Tomato (Solanum lycopersicum L.), which is an excellent vegetable to provide important nutrients and antioxidants for human health benefits, is sensitive to boron (B). Influence of B application for improving physical attributes, proximate composition, antioxidants, and mineral composition of tomato, by synchronising B requirements of the crop is not reported yet. This study critically evaluated influence of five B application protocols with seven tomato genotypes on 28 fruit quality attributes and two important fruit quality indices. In-depth evaluation showed that B directly influenced fruit pericarp thickness, pH, phenol, Zn, Cu, and B content. Boron application (2.0 kg ha(-1)) to soil at planting plus foliar spray (0.125 kg ha(-1)) at pre-flowering stage of tomato was the best. It improved tomato fruit quality by improving physical attributes (6.1-33.1 %), proximate composition (7.8-49.0 %), antioxidants (16.7-207.5 %), and mineral nutrients (9.6-146.8 %) content of tomato fruit. This, in turn, led to an improvement in fruit quality indices for both fresh consumption and processing by about 31.0 %. Overall, the order of the genotypes in terms of their B responsiveness was Pusa Ruby > 2016/Res-3 > Pathar Kuchi > 2016/Res-6 > 2016/Res-5 > 2016/Res-1 > 2016/Res-4. Results of the study thus suggest that cultivation of the identified promising genotypes of tomato with optimised B application could produce superior fruit quality in intensively cultivated vegetable growing regions.

Potato is an important vegetable crop as well as the most important staple food crop in India after rice and wheat. Being one of the cheapest sources of energy rich natural nutritive foods, potato contains several antioxidant in minute quantities. Potato is highly sensitive to Zn deficiency and the yield and quality of tuber is affected in Zn deficient soils. Establishing the critical limit of Zn in soil and plant is highly essential for optimizing the Zn fertilization dose. Therefore, the present study was conducted to evaluate the critical limit of Zn in soil and plant. To assess the critical limit of Zn, four graded doses of Zn was administered in the form of ZnSO4.7H2O like Zn0: 0 kg Zn ha-1, Zn5.0: 5 kg Zn ha-1, Zn10.0: 10 kg Zn ha-1 and Zn20.0: 20 kg Zn ha-1. The result indicated Zn concentration below 0.49 mg kg-1 in soil showed Zn deficiency while the Zn concentration below 7.0 mg kg-1 would indicate deficiency of Zn in potato tuber in respect of yield and quality of potato. Similarly, the critical concentration of Zn in potato shoot was found to be 32.7 mg kg-1 (average of values determined by both graphical and statistical method). Below this concentration, it was considered to be deficiency of Zn in potato shoot which can influence yield and quality of potato. Moreover, the application of Zn @ 20.0 kg ha-1 showed higher response to biomass yield of potato and may be recommended for quality tuber production.

Tomato ( Lycopersicon esculentum L.) is a sensitive crop to B deficiency, but information on critical concentrations of the element in plant tissues and soils for the crop is scarce. An experiment was, therefore, undertaken to assess available B content in the Gangetic alluvial soils ( Entisols and Inceptisols ) for tomato and to determine critical limits of B in soils and leaves of tomato involving second order polynomial curve fitting. Soils and tomato leaves were collected from 94 tomato growing fields. Soils were analysed for hot-calcium chloride (HCC), potassium dihydrogen phosphate (PDP), tartaric acid (TA) and hydrochloric acid (HCl) extractable B and tomato leaves for B concentration. Among the four extractants, HCl extracted the highest amount of B followed by HCC > TA > PDP. Extractability of the extractants for B was explained mechanistically with soil properties. Hot-CaCl 2 showed stronger relationships with soil properties, tomato fruit weight and leaf B concentration, and thus proved to be the superior over other extractants for assessing available B status in soil for tomato. Critical limits of HCC extractable B were 0.51 and 0.52 mg kg −1 and of mature tomato leaf B concentration were 40.5 and 37.5 mg kg −1 in Entisols and Inceptisols , respectively. The method of determining critical concentrations of B in soils and plants involving polynomial equations with non-destructive on-field samples was efficient for delineation of B deficiency in both Entisols and Inceptisols . Multi-criteria based novel approach established HCC as the best extractant for assessment of available B in soils.

Brinjal is a widely grown vegetables. A pot experiment was conducted to study the effect of farmyard manure (FYM), Zn and B application on fruit yield, their uptake and ascorbic acid contents of brinjal where two levels of FYM (no FYM and 5 Mg ha(-1)), four levels of Zn (no Zn, 5 kg Zn ha(-1) as basal, 10 kg Zn ha(-1) as basal and 5 kg Zn ha(-1) as basal + foliar spray of Zn twice @ 0.5% ZnSO4.7 H2O) and three levels of B (no B, 1 and 2 kg B ha(-1)) were applied in a factorial controlled randomized design. Zn @ 10 kg ha(-1) through basal and soil + foliar application enhanced the fruit yield over Zn @ 5 kg ha(-1) and control. Foliar spraying of Zn and basal applied Zn enhanced the Zn uptake in fruits to 2.0-2.25 fold, while 2 kg B ha(-1) application enhanced the uptake by B of two-fold irrespective of FYM application. A higher B use efficiency was recorded with 1 kg B ha(-1) application than 2 kg B ha(-1). Basal application of Zn and B, in addition to the foliar spray of Zn, is recommended to correct Zn and B deficiency in brinjal.

