Water scarcity is threatening the sustainability of global food grain production systems. Devising management strategies and identification of crop species and genotypes are direly required to meet the global food demands with limited supply. This study, consisted of two independent experiments, was conducted to compare faba bean (Vicia faba L.) genotypes Giza Blanka, Goff‐1, Hassawi‐1, Hassawi‐2 and Gazira‐2 in terms of physiological attributes and yield under water‐limited environments. In first experiment, conducted in a growth chamber, osmotic stress of −0.78, −0.96, −1.19 and −1.65 MPa was induced using polyethylene glycol for 4 weeks. In second experiment, conducted in open field for two consecutive growing seasons, water deficit treatments were applied 3 weeks after sowing. In this experiment, irrigation was applied when an amount of evaporated water from the ‘class A pan’ evaporation reached 50 mm (well watered), 100 mm (moderate drought) and 150 mm (severe drought). Water deficit, applied in terms of osmotic stress or drought, reduced the root and shoot length, related leaf water contents, total chlorophyll contents and efficiency of photosystem‐II, plant height, grain yield and related attributes in faba bean; increased the leaf free proline, leaf soluble proteins and malondialdehyde contents, and triggered the maturity in tested faba bean genotypes. However, substantial genetic variation was observed in the tested genotypes in this regard. For instance, root length of genotypes Giza Blanka and Hassawi‐2 decreased gradually, whereas it was increased in genotypes Goff‐1, Hassawi‐1 and Gazira‐2 with increase in the level of osmotic stress. Genotypes Gazira‐2 and Hassawi‐2 had better relative leaf water contents, leaf free proline and soluble proteins under water deficit conditions; however, these were minimum in genotype Giza Blanka. Better accumulation of leaf free proline, soluble proteins, and maintenance of chlorophyll contents, tissue water, efficiency of photosystem‐II and grain weight in water‐limited conditions helped some genotypes like Hassawi‐2 to yield better. Future breeding programs for developing new faba bean genotypes for water‐limited environments may consider these traits.

Agricultural activities emit greenhouse gases (GHGs) and contribute to global warming. Intensive plough tillage (PT), use of agricultural chemicals and the burning of crop residues are major farm activities emitting GHGs. Intensive PT also degrades soil properties by reducing soil organic carbon (SOC) pool. In this scenario, adoption of no‐till (NT) systems offers a pragmatic option to improve soil properties and reduce GHG emission. We evaluated the impacts of tillage systems (NT and PT) and wheat residue mulch on soil properties and GHG emission. This experiment was started in 1989 on a Crosby silt loam soil at Waterman Farm, The Ohio State University, Columbus, Ohio, USA. Mulching reduced soil bulk density and improved total soil porosity. More total carbon (16.16 g kg−1), SOC (8.36 mg L−1) and soil microbial biomass carbon (152 µg g−1) were recorded in soil under NT than PT. Mulch application also decreased soil temperature (0–5 cm) and penetration resistance (0–60 cm). Adoption of long‐term NT reduced the GHG emission. Average fluxes of GHGs under NT were 1.84 g CO2‐C m−2 day−1 for carbon dioxide, 0.07 mg CH4‐C m−2 day−1 for methane and 0.73 mg N2O‐N m−2 day−1 for nitrous oxide compared with 2.05 g CO2‐C m−2 day−1, 0.74 mg CH4‐C m−2 day−1 and 1.41 mg N2O‐N m−2 day−1, respectively, for PT. Emission of nitrous oxide was substantially increased by mulch application. In conclusion, long‐term NT reduced the GHG emission by improving the soil properties. Copyright © 2016 John Wiley & Sons, Ltd.

