ICAR-Indian Agricultural Research Institute Research Articles

Interactive effect of ambient and elevated levels of tropospheric ozone, nutrition and PGPR on growth and yield of chickpea (Cicer arietinum)

An experiment was conducted during 2020 and 2021 at ICAR-Indian Agricultural Research Institute, New Delhi, to study the interactive effect of nutrient and PGPR (Plant growth promoting rhizobacteria) on growth and yield of chickpea (Cicer aeritinum L.) cv. Pusa 3043 under ambient and elevated levels of ozone in FAOE (Free air ozone enrichment). A loss of 15–16% in dry matter production was observed under elevated ozone (EO3) when compared to ambient ozone (AO3) conditions. Seed treatment with PGPR was found to compensate for this loss as an increase in seed yield 18–19% was observed over untreated seeds. In terms of seed yield, the PGPR treatments with 75% nitrogen showed significant improvement compared to the recommended dose of fertilizer (RDF) application. A yield increase of 12% and 14% was observed with PGPR like RPAN8 (Anabena laxa) and An-Rh (Anabena torulosa with Mesorhizobium ciceri) (chickpea rhizobium) respectively, suggesting an advantage of an–Rh over RPAN8 under EO3. A combination of both PGPRs outperformed the individual PGPR, showing a 19% yield increase over RDF. This proves the potential of seed treatment with PGPR (RPAN8 and An-Rh) in ameliorating tropospheric ozone-induced stress in chickpea plants.

Assessing genetic diversity of tomato (Solanum lycopersicum) genotypes cultivated under protected condition

Present study was carried out during 2018–19 and 2019–20 at ICAR-Indian Agricultural Research Institute, New Delhi to evaluate 16 quantitative and qualitative traits of 36 genotypes of Tomato (Solanum lycopersicum L.) and to examine the genetic variability and character association between yield and its component traits. This investigation involved correlation and genetic divergence analyses to gain insights into the relationships among the various traits. The variance analysis revealed notable variations among genotypes, indicating a substantial level of genetic diversity among them. Among the genotypes, 178 and 115 were found promising for both yield and quality traits. Genotype no. 178 was found superior for fruit weight and yield. The principal component analysis indicated that the first 3 components i.e. component 1 (equatorial diameter, average fruit weight and fruit weight uniformity); component 2 (number of locule and equatorial/polar index); and component 3 (number of fruit and number of fruit/cluster) collectively accounted for 81.48% of the variability. The yield exhibited significant positive correlation with average fruit weight (g), pericarp thickness (cm), polar diameter of fruit (cm), equatorial diameter of fruits (cm) and average fruit weight after each harvest (kg).

Zinc uptake in rice (Oryza sativa)-wheat (Triticum aestivum) cropping system under the influence of microbial consortia (Pusa decomposer) mediatedin situ rice straw management options

A field experiment was conducted during the rainy (kharif) and winter (rabi) seasons of 2019–20 and 2020–21 at research farm of ICAR-Indian Agricultural Research Institute, New Delhi to study the effect of various crop establishment methods and microbial consortia (Pusa decomposer) mediated in situ rice straw management options on zinc (Zn) concentration and uptake in rice (Oryza sativa L.) (cv. Pusa Basmati 1509) and wheat (Triticum aestivum L.) (cv. HD 2967). The experiment was laid out in split-plot design (SPD) with 3 replications having 2 main plot (main factor) treatments, viz. aerobic rice (AR); and conventional transplanted (CT) rice in wet season; and 7 sub- plot (sub-factor) treatments, viz. Clean cultivation (removal of paddy straw); Paddy straw incorporation (PSI); Paddy straw mulching (PSM); PSI + Pusa decomposer (PD); PSM + PD; PSI + urea @20 kg/ha; and PSI + PD + urea @10 kg/ha in dry season. Findings showed that, in rice the zinc concentration (18.51 and 20.30 mg/kg in grain; 57.02 and 57.81 mg/kg in straw) and uptake (78.38 and 89.81 g/ha in grain; 427.1 and 434.6 g/ha in straw) were significantly superior in CT rice than AR in main plots during both the years of experiments. However, sub-plot treatments were non-significant in the zinc concentration and uptake. In wheat, among in situ rice straw management options (sub- plots), paddy straw incorporation + Pusa decomposer + Urea @10 kg/ha treatment significantly resulted in higher Zn concentration (38.08 and 39.03 mg/kg in grain; 28.24 and 29.01 mg/kg in straw) and uptake (185.0 and 191.9 g/ha in grain; 234.2 and 242.6 g/ha in straw) compared to other treatments and control (clean cultivation). The principal component analysis revealed that Zn uptake positively correlated with straw and grain yields in rice and wheat. Thus, the same treatment was found to be a better option for higher Zn concentration and uptake in the rice-wheat cropping system.

