Ratoon Management in Sugarcane

Ratoon is a crop which is allowed to grow in the same field from the eye buds left underground in the portion of stalk over stubbles after harvest of the main crop without planting seed setts a new. Ratoons are considered as a free gift by the Sugarcane growing farmers. Even though 40-50% of the Sugarcane area harvested is of ratoons. Farmers do not pay proper attentions in proper management of the ratoon crops and as a result yield of ratoon crop is very low. Basically, ratoon cropping implies:  more than one harvest from a single planting, regrowth from basal buds on the stem or crown which is situated at the surface of the ground and harvesting the aerial portion of the plant.

Basically, ratoon cropping implies:

1. more than one harvest from a single planting:
2. regrowth from basal buds on the stem or crown which is situated at the surface of the ground; and
3.  harvesting the aerial portion of the plant.

In simple terms ratooning is raising a fresh crop of sugarcane from the preceding plant crop stubble regrowth without fresh planting of setts. This is first ratoon. When a ratoon is raised from the stubble regrowth of the first ratoon, it is second ratoon and so on. The sugar factory cane staff many a time refer first ratoon as R-one, the second ratoon as R-two and so on. The first crop raised by planting setts is referred to as plant crop.

Advantages of ratoon crop:

Even though ratoons are poor in yield, they are essential for overall economy of Sugarcane cultivation. They offer several advantages which are given below: 

1. The cost of land preparation, cost of seed and sowing is saved (about 25-30%).
2. Ratoon crops are ready to harvest earlier than the main crop and helps in running sugar mills earlier.
3. The quality of produce is superior to planted canes.
4. The ratoon crop utilizes the residual fertility of the previous crop.
5. The yield remains equal to the planted crop if due care is taken.
6. Ratoons develop more extensive root system, make better use of moisture, produces more tillers and foliage in drought or water logging condition.
7. Ratoons often give better quality cane. Therefore, they may help improve sugar recovery at the start of the crushing season.

Disadvantages or ratoon crop:

1. It is liable to be attacked by many insect and disease.
2. Soil becomes poor in fertility when ratooning is done for more than 2 years.
3. Free or ‘gift crop’ attitude of the farmers towards ratoon and therefore poor ratoon crop management.
4. Reduced initial population because of reduced stubble sprouting.

The major causes for yield decline in ratoons are:

1. Free- or gift crop attitude of the farmers towards ratoons and therefore poor ratoon crop management.
2. Reduced initial population because of reduced stubble sprouting
3. Decline in the soil nutrient status.
4. Soil compaction and poor soil physical status.
5. More incidence of pests and diseases.
6. Adverse weather conditions at the time of plant crop harvest, mostly in the sub tropics.

The following operations should be considered for ratoon management for higher yield:

Pre harvest operations:

1. Selection of good ratooning varieties e.g. Co1148, CO 8121, B.O-88, B.O-91, B.O-99, CoS-767 and UP-1.
2. Parent crop from which ratoons are to be taken must have optimum plant population of about one lakh millable canes/ha and proper management of previous crop is a must.
3. The parent crop should be harvested earlier in October (autumn planted crop) and in February/March (spring planted crop) for keeping ratoon.
4. Proper management (high input, insect pest control etc.) should be done for the main crop.
5. Dismantled the ridges and made flat land before main crop harvesting.

Post-harvest operations:

1. Harvest the canes as close to the ground as possible to promote better sprouting.
2. After harvesting of main crop, dry leaves (trashes) of previous crop should be burned and irrigate to the stubbles. The burning trashes helps in destroying eggs, larvae of insects, disease pathogens and weeds. Burning evolves heat, which converts sucrose of stubbles into glucose for quick sprouting of ratioons. 
3. Planting new cane setts should fill up gaps in the field.
4. Irrigation should be applied after 6-7 weeks of the crop harvesting. Rests of the irrigations are applied in the same pattern as for planted crop. 
5. Use stubble-shaving machine for maintaining proper height of stubbles.
6. Gap filling should be done with 3 budded setts after harvesting of main crop.
7. Fertilizer should be incorporated in inter row spaces about 25-30cm away from plant rows. The rate of application should be about 150-200: 60:40kg NPK/ha as first application after destroying the bunds and first irrigation.
8. The weed control, earthing-up, hoeing, and plant protection measures should be followed as main crop.
9. Drainage should be provided to drain out excess water.
10. Ratoon crop ordinarily gives lower yield than the plant crop but if crop is managed properly a cane yield of 60-100 tonnes/ha can be easily taken.

Note:

All the important practices, which are practiced for main crop, should be followed for ratoon management practices.  Farmers should remember the following points for the management of ratoon crop: Varieties, plant population and gap filling, method and optimum time of harvesting of previous crop, trash disposal and burning, stubble shaving, manure and fertilizer application, water management etc. Other cultural practices are: earthing up, wrapping, propping, detrashing, control of water shoot, control of flowering etc. They are similar with main crop management practices.