ISABGOL (plantago ovata Forks.). It is an annual stem-less herb, a native of Persia, now grows as a cash crop on about 16,000 ha in the Mehsana, Palampur and Banaskantha districts of Northern Gujrat, India is the largest producer of isabgol and exports seed and huskworth Rs 25 million annually. The husk is the rosey-white membranous covering of the seed which constitutes the drug and is given as a safe laxative, particularly beneficial in habitual constipation, chronic diarrhoea and dysentery.
Isabogal is an irrigated rabi crop which remains in the field for about 4 months. The crop is grown in marginal, light, well-drained sandy-loam to loamy soils having pH between 7 to 8. It requires a cool climate and dry sunny weather or light showers cause seed shedding.
After harvesting the kharif crops,e.g. jowar(Sorghum vulgare), the land is brougt to fine tilth and laid out into beds of convinient size for irrigation. It is preferable to mix with the soil 15 cartloads of well-rotted farmyard mannure per hectare during the preparation of the land.The optimum sowing time is early November ; sowing however, is extended till the end of December, but the delayed sowing decreases the yield. The seed rate is 7.8 kg per hectare. Seeds are small and light about 6000 to a gramme and are sown by broadcast. They are covered thinly by raking the soil. A light irrigation is given immediately. Germination starts in 6 to 10 days and the crop is given the second irrigation after 3 weeks and a third one at the time of the formation of the spikes ; thus the crop needs 6 to 7 irrigations.
Isabgol makes a moderate demand for nutrients. Usually,25 kgof each N and P per hectare is given at plantation.The crop is given 1 or 2 hand-weedings during the entire growing period. The plants are about 50 cm high andeach plants gives out between 25 to 100 tillers,depending upon tje fertility of soil and wheather conditions. The plant bears the flowering spikes in about 60 days after sowing and matures in the next 2 months.The yellowing of the lower leaves is an indication of maturity,confirmed by pressing a spike between two figers when the mature seeds come out. The crop is harvested close to the ground in the early morning hours to avoid looses owing to seed shedding.The harvested material is stacked for 1 or 2 days,made to be trampled by bullocks, winnowed,and the seperated seed crop is collected . A boldseeded crop fetches a better price.
The seeds are processed through a series of grinding mills to seperate the husk, and about 30 per cent husk by weight is thus recovered . The husk contains a mucilaginous substance.
Powdery mildew sometimes attacks the crop and is brought under control by spraying the crop with wettable sulphur, e.g. ‘Karathen’ and ‘Sulfex’ two or three times at 15-day intervals after the apperance of infection. White grubs are reported to damage the roots ; soil treatment with 5 per cent Aldrin or Lindane to protect the crop is given at the time of the last ploughing during the preparation of the field.