New records of family Chalcididae (Hymenoptera: Chalcidoidea) on vegetables ecosystem from New Delhi, India

ABSTRACT Chalcidids are important primary parasitoids for controlling several economic insect pests, and some are secondary parasitoids. These specimens were collected by using different traps during the period extending from November 2021 to October 2022, from various vegetable crops grown in different localities at ICAR-Indian Agricultural Research Institute (ICAR-IARI), New Delhi. The larvae and pupa of the pests were brought to the lab and reared for the emergence of parasitoids at 25 ± 0.5°C and relative humidity of 65 ± 5%. Eleven species belonging to four genera in three subfamilies were identified: Brachymeria bengalensis (Cameron, 1897); B. hime (Habu, 1960); B. kassalensis (Kirby, 1886); B. lasus (Walker, 1841); B. minuta (Linnaeus, 1767); B. podagrica (Fabricius, 1787) (Brachymeriinae); Dirhinus anthracia (Walker, 1846); D. auratus Ashmead, 1905 (Dirhininae) and Antrocephalus sepyra (Walker, 1846); Kriechbaumerella kraussi (Narendran, 1989); K. rufimanus (Walker, 1860) (Haltichellinae). Among them six species are newly recorded from New Delhi. On the other hand, B. hime was recorded for the first time as a parasite on Leucinodes orbonalis Guenée (Lepidoptera, Crambidae).

Brown manuring in maize (Zea mays): Effects on weed interference and crop productivity

A field experiment was undertaken during rainy (kharif) season 2017 at ICAR-Indian Agricultural Research Institute, New Delhi to study the effects of brown manuring on weeds and maize (Zea mays L.) productivity. Season-long weed infestation (~unweeded control) resulted in the highest reduction (~41%) in grain yield of maize. Among the brown manuring (BM) treatments, growing of 1:1 mixture of Sesbania bispinosa (12.5 kg seed/ha) + Crotalaria juncea L. (12.5 kg seed/ha) supplemented with 2,4-D 0.5 kg/ha applied at 35 DAS, resulted in the highest reduction in weed density (~93%) and dry matter (~94.4%). This BM, in these regards, was comparable with the atrazine + hand weeding (HW) at 35 days after sowing (DAS) and weed-free control treatments. All BM treatments suppressed noxious weed Cyperus rotundus, which was poorly or not controlled by the recommended tank-mixture of atrazine and pendimethalin. Weed-free control resulted in the highest values of maize plant dry-matter (~210.6 g/plant), cob weight (~155.9 g/cob), and grain yield (~6.0 t/ha). The atrazine + HW, Sesbania + Crotalaria (12.5 + 12.5 kg/ha) mixture applied with 2,4-D 0.5 kg/ha at 25 DAS, Sesbania 25 kg/ha with 2,4-D 0.5 kg/ha at 25 DAS, and pendimethalin 0.75 kg/ha + atrazine 0.75 kg/ha treatments were comparable with weed-free control on maize grain yield.

Impact of diverse tillage and nitrogen management on growth and yield of conservation agriculture-based wheat (Triticum aestivum)

