Production of G...

By Beatrice Awuor

Introduction

The Kenya Sugar industry has been working towards increasing sugarcane production to fulfill the sugar consumption demands for its ever-increasing population. According to Cane Availability Survey Reports 2021/2022-2022/2023 and 2023/2024, the area under sugarcane has been consistently increasing. Sugar cane production has now spread to 15 counties in the country. However, since land is a limited resource, we can only expand to a limited point. As a country, it’s time to reorient our attention to maximizing our yields per unit land. Presently, the average sugarcane yield in Kenya is around 60.52 tonnes per hectare, far below its capacity of between 90-150 tonnes per hectare.

One of the basic aspects of increasing sugarcane yields is providing good-quality seed cane to farmers. Good quality seed cane is the main prerequisite for improving the productivity of the sugarcane crop. Since sugarcane is propagated vegetatively, it favours the accumulation of pathogens. This is because the disease-causing pathogens are introduced into the new areas along with seed canes. The slow accumulation of different pathogens over time makes minor diseases become major ones. Disease-infected seed cane can play a significant role in the multiplication and spread of diseases, as has been the case with red rot, smut, wilt, grassy shoot, ratoon stunting, yellow leaf and leaf scald. Unfortunately, we have operated the industry without following the scientific system of seed cane production.

Seed Cane Production (The Three-Tier System)

The three-tier system is the scientific system of seed cane production involving a hierarchical approach, i.e., breeder seed (stage 1), foundation seed (stage 2) and certified seed production (stage 3). It is highly valued because it ensures a consistent supply of high-quality, disease-free seed cane, which is crucial for maximizing sugarcane yield and maintaining varietal purity. 

1. The breeder seed (progeny of nucleus seed)

This is the initial and most crucial stage where seed is produced on research farms under the direct supervision of scientists and breeders or a research institution. The breeder seed plots are carefully monitored for genetic purity and other quality parameters to ensure they meet the standards for the next generation. It involves using heat-treated setts (cuttings) and rigorous quality control to ensure the highest standards. Breeder seed is maintained at a very high standard of freedom from diseases and pests and genetic purity, typically 99.9%, to ensure that subsequent generations of seed also meet the required standards.  

1. The foundation seed

This stage is a secondary level of multiplication where breeder seed, which is the highest quality seed, is used to produce a large quantity of the foundation seed. It’s also produced under strict supervision at research stations or by selected, progressive farmers. The multiplication process is closely monitored to maintain the genetic purity and health of the seed. Rows or plants exhibiting poor vigor, off-type characteristics, or disease symptoms are promptly removed to maintain the quality of the foundation seed. The foundation seed stage acts as a crucial link between the high-quality breeder's seed and the commercial/certified seed production. Once the foundation seed is produced, it should be distributed to registered seed producers. The foundation seed stage ensures that high-quality seed is available for commercial production, ultimately contributing to improved sugarcane yields and quality. It also helps in scaling up the adoption of improved varieties among farmers.

1. Certified seed production

This is the final stage where the foundation seed is used to produce seed for commercial planting. The seeds are grown on identified farmer fields with continued monitoring for quality and distributed by sugar mills. This is the final stage before distribution to farmers for general cultivation. Certified seed production ensures that a large quantity of high-quality seed cane is available for planting. The process is regularly monitored by qualified personnel to ensure varietal purity and freedom from diseases and pests. If diseases or pests are detected, appropriate control measures are implemented.

Seed Cane Preparation

Once the certified or commercial seed cane reaches the appropriate maturity (usually 8-10 months), it is harvested. The healthy, mature canes are cut carefully into setts of 30-45 cm in length while protecting the buds. Each set should have 2-3 healthy buds. Lower internodes should have at least 60% moisture content, while other internodes should have at least 66%. No aerial roots and splits should be present in the seed cane setts.  Harvesting the seed crop one day before planting can improve germination.

Methods of treating seed cane setts

1. Chemical treatment

The seed canes are chemically treated to prevent fungal infections and pest infestations. Antifungal solution is usually prepared by mixing a suitable fungicide, such as a 0.5% solution of carbendazim or a mixture of areton and agallol or bavistin powder, with water at a concentration of 1 gram per liter. The setts are then submerged in the prepared solution for the recommended time. It’s important to make sure the cut ends and all surfaces of the setts are thoroughly coated with the solution and that the setts are allowed to dry slightly before planting. Alternatively, the setts can be treated with KMnO4, MgSO4, potassium Ferrocyanide, or Ammonium Sulphate.

