A scientific study on evaluating the cost-effectiveness of Paddy seedlings using mechanized transplanters climatically vulnerable hotspot areas in Sri Lanka

Authors:
Eng. R.M.B Rajakaruna – Project Director, CSIAP
Mr. Frank Jeyasinghe – Climate Smart Agriculture Specialist (PMU), CSIAP
Ms. Sharmila Shanmuganathan – Gender Development Officer (PMU), CSIAP 

1.     Introduction

In most parts of Asia, paddy is transplanted by hand into puddled soil, which is labour-intensive and requires large volumes of water. Puddling helps to control weeds and retain water in the rice fields. However, it results in aggregate breakdown and destruction of macropores (Voase-Ringrose et al., 2000), besides being costly and time-consuming (Chauhan et al., 2012).

 Labor shortages across Asia are making manual transplanting untenable in paddy farming. Manual transplanting rarely provides uniform row spacing or optimal rice plant populations (Behera et al., 2009). Shortages of labor increase the risk of delayed transplanting which causes paddy yield loss.

Mechanical transplanting of paddy is the process of transplanting seedlings raised in a dappok nursery using a self-propelled transplanter. Using mechanized rice transplanting reduces the cost of crop establishment, saves labor, ensures timely transplanting, and attains optimum plant density that contributes to high productivity (Manjunatha et al., 2009).

However, farmers are familiar with direct seedling and parachute seeding methods in paddy land. The above-mentioned factors have stimulated interest in mechanical transplanting. Therefore, CSIAP is trying to assess the effectiveness of the three types of plenty seedlings in the climatically vulnerable hotspot areas in Sri Lanka. Those methods are (a) direct seedling, (b) parachute seedling, and (c) using the transplanter for paddy seedlings. 

2.    The process to use the paddy transplanter

Paddy seedlings are first grown in a dedicated nursery area, usually in a tray or raised beds, where they are nurtured until they reach the desired stage for transplantation. Then, the paddy field is prepared by ploughing and, levelling with water. This creates a suitable environment for the transplanting process. After that, the mechanized transplanter is brought to the field, and its settings are adjusted according to the desired planting density, spacing, and depth. The machine is typically operated by a motor. Then, the paddy seedlings are loaded into the transplanter's seedling tray from where they are automatically fed into the planting mechanism. As the transplanter moves forward, it plants seedlings on the rows in the field using specialized planting devices. The seedlings are then placed in rows at the desired spacing and depth. After the seedlings are transplanted, the field may be filled to the desired water level, depending on the cultivation method and growth stage of the crop.

3.     Research Problem
The research problem is smallholder farmers have a negative perception of the power-operated transplanters which are reducing the yield if they used the transplanter, the reason they say that space between two rows is higher (12”) and is not recommended according to the Department of Agriculture. So, CSIAP wanted to practically prove by doing the demonstration plots whether paddy yield is increased or not by using the transplanter. So, CSIAP scientifically tested three different paddy seedling methods which are direct seedling methods, parachute methods, and transplanter methods as the demonstration in the farmers' demonstration plot to prove and change their attitude towards the transplanter.

 The main reason is even though the row transplanting of paddy seedlings using power-operated transplanters is cost-effective and helps to increase the paddy yield, it is not familiar to the smallholder farming community in the climatically vulnerable hotspot area and has a negative perception of the reduction of yield in their paddy land. Therefore, the World Bank-financed Climate Smart Irrigated Agriculture Project (CSIAP) is trying to familiarize the transplanting of paddy seedlings using power-operated transplanters to smallholder farmers by doing the demonstration plot in smallholder farmer’s paddy land in 44 Agrarian Service Centers divisions and prove the effectiveness scientifically. 

4.    Research Objective
The objectives of this research are to evaluate the cost-effectiveness of the paddy transplanter used at the demonstration plots of the farmer’s paddy land in climatically vulnerable hotspot areas in 44 ASC divisions in Sri Lanka. The evaluation considered a comparison of different types of paddy planting methods and the performance of the mechanical transplanter in the small-scale paddy lands in climatically vulnerable hotspot areas in Sri Lanka.

