Subsequent Wheat Research Articles

Direct and residual effect of boron on growth parameters and yield of rice-wheat grown under the Inceptisol of Varanasi

A pot experiment was conducted in net house of the Department of Soil Science and Agricultural Chemistry, Institute of Agricultural Sciences, Banaras Hindu University, Varanasi, India during kharif 2017 and rabi 2017-18 to evaluate the direct effect boron (B) fertilizers on plant growth parameters of rice and their residual effect on subsequent wheat crop grown in B deficient soil (0.42 mg kg-1). The experiment comprised of 9 B levels i.e., 0, 0.5, 1.0, 1.5, 2.0, 2.5, 3.0, 3.5 and 4.0 kg B ha-1 in soil as borax (B:11%) along with basal dose of nitrogen, phosphorus and potassium as treatments in a completely randomized design (CRD) with three replications. The result showed that among the levels of boron the direct application of 1.5 kg B ha-1 soil along with RDF to rice was most beneficial and brought highest improvement in growth parameters and on succeeding wheat crop the most beneficial and highest yield was in residual B of 3.0 kg B ha-1. The yield increased due to residual effect of B was statistically lower than the direct effect of B. Boron concentration in soils ranged from 0.54 to 0.43 mg kg-1 in rice and 0.29 to 1.25 mg kg-1 in wheat. The plant growth attributes like plant height, Greenness index, and number of tillers along with yield were increased by the direct and residual effect of B levels. The application of boron did not increase grain yield of rice and wheat significantly over RDF. However, application of B @ 2 kg ha-1 or higher doses significantly decreased the rice grain yield. In, wheat, the grain yield was at par in all the treatments. A significant residual effect of B application in rice was noticed even after the harvest of wheat crop particularly at highest doses of application.

Soil water infiltration after oilseed crop introduction into a Pacific Northwest winter wheat–fallow rotation

Rapid water infiltration is important for improving water storage and reducing erosion potential in arid and semiarid areas. Taprooted crops are sometimes credited with improving water infiltration. In a study repeated over three years, we tested whether adding a single brassica crop year to the traditional wheat (<i>Triticum aestivum</i>)–summer fallow rotation would improve water infiltration. We found significantly faster rates of ponded water infiltration in subsequent wheat crops following canola (<i>Brassica napus</i>; 29.68 ± 19.83 mm h^–1 [1.17 ± 0.78 in hr^–1], <i>n</i> = 24) and mustard (<i>Brassica carinata</i>; 25.27 ± 17.32 mm h^–1 [0.99 ± 0.68 in hr^–1], <i>n</i> = 19) as compared to wheat following winter wheat (21.14 ± 15.78 mm h^–1 [0.83 ± 0.62 in hr^–1], <i>n</i> = 24). The greater infiltration rates measured following brassicas compared to wheat were not attributed to root channels due to the lack of visible channels. Crop diversification with oilseeds can increase water infiltration after only a single crop year.

Assessing Effects of Crop History and Soil Amendments on Yields of Subsequent Crops

Three field trials were set up to measure the effect of previous crops or soil amendments on the yields of subsequent crops of cereals under a cool temperate maritime climate in arable crop land in the east of Scotland. Winter wheat and winter barley direct drilled into legume and cereal + legume stubble (pre-crop) gave substantial yield boost compared with other pre-crop cereals, but pre-crop effects of oats were similarly great. Restored rotation after continuous barley gave expected yield enhancement to subsequent winter and spring barley but not to subsequent wheat. Some diseases were reduced on restored rotation crops. Slurry effects on yield were generally small but beneficial and compost effects were greater. However, compost had effects on plant developmental speed and was difficult to compare directly with other treatments. NDRE measurements in the restored rotation and soil amendment trials indicated that yield gains were associated with improved crop health as indicated by leaf chlorophyll content. There were no clear cultivar interactions within crop type with treatments effects in any of these trials.

