Indian Agricultural Research Institute Research Articles

Performance of basmati rice (Oryza sativa) under variable irrigation and nitrogen management

A field experiment was conducted during the rainy seasons (kharif) of 2021 and 2022 at research farm of ICAR- Indian Agricultural Research Institute, New Delhi to study the effect of irrigation regimes and integrated use of prilled urea and nano-urea as a source of N, on productivity and profitability of basmati rice (Oryza sativa L.). The experiment was conducted in a three-time replicated split-plot design (SPD) comprised of 3 irrigation regimes, viz. irrigation at 1, 3 and 6 days after disappearance of surface water (DADSW) assigned to main-plots and 4 N-management variants including; 100% RDN (recommended dose of N, 120 kg/ha); 75% RDN + 4% nano-urea (NU) 2 sprays (75% RDN + 2 NU); 50% RDN + 2 NU; and no-N (control) in sub-plots. Irrigating basmati rice 1 DADSW exhibited the highest panicle weight (2.67–3.09 g) and number of grains/panicle (115.9, 109.8), across the years, respectively that were significantly higher than 3 and 6 DADSW. The most delayed irrigation at 6 DADSW caused significant reduction in grain yield, the magnitude of reduction was 13–19% over irrigation at 3 DADSW and substantially by 23–28% over 1 DADSW. Fertilizing rice crop with 100% RDN and 75% RDN + 2 NU resulted in statistically similar yield attributes and grain yield; however, both were, significantly superior to 50% RDN + 2 NU and no-N. Net returns, benefit cost (B:C) ratio and monetary efficiency were significantly higher when crop was irrigated 1 DADSW than 3 and 6 DADSW. The N-management options followed the trend as RDN>75% RDN + 2 NU ˃50% RDN > no-N for all studied economic parameters.

Comparative Assessment of Solar Refrigerated and Evaporative Cooled (SREC) Structure for On-Farm Storage of Tomatoes

Tomato is an important horticultural crop that is grown worldwide. However tomato is a perishable fruit that needs storage facilities to retard the ripening after harvest, to increase shelf life. Solar refrigerated and evaporative cooled (SREC) structure has developed at the Indian Agricultural Research Institute (IARI) in New Delhi, is an on-farm, off-grid, cold storage option for perishable horticultural produce. SREC storage structure uses an evaporative cooling with solar refrigeration system that provides small holder farmers affordable access to cold storage facility without electrical connection to keep harvested farm produce cool and fresh in farmer’s field. Therefore study of comparative assessment of SREC structure for on-farm storage of tomatoes was conducted. Experiments were conducted to determine and compare interaction of operational parameters temperature and relative humidity and crop parameters weight loss, color change, firmness of tomatoes stored in four storage conditions SREC, EC (evaporative cooled), UL (uncooled laboratory), and REF (refrigerator). The temperature in SREC varied between 4 and 16 °C with relative humidity of 85–100% while UL ambient condition temperature varied between 10 and 35°C. Storage conditions affected the weight loss, color change, firmness of tomato significantly (p<0.05). Overall, the postharvest quality retention was better in SREC and REF as compared to EC and ambient condition.

Morphological characterization of newly developed orangelo (Citrus spp.) hybrids

Present study was carried out during 2021–23 (Ambe and Mrig bahar season) at the research farm of ICAR- Indian Agricultural Research Institute, New Delhi to analyse the morphological diversity of 24 orangelo (Citrus spp.) hybrids and their 4 parents based on 17 quantitative traits such as leaves, flowers, fruits and seed characters. Cluster analysis based on 17 morphological traits divided 28 genotypes of citrus into two main groups. A higher range of variation with average Euclidean distance coefficients ranging from 0.02–0.26 was observed between groups as well as clusters, thereby indicating that genotypes within and among clusters were highly diverse. The PCA for morphological quantitative traits showed that five components leaf lamina length (LLL); leaf lamina width (LLW); LLL: LLW; leaf lamina thickness and pedicel length, of the 17 principal component axis had Eigen-values>1 and all together accounted for over 77.76% of the total variability. Analysing the genetic relationships among the hybrids yielded important insights for potential use in future breeding programmes as valuable sources of desirable traits.

