Welcome to Directorate of Arecanut and Spices Development
Climate: It is a cold loving crop and mainly grown during rabi season in India. In some pockets of the country, it is also grown as kharif crop. Moderately cool and dry climate favour good plant growth and flowering. Avoidance of high humidity especially after flowering is beneficial. Continuous moist and cloudy weather invites insect – pests and a number of diseases. It needs a temperature between 15-27 0C with relative humidity of 60-70% during its growth period and requires preferably warm weather during seed development. However, the crop has moderate level of tolerance to drought and possesses wide climatic adaptability, as it can be grown in kharif season also.

Soil: Ajwain is well adapted to a wide range of soils but grows well on well drained loamy soils. Organic matter rich clay-loam soil may also be used provided adequate drainage facilities are available. However, the crop does not thrive well in sandy or gravely soils. Owing to high moisture retention, the heavy soils are ideally suited for rainfed cultivation of ajwain. Although the crop is tolerant to salinity but always gives higher yield with better quality of leaves in neutral soils having a PH range from 6.5 to 7.5 .Hence , its cultivation should usually be avoided in problematic soils, i.e. saline, alkaline and acidic one.

Improved varieties:
(A) Rajasthan: Ajmer Ajwain -1,Ajmer Ajwain 2 , Ajmer Ajwain-93, Pratap Ajwain- 1
(B) Gujarat: Gujarat Ajwain- 1
(C) Andhra Pradesh : Lam selection 1 and Lam selection 2 , R.A. 1-80  and R.A.19-80,

Preparation of land: The soil should be brought to fine tilth for good germination and growth.The first ploughing should be done by deep soil turning plough followed by 2-3 light ploughing by harrow or cultivator. Each ploughing should be followed by planking to conserve the moisture. In the termite prone areas add 20-25 kg/ha of  quinalphos 1.5% or methyl parathion 3% powder at the time of last ploughing.There should be good moisture in the soil for better germination of seed.

Sowing time: Ajwain is a cold loving crop and is mainly grown during rabi season in India. In some pockets, it is also grown as kharif crop. As a rabi season crop, it is sown in the months of September and October in northern plains, whereas, for kharif season crop, it is sown from July to August. In southern part of India, particularly in Andhra Pradesh, Karnataka and Tamil Nadu, Ajwain is usually sown in the middle of August and harvested around December and January. The early crop of Ajwain is mostly grown as rainfed and is sown during August, whereas the main season crop is sown as rabi season crop during September-October. For realizing yield, it is better to adjusted sowing time in such a way that the seed development and seed maturity phase coincide with a dry and rain free period.

Seed rate: The quantity of seed required for the sowing of unit area depends on the cropping season for which the crop is sown. In order to sown one hectare area, about 2.5 – 3.0 kg seed of ajwain for rabi season crop and 4-5 kg for kharif crop season is required. The initial soil moisture at the time of sowing should be adequate to ensure satisfactory germination.

Seed treatment : The use of bioinoculant Azospirillum or Azotobactor as seed treatment before sowing has proved beneficial in getting higher yield. Seed should be treated with bavistin or captan or thiram @ 2.0- 2.5 gm/kg seed for the control of seed and soil borne diseases.

Sowing method : The seeds are sown by broadcasting method or drilled in rows 45 cm apart under irrigated conditions and 30 cm under rainfed production system. The seed germinates in about 10-12 days.The plant to plant spacing should be maintained to 20-30 cm. Ajwain is generally sown by broadcasting method but to facilitate inter culture operations, line sowing is appropriate. The Ajwain seed is small in size thus depth of seed should be kept around 1.0 to 1.5 cm in the soil for getting good germination. It is better to maintain uniform spread of seed through mixing of seed with dry sand before sowing.

