Cultivate cassava to get a good yield with high quality in less water

The problem of water in agriculture is increasing day by day. The water requirement of each crop should be estimated to deal with the water shortage in the near future and accordingly irrigation should be designed and suitable water-saving measures should also be adopted. Accurate use of water, as well as nutrients, is the need of the hour to improve water and nutrient use efficiency. Cassava (Manihot esculenta Crantz) is a major tropical tuber crop, important in food and nutritional security in rural livelihoods. plays a role. It is one of the world’s most important food crops after rice, wheat, and maize, but is ahead of potatoes in terms of the total area planted. Biosoilz

More than a food crop, the industrial potential of cassava is nowadays well recognized for use as cattle feed in addition to the production of native and modified starch, and bioethanol. In India, cassava is cultivated in about 0.16 million hectares, mainly in the states of Tamil Nadu, Kerala, Andhra Pradesh, Maharashtra, and North Eastern states with a total production of 5.04 million tonnes. India ranks first in terms of cassava productivity (30.75 t/ha) compared to the world average of 10.7 t/ha (FAO stat, 2020), largely attributed to improved varieties and agricultural technologies, especially irrigation. Is. Cassava is grown under protective irrigation and fertigation in the industrial areas of Tamil Nadu and Andhra Pradesh.

Whenever cassava is grown under irrigated conditions, especially in industrial areas, fertigation can also be done with micro irrigation to realize the full tuber yield potential of cassava.

Cassava – food and nutritional security crop

While cassava has major food value in Kerala and the north-eastern states of India, in other states such as Tamil Nadu, Andhra Pradesh, and Maharashtra, it is mainly used as an industrial raw material.

The major biochemical constituents in cassava are storage carbohydrates and starch, which account for 65–70% of the dry matter. Tubers also contain small amounts of sugars, minerals, vitamins, fats, fiber, and proteins. Tubers typically contain 40.0% dry matter, while leaves contain about 22.0% dry matter. Cassava has very low sugar levels (about 10.5 g/100 g), with sucrose being the main ingredient. Other sugars such as glucose, fructose, and maltose are also present. The amount of crude fiber varies from 1 to 2 g / 100 g of dry matter depending on the maturity of the tuber. Dietary fiber, which includes lignin, accounts for about 5% of the dry matter in tubers. Cassava tubers are rich sources of ascorbic acid and B-vitamins are also present in good amounts. Some varieties with yellow tubers are good sources of beta carotene. The major minerals present in tubers are calcium and phosphorus.

Why is irrigation needed in Cassava?

In Kerala and the northeastern states, cassava is traditionally grown as a rainfed crop and the tubers are mainly used for human consumption. Although the crop is reported to be drought tolerant, field trials have proven that it responds better to both water and nutrients. With the growing demand for cassava as an industrial crop for starch extraction, its cultivation has also been extended to non-traditional areas where rainfall is comparatively low or limited to a few months in a year. Therefore, in regions such as Tamil Nadu and Andhra Pradesh, where the tuber is used for industrial purposes, it is grown as a commercial crop under irrigated conditions, moreover, several short-duration varieties are now available which are 4- Matures in 6 months. Therefore, there is a possibility of growing two crops in a year, especially where irrigation facilities are available. In addition, the crop is light-sensitive and can be grown throughout the year regardless of the season, provided soil moisture is ensured, several studies have shown that when cassava is grown under rainfed conditions, it is less prone to drought. Supplemental irrigation during the period can give higher tuber yield than rainfed crops. Irrigation experiments carried out at ICAR-CTCRI have shown that irrigation can double the yield of tubers in comparison to unirrigated control at the level of available moisture deficit of about 25%. Is.

Major Growth Stages of Cassava

There are mainly six stages of development in the cassava life cycle. This period may vary slightly depending on the duration of the varieties. Varieties can be either of short duration which matures within 5-7 months or can be of long duration which takes 8-10 months to maturity.

  • Sprouting (5-20 days)
  • Leaf and root system development (20-90 days)
  • Canopy Establishment (90-180 days)
  • Tuber initiation (40-60 days)
  • Tuber development (60-240 days)
  • Tuber maturity (150-300 days)

Water requirement of cassava

The water requirement of a crop will vary widely according to the prevailing agro-climatic conditions. Cassava requires adequate moisture for germination and subsequent plant establishment

The initiation period of the tuber has also been found to be critical and the crop needs irrigation if rainfall fails. Withholding of irrigation at least 30-45 days before harvesting can effectively mobilize accumulated carbohydrates from stem to roots. Adequate moisture during the growing phase of the tuber ensures efficient photosynthesis and good yield.