Tillage and residue management practices affect soil biological indicators in a rice–wheat cropping system in north‐western India

AbstractAgricultural productivity relies on a wide range of ecosystem services provided by the soil biota. Sustainable management practices, such as tillage and residue management, can influence structure and function of the soil microbiota, with direct consequences for the associated ecosystem services. Although there is increasing evidence that different tillage regimes alter the soil biological indices, we only have a limited understanding of their temporal changes in a rice (Oryza sativaL.)–wheat (Triticum aestivumL.) cropping system. We evaluated the effects of combinations of tillage, crop residue management and green manuring on soil biological indicators after 5 years of the practising rice–wheat system (RWS). Four main plot treatments in rice included the following: (a)PTRW0, puddled transplanted rice with no wheat straw retained; (b)PTRW25, puddled transplanted rice with 25% anchored wheat stubbles retained; (c)PTRW0+Sesbania aculeateL. green manure (GM); and (d)PTRW25+GM, puddled transplanted rice with 25% anchored wheat stubbles retained+GM. There were three subplot treatments in the subsequent wheat crop: (a)CTWR0, conventional tillage wheat with rice residue removed; (b)ZTWR0, zero tillage wheat with rice residue removed; and (c)ZTWR100,ZTWwith 100% rice residue retained as mulch. ThePTRW25+GMtreatment, followed byZTWR100, significantly increased soil microbial biomass carbon, basal soil respiration, microbial quotient and mineralization quotient measured during wheat‐growing season. These biological indicators were higher at vigorous vegetative wheat growth stage than at flowering stage and decreased at maturity. The principal component analysis of the assayed variables showed that all the variables significantly contributed to the variability in parameters examined and were more related to maximum tillering stage of wheat growth than to maturity or at sowing of wheat. Three highly effective biological indicators were microbial biomass carbon, microbial quotient and mineralization quotient, which responded significantly to changes in tillage and residue management practices in theRWS. We conclude that crop residues and green manure have significant to improve soil biochemical processes by improving soil organic carbon and soil biological indicators in rice–wheat cropping system.

Combined soil and foliar ZnSO4 application improves wheat grain Zn concentration and Zn fractions in a calcareous soil

AbstractDietary zinc (Zn) deficiency is a common micronutrient deficiency in humans. Zinc fertilization has been proved to be an effective approach to improve grain Zn concentration in wheat and alleviate Zn deficiency in humans. To maximize the potential of Zn fertilization, it is necessary to select appropriate Zn fertilizer forms and application methods. Here, combined soil and foliar application of ZnSO4, rather than Zn‐EDTA, effectively increased grain Zn concentration in winter wheat (Triticum aestivum L. cv. “Xiaoyan 22”) grown in a calcareous soil. However, neither ZnSO4 nor Zn‐EDTA, when applied to the soil or the foliage alone, had any significant effect on grain Zn concentration. The fractions of Zn loosely bound to organic matter, carbonate‐bound Zn and manganese oxide‐bound Zn in the rhizosphere soil changed dynamically over the course of the wheat growth period, with the highest levels found at the jointing stage. The residual ZnSO4 fertilizer had a positive effect on grain Zn concentration in the subsequent wheat crop due to increased storage of phytic acid in wheat grains and high concentrations of Zn loosely bound to organic matter and carbonate‐bound Zn in the soil. In comparison, Zn‐EDTA applied to the soil only increased the exchangeable‐Zn fraction, and had little residual effect on any other Zn fraction. Repeated soil applications of Zn‐EDTA would be effective to improve grain Zn concentration in wheat plants in subsequent years.Highlights Effects of Zn fertilization in a calcareous soil were tested by a 3‐year field experiment. Combined soil and foliar application of ZnSO4 improved grain Zn concentration in wheat. Foliar ZnSO4 or Zn‐EDTA application alone had no significant effects on grain Zn concentration. Soil ZnSO4 application had a long‐term positive effect on grain Zn concentration in the subsequent wheat crop.