Evaluation of packaging materials for enhancing the storage life of marigold flowers (Tagetes erecta)

Among the various loose flower crops, marigold (Tagetes erecta L.) holds a prominent place among commercial crops. Its vibrant blooms are in high demand, but flowers are perishable, rendering them susceptible to significant post-harvest losses. Efforts to mitigate these losses will enhance the overall flower production, distribution to maximize its economic potential and to sustain valuable contribution for the industry. So, the present experiment on storage of marigold flowers was conducted during 2021 and 2022 at the ICAR- Indian Agricultural Research Institute, New Delhi with an objective to improve the shelf life of flowers by using different packaging materials. The results revealed that in marigold var. Pusa Basanti Gainda, maximum shelf life, high carotenoid content, minimum ion leakage, physiological loss in weight and enzyme activity were achieved in flowers packed in shrink-wrap and stored under low-temperature (6±20C) conditions.

First Report of Cucurbit aphid-borne yellows virus infecting five cucurbits in India.

Cucurbits are among the most popular vegetables cultivated globally. They have high economic importance, especially in India, where they are cooked and eaten as vegetables (Dhillon et al. 2016). In February 2023, yellowing symptoms were observed on cucurbitaceous species, viz. Trichosanthes cucumerina (Snake gourd - SG), Luffa acutangula (Ridge gourd - RG), Lagenaria siceraria (Bottle gourd - BG), Luffa aegyptiaca (Sponge gourd - SPG) and yellow chlorotic spots were recorded on Benincasa hispida (Ash gourd - AG) growing in the experimental farm at the Indian Agricultural Research Institute, Regional Station, Pune (Supplementary Figure 1). The average disease incidence ranged from 5% to 30%. A total of 175 leaf samples, including thirty symptomatic and five asymptomatic plants of each cucurbit, were collected and tested by DAS-ELISA using antisera against cucurbit aphid-borne yellows virus (CABYV) (DSMZ, Germany), cucurbit yellow stunting disorder virus (CYSDV) (Arsh Biotech, India), cucumber mosaic virus (CMV), zucchini yellow mosaic virus (ZYMV), and papaya ringspot virus (PRSV) (Agdia, USA). All 150 symptomatic cucurbit samples tested positive for CABYV, while five samples from SG, 14 from RG, two from AG, and 11 from SPG hosts were also positive for PRSV. Asymptomatic samples were negative for all viruses tested. In order to further confirm the presence of the virus, total RNA was extracted from ten samples of each cucurbit host that were positive only for CABYV and the asymptomatic samples using the RNeasy Plant Mini Kit (Qiagen, Germany) as per the manufacturer's protocol. Two-step RT-PCR was carried out using the extracted RNA and CABYV-specific primers, amplifying c. 484 bp of the coat protein gene region (Boubourakas et al. 2006). Amplicons of expected size were obtained in all symptomatic samples, whereas the asymptomatic samples tested negative. Three amplicons obtained from positive samples from each of the cucurbit species were directly sequenced and found to be identical to each other. A representative virus sequence obtained from each cucurbit was deposited in GenBank (Snake gourd - OQ921128, Ridge gourd - OQ921127, Bottle gourd - OQ921126, Ash gourd - OQ921125, Sponge gourd - OQ921129). In BLASTn analysis, the isolates shared from 94.23 to 100% nucleotide identities with the Indian CABYV isolates of various cucurbits and clustered closely with other Pune isolates in the phylogenetic analysis (Supplementary Figure 2). CABYV (genus Polerovirus) is a single-stranded positive-sense RNA virus, and is known to infect and cause severe economic losses in cucurbits worldwide. Previously, occurrences of CABYV have been reported in cucurbits such as watermelon, bitter gourd, cucumber, squash, teasel gourd, and muskmelon in India (Nagendran et al. 2022; Tripathi et al. 2023). It has also been reported to infect a weed species - Abelmoschus moschatus from the same geographical region (Verma et al. 2023). To our knowledge, this is the first report of the natural occurrence of CABYV in snake gourd and ridge gourd worldwide and bottle gourd, ash gourd and sponge gourd in India. The present findings have significant epidemiological importance, as they demonstrate that CABYV is spreading to other cucurbits and occurring widely in India.

