Impact of Safe Rock® Minerals, Mineral Fertilizers, and Manure on the Quantity and Quality of the Wheat Yield in the Rice–Wheat Cropping System

Rice–wheat (RW) rotation is the largest agriculture production system in South Asia with a multifaceted role in maintaining the livelihood of people. The customary practices and indiscriminate use of synthetic fertilizers have culminated in the decline of its productivity and profitability during the past two decades, thus affecting the sustainability of wheat. Safe Rock® Minerals (SRM) is a multi-nutrient rich natural rock mineral with great potential to manage soil degradation, reducing the input of fertilizers, improving soil fertility, and plant health. Thus, a field trial was conducted at the research farm of ICAR—Indian Agricultural Research Institute, New Delhi from 2016 to 2018 to evaluate the impact of Safe Rock® Minerals (SRM) on biometric parameters, productivity, quality, and nutrient uptake by conventional wheat and System of Wheat Intensification (SWI) in the wheat–rice cropping system. The results indicate that SWI performed better in terms of growth, yield, and quality parameters than conventional wheat. Among nutrient management practices; the highest growth, yield, and yield attributes of wheat were achieved with the use of SRM application 250 kg ha−1 + 100% Recommended Dose of Fertilizer (RDF). SRM application also increased grain protein content significantly. In conclusion, the integrated use of SRM with organic manures can serve as an eco-friendly approach for sustainable wheat production.

Influence of weather and nutrients (FYM, N and P) on RGR, LAD, NAR and CGR to determine the productivity of maize, wheat and green gram in a cropping system

In a field experiment, conducted during 2018-19 and 2019-20 at the Research Farm, Indian Agricultural Research Institute, New Delhi, factorial combinations of two levels of FYM (0, 10 Mg ha−1) applied to maize; four levels of nitrogen (0, 60, 120, 180 kg N ha-1) and three levels of phosphorus (0, 30, 60 kg P2O5 ha−1) applied to both maize and wheat and subsequent residual effects on green gram were compared. The RGR was at peak in maize at 29oC and in wheat at 12-13 oC. Integral of LAD and incidental solar radiation has significantly improved CGR. The LAD and CGR also shown significant relationship with grain/ seed yield in all three crops. Slightly higher NAR in combination with LAD and SRD can significantly contribute to overall performance of crops. Results indicated that variation in yield across years due to weather fluctuations, irrespective of treatments, was about 16.7 per cent in maize (kharif), 7.93 per cent in wheat (rabi) and 16.8 per cent in green gram (summer).

Gene Action Governing the Inheritance of Stomatal Conductance in Four Wheat Crosses Under High Temperature Stress Condition

The knowledge pertaining to gene action and interactions involved in the inheritance of a character in different generations is crucial for determining the breeding strategies in crop improvement program. In the present study, the gene action of stomatal conductance was determined in four wheat populations under high elevated temperatures coupled with late sowing at experimental farm, ICAR-Indian Agricultural Research Institute, New Delhi, India. Steady-state SC-1 leaf porometer was used to record stomatal conductance on adaxial and abaxial leaf surface at late boot (Z 49–50), early milk (Z 73), and late milk (Z 77) growth stages. Evidence for nuclear genetic control of stomatal conductance was strong, with large and repeatable genetic difference observed for parents and progeny across all the four crosses. Mean stomatal conductance for genotypes, GW 322 and GW 366, was consistently low at late boot, early milk, and late milk under timely sown, late sown, and very late sown condition, whereas the converse was true for the high-conducting parents, KAUZ/AA//KAUZ and RAC 875. Additive and additive x additive epistatic effects were large and reasonably consistent at three stages and in all crosses. Detection of epistasis and evidence of transgressive segregation suggested that variation for stomatal conductance was under oligo or polygenic control. Thus, it is conceivable that independent alleles at two or more loci could be pyramided into a single family for increased or decreased stomatal conductance. Additive-based gene action also facilitates with simple selection at early generation to improve stomatal conductance in expected direction. This is the first report on estimates of gene action for stomatal conductance of flag leaf under heat stress condition during reproductive and grain filling stage.

