Allelopathic potential of bread wheat helps in suppressing the littleseed canarygrass (Phalaris minor Retz.) at its varying densities

In this 2-year field study, we investigated the allelopathic effects of three wheat cultivars (Shafaq-06, Faisalabad-08 and Sehar-06) against different density levels (0, 100, 200 and 300 plants m^?2) of littleseed canarygrass (Phalaris minor Retz.). Crop was sown on 1 and 3 December during 2010–2011 and 2011–2012 cropping seasons, respectively. The results showed that wheat cultivar Shafaq-06 produced more phenolic compounds at all density levels of littleseed canarygrass during both years, which caused more inhibition of littleseed canarygrass growth. More suppressive advantage of cultivar Shafaq-06 against littleseed canarygrass was responsible for its better morphological and yield related traits, and grain yield than cultivars Faisalabad-08 and Sehar-06. Among the tested cultivars, cultivar Sehar-06 had minimum allelopathic potential in suppressing littleseed canarygrass. In crux, Shafaq-06 possesses allelopathic potential to suppress littleseed canarygrass and may be used for breeding future wheat cultivars with high allelopathic activity for better weed suppression.     

Phosphorus-Mobilizing Rhizobacterial Strain Bacillus cereus GS6 Improves Symbiotic Efficiency of Soybean on an Aridisol Amended with Phosphorus-Enriched Compost

Legume plants are an essential component of sustainable farming systems. Phosphorus (P) deficiency is a significant constraint for legume production, especially in nutrient-poor soils of arid and semi-arid regions. In the present study, we conducted a pot experiment to evaluate the effects of a phosphorus-mobilizing plant-growth promoting rhizobacterial strain Bacillus cereus GS6, either alone or combined with phosphate-enriched compost (PEC) on the symbiotic (nodulation-N₂ fixation) performance of soybean (Glycine max (L.) Merr.) on an Aridisol. The PEC was produced by composting food waste with addition of single super phosphate. The bacterial strain B. cereus GS6 showed considerable potential for P solubilization and mobilization by releasing carboxylates in insoluble P (rock phosphate)-enriched medium. Inoculation of B. cereus GS6 in combination with PEC application significantly improved nodulation and nodule N₂ fixation efficiency. Compared to the control (without B. cereus GS6 and PEC), the combined application of B. cereus GS6 with PEC resulted in significantly higher accumulation of nitrogen (N), P, and potassium (K) in grain, shoot, and nodule. The N:P and P:K ratios in nodules were significantly altered by the application of PEC and B. cereus GS6, which reflected the important roles of P and K in symbiotic performance of soybean. The combined application of PEC and B. cereus GS6 also significantly increased the soil dehydrogenase and phosphomonoesterase activities, as well as the soil available N, P, and K contents. Significant positive relationships were found between soil organic carbon (C) content, dehydrogenase and phosphomonoesterase activities, and available N, P, and K contents. This study suggests that inoculation of P-mobilizing rhizobacteria, such as B. cereus GS6, in combination with PEC application might enhance legume productivity by improving nodulation and nodule N₂ fixation efficiency.     

Shift in physiological and biochemical processes in wheat supplied with zinc and potassium under saline condition

Soil salinity is a serious abiotic factor affecting the production of crops by reducing potassium (K) uptake due to strong competition with sodium (Na) cations in the root regions. In calcareous soils, most of the nutrients precipitate in unavailable forms for plants. This study investigated the physiological and biochemical response of two wheat genotypes salt tolerant Abadghar and salt sensitive Pari-73 supplemented with K and zinc (Zn) nutrition. A factorial experiment with three levels of K (0, 50 and 100 kg ha^?1) and three levels of Zn (0, 25 and 50 kg ha^?1) based on a complete randomized design was employed. The results showed significant effect of treatments on chlorophyll (Chl) contents, water relations, nitrogen metabolism and yield attributes. The treatment K+Zn (100, 25 kg ha^?1) was the most effective in increasing grain yield. The results achieved highlight the importance of K and Zn nutrition in salt-stress conditions.     