Globally, soil degradation is an important issue for sustainable crop production. Soil quality indicators are the soil attributes that address the ecological functions of soil. Therefore, indicator-based soil quality assessment has been emphasized for quantifying the relative soil quality changes in different nutrient management systems. Soil quality underthe rice (Oryza sativa L.) and wheat (Triticum aestivam L.) cropping system was assessed using a modified “Soil Management Assessment Framework (SMAF)” model. Soil’s physical, chemical, nutritional, and biological indices were analyzed for different nutrient management strategies, viz., inorganic fertilizer (NPK), NPK + 7.5 Mg ha−1 farmyard manure (NPKF), NPK + 10.0 Mg ha−1 paddy straw (NPKP) and NPK + 8.0 Mg ha−1 Sesbania sesban L. green manure (NPKG). Nutrient management strategies significantly influenced soil quality indices. NPKF showed the highest SMAF score for soil physical quality index followed by NPKP > NPKG > NPK and control; whereas the score of soil chemical quality was greater in NPKP followed by NPKF/NPKG > NPK > control (p > 0.05). Overall, the soil nutritional quality index was greater in NPKF (0.96) followed by NPKG > NPKP > NPK, and the least was in control. The SMAF score of soil biological quality index was highest in NPKF compared to NPKG > NPKP > NPK > control. The wholesome index of SMAF (SQI) was developed withthehighest score in NPKF (0.94) followed by NPKG (0.90) > NPKP (0.89) > NPK (0.79) > control (0.71). The β-glucosidase activity, mineralizable C, KMnO4 oxidizable N, microbial biomass C, and total water-stable aggregates explained 82% variability in the dataset and represented a good agreement with system yield (R2 = 0.89, p < 0.05). This study concludes that the conjunctive application of NPK with manures restores the overall soil quality more than other management practices, and thatthe SQ indices can be utilized for screening the best management practices for rice-wheat and other similar cropping systems.

An experiment was conducted to understand plant available B status in Entisols and Inceptisols of the Gangetic alluvial plains for cauliflower and to determine critical concentrations of B in soils and plants of cauliflower by using polynomial equations. Soil and cauliflower crops (plant and curd) were collected from 81 cauliflower growing farmers' fields. Soil samples were analyzed for available B by using hot-CaCl2 (HCC), KH2PO4 (PDP), tartaric acid (TA) and HCl (HCl) and cauliflower crop samples for B concentration. Hot-CaCl2 and dilute HCl extracted a higher amount of B followed by TA and PDP in decreasing order. Better relationships of HCC and HCl with soil properties, cauliflower curd and plant weight and B concentration in crop tissues proved their superiority over TA and PDP for assessing B availability for cauliflower in soil. The critical level of adequate HCC and HCl extractable B concentrations were 0.53 and 0.54 mg kg(-1) in Entisols and 0.57 and 0.58 mg kg(-1) in Inceptisols, respectively. Similarly, critical B concentration in cauliflower plant was 21.5 and 23.8 mg kg(-1) in Entisols and Inceptisols, respectively. The novel approach of determination of critical limits of B by using polynomial equations was found effective.

We evaluated long-term impact of agro-ecological zones and cropping systems on stock and stability of organic C in soils along depth. Sixty geo-referenced soil samples were collected from Terai (TZ) and New Alluvial (NAZ) agro-ecological zones of Wet Bengal. In each zone, soil samples were drawn at 0-0.3, 0.3-0.6 and 0.6-0.9 m depth from rice-potato-jute (R-P-J), rice-vegetables-vegetables (R-V-V), vegetables-vegetables-vegetables (V-V-V) and rice-rice (R-R) cropping systems. Total organic C (TOC) in soils and its pools viz., easily oxidizable Walkley and Black C (C-WB), very labile (C-VL), labile (C-L), less labile (C-LL), non-labile (C-NL), active (C-AP), and passive (C-PP) were measured separating on the basis of ease of oxidation with chromic acid for computing different indices of soil organic C (SOC). Among the cropping systems, on average, rice-based systems had higher TOC and C-NL than non-rice (V-V-V) one, particularly in NAZ; while non-rice system had a higher per cent allocation of SOC in C-VL. Again, a greater per cent of SOC occurred in C-PP and C-AP under rice-based and non-rice systems, respectively. Anaerobiosis thus facilitated formation of a higher proportion of SOC in recalcitrant pools. Stratification ratios of organic C were higher for soils under NAZ than those under TZ, and also for soils under rice-based systems than those under non-rice one indicating a better soil quality in the former than the latter zone and systems. This was again corroborated with higher values of carbon management index for NAZ than TZ and R-R than V-V-V systems. Further, the recalcitrant indices (RIs) of SOC were higher for soils of TZ than those of NAZ, contrary to the values of lability index (LI). Among the cropping systems, V-V-V had the highest LI values followed by R-V-V > R-P-J = R-R. Along depth, the values of RIs increased, but LI decreased. There was thus an overriding influence of rice and its ecology on the stock and stability of SOC masking the influence of its companion crops in rice-based systems. Therefore, rice-based systems, grown by default in many regions, had a better C economy in soils of this sub-tropical part of the world.

Restoration and improvement of soil quality is the prerequisite for ensuring agricultural productivity and food security in India. Although intensification enhanced food production, it led to a decline in factor productivity, health of environment, and an impairment in soil quality. The declined soil quality is manifested through impaired ecosystem services and also loss in yield and profitability. Soil organic C (SOC) is considered as the panacea for maintaining the soil quality through improved microbial activities, water availability and nutrient use efficiency. The present review emphasizes the need for maintenance of SOC content in Indian soils challenged with high oxidative loss out of high temperature, good moisture and cultivation led soil perturbations. Importance of balanced fertilization through soil test, integrated nutrient management, and adoption of innovative farming practices such as conservation agriculture for enhancement of SOC storage and consequent improvement in soil quality even under intensive cultivation in various agro-climatic regions of the country is emphasized.