Synthesis of promising copper nanoparticles utilizing biocontrol agents, <i>Trichoderma virens</i> and <i>Chaetomium globosum</i>

The pursuit of creating safe and efficient pesticides remains an ongoing aspiration. Recently, the potential efficacy of metal nanoparticles against diverse phytopathogens has come to light. Commonly used methods, viz. chemical and physical means of nanoparticle synthesis are associated with a range of drawbacks. Fortunately, the biological synthesis method ensures safe and non-toxic nanoparticles. The present study was carried out during 2022–23 at ICAR- Indian Agricultural Research Institute, New Delhi, which documented the successful synthesis of copper nanoparticles (CuNPs) utilizing the supernatant of potent fungal biocontrol agents, viz. Trichoderma virens and Chaetomium globosum. The reduction in the size of copper was determined by UV-Vis spectroscopy. The change in colour of the reaction mixture confirmed the reduction in the size of particles. Characterization using TEM measured spherical CuNPs of the size range 8 to 100 nm depending on the CuSO4 concentration used. Furthermore, Fourier Transform Infrared Spectroscopy (FTIR) unveiled the presence of several functional groups that plays pivotal role in reducing and stabilizing particle size. The in vitro assay conclusively demonstrated the effectiveness of biosynthesized CuNPs, with significant inhibition at a concentration of 10 µg/ml in the case of Xanthomonas euvesicatoria and at 50 µg/ml in the case of Enterobacter cloacae. Our study marks the first instance of synthesizing CuNPs through the utilization of two aforesaid fungal species holding significant promise for antibacterial applications.

Identification of resistant sources against bakanae disease in short grained aromatic rice (Oryza sativa)

An experiment was conducted during rainy (kharif) seasons of 2019 and 2020 at the research farm of ICAR Indian Agricultural Research Institute, New Delhi to screen 90 genotypes of scented short grained rice (Oryza sativa L.) for Fusarium fujikuroi resistance. Genotypes Kankjeer A, Lectimanchi-A, Sumati, Pankhali-203, GR-102, NWGR- 3042, Geetanjali, R 1432-261-105-2-1-2, Khaskani, C-4-63-G, Calrose 76, JJ 92, Koliha, Hari Shankar, Kusuma, IR 74717-3-3-1-3, IR 74725-115-3-3-3, IR 74728-134-1-1-3, Hansraj, Anterved and GAR-1 were identified as moderately resistant with the disease rating of 3 in both the years of evaluation. Further, a set of genotypes with different disease response was evaluated for different parameters including root length, shoot length, number of fibres/threads in roots, days of symptom appearance and area under disease progress curve (AUDPC). Disease severity was observed to be significantly correlated (r = 1.0) with AUDPC and days required for the symptom appearance (r = 0.95). Results indicated that apart from the disease severity, AUDPC could also be considered as a one of the component for the bakanae disease resistance. The resistant sources identified in the present study can be utilized in rice breeding programme against bakanae disease.

Effect of Diverse Production Systems on Growth, Yield and Economics of Indian Mustard (Brassica juncea (L.) Czern and Coss) Varieties

An agronomic experiment to study the effect of diverse production systems on growth, yield and economics of Indian mustard varieties was conducted in the research farm of Division of Agronomy, ICAR–Indian Agricultural Research Institute (IARI), New Delhi, India during rabi season of 2021. The field experiment was laid-out in split-plot design in fixed layout with three replications. The field experiment comprised four main plot treatments (Production systems: Organic Management System (OMS), Integrated Crop Management (ICM), Conventional System (CS) and Conservation Agriculture (CA) and three sub-plot treatments (Mustard varieties-PM 26, PM 28 and PDZ 1). The results revealed that the plant height (cm), Dry matter accumulation (DMA), Leaf area index (LAI) of different varieties of Indian mustard under diversified production scenarios was significantly (p<0.05) influenced at 30, 60 90 days after sowing (DAS). There was almost 14% increase in seed yield was recorded under ICM compared to CS. Among the mustard varieties, PM 26 resulted in maximum seed yield (2206 kg/ha), closely followed by PM 28 (2123 kg/ha), while least seed yield was recorded under PDZ-1. Under OMS and ICM higher harvest index i.e., 0.23 and 0.24 respectively was observed which was higher than CS (0.22) and CA (0.20). The maximum net return (NR) was obtained under ICM (Rs 76583/ha) and among the varieties, PM 26 gave maximum NR of Rs 76060/ha. ICM and CA resulted in higher B:C ratio (2.87 and 2.97 respectively) compared to CS and OMS, while among the varieties maximum B:C ratio was from PM 26 (2.87) and least was from PDZ-1 (2.18).