Two new diterpenoids from Salvia triloba

Two new diterpenoids, trilobic acid (1) and trilobiol (2), have been isolated from the methanolic extract of Salvia triloba. Their structures were elucidated with the aid of NMR spectroscopy including two-dimensional-NMR techniques.     

An artificial neural network model for estimating Mentha crop biomass yield using Landsat 8 OLI

Yield forecasting is essential for management of the food and agriculture economic growth of a country. Artificial Neural Network (ANN) based models have been used widely to make precise and realistic forecasts, especially for the nonlinear and complicated problems like crop yield prediction, biomass change detection and crop evapo-transpiration examination. In the present study, various parameters viz. spectral bands of Landsat 8 OLI (Operational Land Imager) satellite data and derived spectral indices along with field inventory data were evaluated for Mentha crop biomass estimation using ANN technique of Multilayer Perceptron. The estimated biomass showed a good relationship (R²?=?0.762 and root mean square error (RMSE)?=?2.74 t/ha) with field-measured biomass.

     

Impact of inland waters on highly pathogenic avian influenza outbreaks in neighboring poultry farms in South Korea

BackgroundSince 2003, the H5 highly pathogenic avian influenza (HPAI) subtype has caused massive economic losses in the poultry industry in South Korea. The role of inland water bodies in avian influenza (AI) outbreaks has not been investigated. Identifying water bodies that facilitate risk pathways leading to the incursion of the HPAI virus (HPAIV) into poultry farms is essential for implementing specific precautionary measures to prevent viral transmission.ObjectivesThis matched case-control study (1:4) examined whether inland waters were associated with a higher risk of AI outbreaks in the neighboring poultry farms.MethodsRivers, irrigation canals, lakes, and ponds were considered inland water bodies. The cases and controls were chosen based on the matching criteria. The nearest possible farms located within a radius of 3 km of the case farms were chosen as the control farms. The poultry farms were selected randomly, and two HPAI epidemics (H5N8 [2014–2016] and H5N6 [2016–2017]) were studied. Conditional logistic regression analysis was applied.ResultsStatistical analysis revealed that inland waters near poultry farms were significant risk factors for AI outbreaks. The study speculated that freely wandering wild waterfowl and small animals contaminate areas surrounding poultry farms.ConclusionsPet birds and animals raised alongside poultry birds on farm premises may wander easily to nearby waters, potentially increasing the risk of AI infection in poultry farms. Mechanical transmission of the AI virus occurs when poultry farm workers or visitors come into contact with infected water bodies or their surroundings. To prevent AI outbreaks in the future, poultry farms should adopt strict precautions to avoid contact with nearby water bodies and their surroundings.     

Identification of two anthocyanidin reductase genes and three red-brown soybean accessions with reduced anthocyanidin reductase 1 mRNA, activity, and seed coat proanthocyanidin amounts

Anthocyanidin reductase (ANR; EC 1.3.1.77) catalyzes a key step in the biosynthesis of proanthocyanidins (PAs; also known as condensed tannins), flavonoid metabolites responsible for the brown pigmentation of seeds. Here, two ANR genes (ANR1 and ANR2) from the seed coat of brown soybean (Glycine max (L.) Merr.) have been isolated and their enzymatic function confirmed for the reduction of cyanidin to (-)-epicatechin in vitro. Biochemical and genetic comparisons of soybean lines differing in seed coat color revealed three red-brown lines to exhibit major reductions in the amounts of soluble PAs in the seed coat compared to brown soybean lines. Two spontaneous mutants with red-brown grain color had reduced ANR1 gene expression in the seed coat, and an EMS-mutagenized red-brown mutant had nonsynonymous substitutions that resulted in slightly reduced ANR1 activity in vitro. These results suggest that defects in the ANR1 gene can be associated with red-brown soybean grain color. These results suggest that suppressing ANR1 gene expression or activity may be a rational approach toward engineering seed coat color to enable the visual identification of genetically modified soybean grains.     