A study was carried out during the winter (rabi) seasons of 2020–21 and 2021–22 at ICAR-Indian Agricultural Research Institute, New Delhi to assess the effects of diverse tillage and nitrogen management scenarios on growth, development, and yield of a conservation agriculture (CA)-based wheat (Triticum aestivum L.) crop grown in sequence with maize (Zea mays L.). Experiment was conducted in split plot design (SPD) comprised of 3 different tillage practices in main plots [Conventional tillage + residue (CT); Zero tillage + residue (ZT); and Permanent beds + residue (PB)] and 5 nitrogen (N) options in sub plots [Control (zero nitrogen); Recommended dose of N-RDN @150 kg N/ha (50 kg N/ha Basal + 2-equal splits at 37 days after sowing (DAS) and 84 DAS); Green Seeker (GS) based application of N @148 kg N/ha (GS); Urea super granules applied as basal @75 kg N/ha + GS based N application (USG); and Slow release fertilizer as 100% basal application @150 kg N/ha (SRF)] with 3-replications. The findings revealed that in both the seasons, both tillage and nitrogen management approaches significantly affected wheat growth, yield characteristics, and overall yield, whereas the time to anthesis and physiological maturity, and test weight remained unaffected. Within the spectrum of tillage practices, leaf area index (LAI) and yield attributes exhibited the trend PB>ZT>CT. PB recorded the highest grain yield (5159 kg/ha), followed by ZT (4916 kg/ha) and the lowest grain yield was observed with CT (4578 kg/ha). The wheat grain yields were 12.7% and 7.4% higher in PB and ZT, respectively, over to CT. Among nitrogen management options, the grain yield exhibited the pattern USG>N150>SRF>GS>N0. This study emphasizes that adopting conservation agriculture (CA) practices, particularly CA-based permanent beds using urea super granules (USG) for nitrogen management can improve wheat growth and yield.

Pre-storage melatonin treatment maintains cell membrane integrity, reduces fruit browning and decay incidence in guava (Psidium guajava)

An experiments were conducted during 2021–22 at ICAR-Indian Agricultural Research Institute, New Delhi to study the impact of melatonin (MT) on key characteristics of guava (Psidium guajava L. cv. Barafkhana). Guava fruits were treated with different MT concentrations (200, 400, 600 and 800 μM) and stored at 10±1°C with 85–90% RH. The research revealed that treating with 600 μM MT notably decreased polyphenoloxidase activity by 57%, leading to delayed peel browning and also suppressed polygalacturonase (PG) activity by approximately 45% and pectine methylesterase activity by about 73%, resulting in higher firmness (5.33 N). Following a 20-days period of cold storage, significant reductions in electrolyte leakage, hydrogen peroxide accumulation and lipoxygenase activity were observed, thereby preserving cell membrane integrity. Additionally, MT stimulated the antioxidant defense system, boosted proline content accumulation, and enhanced phenylalanine ammonia-lyase activity. Together, these effects contributed to enhanced resistance against postharvest fungal decay (8.75%). In conclusion, MT at a concentration of 600 μM proves to be an effective postharvest treatment for maintaining texture, reducing fruit decay and extending the shelf-life of guava during cold storage.

Determination of insecticide resistance in cotton whitefly in north India

The whitefly, Bemisia tabaci (Gennadius) considered as most destructive pest, poses a significant threat to various crop species globally has developed resistance due to the indiscriminate use of synthetic chemicals. A study was carried out in 2018 at ICAR-Indian Agricultural Research Institute, New Delhi to determine insecticide resistance, in five Asia II 1 populations of B. tabaci from different cotton (Gossypium hirsutum L.) growing regions of north India. The susceptibility of the populations to different insecticide classes, viz. synthetic pyrethroid (cypermethrin); neonicotinoids (imidacloprid and thiamethoxam); thiourea (diafenthiuron) and diamide (cyantraniliprole) were assessed. Results revealed substantial heterogeneity in the responses of these populations to the insecticides. Sriganganagar and Bathinda populations exhibited moderate resistance to cypermethrin, imidacloprid, and thiamethoxam. Low level of resistance was observed in Bathinda and Sriganganagar populations against diafenthiuron. All populations were highly susceptible to cyantraniliprole. No cross-resistance was observed between cyantraniliprole and other insecticides, suggesting its potential as an alternative for managing insecticide resistance. High levels of detoxification enzymes (esterase, cytochrome P450 monooxygenase, and glutathione-S-transferase) in Sriganganagar and Bathinda populations indicated a positive correlation between insecticide resistance and detoxifying enzymes. These findings offer valuable insight for implementing insecticide rotation strategies to combat B. tabaci resistance in India.

First record of Apanteles hemara (N.) on Leucinodes orbonalis Guenée and biodiversity of Hymenoptera parasitoids on Brinjal.