1. Hot water treatment  

Hot water treatment is usually done to eliminate or reduce the incidence of diseases like RSD & smut. Water is heated to 50°C or 52°C. The setts are treated with the hot air at 50°C for about 2 to 2 half hours. It is important to ensure uniform heating of the water and consistent temperature throughout the treatment. Temperatures above 55°C can negatively impact germination and yield. After treatment, the setts are cooled immediately. The main benefits of hot water treatment are improved germination rates, increased cane yield, and reduced disease incidence. However, it should be noted that hot water treatment sometimes damages the buds, and this can affect germination.

Advantages of Planting Good-Quality Seed Cane

Healthy, high-quality seed-cane is crucial for successful and profitable farming because they are more likely to produce more tonnage of sugarcane with higher sucrose content, directly translating to increased sugar production. Good quality seed-cane ensures that the new crop is less susceptible to common sugarcane diseases like Ratoon Stunting Disease (RSD), smut and red rot. This reduces the need for costly disease management practices, risk of pest and disease outbreaks, and prevents yield losses. This translates to fewer pesticide and fertilizer applications, reducing input costs for farmers. Quality seed-cane ensures better germination rates and rapid growth, leading to a strong and healthy crop stand with higher sucrose content and yields. It also results in uniform stands, minimizing the need for gap filling and weed control after planting.

How to Ensure Adequate Production & Supply of Good Healthy Seed Cane to Farmers

A great number of sugarcane farmers are experiencing a lack of good-quality seed cane in the country. Kenya has faced a significant seed cane shortage, which has in turn led to the overall cane shortage and low yields.  As much as the Sugar Research Institute (KESRETI) and the millers are expected to carry out seed cane multiplication, distribution and certification, the quantities of seed cane produced by the two institutions have been inadequate, leading to the use of poor-quality seed cane such as ratoon crops and cane tops.  This has significantly contributed to lower sugarcane yields, poor crop quality, and reduced profitability for farmers. Here are some of the approaches that we can consider to reduce seed cane challenges in the country:

1. Increasing funding and investment on seed cane production

Inadequate funding of the Sugar Research Institute in the recent past and low investment by millers on seed cane production have greatly contributed to the shortage of quality seed cane. With the re-establishment of the research institute and the return of the Sugar Development Levy, KESRETI should embark on serious production of quality seed cane. This will also encourage the adoption of the improved varieties. Kenya Sugar Board should also establish a mechanism that ensures millers take responsibility for developing and supplying seed cane to their farmers. The board can work towards relating the amount of seed cane development by millers to their mill capacity.

1. Developing a one-stop portal or database for farmers

The industry, through KSB, can work towards developing a one-stop portal or database that has details of all farmers, hectares with sugar plantation, and possible harvest dates for better decision making, especially about the demand for seed cane. This will allow the industry to plan to meet the seed cane demand.

1. Recruiting certified seed cane producers

Due to the seed cane crisis in the country, the industry players should come up with a program where farmers from various catchment areas are specifically registered to produce certified seed cane. These farmers will be registered based on the potential of their fields after inspection. They should be provided with healthy foundation seed cane for multiplication. The farms should be closely monitored by crop inspectors or extension officers, or researchers to ensure that the certified seed cane produced is of the highest standard.  

1. Subsidizing the cost of seed cane

Good quality seed cane is usually very expensive for the small-scale farmers. The industry players should come up with a suitable way to reduce the cost of acquiring healthy seed cane. The price should be sufficiently attractive to farmers.

1. Sensitization of farmers

Sensitization of farmers is an integral part of encouraging the adoption of certified seed cane in the industry. Farmers need to know the methods of producing certified seed cane, how to identify quality seed cane and the advantages of planting high-quality, disease-free planting material. This includes increased yields, improved crop quality, and enhanced resistance to pests and diseases. Establishing demonstration plots where farmers can witness the superior performance of sugarcane from certified seeds in terms of yield, growth, and disease resistance can also promote adoption.

1. Enhancing regulation on the use of certified seed cane

Kenya Sugar Industry should have regulations that instruct registered sugarcane farmers to only plant either certified or approved seed cane. This is a long-term plan since farmers should be given time to allow them to remove all unapproved varieties from their farms. For this regulation to work, the industry should also work towards establishing efficient seed cane systems by ensuring that approved seed cane is available in each locality to be accessed by farmers on a timely basis.

Conclusion

The success of the Kenya sugar industry is highly dependent on sugarcane yield per unit of land. Good-quality seed cane is the basis for increasing the yield. It’s time for all the industry players to reorient their approach to ensure the availability of high-quality seed cane in all the catchment areas. When farmers use good-quality seed cane, employ a good crop management system and harvest their cane at the appropriate age, their yields will increase. This will earn them more returns while at the same time increasing the quality and quantity of cane supply to the mills, hence more sugar production.