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Giant salvinia (Salvinia molesta) is a problematic aquatic fern found in wetlands. Recently, severe infestation of the weed has been observed in the low-lying rice fields in India. An experiment was conducted at Kerala Agricultural University to investigate the effectiveness of different rice herbicides and soil amendments for managing salvinia. The trials were conducted in tanks, and a few effective herbicides were subsequently tested in the field. Changes in major water quality parameters were also monitored. The tank study comprised 15 treatments; lime and gypsum (each at 0.1 kg/m²), acetic acid, salicylic acid, NaCl, and CuSO₄, (each at 5% strength), and rice herbicides such as carfentrazone-ethyl (0.02 and 0.04 kg/ha), 2,4-D amine (1 kg/ha), cyhalofop-butyl + penoxsulam (0.15 kg/ha), florpyrauxifen-benzyl + cyhalofop-butyl (0.15 kg/ha), butachlor + penoxsulam (0.82 kg/ha), glufosinate-ammonium (0.3 and 0.5 kg/ha) along with an untreated check. In tank study, glufosinate-ammonium, carfentrazone-ethyl, cyhalofop-butyl + penoxsulam, florpyrauxifen-benzyl + cyhalofop-butyl, butachlor + penoxsulam, acetic acid, salicylic acid, and CuSO₄ gave more than 80% salvinia control. However, regrowth was observed in acetic acid, salicylic acid, and CuSO₄. Under field conditions, the weed control efficiency of all the treatments were more than 80%. Salvinia competition resulted in 55% reduction in rice grain yield. Though noticeable changes in water pH and EC were observed after applying lime, gypsum, and CuSO₄, these alterations did not suppress the salvinia growth. Effective management of salvinia infestation in wetland rice can be achieved through post-emergent spray of premix herbicides; florpyrauxifen-benzyl + cyhalofop-butyl, cyhalofop-butyl + penoxsulam, pretilachlor + pyrazosulfuron ethyl, butachlor + penoxsulam, or carfentrazone-ethyl or florpyrauxifen-benzyl, along with a wetting agent. For pre-plant control glufosinate-ammonium is a suitable herbicide.

Plant diseases must be controlled to maintain food supplies and sufficiently nourish the global population. Farmers often rely on synthetic pesticides to protect crops. Irrational use of conventional pesticides leads to detrimental effects on ecosystems including environmental pollution, harm to human health and development of bioagressor resistance. The remedy for these catastrophic ordeals lies in sustainable agriculture providing ecosystem services, including biological pest management using live organisms or natural substances. Botanical and microbial-based biopesticides are good choices for crop protection, protecting crops from the vast array of bioagressors in an eco-friendly manner using a range of mechanisms. Furthermore, they display several advantages over synthetic pesticides including target specificity, minor toxicity and biodegradability. However, major challenges hinder their commercial success. A promising approach in the context of developing novel effective biopesticides is to combine botanicals and entomopathogens. Combinations often display synergism, resulting in higher control of bioagressors at lower doses. Furthermore, the combination of agents with differing mechanisms of action help to delay resistance development in bioagressors. The combinations of botanical and microbial agents must be carefully designed to obtain synergistic formulations. Hence, choosing compatible agents, the right combination ratio and the appropriate application time and technique is essential. The efficacy of botanical and microbial combinations must be validated in in situ conditions, along with the investigation of their effect on beneficial non-target organisms. Incorporating novel biopesticides from a portfolio of botanicals and microbials into pest management advances research on biological control of bioagressors and accentuates expansive circularity of sustainable agriculture.

The study investigated the effects of five plant extracts on tomato seed germination, with a focus on their ability to neutralize bacterial and fungal seedborne pathogens. Pathogenic and non-pathogenic microorganisms were isolated and identified from the tomato seeds. To assess the effect of the plant extracts on the health of the seedlings and the level of contamination, ten sterile seeds were soaked in each plant extract for ten and fifteen minutes, respectively, and then placed onto 9 cm diameter sterile Petri dishes covered with filter paper. The germination of tomato seeds treated with aqueous extracts of Rumex tuberosus and Artemisia dracunculus at concentrations of 10% and 15% for 15 min each was compared in a five-replication pot experiment. Significant increases in plant height and root length were observed at 15% concentration of both extracts compared to the control, indicating antimicrobial activity against seedborne pathogens. Major compounds in the extracts were identified by Gas Chromatography-Mass Spectrometry (GC-MS) analysis, including Estra‑1,3,5,7,9,15-hexaen-17-one, 3‑methoxy and palmitic acid. According to these results, extracts from A. dracunculus and R. tuberosus may have antimicrobial qualities that improve plant growth overall, vigor index, and seed germination.

