Sugar beet a potential crop for sugar production
Sugar beet plant (Beta Vulgaris), Common name Chaqandar belongs to Chenopodiaceae family. They are like red beets in shape but have a larger white root and are inedible when harvested.
Its root contains 75% water, about 20% sugar, and 5% pulp. However, exact sugar content can vary between 12% and 21% sugar, depending on the cultivar and growing conditions. Beet is the only species of agricultural importance in this small family. Sugar is the primary value of beet as a cash crop. Its average weight ranges between 0.5 and 1 kg.
Why to grow sugar beet for sugar production?
Sugarcane is major and only sugar crop in Pakistan. Once The federal minister of agriculture has stated in the press that in view of the water problem, high water-requiring crop of sugarcane may be replaced with lower water-requiring crop of sugar beet as sugar requirement of country is very high and Pakistan is becoming a water scarce country we must adopt some alternative sugar crops. Sugar beet can be the best option due to some reasons like;
- Sugarcane is a high delta crop requiring intensive watering (30 times), whereas sugar beet a low delta crop and needs fewer watering (eight times).
- Sugarcane occupies land for 10-14 months while sugar beet only 4-5 months
- Sugar beet is salt tolerant crop and most of our soils are saline
- Insect/pest/disease attack on sugarcane is more as compared to sugar beet
- Fertilizer requirements for cane is greater than sugar beet
- Nutritionally both crops are identical
- Yield and sugar recovery from beet are same as from cane
- Sugar from cane is extracted by crushing while from beet is extracted by diffusion
Area and Production in Pakistan
In 2012 only two sugar mills, Al Moiz and Premier in KPK were producing sugar by beet slicing. Average yield is 35.0 t/ha and sugar recovery is 9.0-10% which is less than other countries. likewise, during the 2012-13 season, these mills processed 306,343 tons of sliced beet, producing 33,028 tons sugar and 12040 tons molasses. Latest figures were not immediately available.
According to knoema corporation US, In 2017, sugar beet production for Pakistan was 105,783 tones. Whereas Sugarcane production was 81.102 million tones sugar cane produced on an area over 1.313 million hectares in 2017-18.
KPK produces beet at commercial level, Sindh is the only other province where it is cultivated on a very small scale, while the initial technical evolution shows that agronomy wise the crop (sugar beet) can be grown as a winter crop both in lower Sindh and Punjab to be sown in October/November and harvested in April/ May after the cane crushing is over.
Sugar beet is a tough plant and adapted to various conditions. For maximum production temperature of 25 o C at day time and 17 o C at night is suitable with good sunlight of 16 h per day. Sugar beet is a temperate region crop and give root yield 100 t/ha and sugar recovery of 13-15%.
In Pakistan maximum growth is from February to April. Beet crop flourish best in loam’s and clay loam’s with a near neutral pH. Acidic conditions are unfavorable to its growth However, once established, sugar beet plants have a high tolerance against saline or alkaline conditions.
- Time of Planting
The best planting time of sugar beet is from mid to end of the October. Seed sowing at first week of October gives 64.3 t/ha root yield. Experiments shows that maximum seed germination is at 25 ◦C. Planting in November gives lower beet root yield as well as sugar yield compared to October planted crop.
- Selection of Variety
Most popular varieties are Kawe terma, Kawe Mera, Kawe Pura, KWS PAK-595, KWS PAK-691.
Varieties with higher beet root yield, sugar yield and particularly more disease resistant should be selected very carefully as it has a great economic impact on both farmer plus millers. In an Experiment by PARC and NARC in lower Sindh, Maximum beet yield was produced by SDPAK 03/06 followed by California,
Magnolia and SDPAK 09/07. In terms of sugar recovery, the varieties Magnolia, SDPAK 01/07, SDPAK 07/07 and SDPAK 09/07 performed better and were almost at par. While, the varieties California, Magnolia, SDPAK 03/04 and SDPAK 09/07 performed best about beet yield and sugar recovery in lower Sindh.
- Seed Bed Preparation
If the land is vacant in August-/September land preparation should be done in these months. Ploughing to 30-35 cm gives ideal conditions for its germination and growth. Cultivate the land properly, i.e. 2 times with cultivator and 1 deep plough. The soil should not be powdery.
If soil is clottier then seed may remain bare and that will result in poor germination. On the other hand, powdery soil may become compact and allow less seed germination. Soil should be porous and level so that water travels smoothly in the field. Ridges should be 50 cm apart.
- Planting Method
Single row, top seeding at 45 cm gives higher yield, due mostly to the higher plant population. With this method we can easily re-sow the seed and maintain the required plant population as well as harvesting is easy.