Radiation dimming induced modifications in radiation utilization of wheat (Triticumaestivum) crop

Global dimming has many environmental and climatic implications. India has also experienced a steady and continuous radiation dimming since 1960s due to increasing load of dust and aerosol in the atmosphere. Radiation interception, temperature, humidity and wind profile are altered under reduced light condition which are determining factor for crop phenology, leaf area index, biomass production, grain yield and radiation use efficiency of crops.In this experiment, three wheat cultivars (HD 2967, WR 544 and PBW 502) were grown under five solar radiation treatments i.e. R1 (no shading), R2 (20% shading), R3 (35% shading), R4 (50% shading) and R5 (75% shading) during rabi season of 2014-15 and 2015-16 at research farm of ICAR-Indian Agricultural Research Institute (ICAR-IARI), New Delhi to study the effect of radiation dimming on performance of selected wheat cultivars.In both the years the canopy temperature of wheat from crop vegetative stage to maturity was decreased with increase of shading level. The effect of reduced solar radiation significantly decreased the biomass production and yield.The radiation use efficiency (RUE) for biomass was increased due to shading treatments whereas the RUE for yield decreased with radiation reduction.The RUE for yield was the highest for no shading treatment (0.85 and 0.75 g MJ-1 in 2014-15 and 2015-16, respectively). Among the cultivars, the radiation use efficiency for biomass as well as yield was the highest in HD 2967 followed by WR 544 and PBW 502,respectively.

Modeling impacts of climate change on spring wheat in northern India

This study attempts to quantitatively understand the impact of changes in meteorological drivers due to climate change on spring wheat in northern India using numerical experiments with the Simple and Universal CRop growth Simulator (SUCROS) model.The model was calibrated and evaluated for spring wheat cultivar HD2967 using observed crop and meteorological data from a field site at the Indian Agricultural Research Institute, New Delhi. Sensitivity studies were performed with the SUCROS model by incrementally changing the meteorological drivers to understand the underlying processes through which each meteorological driver affects spring wheat crop growth. The effect of climate change on spring wheat growth was estimated by conducting numerical experiments where the SUCROS model was driven with bias-corrected projections of future climate from six climate models for two scenarios for mid and end century. Results show that competitive/synergistic interactions between meteorological drivers lead to a slight increase in growth at the beginning of the growing season, and a strong decrease of about 50 per cent during the later stage. Apart from improving our understanding of crop growth processes, this study has also policy implications for agriculture and food security in the context of climate change.

A new bamboo-feeding species, Mohunia manohari sp. nov., (Hemiptera: Cicadellidae: Deltocephalinae) and first record of the genus from India

A new record for the leafhopper genus Mohunia Distant from India is provided with description of Mohunia manohari sp. nov. (Arunachal Pradesh: Basar). Type material is deposited in the National Pusa Collection, Division of Entomology, Indian Agricultural Research Institute (IARI), New Delhi, India. Illustrations habitus and male genitalia of healthy and parasitized males are given along with an annotated checklist to species of the genus.

Emitter Clogging and Hydraulic Performance of Drip System under Different Water Qualities and Placement Techniques

The present study was conducted at the Indian Agricultural Research Institute, New Delhi, India, to evaluate the effect of sand-disc filters, pressure compensating (bioline) and non-pressure compensating (inline) emitters, and surface and subsurface placement of laterals on emitter clogging using wastewater and groundwater for irrigation. Results of this study revealed that besides water quality, the type of emitter, placement of laterals, and emitter position on laterals affected emitter's clogging. The major cause of clogging was associated with the precipitated substance accumulated at the emitter inlet concurrently close the micro-pore channels of the emitter, consequently reduce the emitter discharge. The major substances that took part in the clogging of emitter were EC, pH, HCO3, Turbidity, total solid, Escherichia coli (E. coli), and total coliform. It was observed that these substances (HCO3, Turbidity, total solid, E. coli, and total coliform) of groundwater and wastewater were categorized with a medium risk of clogging except for magnesium (low risk of clogging). Pressure compensating drip emitter showed better performance against clogging as compared to non-pressure compensating drip emitter. Sub-surface placement of drip emitter was more prone to clogging under both wastewater and groundwater. It was observed a significant (p ≤ 0.05) effect of lateral placement, emitter types, and the interaction between these factors on emitter's clogging under both types of water. Emitter flow rate decreased with the increasing time of operation of the drip systems at normal operating pressure, because of clogging of emitters. By flushing operation, it was observed a 3 to 5% higher flow rate in inline drip emitter than bioline (1-2%). The R2 value, which precisely describes the head-discharge relationship, was high (0.99) in most of the bioline treatments. This study also observed and recommended that pressure compensating emitter would be the most appropriate technique to reduce the clogging while using wastewater for irrigation. Flushing effectively controlled the emitter's clogging thus improved the emitter's water discharge rate.