Asia produces the majority of the world’s rice (Oryza sativa L.), one of the utmost vital fundamental food crops, with 90% of worldwide production. Because of increases in average temperature, climate change has a negative impact on rice yield. It is essential to develop such verities of rice that have potential to meet challenges of environmental changes like heat stress etc. This research was approved to investigate heat tolerance ability of rice genotypes on the basis of morpho-physiological attributes at the experimental field area of Islamia University of Bahawalpur. Using a randomized complete blocked design (RCBD) and two sets of plots (one in early sowing rice, other plot goes under late sowing rice condition) with five replications was applied to study 102 genotypes of rice under heat stress. The days to heading, days to maturity, no. of panicles, flag leaf area, grain weight per panicle, no. of grains per panicle, 1000 grain weight and grain yield per plant were positively correlated among themselves under both early sowing and late sowing conditions. Results revealed that, out of 14 principal components (PCs), the first five PCs were showed significant genetic variation under both conditions. The first five PCs displayed 71.1% and 68.9% total variance in the examined germplasm under early and late sowing locations respectively. Based on PCA, 05 heat-tolerant and five heat-susceptible genotypes were identified. There is a significant difference in all the studied rice morphological and physiological traits. Effect of high temperature (heat stress) was observed in both early (normal) and late sowing (heat stress) environments. As a result of these findings selection based on these qualities is not appropriate for heat tolerance. The best performing germplasm under heat stress can be a desirable genotype to generate high yield and used for future breeding programs and early sowing of rice genotypes recommended in this study will be effective for developing heat tolerant rice varieties.

Onion thrips, Thrips tabaci Lind. (Thysanoptera: Thripidae) is a major pest of onion worldwide. It damages onion, Allium cepa L., both directly and indirectly, which leads to significant output losses. In 2022, research was conducted in a private onion field in the Delta region, Egypt, to evaluate the efficacy of bioinsecticides and synthetic insecticides and to evaluate the efficacy of macro- and micronutrient in determining treatment effects on onion thrips populations.

Injury caused by onion thrips is often not severe enough to warrant the application of numerous pesticides to crops in the Delta region of Egypt. Spinosad (Tracer 24% SC) and spinetoram (Radiant 12% SC) were used as bioinsecticides, and Pyridalyl (Pleo 50% EC) was used as a synthetic insecticide for managing onion thrips populations. The greatest decrease in infestation was achieved by the application of the chemical insecticide (Pyridalyl) Pleo 50% EC and the bioinsecticide (Spinosad) Tracer 24% SC. The greatest decrease in infestation was achieved by the application of the micronutrient boron.

Phytoremediation techniques include phyto-de-salinization, phytodegradation, phytoextraction, phyto-filtering, and phyto-volatilation. The phytoremediation technique is considered a promising method to remediate saline soils. The study was conducted with two concentrations of saline soil (50 and 100 mM) with one control, followed by treatment of two isolates (Azospirillum brasilense and Pseudomonas fluorescence). The experiment was conducted in a randomized complete block design using two hybrids (Hysun-33 & Hysun-39). The inoculation of Azospirillum brasilense increased the total biomass production, flowering characteristics, and yield of sunflowers. The study parameter’s result showed that using plant growth-promoting rhizobacteria (PGPR) gives successful vegetative growth with good flowering characteristics and induced salt tolerance in sunflowers. So, bacterial isolate Azospirillum brasilense conformed to better vegetative growth and flowering than isolates of Pseudomonas fluorescence. There was an increase in antioxidants, e.g., catalase, peroxidase, ascorbate peroxidase, and proline content, and a decrease in hydrogen peroxide content of plants by inoculation of Azospirillum brasilense and Pseudomonas fluorescence. Decreased growth at higher salinity levels causes hyper-ionic and hyperosmotic stress and can lead to plant demise. From the results obtained, it could be recommended that Azospirillum brasilense be used to induce salt tolerance in sunflower (Helianthus annus L.) cv. “Hysun-33” under high salinity levels increases vegetative growth, flowering character, yield, and quality of sunflower.

Bio-fertilizers (BF) and amino acids (AA) improve plant growth by activating antioxidant enzymes and establishing a favorable metabolic environment to maintain physiological balance and drought stress mitigation. This experiment aimed to assess the influence of some BF and AA on peanuts (Arachis hypogaea L.) under drought stress. It was conducted during 2018–2019 as a split-split plot based on a randomized complete blocks design with three replications in the experimental field of the Agricultural and Natural Resources Research and Education Center of Guilan province, Rasht, Iran. Three irrigation regimes including irrigation after 75 (IR75), 100 (IR100), and 125 (IR125) mm evaporation from class A evaporation pan, four levels of BF including no application of bio-fertilizers as control (Z0), Arbuscular mycorrhiza (AM), Azospirillum brasilense (AB), Pseudomonas fluorescens (SF) and four levels of AA including no application of AA as control (Z0), Aminol-Forte (AF), Humi-Forte (HF) and Pro-Amin (PA) comprised experimental treatments as main plot, sub-plot and sub-sub plot, respectively. Peanut seed yield (SY) decreased under intensive drought stress. In 2018 and 2019, peanut SY increased by 43.34 and 38.08% in IR75 compared to control, under the interaction of AB×HF and SF×HF, respectively. The interaction of AB and HF increased antioxidant enzymes and improved SY under drought stress, which can be considered an innovation. Hence, the application of AB and HF could be recommended to enhance peanut SY under similar climatic conditions.