Developing Model for Diffusion of Farmers’ Innovations for Maximizing Farm Income: Indian Agricultural Research Institute Experiences

Indian farmers have also been continuously improving available technologies for more efficient and cost effective farming, which resulted in numerous innovations over the generations and helped in improving farming practices ensuring better livelihood options. The action research was carried from 2015 to 2021 to document, verify, scalability testing, developing sharing and scaling mechanism, identifying support mechanism and finally devising scaling mechanism for higher profits, reduced costs, enterprise development, enhanced employment opportunities and capacities, growth and survival. The results of various interventions showed that FLIs were mostly reconfiguration of existing resources giving incremental adjustments. All innovators studied expressed dissatisfaction with the pre-existing economic returns of the farming thus pushing them to innovate. Economic effect of the farmers’ innovations in terms of changes in income, change in savings of stakeholders, change in capital owned and change in credit availability were expressed on an average. The innovations which were economically viable and found sustainable source of funding were able to translate into entrepreneurial ventures having higher income and profits. The conceptual model for scaling farmers’ innovations was found effective on the basis of experiences and interventions.

Effect of enriched FYM and rice residue compost on growth, productivity and economics of pigeonpea (<i>Cajanus cajan</i>)

A field experiment was conducted during rainy (kharif) seasons of 2020 and 2021 at the research farm of ICAR- Indian Agricultural Research Institute, New Delhi to evaluate the performance of pigeonpea [Cajanus cajan (L.) Millsp] as affected by enriched organic formulations. The experiment comprised of seven nutrient sources, viz. control; 100% RDN through FYM; 100% RDN through improved RRC (Rice Residue Compost); 100% RDN through PHA (Paddy Husk Ash) enriched FYM; 75% RDN through PHA enriched FYM; 100% RDN through PPC (Potato Peel Compost) enriched FYM; and 75% RDN through PPC enriched FYM that were tested in randomized block design and replicated thrice. Significantly higher number of pods per plant was observed with the application of 100% RDN through PHA enriched FYM over control during both the years of study. The same treatment resulted into statistically higher yields of seed (1.89; 1.97 t/ha) and stover (7.83; 8.03 t/ha) over control and remained at par with 100% RDN through PPC enriched FYM and FYM during both the years. Results further indicated that highest gross returns, net returns and net B:C ratio (₹121.2 × 103 and 131.9 × 103/ha; ₹94.9 × 103 and 104.6 × 103/ha; 3.60 and 3.84) were obtained with 100% RDN through PHA enriched FYM over control and remain at par with treatment 100% RDN through PPC enriched FYM and FYM. Significantly maximum amount of available N in soil after harvest of pigeonpea crop was obtained under application of 100% RDN through PPC enriched FYM (229.1 and 231.9 kg/ha) over control. Further, application of 100% RDN through RRC showed superiority in increasing the available K (264.9 and 265.0 kg/ha) content in soil over control and other nutrient sources during both the years.