Canola Breeding for HUMAN HEALTH

Canola Breeding for HUMAN HEALTH

Wheat yield as a measure of the residual fertility after 20 years of forage cropping systems with different manure management in Northern Italy

After 20 years of application of different manure types, cropping systems and additional nitrogen (N) levels, their residual fertility effects were compared by measuring the yield of a following unfertilised wheat crop (Experiment 1), which was sown on exactly the same plots of the previous long-term trial. All previously applied factors caused significant differences in wheat yield. Wheat yielded more on plots that had received farmyard manure (FMY) compared to those where semi-liquid manure (SLM) was previously applied. Long-term application of a semi-intensive rotation, with three years of annual double cropping of autumnsown Italian ryegrass and spring-sown silage maize followed by three years of mown lucerne (R6), resulted in higher wheat yield than application of just the annual double cropping of Italian ryegrass and silage maize (R1). Application of further mineral N fertilisation to previous cropping systems caused higher yield of the subsequent wheat crop. The difference in wheat yield between the R6 and R1 systems was greater with SLM (+28%) than FYM application (+11%) resulting in a significant manure × system interaction. A companion experiment (Experiment 2) was carried out to compute the nitrogen agronomic efficiency (NAE) from the yield of wheat plots that were sown after ploughing a nearby 20- year unfertilised grassland and received four levels of mineral N fertilisation. NAE was further used to empirically estimate the productive advantage (PA) conferred by previous manure-systemmineral nitrogen combinations in the long-term trial. PA was measured as equivalent kg of mineral N to be applied to wheat to achieve the yield level recorded after any previous combination. The estimated PA values were much higher when wheat followed FYM compared to SLM application, and when it followed R6 compared to R1 system. The SLM-R1 combination had negative PA values, indicating a productive disadvantage on wheat of this preceding combination. The enhancement of residual soil fertility by long-term application of FYM compared to SLM could be attributed to greater nutrient provision during the years by FYM than by SLM. However, further fertility advantages of FYM are discussed. Despite lower nutrient supply by organic fertilisers in R6 than in R1 system, the former had higher residual fertility. The presence of lucerne in the R6 rotation likely enriched the soil in nitrogen and increased its availability for following cropping. Possible benefits of the legume on the soil suppressiveness might have been a further asset of the R6 system.

Soil Microbial Biomass and Fungi Reduced With Canola Introduced Into Long-Term Monoculture Wheat Rotations.

With increasing canola (Brassica napus L.) acreage in the Inland Pacific Northwest of the USA, we investigated the effect of this relatively new rotational crop on soil microbial communities and the performance of subsequent wheat (Triticum aestivum L.) crops. In a 6-year on-farm canola-wheat rotation study conducted near Davenport, WA, grain yields of spring wheat (SW) following winter canola (WC) were reduced an average of 17% compared to SW yields following winter wheat (WW). Using soil samples collected and analyzed every year from that study, the objective of this research was to determine the differences and similarities in the soil microbial communities associated with WC and WW, and if those differences were associated with SW yield response. Microbial biomass and community composition were determined using phospholipid fatty acid analysis (PLFA). The WC-associated microbial community contained significantly less fungi, mycorrhizae, and total microbial biomass than WW. Additionally, reduced fungal and mycorrhizal abundance in SW following WC suggests that the canola rotation effect can persist. A biocidal secondary metabolite of canola, isothiocyanate, may be a potential mechanism mediating the decline in soil microbial biomass. These results demonstrate the relationship between soil microbial community composition and crop productivity. Our data suggest that WC can have significant effects on soil microbial communities that ultimately drive microbially mediated soil processes.

