Critical Limit Of Zinc In Soil

Introduction rice is a stable food for about 50 percent of the world s population that resides in asia where 90 per cent of the world s rice is grown and consumed.

Critical limit of zinc in soil.

Soil z n ppm critical limits of zn in soil fig. The dtpa extractable zn was positively and significantly correlated with cec organic carbon and clay contents and negatively correlated with ph silt and sand contents of soil. It is an important stable food that provides 66 70 per cent body. A pot culture experiment was conducted to determine the critical limit of zn for rice grown in veeranam command area vertisol and entisol.

Rice soil critical limit zinc applications. It has also been reported to cause contamination of soil water and food chains in human beings zn deficiency is associated to diet quality exacerbated by zn deficient soils 4 5. An experiment was conducted during 2016 2017 to study the critical limit of zinc in soil and plant. The soil contained caco3 0 33 7 54 ph 6 2 8 8 ec 0 27 1 6 dsm 1 and organic carbon 2 7 11 4 g kg 1.

The available zn content of soils was estimated by seven extractants and the amount of zn extracted followed the order of 0 005 m dtpa ph 7 3. Critical limits of zinc in plant at 30 das. A study was conducted in 22 alluvial soils of west bengal india to estimate the critical limit of zn in soil and rice plant for predicting the response of rice oryza sativa to zinc application. Zinc deficiency is also noticed in the soil derived from parent.

The treatments consisted 0 2 5 and 5 0 kg zn ha 1 as znso4 7h2o and recommended dose of nitrogen phosphorus and potashas urea single super phosphate and muriate of potash were used. However a substantial amount of average dry matter yield decreased with increasing levels of applied zinc fertilizer in the soils containing zn above critical limit up to 5 0 mg zn kg 1 soil. Som and on organic soil s. Critical limit of 20 mg zn g dw at high level of p application 27 mg kg 54 55.

Among three zinc extrantants dtpa hcl and ammonium acetate only dtpa zinc extractant was significant and positively correlated with bray s per cent yield and chemical properties such as ph o c and available nitrogen. Pea pisumsativum l cv. The bray s per cent yield ranged from 29 12 to 126 36 and was positively correlated with available zn r 0 93 and plant tissue zn r 0 91. The critical limit of zinc in soil and plant was found to be 0 64 and 22 0 mg kg 1 respectively.

Among three extractants zn. Rachna was taken as the test crop.