The brinjal fruit and shoot borer (BFSB), Leucinodes orbonalis Guenée (Lepidoptera: Crambidae), is a very detrimental pest that causes significant economic losses to brinjal crop worldwide. Infested brinjal fruits were collected from vegetable fields located at the ICAR-Indian Agricultural Research Institute (ICAR-IARI), New Delhi, India, during two consecutive seasons (2021-2022). The larvae of the pest were brought to the laboratory and reared under controlled conditions of 25 ± 0.5 °C and 70 ± 5% relative humidity, for the emergence of parasitoids. In addition, the survey of Hymenoptera parasitoids in brinjal was conducted utilizing a sweep net and yellow pan trap over the course of two seasons. The results reveal that five parasitoid species were emerged from L. orbonalis viz., Apanteles hemara Nixon, 1965, Bracon greeni Ashmead 1896 (Hymenoptera: Braconidae), Goryphus nursei (Cameron, 1907), Trathala flavoorbitalis (Cameron, 1907) (Hymenoptera: Ichneumonidae) and Spalangia gemina Boucek 1963 (Hymenoptera: Spalangiidae). Out of these, A. hemara and S. gemina were documented as new occurrences in Delhi. Additionally, A. hemara was recorded for the first time as a parasite on L. orbonalis. Trathala flavoorbitalis was observed during both seasons and exhibited higher parasitism reaching 15.55% and 18.46% in July and August 2022, respectively. However, the average parasitism (%) recorded by A. hemara, B. greeni, G. nursei, T. flavoorbitalis and S. gemina was 3.10%, 1.76%, 1.10%, 9.28% and 1.20% respectively. Furthermore, the findings showed a significant (p ≤ 0.01) strongly positive correlation between fruit infestation (%) by L. orbonalis and parasitism (%). The survey indicates the presence of a broad group (19 families and 60 species) of Hymenoptera parasitoids in the brinjal crop ecosystem in Delhi which could be valuable in biological control. In light of these results, this study revealed that A. hemara and other parasitoids identified in this study alongside T. flavoorbitalis would be ideal biocontrol agents within the integrated pest management (IPM) program of BFSB in Delhi.

Studies on comparison of nano-urea and prilled urea for enhancing maize (Zea mays) growth and productivity

An experiment was conducted during the rainy (kharif) season of 2022–23 at the ICAR-Indian Agricultural Research Institute, Hazaribagh, Jharkhand to assess how well nano- urea performs in maize under different field conditions and investigate its compatibility with other N sources. Results showed that root weight (fresh and dry), partial factor productivity (N, P2O5 and K2O), N concentration (grain and stover), grain yield, biological yield and harvest index of maize were all significantly affected by the application of various N rates and nano-fertilizers. The grain yield of maize was comparable to the yield obtained under RDF and 75% of the recommended N + two nano-urea sprays. These findings indicate that the concurrent use of these nano-fertilizers has the potential to reduce N fertilization by as much as 25%. Furthermore, the results highlight the prospect of augmenting biological yield of maize by incorporating 2 nano-urea sprays alongside the prescribed N quantity from prilled urea, as well as full applications of P2O5 and K2O.

Evaluation of urea loaded nanoclay biopolymer composites with Zn and P solubilizing microbes for nitrogen uptake and use efficiency in maize (Zea mays)-wheat (Triticum aestivum) cropping system

A field experiment was conducted during rainy (kharif) 2022 (July 2022–October 2022) and winter (rabi) 2022–23 (November 2022–March 2023) seasons at ICAR-Indian Agricultural Research Institute, New Delhi to evaluate a series of Zn and P solubilizing microbial culture enriched nanoclay biopolymer composite (NCBPC) loaded with nitrogenous fertilizer (urea) and the efficiency of the products for maize (Zea mays L.) and wheat (Triticum aestivum L.). Experiment consisted of 10 treatments, viz. T1, Control; T2, 100% N though urea; T3; T5; T7; and T9, 75% N as urea loaded NCBPC-A (prepared using acrylic acid + acrylamide + mango kernel flour) alone or along with P or Zn or P + Zn solubilizers; T4; T6; T8 and T10, 75% N as urea loaded NCBPC-B (prepared using acrylic acid + acrylamide + maize flour) alone or along with P or Zn or P + Zn solubilizers in a randomized block design (RBD) and replicated thrice. In both maize and wheat crop, highest grain (5.09 and 5.32 t/ha) and straw yield (6.56 and 7.45 t/ha), apparent N recovery (51.26 and 47.26%) and agronomic efficiency (12 and 13.3 kg grain yield obtained/kg N application) were obtained in treatment T10 followed by T9. In addition, total N uptake significantly enhanced by 20.1–28.4% in maize and 22.1–30.8% in wheat (T9 and T10); apparent nitrogen recovery (ANR) improved by 12.9–18.2 and 15.2–21.1% and agronomic efficiency (AE) triggered by 19.5–21.2 and 15.4–20.8% in maize and wheat crops respectively, under T9 and T10 treatments over standard urea fertilization (T2). Thus, the study concludes that, 25% N requirement could be cut down through application of 75% N (urea) loaded NCBPCs in conjunction with Zn or P or Zn + P solubilizing microbial culture as compared to sole urea application under maize-wheat cropping system.