Manures and Fertilizers: In general, for raising good irrigated crop of Ajwain, 10 tons of well decomposed FYM. or compost may be applied and evenly spread in the field before ploughing. At the time of last ploughing 30 kg N, 40 kg P2O5 and 30 kg K2O /ha may be applied in soils. An additional dose of 30 kg nitrogen may be given in two equal splits one at 45 days after sowing and second before flowering. In the rain fed farming area of ajwain 10 ton of well decomposed FYM or compost may be mixed in soil once in 2-3 years. In addition to this 40 kg N, 20 kg P2O5 and 20 kg K2O /ha should be applied at the time of sowing.

Irrigation : Ajwain is cultivated both as rain fed and irrigated crop. In irrigated production system about 4-5 irrigations are required. If initial moisture is less after sowing, a light irrigation is given after 4-5 days to facilitate germination and checking crust formation. Depending on climate and soil type subsequent irrigations are applied at interval of 15-25 days. Application of irrigation at 0.8 IW/CPE ratios has been found better for realising higher yield.   

Weed management: Initial growth of Ajwain crop is very slow; therefore, it is necessary to keep the field free from weeds. A total of 2-3 manual weedings and hoeings are required, the first weeding should be done after 30 days of sowing accompanied by thinning from rows after maintaining suggested intra row spacing. The subsequent weeding is done at 30 days intervals as per requirement. Weeds can also be controlled by a pre-emergence application of Pendimethalin @ 1 kg /ha after sowing or Oxadiargyl @ 75 g/ha + one hand weeding at 45 DAS is good techniques for weed control in ajwain. Care must be taken that there is sufficient moisture in the soil at the time of application of weedicides for enhancing effectiveness of weedicides.

Plant protection: Ajwain crop is generally less affected by insect-pests and diseases. However, sporadically crop is harmed by aphids, jassids, seed bug, midge, root rot and powdery mildew.The plant protection measures should include selection of resistant varieties, crop management practices such as time of sowing, balanced nutrition, crop rotation, green manuring etc. for reducing the incidence of diseases and pests and adoption of control measures.

Insect-pests

Aphids: Some times ajwain crop is infested by aphid. It colonies the plant at  vegetative stages. Affected leaves and tender stem  get devitalized and dried later on. 

Control
•    Spray Imidachlorprid (0.005%),Thiomethoxam(0.025%),Dimethoate (0.33%). Repeat second spray after 10-15 days if necessary.
•    Applications of resin soap or Neem Seed Kernel Extract (NSKE) 5%, Neem oil (2%) at early stage of population build up give good result.

Diseases

Root rot (Rhizoctonia solani Kuhn.): This is a soil–borne disease. The symptoms include varying degrees of rotting of the root leading of foliage yellowing generally in 30 – 45 day–old plants. The affected plants later on wither and dry up. It is a serious problem in ajwain growing areas and drastically reduces the yield.
Control
•    Seed treatment with Thiram or Captan @ 3 g/kg of seed.
•    Soil application of neem cake @ 150 kg/ha and seed pelleting with antagonistic fungi like Trichoderma  viride, T. harzianum (Talc based formulation @ 6 g/kg of seed) can be used to mange the         disease.
•    Drenching of Carbendazim (0.1%) once at initial appearance of disease and after one month.
•    Deep summer ploughing of field and adoption of crop rotation practice.
•    Use of bio-inoculants Azospirillum or Azotobactor plays significant role in reducing incidence of root rot to 8.2%.

Powdery mildew :The disease generally appears late in the season and is of minor importance. The symptoms include the appearance of whitish fungal growth on leaves. The disease becomes serious at temperatures between 150 – 250C and at a relative humidity of above 60%.
Control
•    Dusting with Sulphur (25 kg/ha) or by spraying wettable Sulphur or Karathane (0.1%) twice at flowering stage at 15 days interval.

Harvesting and yield: The crop matures in 130-180 days depending upon the variety and season. The harvesting is usually done from February to May. At maturity flowering ceases and seed begin to develop and become brown in umbels. The crop is harvested with sickles or manually and stacked for drying, keeping the bundles upside down and then threshed to separate the fruits by beating with sticks. An average yields of 4-6 q under rain fed and 12-15 kg/ha under irrigated conditions could be obtained.

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