Influence of spermidine priming on rice (<i>Oryza sativa</i>) seed germinability and vigour under heat stress

Polyamines (PAs) play a vital role in plants' response to various abiotic stresses, including high temperature (HT) stress. The present study was carried out during 2020–23 at the Indian Agricultural Research Institute, New Delhi to explores how spermidine treatment affects rice (Oryza sativa L.) seeds' ability to withstand heat and the availability of sugars for seedling growth during the radicle stage in heat-susceptible (IR64) and tolerant (N22) varieties. The seeds were primed with 1 mM spermidine using PEG (-1 MPa) as the priming medium, followed by exposure to heat stress. Results showed that in unprimed seeds, heat stress significantly reduces the seed germination, vigour and sugar availability in both the varieties and to a greater extent in IR64 compared to N22. This difference resulted in a substantially lower percentage of normal seedlings and seed vigour index in IR64 than in N22. However, spermidine seed priming enhanced thermotolerance in both varieties, more in IR64, equating the normal seedling percentage and seedling growth with control, i.e. without heat stress. The priming treatment also notably augmented α-amylase activity and reducing sugar availability, particularly in N22, enabling better seedling growth under heat stress conditions. This study underscores the importance of seed priming with spermidine to allow the seedlings to tolerate elevated temperatures and maintain better seedling growth due to the enhanced availability of reducing sugars during germination and early seedling growth.

A Comprehensive Review of Nano-Urea vs. Conventional Urea

Conventional chemical fertilizers, notably urea, have long been employed globally to meet the increasing demands for food production. However, the use of conventional urea has raised environmental concerns, including nitrate leaching, global warming, ozone layer depletion, and groundwater pollution. Additionally, there is an overburden on the government in the form of import expenditure. As the global population grows and arable land diminishes, the demand for chemical fertilizers, particularly nitrogen intensifies. Urea production, responsible for a significant portion of the global nitrogen fertilizer demand, contributes to environmental problems such as greenhouse gas emissions and pollution. Researchers advocate for reducing urea demand through energy-efficient fertilizers to address these issues. Nano-fertilizers, characterized by nano-dimensions and slow-release properties, offer a potential solution. They serve as efficient nutrient carriers, minimizing losses through leaching and emissions. Nano-urea, developed by the Indian Farmers Fertiliser Cooperative (IFFCO), stands out with nanometer-sized particles, prolonged shelf-life, and reduced environmental impact. Its adoption holds promise for sustainable agriculture, reducing agro-chemical use and enhancing soil health. Comparing nano-urea to conventional urea reveals higher efficiency, reduced environmental impact, controlled nutrient supply, and economic benefits. Nano-urea's nanotechnology-based innovations offer a transformative approach to crop nutrition, promoting sustainability, environmental conservation, and increased profitability for farmers. The Indian Agricultural Research Institute's experiment revealed that basal nitrogen application at 75% with prilled urea, full phosphorus and potassium, and nano-urea + nano-Zn sprays achieved yields comparable to 100% N + full P and K doses. Embracing energy-efficient novel fertilizers, such as nano-fertilizers, is crucial for achieving sustainable agriculture and meeting global food demands while mitigating environmental impacts.

Impact of tillage and residue management on greenhouse gases emissions and global warming potential of winter wheat in a semi-arid climate

A two-year field study was carried out at the Indian Agricultural Research Institute New Delhi, from rabi 2020-21 to 2021-22, with the aim of examining the impacts of tillage and residue management on yield, greenhouse gases (GHGs) emissions, global warming potential (GWP) and carbon efficiency ratio (CER) of wheat in a split plot design. The results indicated that both tillage and residue management significantly influenced the grain and biomass yield of wheat. In comparison to conventional tillage (CT), no-tillage (NT) resulted in a substantial reduction of CO2-C emissions by 19.9%, while it led to a notable increase of N2O-N emissions by 11.6%. However, there was a notable and significant rise in GHG emissions with crop residue mulching, registering on an average 20.79% higher emissions compared to residue removal for both the years. The GWP was overall lower in case of NT as compared to CT plots. The highest CER was observed in NTR+ (3.07) during 2020-21 and in NTR0 (3.12) during 2021-22 due to lower CO2 emissions and higher C fixation in both years. Therefore, it may be recommended that wheat can be cultivated in a semi-arid environment with no tillage and residue mulching to provide a comparable yield in addition to lower GHG emissions and GWP and higher CER compared to the farmers’ practice of CT and residue removal.