Characterization of gynodioecious Pune selection lines of papaya

Among major global threats to papaya cultivation, papaya ringspot virus (PRSV) is the most challenging one. In the absence of any PRSV resistant commercial papaya cultivar, PRSV management is restricted to minimizing yield losses. ICAR-Indian Agricultural Research Institute, Regional Station, Pune has developed PRSV tolerant dioecious papaya lines, Pune Selection (PS)-1, PS-2, PS-3 and PS-5. Being dioecious these lines have limited acceptability among farmers. Gynodioecious population from these lines were developed and characterized. They are numbered PS-1-1, PS-2-1, PS-3-1 and PS-5-1. These lines were characterized against prevailing commercial gynodioecious cultivar, Red Lady, for five generations. The average plant height of PS-2-1 and PS-5-1 (183 cm) was more than Red Lady (158 cm), however, stem girth of all lines was lesser than Red Lady. The fruiting height of all lines was less than Red Lady (87 cm). Length of the fruiting column of all lines was more than Red Lady (37 cm), except in PS-1-1. Fruit yield of all lines was more than Red Lady (16 kg/plant). Intensity of PRSV infection in Red Lady (48%) was considerably more than all lines. These lines can be used for developing PRSV tolerant gynodioecious papaya variety.

Interactive effect of transplanting time and crop phenology on incidence of brown planthopper and spider population in rice (Oryza sativa)

Brown planthopper (BPH), Nilaparvata lugens (Stal 1854) is a destructive insect pest causing severe yield loss every year in rice (Oryza sativa L.) crop. An experiment was conducted during during kharif (rainy) seasons of 2021 and 2022 at the research farm of ICAR-Indian Agricultural Research Institute, New Delhi to study the effect of transplanting time and crop phenology on brown planthopper (BPH) incidence and spider population in rice. BPH and spider populations were recorded at different phenological stages in early, normal and late transplanted rice. Results showed that a significantly higher mean BPH population was observed in late transplanting in 2021 [54.00±5.31 per hill (nymphs and adults)] and 2022 (40.40±2.62 per hill) compared to normal and early tranplanting. Peak BPH population was observed at the heading (225.60±18.83 per hill) and milking stage (131.00±8.30 per hill) of late transplanted rice in 2021 and 2022, respectively. Likewise, more mean spider population was observed in late transplanting [1.87±0.11 per hill (adults) in 2021 and 2.38±0.08 per hill in 2022]. Two-way ANOVA showed a statistically significant interaction between transplanting time and crop phenology with regard to BPH incidence and spider population in both the years. The highest grain yield was recorded in early transplanted rice (36.08±0.75 q/ha; 35.06±0.49 q/ha) followed by normal (27.53±0.80 q/ha; 28.22±0.75 q/ha) and late transplanted rice crop (17.43±0.82 q/ha; 19.37±0.67 q/ha) respectively during two years. The early transplanted rice crop escaped the peak BPH incidence resulted in increased grain yield. The study demonstrated that both transplanting time and crop phenology influenced the BPH and spider populations.

