RESUMEN
Aims: A field study was conducted to quantify the effect of moisture deficit stress at different critical stages of quinoa and different mitigation approaches were adopted in order to alleviate moisture deficit stress.Study Design: The experiment was designed in split plot design comprising of six main plots (water management) and four sub plots (stress mitigation approaches). The treatments in main plots viz., no irrigation at branching (M1), at ear formation (M2), flowering (M3), grain filling (M4) stages, irrigating at all four stages (M5) and irrigating as and when required (M6), and sub plot treatments viz., soil test-based fertilizer recommendation (STBFR) (S1), STBFR + Salicylic acid spray at 100 ppm (S2), STBFR + rice straw mulching (S3) and integrated nutrient management (S4) were tested.Place and Duration of Study: The experiment was conducted at the Instructional Farm, Odisha University of Agriculture and Technology, Bhubaneswar during Rabi 2021-22.Methodology: Moisture deficit stress was imposed by withholding irrigation water and not irrigating in the defined period. The treatments in the subplots were imposed as per the schedule.Results: Optimal results, including significantly taller plants, elevated relative water content, and increased grain yield, were achieved when irrigation was applied on an as-needed basis (M6). Conversely, the lowest grain yield was observed when moisture deficit stress was imposed during the branching stage of quinoa. This outcome was primarily linked to a more substantial reduction in both relative water content and plant height. Among the various stress mitigation approaches, integrated nutrient management (S4) emerged as the most effective management practice, followed closely by STBFR + Salicylic acid spray at 100 ppm (S2).Conclusion: The result indicated that branching stage is the most critical stage for irrigation in quinoa and integrated nutrient management could be the best approach under moisture deficit stress in quinoa among the other treatments.
RESUMEN
Aims: A field study was conducted to quantify the effect of moisture deficit stress at different critical stages of quinoa and different mitigation approaches were adopted in order to alleviate moisture deficit stress.Study Design: The experiment was designed in a split-plot design comprising six main plots (water management) and four subplots (stress mitigation approaches). The treatments in main plots viz., cut-off irrigation at branching (M1), at ear formation (M2), flowering (M3), grain filling (M4) stages, irrigating at all four stages (M5) and irrigating as and when required (M6), and subplot treatments viz., soil test-based fertiliser recommendation (STBFR) (S1), STBFR + Salicylic acid spray at 100 ppm (S2), STBFR + rice straw mulching (S3) and integrated nutrient management (S4) were tested.Place and Duration of Study: The experiment was conducted at the Instructional Farm, Odisha University of Agriculture and Technology, Bhubaneswar during Rabi 2021-22.Methodology: Moisture deficit stress was imposed by withholding irrigation water and not irrigating in the defined period. The treatments in the subplots were imposed as per the schedule.Results: The lowest leaf area index was recorded when irrigation was withheld at the branching stage (0.61) which was statistically similar to M2 (no irrigation at the ear formation stage) with an average leaf area index of 0.64. Similarly, plants under integrated nutrient management practices (S4) recorded a significantly higher leaf area index (0.92) which was statistically at par with S2 (STFBR + Salicylic acid spray) which was 0.87. The reduction in the TCC was the maximum when stress was applied at the branching and ear formation stage compared to the flowering and grain filling stage. The increment in grain yield by following INM (S4) and STBFR+SA (S2) under drought stress and irrigated control was 23.6% and 17.6%, respectively over fully inorganic nutrient management (S1).Conclusion: The result indicated that the branching stage is the most critical stage for irrigation in quinoa and integrated nutrient management could be the best approach under moisture deficit stress in quinoa among the other treatments.
RESUMEN
Aims: Early blight of tomato (Solanum lycopersicum L.) incited by Alternaria solani is an economically important disease. This paper analyses the efficacy of copper nanoparticles (Cu-NPs) as an alternative to its existing management practices that predominantly rely on toxic fungicides which are potentially harmful to humans and the environment.Study Design: The experiment was conducted in a completely randomized block design with 7 treatments viz. T1:Cu-NPs from tulsi leaves, T2:Cu-NPs from neem leaves, T3:Cu-NPs from bael leaves, T4: Cu-NPs from chemical A (prepared from 0.2 M of Cu(NO3)2.3H2O + 0.2 M Ascorbic acid), T5: Cu-NPs from chemical B (0.2 M Cu(NO3)2.3H2O + 0.2 M CuCl2 + 0.4 N NH4OH), T6: Carbendazim 50 WP as check and T7: Control. Each treatment was tested at two levels of in vitro concentrations (i.e. 300 and 500 ppm) and the treatments were replicated thrice.Place and Duration of Study: Considering the importance of the disease and for developing an effective management strategy, the present study was carried out in the Department of Plant Pathology, College of Agriculture, Odisha University of Agriculture and Technology, Bhubaneswar during 2020-21.Methodology: Stable Cu-NPs were synthesized through three green synthesis methods by using bael (Agel marmelos L.), tulsi (Ocimum sanctum L.), and neem (Azadirachta indica L.) leaves and two chemical synthesis methods (i.e. chemical A and B).Results: The size (diameter) of the Cu-NPs from Agel marmelos, Ocimum sanctum, and Azadirachta indica were 427.4, 1,019, and 246.5 nm, and that from the aqueous solution reduction method and precipitation method were 1,537 and 867.8 nm, respectively. The synthesized Cu-NPs were evaluated against Alternaria solani at 300 and 500 ppm while Carbendazim 50 WP served as the standard check. The Azadirachta indica leaf-derived Cu-NPs at 300 and 500 ppm in the in vitro potato dextrose ager (PDA) medium exhibited the maximum mycelial growth inhibition of 60.24% and 75.9%, respectively. The size of Cu-NPs showed an inverse relation with the antifungal efficacy that indicated greater cellular penetration of smaller nanoparticles whereas much lower inhibition of mycelial growth in Carbendazim 50 WP as a check showed the lowest growth inhibition of 39.75% (300 ppm) and 59.03% (500 ppm).Conclusion: The results thus indicated higher efficacy of nanoformulations at lower concentrations that can be effectively used for the development of new nano-based plant protection agents against the early blight of tomatoes.