Kalp Das, Ph.D. Scholar, 
(Department of Vegetable Science, P.A.U Ludhiana)

High-quality, genetically pure seeds are the fundamental necessity for farmers engaged in commercial crop production. These superior seeds adhere to established standards regarding germination, uniformity, genetic integrity, and freedom from seed-borne pathogens, among other specified criteria. The significance of planting materials and quality seeds in agriculture cannot be overstated, as they substantially contribute to achieving crop yields that can be elevated by as much as 30%. Therefore, seeds represent a pivotal input in augmenting the productivity of all crops. The timely availability of top-quality seeds is of utmost importance for ensuring the food security of India's growing population. The performance of all other agricultural inputs is largely contingent on the utilization of improved seeds, which can potentially be further enhanced to 45% through the effective management of other resources. Consequently, it is imperative to replace subpar seeds with high-quality seeds of high-yielding varieties.

Open-pollinated varieties of seeds hold particular significance for farmers, accounting for 70% of the total vegetable seed production. These seeds result from either natural or human-driven selection for specific traits, which are subsequently refined with each crop cycle while maintaining genetic purity through selective breeding and isolation. Bees or wind play a role in pollinating the flowers of open-pollinated varieties. These seeds are favoured by farmers over hybrid seeds because they can easily produce open-pollinated varieties with minimal effort by repeatedly planting their seeds. Additionally, open-pollinated varieties tend to be less susceptible to diseases due to minimal genetic variation among plants in the field when compared to genetically distinct hybrid varieties.

Carrots a crop that naturally undergoes extensive cross-pollination, necessitate additional attention and care in the process of seed production. Carrots can be categorized into two distinct groups based on their climatic preferences: the Asiatic type and the European type. In the context of Indian agriculture, it is advisable to focus on cultivating the Asiatic group when it comes to seed production.

Here are some notable Indian carrot varieties and their distinctive characteristics:

Pusa Rudhira: Developed by ICAR-IARI, New Delhi. Dark red roots with a self-core, 27 cm long and 3.4 cm diameter. Well-suited for NCR region, offering a 50% higher yield compared to the national check, Pusa Kesar.

Pusa Kesar: Deep red roots, rich in carotene. Matures in 80-90 days after sowing and is suitable for cultivation across India.

Pusa Meghali: Short tops, smooth orange-fleshed roots with a self-coloured core. Suitable for both early and late sowing, with a maturity period of 110-120 days. Ideal for Madhya Pradesh and Maharashtra.

Pusa Ashita: Late bolting tropical variety with roots that have a self-black core. Offers 30% higher yield than Pusa Kesar, making it suitable for the NCR.

Pusa Yamdagni: A temperate variety with orange roots, self-colored core, and medium tops. Matures in 90-100 days and is recommended for cultivation across India.

Pusa Vrishti: A heat-tolerant tropical variety suitable for early sowing from July in North Indian plains. Matures in 85-90 days and offers a yield of 250 q/ha.

Selection 223: Developed by PAU, Ludhiana, with orange roots and light orange flesh.

No. 29: Developed by PAU, Ludhiana, with long tapering and light red roots.

Climate Needs:
The Asiatic type of carrot, to ensure healthy vegetative growth and root development, thrives in cooler or moderately cool climates. When considering seed production, it's crucial to select areas with minimal rainfall during the summer, as a dry and warm atmosphere is essential for the proper maturation and drying of the seeds.

Land Prerequisites:
The seed plot should be meticulously maintained to be free from any unwanted variations, volunteer plants, and weed species. Additionally, the soil should have effective drainage.

Isolation Criteria:
In order to preserve the genetic purity (true-to-type characteristics) of the seeds, it is vital to adhere to the recommended isolation distances. This is because carrots are naturally cross-pollinated. Specifically, the seed field of a particular carrot variety must be isolated from fields that contain:
  • The same variety of carrot that does not meet varietal purity standards, and
  • Different carrot varieties growing alongside the specific variety.

Rouging, a practice in seed production, involves the elimination of plants that differ from the desired variety. In the context of carrot seed production, the following considerations apply to rouging:

1. Eliminate plants displaying foliage and flower colors that deviate from the characteristic features of the target variety.

2. Remove plants prone to bolting during the transition from the seed to the mother root phase, as well as those showing early bolting characteristics during the transition from the mother root to the seed phase.

3. Removing plants afflicted with diseases or infested by insect pests and eliminating stunted or deformed plants is essential. Additionally, after uprooting the mature roots, select only those that conform to the desired characteristics in terms of root shape, size, color, and discard any roots that are forked, cracked, light-coloured, differently coloured, rough-surfaced, highly hairy, or display green or purple shoulder color, as well as those that have suffered mechanical damage.