Assessment of precise nutrient management through nutrient expert on productivity and profitability of zero-till maize

An experiment was conducted during the rainy (kharif) season of 2017 and 2018 at the ICAR-Indian Agricultural Research Institute, New Delhi, to evaluate the effect of tillage and nutrient-management options on yield, nutrient uptake, residual soil-fertility status, and enzymatic activities in maize (Zea mays L.). The zero-tillage with crop residue at 3.5 t/ha (ZT + R) and conventional tillage with crop residue at 3.5 t/ha (CT + R) enhanced the grain yield (6.2–17.0%) of maize compared to CT without residue (4.40 t/ha). High cost of cultivation was recorded in CT + R (44.8 × 103 `/ha), while high net returns were found in ZT + R (37.6 × 103 `/ha). In ZT + R, the addition of wheat residue enhanced N, P, and K uptake in grain by 19.41, 12.81 and 13.92%, respectively over CT. Available N (182 kg/ha), available P (13.8 kg/ha), and exchangeable K (318 kg/ha) were found highest with ZT + R. Nutrient expert system (NES) enhanced the grain yield (5.30 t/ha) and net returns (43.0 × 103 `/ha) compared to no application of nutrients (control) (3.35 t/ha and 17.9 × 103 `/ha) and recommended dose of fertilizer (RDF) (4.70 t/ha and 34.8 × 103 `/ha). Higher activity of dehydrogenase (DHA) (25.9 TPF μg/g/h) and microbial biomass C (130 μg/g) were found with NES. An increase of 57.96–58.4% in N uptake was found with NES over RDF (80.0 kg/ha). The nutrient expert system (NES) and 125% of RDF left higher amount of residual N, P and K in soil than the control. Overall, nutrient expert system under zero-tillage with crop residue at 3.5 t/ha can increase the productivity and profitability in maize.

Evaluation of maize (Zea mays) genotypes under different nitrogen levels in a Trans-Gangetic Plains region

An experiment was conducted during rainy (kharif) seasons of 2021 and 2022 at the research farm of ICARIndian Agricultural Research Institute, New Delhi to study the effects of different genotypes and nitrogen levels on growth and yield of maize (Zea mays L.). Six maize genotypes (‘AH 4271’, ‘DKC 9164’, ‘PJMH 1’, ‘PMH 13’, ‘PC 4’ and Pusa Vivek QPM 9’ Improved (PV QPM 9-I) and 7 levels of nitrogen (0, 40, 80, 120, 160, 200 and 240 kg N/ ha) were evaluated using factorial randomized complete block design with two replications. Results showed that among the genotypes the ‘DKC 9164’ produced the highest kernel yield and resulted in maximum net returns (` 78.0 and 82.8 × 103 /ha) as compared to other genotypes. The growth parameters and yield increased with the increasing level of nitrogen from 0 to 240 kg/ha. Application of nitrogen @240 kg N/ha produced the maximum plant height, total number of leaves, leaf area index and stover as well as biological yield, whereas the maximum kernel yield and net returns (` 91.1 & 97.2 × 103 /ha) were obtained with 200 kg N/ha which was at par with 160 kg N/ha

Effects of Tillage, Mulching and Site-Specific Nutrient Management on Soil Temperature, Flowering, Bulk Density and Soil Organic Carbon in Wheat

The effects of tillage, mulching and site-specific nutrient management on soil temperature, flowering, bulk density, and soil organic carbon in wheat” studied during rabi,2021-22, at the research farm of ICAR-Indian Agricultural Research Institute, New Delhi. The experiment with 24 treatment combinations was laid out in a split-plot design and replicated thrice. The main plot treatments included six different crop establishment methods (conventional tillage without residue, conventional tillage with residue incorporation, zero tillage without residue, zero tillage with residue, permanent raised bed without residue and permanent raised bed with residue retention and sub plot treatments consist of four nutrient management options (STBR, STBR+GS, NE and NE+GS based recommendation). PRB with residue retention has 1-2ºC soil temperature higher up to 70-75 DAS and started to decline after 75 DAS till harvest. Mulching protects the crop from winter and summer stress. Maximum soil organic carbon (SOC) values (0.39%) were noted under ZT+R, which was Higher compared to CT-R after harvest the crop. Soil bulk density (BD) under ZT+R (1.28 g/cm3) was lower as compared to rest of the treatments. Number of days required to 50% flowering was (83.6 DAS) and to 75% flowering was (88.2 DAS) in PRB+R which was on par with other treatments. it was concluded that the combination of maize straw mulch, zero tillage and permanent raised beds were proved fruitful in improving soil thermal properties and soil carbon sequestration.

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.