Further, CSIAP tried to familiarize the row transplanting of paddy seedlings using power-operated transplanters as one of the main CSA technologies in paddy cultivation to the smallholder farmers and help to direct beneficiaries to control weeds using power-operated weeders and minimize agrochemical usage and reduce the cost of production on paddy farming.

 5.    Research Methodology and Study Area
CSIAP has taken steps to provide power-operated mechanized transplanters (with 06 rows planting base) to the 44 ASC divisions, covering whole project implementation areas except Southern Province. Each ASC has dispatched 04 numbers of transplanters with power weeders and nursery trays. As a strategy to popularize these transplanters among the beneficiaries, the project carried out a paddy transplanting demonstration program during the Maha season 2022/23 with selected beneficiaries in the project area by using mechanized transplanters.  

 The main scope of this program is to introduce farm mechanization as a strategy of CSA practice and technology and convince its benefits for smallholder farmers Meantime, CSIAP implemented the demonstration program in 44 ASCs covering various Agro-climatic regions in climatically vulnerable hotspot areas in 11 districts and 06 provinces.

 In addition, demonstration programs were carried out on 66 acres of paddy lands in 141 nos demonstrations with the participation of 132 smallholder farmers who live in the project area. Also, at the end of the cultivation program project carry out crop cutting survey in every demonstration plot and assess the effectiveness and impacts of using paddy transplanters compared with the yield of control plots, which are planted by following direct seeding and parachute planting methods. 

 Activities involved during the demonstration intervention
1.     Establishment of 03 paddy planting plots (1/2 ac at each) in each ASC (01-transplanting plot, 01 parachute cultivation plot, and 01 direct seeding plot)        
2.     Carry out capacity-building programs for the beneficiaries with the intervention of DoA
3.     Provision of seed paddy for all plots on free of charge basis
4.     Provision of chemical fertilizer for all plots on free of charge basis
5.     Provide 8225 numbers of parachute trays for relevant beneficiaries on free of charge basis (175 Nos trays per farmer)
6.     Carried out crops cutting survey to cover all plots (132 numbers demonstration plots)

5.1.         Province-wise transplanting demonstration plots extent during the Maha Season Cultivation in 2022/23

   5.2.        Materials used for the transplanting demonstration plots during the Maha Season Cultivation in 2022/23

6.    The finding of the Study
  6.1.        Key findings of the study
The paddy transplanter demonstration program was carried out during the Maha season cultivation program in 2022/23 in 44 ASC divisions in climatically vulnerable hotspot areas of 11 districts and 06 provinces in Sri Lanka.

·       The yield increase of the mechanized transplanting method is ranging from 19 - 46% (Average increase – 29.08%) when compared to the direct seeding method.

·       The seed paddy requirement for Mechanized transplanting is 63% less compared to the direct seeding method. It leads to saving Rs. 4680/- per acre.

·       When the use of Mechanized weeders for weed control, helps to curtail weed control costs by 60% and it leads to enhancing the growth of paddy plants through vigorous tillering as a matter of improving soil physical properties.

         6.1.1.   The results are presented for the three and half month (3 ½) paddy varieties after the crop cutting survey below the attached table:

    6.1.2.   The results are presented for the four and half month (4 ½) paddy varieties after the crop cutting survey below the attached table:

 6.2.       Benefits of the power-operated mechanized transplanters

•  The positive aspects of transplanting paddy seedlings using mechanized transplanters are numerous.

·       Mechanized transplanting allows for faster and more efficient planting of paddy seedlings, covering larger areas in less time compared to manual labor. This leads to decrease plant establishment costs.

·       Manual transplanting of paddy seedlings is labor-intensive and can be physically demanding. By using mechanized transplanters, farmers can reduce their dependency on manual labor, save on labor costs, and alleviate labor shortages during peak transplanting seasons.