15N Fertilizer recovery in different tillage–straw systems on a Vertisol in north‐west Mexico

AbstractTillage and residue retention affect nitrogen (N) dynamics and nutrient losses and therefore nitrogen use efficiency (NUE) and crop fertilizer use, however, there is little information about residual fertilizer effects on the subsequent crop. Micro‐plots with 15N‐labelled urea were established in 2014/2015 on a long‐term experiment on a Vertisol in north‐west Mexico. N fertilizer recovery (NFR) and the effects of residual fertilizer N for summer maize (Zea mays L.) and the subsequent wheat (Triticum durum L.) crop were studied in three tillage–straw management practices (CTB: conventionally tilled beds; PB‐straw: permanent raised beds with residue retention; PB‐burn: permanent raised beds with residue burning). Fertilizer 15N recovery rates for maize grain across all treatments were low with an average of 11%, but after wheat harvest total recovered 15N (15N in maize and wheat straw and grain, residual soil 15N) was over 50% for the PB‐burn treatment. NFR was lowest in CTB after two cropping cycles (32%). Unaccounted N from applied fertilizer for the maize crop averaged 120 kg 15N ha−1 after wheat harvest. However, more than 20% of labelled 15N was found in the 0–90 cm soil profile in both PB treatments after wheat harvest, which highlights the need for long‐term studies and continuous monitoring of the soil nutrient status to avoid over‐application of mineral N fertilizer.

Effect of elevated temperature and carbon dioxide on wheat (Triticum aestivum) productivity with and without weed interaction

Wheat (Triticum aestivum L.) crop is one of the most valuable crops, and further boost in wheat yields is essential to meet the food demand of the emerging world population. It is therefore necessary to know the influence of future climate change on wheat yields. Present investigation was conducted in temperature gradient tunnel (TGTs) to evaluate the effects of elevated temperature, CO2 concentration,weed and their interactions on grain, biological yield and other yield attributes (number of spikes/m2, number of spikelets/spike, number of grains/spike and 1000-grain weight, harvest index) of wheat. Wheat crop was grown in TGT at three different temperature levels, i.e. T1 ambient, T2 ambient+1.5°C, T3 ambient+3°C and two levels of carbon dioxide, i.e. ambient (ACO2) 400 ppm and elevated (ECO2) 550±50 ppm with and without weed interaction.The study revealed that yield and yield attributes of subsequent wheat crop increased due to ECO2. Mean individual effect of ECO2 increased grain yield of wheat by 14% and biological yield by 12% compared to ACO2. On the contrary, the yield was decreased with elevated temperature where a decrease in the grain yield from ˗12% to ˗20% and biological yield from ˗11% to ˗18% was observed at 1.5°C and 3°C, respectively. Similarly the interaction of weeds in wheat crop, reduced the grain yield by 8% and biological yield of wheat by 6%, irrespective of CO2 and temperature levels.The statistical analysis (P&lt;0.05) revealed significant effect of the interactions (C×T, C×W, W×T, and C×T×W) on yield. Overall results the study proposal to adapt an effective weeds management strategy to controlled conditions of yield of wheat crop under the controlled conditions of CO2 and temperature.

Temporal changes in biochemical indicators of soil quality in response to tillage, crop residue and green manure management in a rice-wheat system

