Template:Chapter 1.4
1.4 -Sowing seeds in rows (line sowing)
Kirsten Radcliffe, University of Guelph, Canada
Suggested citation for this chapter.
Radcliffe,K. (2022) Sowing seeds in rows (line sowing). In Farmpedia, The Encyclopedia for Small Scale Farmers. Editor, M.N. Raizada, University of Guelph, Canada. http://www.farmpedia.org
Introduction
Introduction: Traditionally, subsistence farmers have utilized a method known as broadcasting to sow seeds. Generally, broadcasting involves manually dispersing seeds throughout the field by throwing handfuls over the soil. In order for farmers to obtain a substantial yield with broadcasting, seeds must be sown at a relatively high density. Since the seeds were dispersed on the soil surface, some seeds could be lost to birds or field run-off during rainstorms (Johansen, Haque, Bell, Thierfelder, & Esdaile, 2012). Alternatively, line sowing involves sowing seeds in uniform rows either manually or with machinery (Food and Agriculture Organization, 2007). This sowing method allows for higher yields due to reduced plant competition for sunlight, water, and nutrients. Additionally, sowing seeds in rows allows for enhanced weed and pest management since farmers can more easily move through the field to removed weeds and monitor crops for pests or disease (Barberi, 2002).
Benefits of Line Seeding
Sunlight, water, and nutrients are all essential components to the development and growth of plants. Plants absorb sunlight using the photo pigments in their leaves, which is then converted into energy for growth (Maddonni & Martinez-Bercovich, 2014). Depending on the plant species the efficiency of this conversion process differs slightly (Tesfaye, Walker, & Tsubo, 2006). When plants become too crowded, competition for access to sunlight, nutrients, and water ensues.
Unfortunately, many farmers sow their crop seeds at a higher density than what is recommended by their local extension services resulting in increased levels of plant stress and the subsequent reduction in crop yields (Wiyo, Kasomekera, & Feyen, 1999). Access to sunlight plays a major role in determining crop yield as it is essential to plant growth. A study conducted by Maddonni and Martinez-Bercovich found that maize grain yield is primarily determined by kernel number per unit land, which is positively correlated with the amount of photo synthetically active radiation intercepted by the leaves (2014). Plants, which emerge earlier, will have competitive advantage in this situation, surpassing the others in growth and eventually blocking the surrounding plants access to sunlight (Maddonni & Martinez-Bercovich, 2014). The larger the size of the leaf and the shorter the period required for leaf development will allow for greater radiation interception. Singels and Smit conducted research on sugarcane and row spacing, finding that leaf development is affected by row spacing (2009). The higher rates of leaf development occurred in the wider rows, indicating that plants require adequate space to access sunlight and nutrients required for growth (Singels & Smit, 2009). Similarly, plants, which are able to develop their root systems earlier, will have greater success in obtaining the scarce water and nutrients vital for growth (Barberi, 2002). The practice of sowing seeds in lines allows for optimum sunlight exposure, and soil water utilization. Maddonni and Martinez-Bercovich discovered that grain yield reductions were most prevalent in fields where crops were planted in higher densities (2014). In addition, broadcasting tends to require a higher seed input to compensate for losses, making line sowing a more beneficial choice when seed prices are high.
Sowing in rows enables farmers to monitor their crops for signs of pests or pathogens and have greater access to weeds. This aspect is extremely important as an unnoticed or untreated pest or pathogen could wipe out yields leaving the farmer with no income or food for that season. Common bean (Phaseolus vulgaris L.), cowpea (Vignaungviculata L.), chickpea (Cicer arietinum L.), and pigeon pea (Cajanus cajan L.) are major grain legumes grown in semi-arid regions (Tesfaye et al., 2006). These legumes are a primary source of dietary protein and income for subsistence farmers. The dry matter production and subsequent yield has been found to be highly associated with the fraction of PAR intercepted by the plant (Tesfaye et al., 2006). Studies conducted by Barberi using pigeon pea (Cajanus cajan L.) found that an inter-row distance of 40-50 centimetres allowed for optimal grain yields per unit and hoeing between rows (2001).
How to Practice
A simple method that can be employed to sow seeds in rows involves the use of string and wood stakes. Depending on the region and species being planted row spacing will vary. Measuring the dimensions of the field is recommended to ensure uniform spacing between rows (Food and Agriculture Organization, 2007). To ensure the rows are straight, tie the string to two wood stakes and place the stakes at either end of the field making sure that the string is tight. The string acts to mark where the rows will be planted, acting as a visual guide for the sowing process. The seeds can either be dribbled into the furrows and covered over or put into a hole, which is created using a hoe (Food and Agriculture Organization, 2007). The method involving the use of a hoe to dig holes is typically used for larger crops, which require greater spacing between crops (Food and Agriculture Organization, 2007). Mechanized tools are also available to farmers at a relatively low cost. Jab planters enable the farmer to plant seeds into untilled soil, eliminating the labours tasks of digging holes and bending down to plant the seeds (Johansen et al., 2012). However, using this tool can bring challenges such as the tip becoming clogged with soil, taking away from its intended efficiency (Johansen et al., 2012). In order for line sowing to be most beneficial it must be employed with a corresponding weed suppression strategy such as a cover crop or herbicide treatment.