Moths (Insecta: Lepidoptera) of Delhi, India: An illustrated checklist based on museum specimens and surveys

There have been several recent checklists, books and publications about Indian moths; however, much of this work has focused on biodiversity hotspots such as North-east India, Western Ghats and Western Himalayas. There is a lack of published literature on urban centres in India, despite the increased need to monitor insects at sites with high levels of human disturbance. In this study, we examine the moths of Delhi, the national capital region of India, one of the fastest growing mega-metropolitan cities. We present a comprehensive checklist of 338 moths species using 8 years of light trapping data (2012-2020) and examining about 2000 specimens from historical collections at the National Pusa Collection of ICAR-Indian Agricultural Research Institute, New Delhi (NPC-IARI) spanning over 100 years (1907-2020). The checklist comprises moths from 32 families spanning 14 superfamilies with Noctuoidea (48.5%) and Pyraloidea (20.4%) being the the two most dominant superfamilies. We provide links to images of live individuals and pinned specimens for all moths and provide detailed distribution records and an updated taxonomic treatment. This is the first comprehensive annotated checklist of the moths of Delhi. The present study adds 234 species to the biodiversity of moths from Delhi that were not reported previously, along with illustrations for 195 species.

Temperature influence on leafhopper population and its potential distribution in predicting spread of chickpea stunt disease in India

Aim: To study the influence of temperature on leafhopper population for predicting potential distribution of chickpea stunt disease. Methodology: Leaf hopper population was sampled at weekly intervals from chickpea experimental plots at Indian Agricultural Research Institute, New Delhi, during Dec-May 2018-2019 and 2019-2020 by using yellow sticky trap. Effect of temperature on leafhopper population was fitted to a non-linear beta model and Briere model by utilizing cardinal temperature for leafhopper growth and reproduction. Daily minimum and maximum temperature data were collected from 146 geo referenced meteorological stations of important chickpea growing states of India. The cumulative temperature indices (MTI) as a measure of monthly leafhopper population was plotted using ArcGis10.0 software. Results: Temperature index estimated as a measure of leafhopper population based on the beta model potential leafhopper population distribution was predicted. Spatio-temporal pattern of vector population indicated that the entire country is favourable for leafhopper growth round the year, except the Northern parts of India during December to February. Interpretation: Since leafhoppers are the natural vectors of virus and phytoplasma pathogens associated with chickpea stunt disease, beta model based prediction of environmental suitability indicates leafhopper as the causative agent for the natural spread of disease in larger geographical area. Spatio-temporal distribution pattern would be useful in predicting the disease spread in different chickpea growing areas for evolving efficient management strategies.

New record of the genus Baseprocessa (Hemiptera: Cicadellidae: Coelidiinae) from India with description of a new species

The coelidiinae leafhopper genus Baseprocessa Fan & Li is newly recorded from India based on the description of B. patkaensis Meshram sp. nov. and a proposed new combination, B. serratispatulata (Viraktamath & Meshram) comb. nov. Materials are deposited in the National Pusa Collection, Division of Entomology, ICAR-Indian Agricultural Research Institute (IARI), New Delhi, India. Photographic illustrations, checklist and key to species of this genus along with a distribution map are also provided.