·       Mechanized transplanters offer precise control over planting depth, spacing, and seedling placement. This results in better crop establishment, uniform growth, and optimal plant density, leading to higher yields as a result of increased tillering of plants.

·       Mechanized transplanting allows farmers to transplant seedlings within a shorter timeframe, as they are not constrained by the availability of manual labor. This can help them align their planting schedules with optimal weather and field conditions with maximum utilization of rainwater.

·       Mechanized transplanting ensures consistent spacing between seedlings, promoting uniform growth and minimizing competition for resources such as water, nutrients, and sunlight. This facilitates better nutrient uptake, reduces weed growth, and improves overall crop health.

·       Embracing mechanized transplanting represents a shift towards adopting climate-smart agriculture practices and technologies in Sri Lanka. It encourages the use of advanced technology, improves efficiency, and supports sustainable agricultural development, despite the labor shortage as one major prevailing issue in agriculture.

 7.    Weaknesses of the Transplanters
While there are several positive aspects of transplanting paddy seedlings using mechanized transplanters, it's important to consider the potential challenges or negative aspects associated with this approach.

·       Mechanized transplanters can be expensive to purchase or lease, especially for small-scale farmers who may have limited financial resources. The initial investment cost could pose a barrier to adoption for some farmers.

·       Access to mechanized transplanters may be limited in certain areas or among smallholder farmers. Lack of availability or limited access to these machines could prevent widespread adoption, particularly in remote or economically disadvantaged areas.

·       Operating a mechanized transplanter requires technical expertise and training. Farmers may need to invest time and resources in training operators or hiring skilled individuals, which could be challenging for those with limited access to training programs or qualified personnel.

·       As mechanized transplanting reduces the need for manual labor, there is a possibility of job displacement for agricultural workers who were previously involved in manual transplanting. This could have social and economic implications, particularly in regions where agriculture is a significant source of employment.

 8.    Remedies to overcome the issues

·       To overcome the above said weaknesses, CSIAP provided the transplanter to the 47 ASC divisions in climatically vulnerable hotspot areas in Sri Lanka

·       Smallholder farmers can get the services of the paddy transplanter for a reasonable rate from their ASC divisions.

·       CSIAP is conducting the CSA practices and technology training programs in the Eco-friendly Climate Smart Farmer Training School, Thirapane. Therefore, farmers can get technical knowledge.

·       Row transplanting can be done by using this mechanized transplanter which helps to use the power weeded for weed control and curtail the weedicide cost by 60%.

·       When compared to direct seeding, seed paddy requirements for the seed paddy transplanter is very low. It needs 15kg per acre which is 37% compared to the direct seedling seeds requirement (40kg per acre).

 9.    Conclusion

·       Mechanizing the transplanting of paddy can decrease labor requirements and costs for crop establishment. Most importantly it helps to increase the yield and help to control the weeds in the paddy land.

·       The findings of the study are mechanized transplanting offers several advantages over traditional manual methods which are increased yield productivity and efficiency, labor savings, and cost reduction, and improved planting accuracy, uniform crop growth, adoption of climate-smart agriculture practices and technologies.

·       Transplanting of paddy seedlings according to the rows is the most important activity to control weeds without spending on agrochemicals, which leads to reduced production cost, and decrease chemical contamination.

·       Since the transplanter needs a low quantity of paddy seeds per acre. It leads to minimizing the dependency on seeds paddy for paddy cultivation.

·       As per the crop cutting results, it is explicit that mechanized transplanting gives good results for the 31/2 – 4 month paddy varieties.

·       Hence, this transplanter is very useful the higher age paddy cultivation farmer in climatically vulnerable hotspot areas. Also, this mechanized transplanter can be recommended to popularize among the smallholder farming community.  

Acknowledgement:
We would like to acknowledge and give our special thanks to staff in Provincial Deputy Project Director’s Offices, CSIAP for their continuous support when undertaking this research. This paper and the research behind it would not have been possible without the exceptional support of them.