Use of beet planter saves time, labor and gives higher economic efficiency over manual sowing. With regarding double row method, row to row space should be 75 cm and seed sowing is on both sides of a ridge. Seed depth should not be more than one inch otherwise germination will be reduced.
- Seed Rate
Less seed rate results in lower plant population ultimately reduces the yield. So, farmers must use 1-1.5 kg seed/acre in order to achieve recommended plant population and maximum beet yield. Seed should be treated with Diathane M 45 @ 4 g/kg seed.
- Plant to Plant Distance
Plant to plant distance must be maintained up to 8-9 inches so that we can retain 80,000 plus plants/ha. If this distance is not maintained properly then it will affect the plant’s vegetative growth as well as root size. The ideal plant density is 87,500 to 100,000 per hectare.
- Plant Population
Plant population is one of the most important factors to determine crop yield. In order to maintain the plant population, check out the germination, if it is more than 80% then there is no need to re-sowing or transplanting.
But if it is less than required then re-sow the seed or transplant the plants from thick area to maintain plant density 87,500 to 100,000 per hectare. Dense population will reduce the yield as well as sugar content.
- Thinning and Transplanting
Thinning is done in order to maintain the proper plant to plant distance so that plant growth is vigorous and root size will be appropriate (1-1.5 Kg/plant). It must be done when germination is completed.
The gaps should also be filled at proper time i.e. right after 30-40 days of germination. In this regard we can transplant thinned out plants in gaps to avoid re-sowing.
Sugar beet is low delta crop (27-acre inches) requiring 8-10 irrigation during the growth period. It is sensitive to both extremes, drought as well as excessive moisture. The latter is harmful to root quality. On an average, fields should be irrigated at 2-3 weeks interval. Adequate water supply is especially important during the critical growth stages namely formative, leaf growth and root development.
If soil is clayey then stop irrigation 30-40 days before harvesting because this type of soil has more water holding capacity and crop does not face any stress. In other case if soil is sandy then irrigation stop irrigation 10-20 days before harvesting because sandy soil has lesser water holding capacity and crop may goes into water stress. If irrigation is not stopped before harvesting, it will cause in lesser yield as well as immature crop.
According to the Sugar crop research institute, Mardan, 90 kg nitrogen per hectare gives good yield. Phosphorous at the rate of 100 kg/ha. Usually, 5 bags of urea, 4 bags of DAP and 3 bags of SOP/hectare are recommended to provide the required amounts of nitrogen, phosphorus and potash nutrients for optimum growth.
Whereas full amount of DAP and SOP is applied at the time of sowing, urea may be applied in 3 split doses i.e. at sowing, after thinning and after earthing up.
- Weeding and Hoeing
Weeding and hoeing must be done at right time i.e. when vegetative growth is at peak and at the time of root formation. Knotgress, kmila, Bathu, Ludhri, and other rabi weeds are common in beet. Goltix @ 4-5 kg/ha as pre-emergence and Coltix@ 2.5 kg/ha at four leaf stage gives best results. Many other options are available.
- Control of Pest / Diseases
Most common diseases of this crop are Rhizomania, Cercospora leaf spot, Black leg Powdery Mildew and Downy Mildew. Rhizomania is a viral disease while other three are fungal and bacterial diseases. Seed should be treated with Diathane M 45 @ 4g/kg seed. Army Grasshopper. Cutworm, aphid and jassid are major pest of sugar beet.
If any insect/pest damages crop and damage is up to threshold level and there is a threat that it can damage the crop severely than apply the pesticide/fungicide immediately, it must be properly diagnosed first. Furthermore, If pest or disease is not controlled, then increase the dosage or change the chemical.
Most of farmers practice defoliation at early stage and they may remove photo synthetically active leaves which reduces 10 t/ha yield and 2-3% sugar content in beet. Removal of 3-4 older leaves is good it reduces respiratory losses.
Harvesting starts in May. Farmers should harvest their crop when they are sure that they can transport it to the mill within 72 hours of harvest. Separate green portion from beet otherwise there will be more respiratory losses.
Average yield is 35 t/ha, sugar recovery is 9% in Peshawar region. Sugar yield is 3.2 t/ha which is very low than potential of 8-9%.
- Sugar beet should be cultivated in colder regions of KPK, Sindh, Balochistan and Punjab where soil and temperature is suitable
- Beet processing units should be installed in mills where sugar beet can be cultivated
- Better varieties and cultivar should be developed according to climatic conditions of Pakistan
- Research for its adaptability and site-specific production technology is required
- Extension workers should create awareness among farmers about production processing storage and transport