THE EFFECT OF DIFFERENT SEED RATES ON THE GROWTH AND YIELD OF RICE (A CASE STUDY OF RICE FARMERS IN KATCHA LOCAL GOVERNMENT AREA, NIGER STATE)

CHAPTER ONE

INTRODUCTION

1.1 Background of the Study

Rice (Oryza sativa L.) has moved from a festive dish to an everyday staple in Nigeria as population and urbanisation have grown, and the cost of importing it has made raising local output a policy priority. Production happens under upland, rainfed lowland and irrigated conditions, and increasing yields on existing land depends partly on decisions that farmers make at sowing.

Two broad ways of establishing the crop compete for farmers' attention. Transplanting raises seedlings in a nursery and moves them to the field; direct seeding broadcasts, drills or dibbles seed straight into dry or wet soil. Direct seeding saves labour and time but demands tight control of the quantity of seed sown and of weeds. At Talata Mafara in the Sudan savanna, Mani et al. (2017) compared rice varieties and planting methods under irrigation and found that transplanting gave higher 1000-grain weight and grain yield than broadcasting and drilling, and that Faro 45 out-yielded Faro 44 and Faro 57.

Within direct seeding, the seed rate is the lever the farmer controls most easily. It sets plant population, tillers and panicles per unit area, the strength of competition among plants and the money spent on seed. A thin stand leaves gaps for weeds; a dense one wastes seed, crowds plants, increases lodging and disease risk and may reduce grains per panicle.

Studies show how the crop adjusts. Bueno and Carandang (2023) sowed dry direct-seeded rice in the Philippines at 20, 40, 60 and 120 kg/ha. The rates of 40, 60 and 120 kg/ha gave similar yields, all above that at 20 kg/ha. The highest rate gave more panicles but fewer filled grains per panicle, while the lowest gave more filled grains but fewer panicles, and compensation among yield components worked well at 40 and 60 kg/ha, which the authors judged more attractive to farmers because seed costs less. Donayre et al. (2023), working with wet direct-seeded rice, raised the seed rate from 60 to 120, 180 and 240 kg/ha and found that shoot biomass of the weed Cyperus rotundus fell by 10%, 20% and 41%, although rice yield did not differ among the rates.

Rieffel Neto et al. (2000) in Brazil crossed seed rates (75, 150 and 225 kg/ha, then 30, 90 and 150 kg/ha) with row spacings and varieties. Narrower rows raised grain yield regardless of genotype, and they concluded that with efficient weed control and adequate water management seed rate can be reduced. The best rate therefore depends on seed distribution, variety, water and weed control, and cost.

What these studies do not show is how Nigerian farmers decide. Seed availability and price, the method of sowing, tradition and the look of the stand all play a part, and none of this appears in an experiment. Katcha Local Government Area is in Niger State, where smallholders grow rice in lowland and fadama areas and where the National Cereals Research Institute operates a station at Badeggi. This study surveyed rice farmers in Katcha to document the seed rates they use and what they believe those rates do to growth and yield.

1.2 Statement of the Problem

Rice farmers in Katcha sow different quantities of seed per hectare, depending on what is available and affordable and on personal experience. Experiments indicate that seed rate affects tillering, panicle number and weed suppression, and that very low rates can lower yield while very high rates waste seed (Bueno & Carandang, 2023; Donayre et al., 2023). Those studies were done mostly outside Nigeria (Rieffel Neto et al., 2000), or elsewhere in the country under different conditions (Mani et al., 2017), and the literature consulted for this study did not reveal a survey of seed rate practice and perceived effects among rice farmers in Katcha.

Farmers may therefore be sowing too little, producing thin and weedy stands, or too much, wasting seed and overcrowding plants. Extension agents have no local figures on which to build advice on sowing. This study set out to provide them.

1.3 Objectives of the Study

1.3.1 General objective

To assess, by questionnaire, the effect of different seed rates on the growth and yield of rice among farmers in Katcha Local Government Area, Niger State.

1.3.2 Specific objectives

(a) to describe the socio-economic profile of the rice farmers

(b) to document the seed rates and methods of sowing the farmers use

(c) to establish how farmers judge stand establishment, tillering and plant growth at low, medium and high seed rates

(d) to establish how farmers judge the number of panicles and grain yield at those seed rates

(e) to identify the problems that farmers face with seed rates and the help they would like.

1.4 Research Questions

RQ1: What is the profile of rice farmers in Katcha?

RQ2: What seed rates and sowing methods do they use?

RQ3: How do they judge stand establishment, tillering and growth under different seed rates?

RQ4: How do they judge panicles and grain yield under different seed rates?

RQ5: What problems do they face and what help do they want?

1.5 Research Hypotheses

The following null hypotheses were tested at the 0.05 level of significance:

H01: The seed rate used by farmers is not significantly related to their establishment method.

H02: Perceived rice growth is not significantly affected by seed rate.

H03: Perceived rice yield is not significantly affected by seed rate.

1.6 Significance of the Study

To farmers, the study offers a picture of what neighbours sow and what they believe works, which may help them save seed and improve stands. To extension agents and rice development programmes in Niger State, it supplies local data on seed use for advice and planning. To researchers, it provides a baseline of farmer practice against which controlled trials on seed rate in the southern Guinea savanna can be designed and judged.

1.7 Scope and Limitations of the Study

1.7.1 Scope

The study covers rice farmers in Katcha Local Government Area and is limited to seed rate. It covers farmer profile, seed rates and sowing methods, perceived effects on growth and yield, and constraints.

1.7.2 Limitations

Responses rest on recall and judgement and may differ from measured values. Some farmers measure seed in tins or bowls, which are hard to convert into kilograms per hectare. Only a limited number of respondents could be reached, so results should be applied with care elsewhere.

1.8 Definition of Terms

Broadcasting: scattering seed over the soil surface without placing it in rows.

Direct seeding: establishing rice by sowing seed directly in the field instead of transplanting seedlings.

Growth: visible development of the rice plant (height, tillering and vigour) as perceived by farmers.

Seed rate: the quantity of seed sown per unit area, usually in kilograms per hectare.

Yield: the quantity of paddy rice harvested per unit area.

REFERENCES

Bueno, C. S., & Carandang, R. B. (2023). Yield component compensation as affected by seeding rates in dry direct-seeded rice. The Philippine Agricultural Scientist, 106(3). https://doi.org/10.62550/EN052023

Donayre, D. K. M., Jimenez, J. J. L., Pascua, H. G., & Martin, E. C. (2023). Influence of seeding rate and flooding period on growth of lowland ecotype Cyperus rotundus L. and yield of wet direct-seeded rice under dual culture. Philippine Journal of Science, 152(2), 665–668.

Mani, H., Muhammad, A., & Haruna, F. D. (2017). Response of rice varieties to various planting methods under irrigation at Talata Mafara in Sudan savanna. FUDMA Journal of Sciences, 1(1). https://fjs.fudutsinma.edu.ng/index.php/fjs/article/view/1221

Rieffel Neto, S. R., da Silva, P. R. F., Menezes, V. G., & Mariot, C. H. P. (2000). Response of lowland rice genotypes to plant arrangement. Pesquisa Agropecuária Brasileira, 35(12), 2383–2390. https://doi.org/10.1590/S1678-3921.pab2000.v35.6035