Poly Chem Tech

Sarigam, Vapi, Gujarat

Manganese deficiency is most often seen on well drained neutral or calcareous soils but heavy fertilizer usage can induce it in other soils, particularly after heavy applications of lime.

Many vegetable crops are affected with onions, beetroots, parsnips, cabbages and cauliflowers, tomatoes and pumpkins the most susceptible.

Deficiency is controlled by using manganese sulphate as a soil applicant or a foliage spray.

Manganese (chemical symbol Mn) deficiency occurs in a wide range of crops with onions, beetroot, parsnip, cabbage, cauliflower, tomato and pumpkin the most susceptible. This deficiency is most common on alkaline soils (high pH), particularly if the irrigation water contains high levels of bicarbonate. Manganese is needed for a number of plant functions including chlorophyll synthesis. It is a partially mobile element in the plant so symptoms may first appear in the youngest or oldest leaves.

Manganese deficiency is controlled by using manganese sulphate (MnSO4 .7H2O) as a soil applicant or a foliage spray. Chelated forms of manganese can also be used as a foliar spray although this treatment is more expensive.

Ammonium sulphate is one of the oldest of N and S-containing fertilizers, and is still popular around the world. Ammonium sulphate is mostly produced as a co-product of other industries. An estimated 70% of global output originates from the production of caprolactam, an intermediate for the manufacture of synthetic fibers. A small amount is recovered from coke oven gas, with most of the remainder produced synthetically from sulphuric acid and ammonia. The product is used directly or for blending with other fertilizers. Improvements in the ammonium sulphate formulation processes allow for increasing shares of larger-sized granular material, which is easy to handle and suitable for bulk blending. This has greatly increased application options and spreading performance. Ammonium sulphate is also popular in India in the manufacture of compound fertilizers, now deliberately being added to increase their S content.

The main advantages of ammonium sulphate are low hygroscopicity and chemical stability. It is a good source of both N and S. Its use may be undesirable in acidic soils already in need of liming and when it is applied at nitrogen rates. Also, when applied as direct application as an N source, much more S is applied incidentally than is required by most crops.

Ammonium sulphate now can be obtained as a granular material, which is easy to handle and suitable for bulk blending with other fertilizer materials. Segregation problems can occur in bulk blends when its product size is not well matched with those of N, P, and K materials. This difficulty can be minimized by carefully controlling uniformity and sizing of ammonium sulphate used in blends.

It can also be used in clear liquids to make solutions of fertilizer containing N and S. Sulphur concentrations in solutions based on ammonium sulphate can vary from 1%-9%. In NPS blends formulated with ammonium sulphate, the usual S concentrations range from 1% to 3%.

Copper (Cu) is one of the micronutrients or trace elements that are essential for the healthy growth of plants and animals. In India, deficiency occurs less commonly in crops than does zinc, but more often than iron or manganese. Deficiency most commonly occurs on sandy soils, particularly if low in organic matter. Crops differ in their sensitivity to copper deficiency. Copper responsive crops include oats, wheat and lucerne, whilst potatoes and soybeans are less likely to respond. Pastures on sandy soils, and animals grazing these pastures, may also suffer from copper deficiency.

Copper sulfate (CuSO4), containing 24 % Cu. Crystal grades of this product have been used in the past, for dry application to the soil. Little use is made of it in India at the present time. The fully hydrated copper sulfate pentahydrate salt is used where copper is to be applied in solution