reasons of durable crops during storage, which threatens economy, health and food security. Despite the frequent reports on post-harvest losses of paddy and other cereals throughout Sri Lanka, a comprehensive study has not been conducted in Anuradhapura district in recent past to assess storage losses of aforesaid commodities. Objectives of this study were to find out main types of durable crops stored following harvest, and their quantitative and qualitative losses incurred during storage period at the household level in Anuradhapura district of Sri Lanka. Data were collected throughout Anuradhapura district representing all 22 divisional secretariats. The main stored commodities were paddy, maize and greengram. The storage period varied from 4 to 12 months. The storage losses of Nadu and Samba rice varietal types respectively were highest in Palagala and Kekirawa, whereas losses were minimum in Rambewa and Galenbindunuwewa. The main qualitative losses were the presence of damaged seeds, grain flour/dust, grains without kernel and faecal matter. The study highlights that severe quantitative and qualitative losses occur during storage of rice, maize and greengram, and appropriate remedial measures are needed to be developed to minimize the said losses ensuring food security.


Introduction
As the production of cereals is seasonal, the excessive production needs to be stored to meet the demand during off-season (Proctor 1994;Dowell and Dowell 2017). Numerous types of quantitative and qualitative deterioration of a food crop occur from harvest/production until consumption. Those damage reduce the nutrient content, caloric value, edibility, and consumer acceptability of food (Kader 2002;Hagstrum and Subramanyam 2006). The various losses occurred during storage of food eventually cause low marketability and escalates the prices of food (Zorya et al. 2011). Estimates by the Food and Agriculture Organization of U.N. indicate the global loss of about 1.3 billion tonnes of food annually (Gustavson et al. 2011). In developing countries, the losses of stored food products can be high as 50% of total production (Wijayaratne et al. 2018). In Sri Lanka, approximately LKR 18-20 billion is lost annually due to post-harvest losses of rice and other durable crops (Wijayaratne 2020

Data Collection
The data were collected by a survey conducted

Statistical analyses
Data collected from each DS division with respective of amount of each crop harvested, amount stored, types of losses experienced, quantity of each loss during storage period were analysed to find the mean values of each parameter. Quantitative losses were analysed as percentage of storage loss with respective to the stored quantity and presented descriptively.

Stored Commodities
Storing of remaining portion of the crop yield following consumption and/or selling was found out be quite common. However, in the present study, mean percentage of unmilled rice stored in Anuradhapura district was found to be lower than that previous study.
Compared with unmilled rice, the number of DS divisions stored greengram or maize after harvesting was relatively lower. Furthermore, the percentage stored with respective to the production was also lower in both maize and greengram compared to unmilled rice. In maize, percentage stored varied from 3.3% (in Vilachchiya) to 33.6% (in Rambewa) (Fig. 3). For Greengram, storage was 7% in Rajanganaya and 52.5% in Rambewa (Fig. 4). which recorded 13.3% loss at storage (Fig. 7).
However, there were no significant differences between the losses in 4 DS divisions (data not

Qualitative Losses of Stored Commodities
Four types of qualitative losses were found in stored commodities. These were damaged seeds, grain flour, unfilled grains and presence of faecal matter. While the apparent cause for these conditions being the activities of insects, rodents and moulds, the future research should be designed to find the exact reason/s underlying.
The highest percentage of damaged rice seeds was recorded in Kekirawa and Palagala (85%) whereas the lowest percentage was recorded in Galenbindunuwewa (24%) (Fig. 8). The highest and lowest percentages of grain flour/dust in stored rice were recorded in Padaviya (86%) and Nuwaragampalatha East (35%), respectively (Fig. 9). The highest empty grains percentage was recorded in Vilachchiya (100%) whereas the lowest was recorded in Padaviya (19%) (Fig. 10). At least, 75% of rice stored in all the DS divisions were contaminated with faecal matter (Fig. 11).
Previous studies conducted in Sri Lanka have revealed that nearly 80% of the storage losses of grains are due to insect attack. These losses cause primarily loss of weight, nutrients and germinability, occurrence of bad smell and taste, changes of colour, clump of grains, and growth of fungus. These result in economic loss due to reduced market value (Wijayaratne and Rajapakse 2015).
In maize, the qualitative damage was substantial as the mean percentage loss is approximately 33%. The percentages of damaged seeds and grain flour/dust were either equal or higher than 67% extending to 100% loss in certain DS

Conclusions
The main durable crops stored following harvest

Conflicts of Interest:
The authors have no conflicts of interest regarding this publication.