A new species of leafhopper genus Sophonia (Evacanthinae: Cicadellidae: Hemiptera) from India.

A new evacanthine leafhopper of the tribe Nirvanini, Sophonia submodesta sp. n. (Himachal Pradesh: Nauni), is described and illustrated from India. An annotated key is provided for the identification of all 17 species known under the genus Sophonia reported from the Indian subcontinent. Type material is deposited in the National Pusa Collection, Division of Entomology, Indian Agricultural Research Institute (ICAR-IARI), New Delhi, India.

Health risk assessment of aerosol particles (PM2.5 and PM10) during winter crop at the agricultural site of Delhi, India.

For the last few decades, air pollution in developing country like India is increasing, and it is a matter of huge concern due to its associated human health impacts. In this region, the burgeoning population, escalating urbanization and industrialization, has been cited as the major reason for such a high air pollution. The present study was carried out for health risk assessment of aerosol particles (PM10 and PM2.5) and its associated heavy metals of an agriculture farm site at Indian Agricultural Research Institute (IARI) considered to be green urban area in Delhi, India. The concentrations of both PM10 and PM2.5 varied significantly from 136 to 177µg/m3 and 56 to 162µg/m3, respectively at the site. In the present case, the highest PM10 and PM2.5 levels were reported in January, followed by December. The levels of ambient PM10 and PM2.5 are influenced by wind prevailing meteorology. These levels of PM10 and PM2.5 are more than the permissible limits of WHO guidelines of 15 and 5µg/m3, respectively, thereby leading to high aerosol loadings specifically in winters. The PM concentration of the atmosphere was found to be negatively correlated with temperature during the sampling period. The concentrations of surface ozone O3 and NOx in the present study were observed to be high in February and March, respectively. The increasing air pollution in the city of Delhi poses a great risk to the human health, as the particulate matter loaded with heavy metals can enter humans via different pathways, viz., ingestion, inhalation, and absorption through skin. The mean hazard index for metals (Zn, Pb, Cd, As, Cr, and Ni) was observed within the acceptable limit (HI < 1), thereby indicating negligible non-carcinogenic effects to residing population. The carcinogenic risk assessment was conducted for Cd, Pb, and As only, as the concentrations for other metals were found to be quite low. The carcinogenic risk values were also within the limits of USEPA standards, indicating no carcinogenic risks to the health of children and adults residing near the site. This information about the PM pollution at the agricultural site and health risk assessment will serve as a baseline data in assessment of human health impacts due to air pollution at the local scale and can be used for development of mitigation strategies for tackling air pollution.

Population dynamics of fruit flies and correlation matrix with weather and host variables in mango (Mangifera indica) orchards

The present study was carried out in the Mango orchards at Indian Agricultural Research Institute, New Delhi during 2020–2021 and 2021–2022 and aimed at analysing the population dynamics of fruit fly (Bactrocera dorsalis) species after putting the requisite number of methyl eugenol traps (@6 per acre). Weekly monitoring of fruit fly populations was performed and correlated with various weather parameters. Among the fruit fly species, the oriental fruit fly was found to be the most prevalent and abundant, followed by B. zonata, B. correcta, and B. cucurbitae. Fruit fly populations peaked in mango plantations between June and July, coinciding with the ripening time and the occurrence of humid conditions and rainfall. Multiple factors, including weather conditions, the presence of preferred host plants, and alternative hosts, fruits characteristics were found to influence the dynamics of fruit fly populations. The seasonal trap captures of male fruit flies showed a moderately significant negative correlation (-0.612*) with maximum but significant positive correlation with the minimum temperature (0.701**). However, a positive correlation was observed between relative humidity (r = 0.924**) and rainfall (r = 0.721**) with the fluctuations of fruit fly populations across all the monitored orchard sites.

