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Nickel is an essential micronutrient for leguminous plants. It has a large range between limiting and toxic levels. A pot experiment was conducted on two dominant soil series of Jharkhand i.e., Upland [Sidhamantoli (ST-5)] and Lowland [Tetratoli (TT-5)]. Five application levels of Ni, viz. 0.0, 2.5, 5.0, 10.0 and 20.0 mg kg−1 with pea (Pisum sativum L.) as test crop were arranged in three blocks in a glass house. An increasing trend of pea dry matter was observed with increasing Ni application level up to 10.0 mg kg−1. Nickel content in pea plant over control was found 1.36 to 2.53 folds higher with Ni application 2.5 to 20.0 mg kg−1. Accumulation of Ni in soil of Sidhamantoli series (upland situation) was noticed 1.11–4.29 mg kg−1 in top and 1.31–5.68 mg kg−1 in bottom of the pot, while in Tetratoli soil series (low land situation) Ni content was found 1.40–5.35 mg kg−1 in top and 1.25–4.95 mg kg−1 in bottom soil. Nickel application stimulates Plant growth parameters and that gradually increased with increasing Ni application levels up to 5.0 mg kg−1 in Sidhamantoli and up to 10.0 mg kg−1 in Tetratoli soil series, while at 20 mg kg−1 Ni application in both soil conditions showed negative effect. So, appropriate precaution should be maintained in application of Ni in leguminous plants and fixed a threshold value of Ni application level 5.0 mg kg−1 in upland Sidhamantoli (ST-5) and 10.0 mg kg−1 in low land Tetratoli (TT-5) soil series of Jharkhand plateau. [ABSTRACT FROM AUTHOR]

The importance of molybdenum (Mo) for plant growth is disproportionate with respect to the absolute amounts required by most plants. Chickpea (Cicer arietinum L.) cv. K-75 plants were raised in refined sand in glasshouse at graded levels from 0.002 to 1 µM for 100 days. Mo deficiency symptoms appeared as interveinal chlorosis of middle and old leaves. Compared with the control (0.2 µM Mo), dry matter, yield and seed protein decreased at low and excess Mo. The concentration of Mo in leaves and seed as well as the activity of nitrate reductase (NR) increased with an increase in Mo supply. The activities of antioxidative enzymes stimulate at both low and excess Mo supply. Low and excess Mo decreased the lipid peroxidation status in chickpea leaves, suggesting its antiperoxidative nature. The values of deficiency, threshold of deficiency and threshold of toxicity of Mo were, respectively, 0.38, 1.2 and 15 µg g−1in leaves of chickpea. [ABSTRACT FROM AUTHOR]

Pot-culture studies of intensive cropping without potassium (K) application, taking three successive crops of rice on Sonakhali (Inceptisol) and Ranibundh (Alfisol) soils, revealed that all the forms of soil K declined after the third crop compared to the corresponding initial soil status. A similar trend was also found for nonexchangeable K extracted sequentially and termed as Step K and CR-K (constant rate K). The CR-K contents showed little variations with cropping. Except for the potential buffering capacity of the soil for K at equilibrium (PBCK0) values, all the quantity/intensity (Q/I) parameters, namely activity ratio of potassium (ARKe), labile K (–ΔK0), specifically held K (KX), and total labile pool of K (KL) values, decreased in both the soils as they were subjected to repeated cropping. The PBCK0values changed to a smaller extent in both the soils. In both soils, the threshold levels for release of intermediate K in terms of activity ratio, exchangeable K, and K concentration in soil solution decreased after the third cropping as compared to the initial status. The dry-matter weight of rice, K concentration, and K uptake decreased with the cropping sequence. The difference in values of each parameter between initial status and the third crop was much wider in Inceptisol than in Alfisol. [ABSTRACT FROM AUTHOR]