Evaluation of tree species using Air Pollution Tolerance Index for urban landscaping in Delhi

Air pollution which negatively impacts both human health and the environment is a mountainous challenge before policymakers and city planners in urban areas. Urban landscaping with effective pollution-combating tree species is one of the soundest strategies to mitigate pollution adversaries. However, not all tree species are equally suitable for urban environments due to varying levels of tolerance to air pollution. This study has been designed to evaluate the physiological and biochemical responses of seven commonly occurring tree species in the Talkatora garden (TG) and Income Tax Office (ITO) representing non-polluted and polluted locations in Delhi, respectively applying Air Pollution Tolerance Index (APTI). The current research study was carried out during 2021–22 at the Division of Floriculture and Landscaping, ICAR-Indian Agricultural Research Institute, New Delhi. In tree species understudy, it was recorded that the pH of leaf extract, total chlorophyll, and relative water content was lower in the winter season than summer season except for the ascorbic acid. Ficus religiosa with the highest APTI value (23.23) followed by Pongamia pinnata (20.85) were found most tolerant tree species to air pollution in Delhi during the winter season at the polluted (ITO) and non-polluted (TG) location respectively with a reverse trend for the summer season. Polyalthia longifolia was found most sensitive (bioindicator plant) to air pollution among the seven trees under study owing to the lowest APTI values (11.14 and 12.58) across the seasons at non-polluted (TG) and polluted (ITO) locations respectively. Furthermore, Ficus religiosa with the highest APTI across the locations and seasons was assessed as the best performer, hence, could be the most efficient option for landscaping in polluted and non-polluted areas.

Impact of irrigation and nitrogen management on crop performance, yield and economics of sorghum (<i>Sorghum bicolor</i>) inKandahar region of Afghanistan

In Afghanistan the information on the performance of sorghum crop to applied nitrogen (N) fertilizer coupled with water management are still scarce. Therefore, a field study was carried out during rainy (kharif) season of 2020 at the research farm of Afghanistan National Agricultural Science and Technology University, Kandahar, Afghanistan. Kandahar in collaboration with ICAR-Indian Agricultural Research Institute, New Delhi evaluated the effect of different irrigation scheduling and nitrogen management options on growth, yield and economics of sorghum. The experiment was laid out in a split-plot design with 3 replications consisting of 3 irrigation schedules in main-plots and 4-N rates in sub-plots. Growth parameters of sorghum, viz. plant height, dry matter accumulation, crop growth rate and leaf area index were significantly increased by N120 and N80 compared to N0 plots. Significantly superior yields, viz. seed yield (1546 and 1476 kg/ha), straw yield (5546 and 5467 kg/ha), biological yield (7092 and 6943 kg/ha) and harvest index (21.3 and 21.8%) were observed with N120 and N80 plots, respectively. The N120 and N80 plots remained at par with each other with respect to net B:C ratio (1.87). However, the highest production efficiency (14.7 kg biomass/day) and monetary efficiency (773.90 AFN/day) was obtained with N120 plots. Therefore, the findings of present study suggest that N application @80 kg/ha could be a viable option to attain higher productivity, farm profitability and input-use efficiency irrespective of 2 or 3 irrigations in sorghum in Kandahar region of Afghanistan.

Controlling Phalaris minor with novel pyroxasulfone under conservation agriculture in the north-western Indo-Gangetic Plains

A field experiment was conducted during the winter (rabi) seasons of 2021–22 and 2022–23 at the research farm of ICAR-Indian Agricultural Research Institute, New Delhi to evaluate the effectiveness of pyroxasulfone in controlling resistant Phalaris minor within the maize (Zea mays L.)-wheat (Triticum aestivum L.) cropping system. The experiment consisted a split-plot design involving 3 crop establishment systems (Bed + R; ZT + R and CT + R) and 5 weed management strategies, viz. pyroxasulfone (W1); pyroxsulfone fb metsulfuron + carfentrazone (W2); Sulfosulfuron + metsulfuron (W3); UWC (W4); and WFC (W5), replicated thrice. The results from two-year analysis consistently favoured bed planting with residue, which exhibited the lowest P. minor density and total weed population compared to the other two methods with highest weed control efficiency. Among the various weed management options, the combination of pyroxasulfone fb metsulfuron + carfentrazone recorded significantly lowest P. minor density and higher weed control efficiency, similar to the weed-free check. Additionally, this treatment led to significantly higher dry matter accumulation (68.2 g/m2), ear length (12 cm), test weight (41 g) and grain yield (5.8 t/ha) compared to other herbicide treatments, underscoring its outstanding performance.