Effect of row ratios and organic nutrient management on productivity and economics of Indian mustard (Brassica juncea) + chickpea (Cicer arietinum) intercropping system

A field experiment was conducted during winter (rabi) seasons of 2021–22 and 2022–23 at the research farm of Indian Agricultural Research Institute, New Delhi to find out the suitable cropping system with optimum row ratio and nutrient management practice in Indian mustard [Brassica juncea (L.) Czern.] + chickpea (Cicer arietinum L.) intercropping system. Cropping systems i.e. mustard sole; chickpea sole; mustard + chickpea 2:5; mustard + chickpea 5:2 was taken as main plots. Nutrient management practices i.e. control; 60 kg Nitrogen/ha; 20 kg Nitrogen through farmyard manure + leaf manure; 20 kg Nitrogen through farmyard manure + leaf manure + microbial consortia were taken as sub-plots to attain a higher degree of precision. It was observed that though the crop yields of individual crops of mustard and chickpea were the highest in sole crop, but yield of intercropping system in terms of mustard equivalent yield was found to be the highest for mustard + chickpea 5:2 row ratio. Yields of both mustard and chickpea were observed to be the highest in the plots treated with combination of organic manures and microbial consortia i.e. 20 kg nitrogen through farmyard manure + leaf manure @4 t/ha + microbial consortia. Highest gross returns, net returns and benefit-cost ratio were found in mustard + chickpea 5:2 row ratio. Analysis of intercropping indices revealed the highest intercropping advantage in mustard + chickpea 5:2 row ratio when treated with organic manures and microbial consortia. Intercropping systems had land equivalent ratio more than unity, depicting advantage. Aggressivity values showed mustard crop was dominant over chickpea.

Robust NIRS Models for Non-Destructive Prediction of Physicochemical Properties and ageing of Basmati Rice

Aim: To determine physicochemical properties and age of rice by non-destructive technique.&#x0D; Place and Duration of Study: Study was conducted at Division of Food Science and Postharvest Technology, Indian Agricultural Research Institute, New Delhi during 2020 to 2021. &#x0D; Methodology: Rice were kept for accelerated aging at 42.6°C temperature &amp; 71% RH for a duration of 30 days. Changes in four physicochemical properties namely amylose content, volume expansion ratio (VER), water absorption ratio (WAR), and kernel elongation ratio (KER) were evaluated destructively (by spectrophotometer and cooking method) and non-destructively (by spectroradiometer) at every alternate day, during 30 days storage.&#x0D; Results: The physicochemical parameters of rice showed a good correlation with spectral signatures. Subsequently, Principal component Analysis (PCA), Partial Least Square Regression (PLSR), and Multiple Linear Regression (MLR) were used to model the physicochemical changes occurring during the process of accelerated aging using spectral reflectance values. Based on values of Coefficient of determination (R²) and Root mean square error (RMSE) accuracy of models was determined. Predictions with the MLR model resulted in a coefficient of determination (R2) of 0.82, 0.87, 0.9,7, 0.83 and 0.82 with root mean square error (RMSE) of 0.18, 0.13, 0.21, 0.124 and 4.2 for amylose content, VER, WAR, KER, and ageing process respectively for calibration.&#x0D; Conclusion: The study demonstrated the potential of NIRS in non-destructively predicting the physiochemical parameters of rice.

First report of a 'Candidatus Phytoplasma aurantifolia'-related strain associated with faba bean phyllody symptoms in India.