Picture Based Lesson to Train Farmers
For the South Asian version (pictures only, text for you to insert), click this link for lesson 2.4:http://www.sakbooks.com/uploads/8/1/5/7/81574912/2.4.pdf
For the East/South Asian version (pictures only, text for you to insert), click this link for lesson 2.4:http://www.sakbooks.com/uploads/8/1/5/7/81574912/2.4e.s.a.pdf
For the Sub-Saharan Africa/Caribbean version (pictures only, text for you to insert), click this link for lesson 2.4:http://www.sakbooks.com/uploads/8/1/5/7/81574912/2.4subsaharan_africa_carribean.pdf
For the Latin-America version (pictures only, text for you to insert), click this link for lesson 2.4:http://www.sakbooks.com/uploads/8/1/5/7/81574912/2.4latin_america.pdf
For North Africa And Middle East version (pictures only, text for you to insert), click this link for lesson 2.4:http://www.sakbooks.com/uploads/8/1/5/7/81574912/2.4n._africa_middleeast.pdf
Source: MN Raizada and LJ Smith (2016) A Picture Book of Best Practices for Subsistence Farmers. eBook, University of Guelph Sustainable Agriculture Kit (SAK) Project, June 2016, Guelph, Canada.
Challenges
Although planting seeds in rows is beneficial for yield levels it is also considerably time consuming. If farmers use manual line sowing methods they will have to prepare the field for sowing with a hoe before they can distribute the seeds. Compared to broadcasting seeds, line sowing requires significantly more time and labour, which may deter farmers from adopting it into their practices. This especially true in the case of lower value crops. However, a farmer may be more inclined to adopt line-sowing practices for higher value cash crops. For instance, farmers will almost always adopt line-sowing practices in the case of many fruits and vegetables, which are high in labour, value, input, and susceptible to pests and disease. Whereas, low value cereals and legumes are more likely to be broadcasted since the perceived benefit of adopting line sowing is not as high as in fruits and vegetables. Broadcasting seeds at higher densities can also be beneficial in suppressing weed populations. If a farmer does not have the time or labour available to keep up with the weeding of their fields broadcasting may be a better option. The field being used by a farmer is not always located near their house, limiting access and time available for weeding making broadcasting more attractive. Line sowing permits spaces in-between the rows of crops in which weeds can grow, where as, broadcasting leaves little space for weeds to develop. Furthermore, broadcasting can be successful in muddy soils, whereas, line sowing, which may require machinery or a jab planter, tends to be problematic. Depending on the land, line sowing may require both the jab planter and plough to loosen the soil first, whereas, broadcasting may need no field preparation. When deciding between line sowing and broadcasting it is very important to consider the crops being grown. Some crops can be quite successful in mixed broadcasting, while other such as corn struggle due to shading.
References
1. Barberi, P. (2002). Weed management in organic agriculture: are we addressing the right issues? Weed Research, 42, 177–193. Retrieved from http://journals2.scholarsportal.info.subzero.lib.uoguelph.ca/pdf/00431737/v42i0003/177_wmioaawatri.xml
2. Food and Agriculture Organization. (2007). Labour saving technologies and practices: Row planting, hand seeders and planters.
3. Johansen, C., Haque, M. E., Bell, R. W., Thierfelder, C., & Esdaile, R. J. (2012). Conservation agriculture for small holder rainfed farming: Opportunities and constraints of new mechanized seeding systems. Field Crops Research. http://doi.org/10.1016/j.fcr.2011.11.026
4. Maddonni, G. A., & Martinez-Bercovich, J. (2014). Row Spacing, Landscape Position, and Maize Grain Yield. International Journal of Agronomy. Retrieved from http://go.galegroup.com.subzero.lib.uoguelph.ca/ps/retrieve.do?tabID=T002&resultListType=RESULT_LIST&searchResultsType=SingleTab&searchType=AdvancedSearchForm¤tPosition=55&docId=GALE%7CA417738017&docType=Article&sort=RELEVANCE&contentSegment=&prodId
5. Singels, A., & Smit, M. A. (2009). Sugarcane response to row spacing-induced competition for light. Field Crops Research, 113, 149–155. http://doi.org/10.1016/j.fcr.2009.04.015
6. Tesfaye, K., Walker, S., & Tsubo, M. (2006). Radiation interception and radiation use efficiency of three grain legumes under water deficit conditions in a semi-arid environment. Europ. J. Agronomy, 25, 60–70. http://doi.org/10.1016/j.eja.2006.04.014
7. Wiyo, K. A., Kasomekera, Z. M., & Feyen, J. (1999). Variability in ridge and furrow size and shape and maize population density on small subsistence farms in Malawi. Soil & Tillage Research, 51, 113–119. Retrieved from http://journals2.scholarsportal.info.subzero.lib.uoguelph.ca/pdf/01671987/v51i1-2/113_virafsossfim.xml