Abstract Soil quality degradation in the last four decades is threatening the sustainability of puddled transplanted rice (Oryza sativa L.) – wheat (Triticum aestivum L.) (RW) system in north-western region of India. Hence comprehensive information on the influence of soil and crop management practices in intensive and nutrient exhausting RW system on soil quality is urgently needed. The present study evaluated the effects of crop residues, green manure and tillage on the changes in soil biochemical properties at different growth stages of wheat after five cycles of RW system. Four main plot treatments in rice included combinations of wheat straw and Sesbania green manure management: (1) PTRWS0, puddled transplanted rice (PTR) with no wheat straw (2) PTRWS25, puddled transplanted rice with 25% anchored wheat stubbles retained (3) PTRWS0 plus green manure (GM), and (4) PTRWS25 plus GM. Three sub-plots treatments in subsequent wheat included (1) CTWRS0, conventional tillage wheat without rice straw (2) ZTWRS0, zero tillage wheat without rice straw and (3) ZTWRS100, ZTW with 100% rice straw retained as surface mulch. The results showed that PTRWS25 plus GM and ZTWRS100 increased significantly all the soil biochemical properties (enzyme activities and glomalin related soil protein concentration) except phenol oxidase and peroxidase activities. The activities of dehydrogenase, β-glucosidase and concentration of easily extractable glomalin and total carbohydrate carbon under ZTWRS100 were 36.8, 24.6, 25.9 and 23.3% higher than CTWRS0. Application of GM and wheat straw retention in previous rice significantly increased grain yield of subsequent wheat crop by 26.5%. The majority of the increases in biochemical properties were higher at vegetative growth (at 40–45 days after sowing) and flowering (at 80–85 days after sowing) stages compared to the initial and at maturity. Principal component analysis identified β-glucosidase, cellulase and phenol oxidase activities as the most sensitive and reliable indicators for assessing soil quality for conservation agriculture based RW system.

Effect of long-term nutrient management practices on soil micronutrient concentrations and uptake under a rice–wheat cropping system

AbstractA field experiment was conducted to study the long-term effects of nutrient management practices on micronutrient concentrations in soil and their uptake by crops under a long-term rice–wheat cropping system. The treatments comprised different combinations of N, P, K, Zn and farm yard manure (FYM), used as nutrient management practices. After 25 years of continuous cropping, the higher grain yields and uptake of iron (Fe), manganese (Mn), copper (Cu) and zinc (Zn) were obtained when FYM was applied along with mineral sources of nitrogen, phosphorus and potassium (NPK) when compared to mineral sources of NPK alone. The residual effect of FYM, applied to rice, on the yield of subsequent wheat was significant. The application of mineral NPK with FYM recorded higher diethylene triamine penta acetic acid extracted (DTPA)-Fe, Mn and Cu concentrations in the soil compared to any other treatment. The plots with Zn application showed higher DTPA-Zn concentration in the soil compared to any other treatments. The available Fe, Mn and Cu in the soil were higher than their critical limits and the soil was low in Zn where inorganic fertilizers were applied alone (without Zn). Integrated application of mineral NPK and FYM to the rice crop and mineral NPK to wheat was found to be the best nutrient management practice in producing higher yields of rice and wheat and improve long-term soil micronutrient concentrations.

Estimates on nitrogen uptake in the subsequent wheat by above-ground and root residue and rhizodeposition of using peanut labeled with 15N isotope on the North China Plain

Leguminous crops play a vital role in enhancing crop yield and improving soil fertility. Therefore, it can be used as an organic N source for improving soil fertility. The purpose of this study was to (i) quantify the amounts of N derived from rhizodeposition, root and above-ground biomass of peanut residue in comparison with wheat and (ii) estimate the effect of the residual N on the wheat-growing season in the subsequent year. The plants of peanut and wheat were stem fed with 15N urea using the cotton-wick method at the Wuqiao Station of China Agricultural University in 2014. The experiment consisted of four residue-returning strategies in a randomized complete-block design: (i) no return of crop residue (CR0); (ii) return of above-ground biomass of peanut crop (CR1); (iii) return of peanut root biomass (CR2); and (iv) return of all residue of the whole peanut plant (CR3). The 31.5 and 21% of the labeled 15N isotope were accumulated in the above-ground tissues (leaves and stems) of peanuts and wheat, respectively. N rhizodeposition of peanuts and wheat accounted for 14.91 and 3.61% of the BG15N, respectively. The 15N from the below-ground 15N-labeled of peanuts were supplied 11.3, 5.9, 13.5, and 6.1% of in the CR0, CR1, CR2, and CR3 treatments, respectively. Peanut straw contributes a significant proportion of N to the soil through the decomposition of plant residues and N rhizodeposition. With the current production level on the NCP, it is estimated that peanut straw can potentially replace 104 500 tons of synthetic N fertilizer per year. The inclusion of peanut in rotation with cereal can significantly reduce the use of N fertilizer and enhance the system sustainability.