A study assessed the potential for using cumulative growing degree days (CGDD) to predict the weed emergence periodicity of three weed species: Argemone mexicana, Brassica tournefortii, and Rapistrum rugosum. Weed emergence was monitored regularly by placing 200 fresh seeds of each weed species on the soil surface. Weed emergence data was fit using a three-parameter sigmoidal Gompertz model. The CGDD required for 50% emergence of A. mexicana ranged from 3380 to 5302, depending upon the seasonal variation in temperature and rainfall. The majority of emergence appeared from March to June. The seeds of A. mexicana exhibited dormancy, as the majority of seeds germinated in the second season. The CGDD required for 50% emergence of B. tournefortii ranged from 824 to 2311, depending upon the seasonal variation in temperature and intensity of rainfall. Most cohorts of B. tournefortii appeared in the first season from February to June, indicating little dormancy in seeds. The CGDD required for 50% emergence of R. rugosum ranged from 2242 to 2699, depending upon weather parameters (temperature and rainfall). The main cohorts of R. rugosum appeared from February to June, and 60% of seeds germinated in the first season, while 40% germinated in the second season, indicating dormancy in seeds. The coefficients of determination for the model verification on the emergence pattern of three weeds were > 85%, suggesting that CGDD are good predictors for the emergence of these weeds. These results suggest that forecasting the emergence of three weed species on the basis of CGDD and rainfall patterns will help growers to make better weed management decisions.

Cotton is a highly sensitive crop to drought stress. Consequently, it is crucial to devise strategies that optimize crop production in conditions of limited water availability. While potassium silicate has demonstrated effectiveness in mitigating drought stress in various crops, its specific impact on different cotton cultivars under drought conditions remains not fully clarified. This research aimed to assess the efficacy of six potassium silicate levels (0, 100, 200, 300, 400 and 500 mg L⁻¹) on four cotton genotypes (Zong main-113, Xin Nong-525, Xin lu Zhong-55, and Xin lu Zhong-66) under two field capacity levels (80% and 50% FC) in a sand culture. Foliar applied potassium silicate significantly improved photosynthetic efficiency, shoot biomass, root biomass, and leaf area under water stress (50% FC). The most substantial reduction in H₂O₂, malondialdehyde levels, and electrolyte leakage was recorded with potassium silicate applied at a rate of 400 mg L⁻¹. This concentration effectively mitigated reactive oxygen species accumulation, safeguarding plants against oxidative damage at 50% FC. Furthermore, potassium silicate contributed to maintaining water status, resulting in increased leaf water content and elevated water-soluble proteins in cotton plants. The order of drought resistance (50% FC) with the application of potassium silicate at 400 mg L⁻¹ was Zong Mian-113, Xin Nong-525, Xin lu Zhong-55, and Xin lu Zhong-66. The findings could help in selection of drought resistance cultivars of cotton in water limited conditions.

Currently, many techniques to alleviate the negative effects of water stress, specifically drought, on plants are frequently the subject of research. In this study, the effects of two different plant growth-promoting rhizobacterial (PGPR) species isolated from arid and semiarid areas whose activities under water stress were determined in a preliminary study on several physiological properties and nutrient uptake of watermelons grafted onto different rootstocks were investigated under deficit irrigation. In this study, the performance of two PGPRs (B₁: Paenarthrobacter aurescens and B₂: Pseudarthrobacter polychromogenes) inoculated into ungrafted watermelon (R₀ (Citrullus lanatus (Thumb.) Matsum and Nakai cv. Crimson Tide, CT)) and grafted watermelons (R₁: CT grafted onto citron watermelon rootstock (Citrullus lanatus var. Citroides) and R₂: CT grafted onto the hybrid rootstock TZ-148 (Cucurbita maxima Duchesne × Cucurbita moschata Duchesne)) were studied under different irrigation levels. Severe water stress negatively affected the physiological characteristics, such as stomatal conductance (gs) and photosynthesis efficiency (QPSII), of watermelon plants. Moreover, the contents of leaf mineral nutrients such as N, P, and K decreased significantly with increasing water stress. On the other hand, rootstocks improved the performance of sweet watermelon in terms of macronutrients such as N, K, and Mg and micronutrients such as Fe and Cu. Moreover, the drought-tolerant rootstocks (R₁ and R₂) used in this study protected watermelon plants against the negative effects of water stress by reducing gs compared to that of ungrafted plants. Moreover, although rhizobacteria did not have a significant effect on the gs, QPSII, or leaf water potential (LWP) of watermelon, they enhanced the uptake of minerals such as macro- and micronutrients from the soil by plants. Under full irrigation and particularly deficit irrigation, P. polychromogenes (B₂) increased the contents of macronutrients such as Mg and K, while P. aurescens (B₁) increased the contents of micronutrients such as Fe, Cu, Mn, and B in watermelons. Our results revealed that these two rhizobacterial species, which were isolated from arid and semiarid areas, contribute to the nutrient uptake of watermelon plants grown under water stress.