Main method of seed production of carrot in India:
The primary method employed for carrot seed production in India is the "Mother Root to Seed Method." This approach is chosen due to its lower susceptibility to root rot disease in transplanted roots. In this method, only carrot roots with a consistent core colour are planted, and the crown is left exposed. The process of seed production through the Mother Root to Seed Method involves two stages:

(A) Mother Root Production Stage - The initial step in the first season: Carrot seeds are sown in the first season to yield mother roots, known as stecklings. The procedure for steckling production is as follows:
  • Land Preparation: Carrot fields require regular soil pulverization, which is achieved through deep plowing, harrowing, and leveling. Deep and loose soil is necessary for optimal root development.
  • Fertilizer and Manure Requirements: Apply 15-20 tons of well-decomposed farmyard manure per hectare and thoroughly mix it into the soil before sowing.At the time of sowing, add 40-50 kg of phosphorus and potash per hectare.During the growing season, add 75-100 kg of ammonium sulfate per hectare, one or two times after weeding.
  • Seed Source: Obtain seed (Nucleus/Breeder's/Foundation) from an approved source recognized by the seed certification agency.
  • Seed Rate: A seed rate of 8-10 kg, which may vary depending on seed size, is adequate for sowing one hectare of land. The carrots produced from one hectare of land provide enough material for transplanting in 3-4 hectares of land used for seed production.
  • Sowing Time: The timing of carrot seed sowing depends on favorable climatic conditions and the duration of the carrot variety. Suitable sowing time typically falls between mid-July and mid-August.

  • Method of Seed Sowing and Spacing: The most effective method for ensuring proper root development in carrots is by sowing the seeds on double row ridges, rather than in a flat method. 
To implement this method:
  • Double row ridges, spaced 75 cm apart, are created.
  • Seeds should be treated with Thiram, Captan or Carbendazim at a rate of 2 grams per kilogram of seeds.
  • Seeds are sown in rows by hand and covered with soil.
  • Immediately after sowing, the field should be irrigated to maintain soil moisture until germination, which typically occurs in 7-8 days.
  • Thinning is essential for optimal growth, with a recommended distance of 6-7 cm between plants, considering a plant height of 5-6 cm.

Other key steps in carrot seed production include:
  • Regular irrigation at intervals of 8-10 days.
  • Frequent weeding and hoeing in the early stages, with 2-3 hoeings to control weeds effectively. Earthing up by the end of September or early October helps maintain a clean crop through autumn.
  • Application of Rogor 30 EC 0.05% solution for pest control, targeting carrot weevil, spotted leaf hopper, and carrot rust fly.
  • Uprooting the plants when their roots have fully developed.
  • Selection of roots for transplanting based on characteristics such as top (short or heavy), skin color (red, purple, black, creamy), shoulder color (greenish ones to be discarded), root shape and size, flesh color, and core size and color. A small and self-core color core is preferred, with the same color as the flesh (phloem).

(B) In the second season (Autumn season) of the Mother Root to Seed Production Stage, the following steps are involved:
  • Land preparation through repeated plowing, harrowing, and leveling.
  • Selection of roots for steckling preparation, a crucial stage for producing genetically pure and high-quality seed.Preparation within a 90-day timeframe is essential for the second season of Mother Root to Seed Production. One acre (0.25 hectares) of mother roots is adequate for planting four acres (1 hectare) dedicated to seed production. These roots must conform to the desired characteristics, with selection based on uniformity in shape, size, and color. True-to-type roots are chosen, and stecklings are prepared by trimming 3/4 of the root and 2/3 of the leaf portion. This practice enhances steckling establishment, resulting in increased shoot growth and, consequently, higher seed yields.
  • The transplanting process involves placing carrot roots at a spacing of 75 cm between rows and 30 cm between individual plants. Regarding intercultural operations, one weeding in March and another hoeing and earthing up in April-May are necessary.
  • Rouging, the removal of unwanted plants, should be carried out during the bloom stage. Early bolting and off-type plants need to be eliminated.
  • Harvesting is performed manually when the secondary umbels have fully ripened (turned completely brown), and tertiary umbels start to brown. Harvesting begins when 60-70% of the seeds have turned brown. Given the uneven ripening of the carrot crop, multiple pickings are required.
  • After sun drying, the seed heads are threshed and cleaned. Subsequently, the seeds are hand-rubbed to remove surface impurities and then sorted using sifters and sieves.
  • The Seed yield per hectare typically ranges from 500 to 600 kilograms. For Storage, it is advisable to maintain the seed at 8% moisture content.

In the context of carrot seed production, there are a few additional key points to be noted:

1. Genetic Purity: Ensuring the genetic purity of carrot seeds is of utmost importance. This is achieved through careful selection, isolation, and rouging practices. Varieties should maintain their true-to-type characteristics.

2. Disease and Pest Management: Monitoring and controlling diseases and pests is crucial to safeguard the crop's health and seed quality. Practices such as the application of appropriate pesticides, regular inspection, and removal of diseased plants are essential.

3. Timing: Timeliness in various stages of seed production, including planting, thinning, harvesting, and processing, is critical. Proper timing ensures optimal seed yield and quality.

4. Quality Standards: Adherence to seed quality standards and certification processes is essential to ensure that the seeds meet the required criteria for germination, uniformity, and freedom from pathogens.

5. Local Adaptation: Choosing carrot varieties that are well-suited to the local climate and soil conditions can contribute to successful seed production.

6. Record Keeping: Maintaining detailed records of the seed production process, including planting dates, weather conditions, and any issues encountered, can aid in improving future seed production cycles.

7. Storage and Packaging: Proper storage conditions, such as maintaining the recommended moisture content and protecting seeds from pests, are essential for preserving seed quality. Packaging should also be done carefully to prevent moisture and temperature fluctuations.

8. Training and Education: Ensuring that farmers and workers involved in seed production are well-trained and educated about best practices, disease identification, and seed handling is critical for successful outcomes.

9. Regulatory Compliance: Complying with agricultural and seed production regulations, including sourcing seeds from approved sources, is important to maintain seed quality and purity.

10. Diversification: Diversifying carrot varieties and practicing crop rotation can help reduce the risk of disease buildup and maintain soil health.