In Situ Maize Residue Mulch Improves the Water Use Efficiency and Yield of the Subsequent Wheat under a Strip Inter‐Cropping System

Core Ideas Irrigation and straw mulch increased yields and WUE, compared with non‐mulch, especially in dry years. Enhanced grain yield was largely influenced by changes in WUE, soil water, SPAD and dry matter. Residue retention in the fallow period conserves soil moisture, delays senescence and improves wheat production. Seasonal drought is a limiting factor for wheat (Triticum aestivum L.) production in the southwest hill regions of China. During a 4‐yr field experiment conducted in Jianyang, Sichuan Basin, we evaluated the effects of production‐system residue retention on water use, physiological characteristics, and grain yield of winter wheat grown in a relay strip cropping system. Four treatments were used: whole‐period without mulch or irrigation (NM), no mulch plus irrigation at sowing and jointing (NMI); whole‐period mulch without irrigation (WM); and fallow‐period mulch without irrigation (FM). The results were that irrigation and straw mulch increased yields by 0 to ∼42% and water use efficiency (WUE) by 0 to ∼30%, compared with NM, especially in dry years. Improvement in grain yield under residue retention was attributed to increased spike number. Residue retention significantly improved the following crop parameters; tiller numbers, aboveground dry mass accumulation, soil moisture, root length density, and root surface area at critical growth stages, as well as inhibiting leaf chlorophyll loss after anthesis. The FM achieved greater performance on the above parameters than WM. Enhanced grain yield was largely influenced by changes in WUE, gravimetric soil water, SPAD value and dry matter accumulation. In conclusion, residue retention over the fallow period is instrumental in conserving soil moisture, delaying leaf senescence and improving wheat production. This treatment was also the most convenient for farmers.

Rice–wheat productivity and profitability with residue, tillage and green manure management

The rice–wheat system (RWS) practiced in northwestern parts of the Indo-Gangetic plains of India is highly productive, but conventional practices are resource (water, labour and energy) and cost intensive. A 4-year field study evaluated the effects of green manure (GM), crop residue and tillage on crop yields, economic profitability and soil fertility in a RWS. Four main plot treatments in rice included combinations of wheat stubble and Sesbania aculeata GM management: (1) puddled transplanted rice (PTR) with no wheat stubble, (2) PTR with 25% wheat stubbles (15–20 cm high) retained, (3) PTR with no wheat stubble plus GM, and (4) PTR with wheat stubble splus GM. Three sub-plots treatments in subsequent wheat included (1) conventional till wheat with rice straw removed (CTWR0), (2) zero till wheat with rice straw removed (ZTWR0) and (3) zero till wheat with 100% rice straw retained as surface mulch (ZTWR100). The results showed that main rice yield was significantly higher (8.0%) with 50% less fertilizer N application in GM compared with conventional PTR with no GM. Rice treatments did not affect the grain yield of subsequent wheat. ZTWR100 produced significantly higher mean wheat grain yield by 7.3% and 17.5% compared with CTWR0 and ZTWR0, respectively. System productivity was 11.5% higher in PTR with wheat stubble + GM followed by ZTWR100 compared with the conventional RWS and resulted in Rs 24,075 ha−1 more net returns. Significant increases in soil organic carbon, available P and available K contents were recorded in ZTWR100 over CTWR0. Recycling rice and wheat stubble in the field in RWS is also environment friendly as it avoids ill effects of straw burning.