Vicia faba L. commonly known as broad bean or faba bean is one of the most widely grown protein rich legume crops. Out of more than 50 faba bean-producing countries, about 90% production is concentrated in the Asian, European Union (EU), and African region (FAO, 2020). Owing to its high nutritional value, both the fresh pods and dry seeds are consumed. During March 2022, some plants with little leaf and phyllody symptoms such as leaf-like floral structures were observed in the experimental fields of Indian Agricultural Research Institute (IARI), New Delhi (Fig. 1 a, b, c). The twig samples were collected from two individual symptomatic and one from asymptomatic plant. DNA was extracted using CTAB (cetyl trimethyl ammonium bromide) method (Ahrens and Seemüller, 1992; Marzachi et al. 1998) and examined for the association of phytoplasma through nested PCR using the universal primers P1/P7 and R16F2n/R16R2 targeting the 16SrRNA gene (Deng and Hiruki 1991; Gundersen and Lee 1996) and the other set of primers secAfor1/secArev3 and secAfor2/secArev3 targeting secA gene (Hodgetts et al. 2008). The DNA from symptomatic plants resulted the amplicons of 1200bp and 840bp specific to 16S rRNA and secA gene respectively. The gel purified PCR products were cloned into pGEM®-T Easy Vector system (Promega) and outsourced for Sanger sequencing at Agri Genome Labs, Kerala, India. The resultant 16S rRNA sequences (GenBank Acc. No. OP978231, OP978232) and secA sequences (ON715392 and ON715393) were examined through NCBI BLASTn analysis. The 16S rRNA sequences of the V. faba strains shared a minimum of 99.85% similarity with the phytoplasma strain causing little leaf and phyllody disease of sesame in India (MW622017) and a maximum of 100% sequence identity with the Vigna radiata phyllody and necrosis phytoplasma strain of Jodhpur (OP935760) India, whereas the secA gene sequences showed 100% identity with Tephrosia purpurea witches'-broom phytoplasma (MW603929) from China and a minimum of 91.14% similarity with 'Candidatus Phytoplasma aurantifolia' (MW020541) from India. The pairwise comparison results were completely in support of the corresponding phylogenetic sequence analysis results of 16SrRNA and secA gene sequences of faba bean strains in comparison with other strains retrieved from GenBank database, wherein the faba bean strains got clustered with 16SrII-D subgroup related strains (Fig. 2 a and b). Virtual RFLP analysis through iPhyClassifer tool through in silico digestion of R16F2n/R2 region of 16S rRNA gene of the faba bean strain using 17 restriction endonuclease enzymes resulted in the RFLP profiles similar to that of the profile of phytoplasma subgroup 16SrII-D (Y10097: papaya yellow crinkle) used as reference strain with a similarity coefficient value of 1.0. All the results of this investigation confirmed the association of 'Candidatus phytoplasma aurantifolia' (16SrII-D) with the diseased faba bean plants in this study. Previous reports of phytoplasma infecting faba bean include a group 16SrIII strain detected in Spain in 2004 (Castro and Romero), a subgroup 16SrII-D strain detected in Sudan in 2012 (Alfaro-Fernandez et al.), a group 16SrII strain detected in Saudi Arabia in 2014 (Al-Saleh and Amer), and subgroup 16SrIII-J strains detected in Egypt in 2014 (Hamed et al.) and in Peru in 2021 (Torres-Suarez et al.). To the best of our knowledge, these findings, document the first report of the association of 'Candidatus Phytoplasma aurantifolia' (subgroup 16SrII-D) with faba bean plants in India. This report necessitates further research on the status of distribution of this phytoplasma strain in other locations and hosts in the country so as to develop possible strategies to contain its further spread and management of the disease.

Sword Bean (Canavalia gladiata): a new host of Bean common mosaic virus.

Sword bean (Canavalia gladiata) is an underutilized legume that has the potential to become an important food source owing to its wide range of nutritional and medicinal properties. In May 2023, symptoms induced by a possible virus infection such as mosaic, mottling and vein banding were observed on the leaves of about 20% of the Sword bean plants growing at the experimental research farm of the Indian Agricultural Research Institute in Pune, Maharashtra, India. Symptomatic and asymptomatic samples were screened by ELISA for the presence of Potyvirus, Cucumber mosaic virus and Tobacco mosaic virus. All symptomatic samples tested positive for Potyvirus in ELISA as well as in RT-PCR assay using the universal potyvirus primer pair (CPUP /P9502) which amplify c. 700bp of the partial coat protein region and 3'UTR. Asymptomatic samples tested negative for all tested viruses in both serological and molecular assays. BLASTn sequence analysis of the amplicons revealed that the sequence shares more than 98% identity with an Indian isolate of Bean common mosaic virus (BCMV). Sequence analysis enabled the identification of the Potyvirus as BCMV. Furthermore, the present Sword bean isolate clustered with other BCMV isolates in the phylogenetic analysis. In the present study, BCMV was found to be naturally infecting Sword bean for the first time in the world. This is of epidemiological importance, as BCMV is known to cause significant yield losses in legumes and could severely hamper Sword bean production.