Impact of tillage and nitrogen on cotton yield and quality in a wheat-cotton system,Pakistan

Growing cotton (Gossypium hirsutum L.) after wheat (Triticum aestivum L.) is an important cropping system in Pakistan. However, numerous tillage practices commonly applied for cotton production are not productive. Conservation tillage may optimize cotton yield and quality if nitrogen (N) is not a limiting factor. Field experiments were conducted on silty clay soil (Hyperthermic, and Typic Torrifluvents) of Dera Ismail Khan, Pakistan to study the impact of tillage techniques (zero (ZT), reduced (RT), and conventional tillage (CT)) and nitrogen, namely 0, 50, 100, 150, and 200 kg ha^–1 on cotton yield and quality. Mean values for N revealed that bolls plant^–1, boll weight, seed cotton yield, ginning out turn (GOT), fiber length, strength, and micronaire were highest at 150–200 kg N ha^–1. Averaged over years, tillage × nitrogen revealed that RT had higher bolls plant^–1, boll weight, GOT, fiber length, and strength at 150–200 kg N ha^–1 compared to other tillage system. The micronaire revealed that RT had no adverse effect on fiber fineness compared to ZT/CT. RT had accumulated higher soil organic matter and total soil N compared to CT. RT with 150–200 kg N ha^–1 may be a sustainable and environmentally safe strategy to enhance cotton yield and quality.     

Foliar feeding of boron improves the productivity of cotton cultivars with enhanced boll retention percentage

Abstract

Cotton (Gossypium hirsutum L.) is of prime importance because of its quality fiber and edible oil production. Boron (B) is among essential micronutrients for plant growth; it aids in the transfer of sugars and nutrients from leaves to fruit that are involved directly or indirectly in many plant functions. Cotton growth, yield and quality are strongly affected with boron application. A two-year study was conducted to evaluate the impact of foliar applied B (0, 2, 4, 6, 8 and 10?g of B L^?1 of water) on the performance of cotton cultivars (FH-113, MNH-786 and CIM-496). The results indicated that growth, yield and quality traits of cotton were significantly influenced by different levels of foliar applied boron as well as cultivars of cotton. Among cotton cultivars, the yield and quality parameters were superior in cultivar “FH-113.” Foliar application of boron at 6?g L^?1 of water improved leaf area index and leaf area duration and eventually improved the number of bolls per plant, boll retention percentage, average boll weight, lint yield, ginning out turn, fiber length and uniformity ratio of cotton. Foliar application of B at 6?g per liter of water, showed promising results by improving growth and quality parameters and is recommend to enhance the economical yield production of cotton cultivar “FH-113” with improved quality.     

Improving the Drought Tolerance in Rice (Oryza sativa L.) by Exogenous Application of Salicylic Acid

Drought stress encumbers the rice growth predominantly by oxidative damage to biological membranes and disturbed tissue water status. In this study, the role of salicylic acid (SA) to induce drought tolerance in aromatic fine grain rice cultivar Basmati 2000 was evaluated. SA was applied as seed and foliar treatments. For seed treatment, rice seeds were soaked in 50, 100 and 150 mg l⁻¹ aerated solution of SA for 48 h and then dried back. Treated and untreated seeds were sown in plastic pots in a phytotron. At four leaf stage, one set of plants was subjected to drought stress, while the other remained well watered. Drought was maintained at 50 % of field capacity by watering every alternate day. For exogenous application, SA was applied 50, 100 and 150 mg l⁻¹ at five leaf stage. In the control, SA was neither applied exogenously nor as seed treatment. Drought stress severely affected the seedling fresh and dry weight, photosynthesis, stomatal conductance, plant water relations and starch metabolism; however, SA application improved the performance of rice under both normal and stress conditions. Drought tolerance in rice was well associated with the accumulation of compatible solutes, maintenance of tissue water potential and enhanced potency of antioxidant system, which improved the integrity of cellular membranes and facilitated the rice plant to sustain photosynthesis and general metabolism. Foliar treatments were more effective than the seed treatments. Foliar application with 100 mg l⁻¹ (FA 100) was the best treatment to induce the drought tolerance and improve the performance under normal and stress conditions compared with the control or other treatments used in this study.