Residual effect of biochar and summer legumes on soil physical properties and wheat growth

Abstract Biochar, a carbon-rich solid material and legumes having numerous benefits to the soil-plant system gaining a keen interest as an innovative sustainable approach among the agriculture research community in many parts of the world especially in developing countries in order to enhance soil quality and ensure food security. Thus, with the same approach, we have carried out a field experiment to examine the residual effect of biochar application and summer legumes on soil physical properties and subsequent wheat crop growth at the Research Farm, The University of Agriculture Peshawar during winter 2016-2017. An experiment was designed in two-factor factorial randomized complete block design with three replications in summer 2016 in which three different summer legumes i.e. mungbean, sesbania, and cowpea were grown in the summer for the purpose of grain, green manuring and fodder, a fallow was also included with the purpose of control. Biochar was applied at the rate of 0, 5 and 10 tons ha-1. After the harvesting of summer legumes, sesbania biomass was completely incorporated into the soil while the biomass of other two legumes were removed. The experiment on subsequent wheat was on the same field layout of summer legumes. Both the treatments i.e. previously applied biochar especially 10 tons ha-1 and preceding summer legumes especially sesbania as well as their interaction showed a significant effect on the selected soil physical properties. Similarly, the response of wheat growth was also significant to both treatments but their interaction was non-significant. Thus, it was concluded that both the treatments had a significant effect on the soil physical properties and growth of wheat and should be included in the cropping system. Keywords: Biochar; soil physical properties; summer legumes; wheat growth http://dx.doi.org/10.19045/bspab.2018.700159

Significance of manganese fertilization in wheat-based cropping systems of Indo-Gangetic Plain (IGP)

Manganese (Mn) is an essential micronutrient, having critical role in plant nutrition. The Mn is component of several enzymes involved in photosynthesis and other physiological processes. The intensive cultivation of rice-wheat (RW) followed since long times, along with induction of rice in non-rice growing areas, especially in north-western Indo Gangetic Plain (NW-IGP) had led to emergence of Mn deficiency, particularly in wheat crops in RW rotation. Higher leaching losses of soil Mn under submerged rice induces Mn deficiency in the subsequent wheat crops. This paper critically assesses the literature on role of Mn on crop growth, distribution of soil Mn and its dynamics, effect of different soil characteristics on soil Mn availability under different cropping systems prevalent in IGP. Soil ionic composition, moisture status, organic matter status, soil pH, cation exchange capacity are some of the soil parameters dictating Mn dynamics in soil. Higher availability of soil Mn was reported under acidic condition, which decreasedwith increase in soil pH. Literature suggests positive effects of nitrate and phosphates on soil Mn dynamics and crop yields, whereas bicarbonate and chloride application have negative effects. Plant available Mn or DTPA-Mn varied under different cropping systems showing lower availability under RW system. Fractionation studies showed that labile pools of Mn contribute very less towards total soil Mn, leaving large proportion of soil Mn non-labile in nature, thus unavailable for plant uptake. The release of Mn from soil adsorption sites varied under different cropping systems, modifying Mn supply capacity of soil. Maximum release of Mn was found under frequently irrigated sugarcanesugarcanecropping system. Such information are essentially required for developing efficient Mn fertilization scheduling to improve the yield and quality of crops in IGPs.

Changes in soil biochemical indicators at different wheat growth stages under conservation-based sustainable intensification of rice-wheat system

Soil microbes play critical roles in soil biogeochemistry, soil biological health and crop productivity. The current study evaluated the effects of tillage and residue management on changes in soil biochemical indicators at different growth stages of wheat after 5 years of rice-wheat system. Nine treatment combinations of tillage, crop establishment and crop residue management included three main plot treatments applied to rice: (1) conventional till direct dry seeded rice (CTDSR), (2) zero till direct dry seeded rice (ZTDSR), and (3) conventional puddled manual transplanted rice (CTPTR) and three subplot treatments in subsequent wheat: (1) conventional tillage with rice residue removed (CTW-R), (2) zero tillage with rice residue removed (ZTW-R) and (3) zero tillage with rice residue retained as surface mulch (ZTW+R). Irrespective of rice treatments, ZTW+R treatment had higher soil biochemical indicators compared with ZTW-R and CTW-R at all the growth stages of wheat. Generally, all the biochemical indicators were the highest at the flowering stage of wheat. Residual effect of rice treatments was also significant on biochemical quotients in wheat, which were the highest under ZTDSR followed by CTDSR and CTPTR. The present study provided three sensitive and reliable biochemical indicators (microbial biomass, basal soil respiration and microbial quotient) which respond rapidly to change in tillage and residue management practices in RWS of South Asia.

Wheat Grain Enrichment with Zinc Through Using Zinc Fertiliser and Preceding Plant Residues Incorporation

Abstract Micronutrients and particularly zinc (Zn) deficiency affects crops productivity and human health, therefore improving Zn concentration within plant tissues might be regarded as an aim of sustainable agriculture. In this respect, a field experiment was carried out to examine the potential influence of preceding crop residues including bean and wheat incorporation into the soil as a way to improve zinc accumulation within subsequent wheat (Triticum aestivum L.) grain. The experiment was initiated at autumn 2014 and in the first year, a piece of farm land in Dehaghan-Isfahan-Iran was divided into two equal parts devoted to wheat and bean cultivation. At the end of the harvest season, aboveground plant residues were incorporated to 0-30 cm layer of soil. In the next year, the entire farm devoted to wheat production. The applied treatments included: control, zinc sulfate (60 kg/ha), wheat residues, bean (Phaseolus vulgaris L.) residues, wheat residues + zinc sulfate and bean residue + zinc sulfate. The results of analysis of variance showed the highly significant differences between treatments in terms of grain zinc, protein, phytic acid to zinc molar ratio (PA/Zn), quantitative yield and soil electrical conductivity (EC). Soil pH and organic carbon (OC) were not affected by treatments while soil EC significantly increased by using plant residues. The highest grain yield (3.8 t/ha), grain protein (10.3 mg/kg) and zinc concentrations (36 mg/kg) were obtained by using bean residues plus ZnSO4 while the lowest quantities were related to control treatment. The treatments had no significant impact on grain acid phytic concentration but phytic acid / zinc molar ratio was affected by treatments and the lowest ratio (which is a positive attribute) was measured from plots containing bean residues plus ZnSO4 while the highest occurred in control plots.

Pea and Barley Forage as Fallow Replacement for Dryland Wheat Production

Core Ideas Forage yields from pea, especially winter pea, were competitive with hay barley yields.Crude protein yield from pea forage was 40 to 110% greater than barley.Crop harvest at the bloom stage used the least soil water and nitrogen.Wheat yield following pea averaged 82 to 88% of that on chemical fallow. There is a growing interest in the use of annual forages in rotation with wheat (Triticum aestivum L.). The objectives of this study were to: (i) compare forage yield and quality of spring and winter pea (Pisum sativum L.), barley (Hordeum vulgare L.), and a pea–barley mixture harvested at flowering (early), pod (late), or grown to maturity; and (ii) compare the cropping‐sequence effects of these cropping treatments for three N fertilizer rates, subsequent wheat yield, and grain quality relative to chemical fallow. This study was conducted at Amsterdam, MT, from 2003 to 2006. Pea forage yield at the pod stage was 1.2 Mg ha−1 (30%) and 3.7 Mg ha−1 (60%) greater than at the flower stage for spring and winter pea, respectively. At the same harvest times, spring barley forage averaged 1.8 Mg ha−1 (32%) greater either as a sole species or when mixed with spring pea. Forage quality of pea forage was high regardless of harvest timing. Protein yield for spring and winter pea forage averaged 0.28 (60%) and 0.38 Mg ha−1 (81%) greater than the barley forage treatments across harvest times and years. Significant differences in stored soil water (19 mm) and soil nitrate N (10 kg N ha−1) were found between flowering and pod forage harvest timing in pea, but these differences only nominally affected subsequent wheat yield or quality. Wheat following pea averaged approximately 85% of the yield on chemical fallow. Among the cropping treatments, the greatest wheat yield and protein occurred following winter pea harvested at the flower stage.