The increasing range of Aedes albopictus, the Asian tiger mosquito, in the USA and the threat of chikungunya and dengue outbreaks vectored by this species have necessitated novel approaches to control this peridomestic mosquito. Conventional methods such as adulticiding provide temporary relief, but fail to manage this pest on a sustained basis. We explored the use of cold aerosol foggers and misting machines for area-wide applications of Bacillus thuringiensis var. israelensis (VectoBac WDG) as a larvicide targeting Aedes albopictus. During 2010–2013 we performed initially open field trials and then 19 operational area-wide applications in urban and suburban residential areas in northeastern USA to test three truck-mounted sprayers at two application rates. Area-wide applications of WDG in open field conditions at 400 and 800 g/ha killed on average 87% of tested larvae. Once techniques were optimized in residential areas, applications with a Buffalo Turbine Mist Sprayer at a rate of 800 g/ha, the best combination, consistently provided over 90% mortality. Importantly, there was no significant decrease in efficacy with distance from the spray line even in blocks of row homes with trees and bushes in the backyards. Under laboratory conditions Bti deposition in bioassay cups during the operational trials resulted in over 6 weeks of residual control. Our results demonstrate that area-wide truck mounted applications of WDG can effectively suppress Ae. albopictus larvae and should be used in integrated mosquito management approaches to control this nuisance pest and disease vector.

The diamondback moth, Plutella xylostella, is recognized as a widely distributed destructive insect pest of Brassica worldwide. The management of this pest is a serious issue, and an estimated annual cost of its management has reached approximately US$4 billion. Despite the fact that chemicals are a serious threat to the environment, lots of chemicals are applied for controlling various insect pests especially P. xylostella. An overreliance on chemical control has not only led to the evolution of resistance to insecticides and to a reduction of natural enemies but also has polluted various components of water, air, and soil ecosystem. In the present scenario, there is a need to implement an environmentally friendly integrated pest management (IPM) approach with new management tactics (microbial control, biological control, cultural control, mating disruption, insecticide rotation strategies, and plant resistance) for an alternative to chemical control. The IPM approach is not only economically beneficial but also reduces the environmental and health risks. The present review synthesizes published information on the insecticide resistance against P. xylostella and emphasizes on adopting an alternative environmentally friendly IPM approach for controlling P. xylostella in China.

Life table and predation data were collected for Coccinella septempunctata (Linnaeus) (Coleoptera: Coccinellidae) feeding on three different host aphid species, Aphis craccivora (Koch) (Hemiptera: Aphididae), Lipaphis erysimi (Kaltenbach) (Hemiptera: Aphididae), and Myzus persicae (Sulzer) (Hemiptera: Aphididae), under laboratory conditions, using age-stage, two-sex life table. The preadult developmental period of C. septempunctata was the shortest on M. persicae (21.12 d) and the longest on A. craccivora (28.81 d). Net reproductive rate (R0) ranged from 77.31 offspring per individual on A. craccivora to 165.97 offspring per individual on M. persicae. Mean generation time (T) ranged from 39.10 d on M. persicae to 51.96 d on L. erysimi. Values of the intrinsic rate of increase (r) decreased in the order M. persicae, A. craccivora, and L. erysimi (0.1302, 0.0864 and 0.0848 d-1, respectively). The highest finite rate of increase (λ) was observed on M. persicae (1.1391 d-1) and the lowest was observed on A. craccivora and L. erysimi (1.0903 and 1.0885 d-1, respectively). This information will be useful in relation to the mass rearing of C. septempunctata in biological control systems.

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Production of phosphorus efficient crop cultivars can increase food productivity and decrease environmental pollution. Categorization of existing germplasm is a prerequisite to develop P efficient crop cultivars. For first experiment, 30 wheat genotypes were grown in hydroponics with two P levels (i.e., deficit, 20 μm KH2PO4 and adequate, 200 μm KH2PO4). Genotypes differed significantly for various P efficiency parameters. Two genotypes (Dirk and Bhakkar-02) showed < 25% decrease in growth at P deficiency. Genotype Seher-06 proved to be inefficient. Twelve selected genotypes based on the first experiment were sown in soil with two P levels (0 and 30 mg P kg-1) till maturity. As expected, genotypes differed for grain yield at both P levels. The efficient cultivars selected on the basis of both absolute and relative dry matter production at both P levels such as Dirk. Genotypes were grouped into three, four and nine classes on the basis of various parameters for P efficiency as proposed by different researchers. Most genotypes behaved in a similar fashion by different categorization methods and also at different P supply. The method to categorize the genotypes into three classes and plotting them into 9 classes proposed by Gill and his coworkers, is the best to differentiate the minor differences in genotypes. At least three different parameters at both P regimes should be used. The parameters may vary as per objectives of the study and/or growth conditions.

Seedling emergence and stand establishment of crops following the allelopathic crops are often affected. When the crops are grown in rotation, they are influenced by allelopathy of preceding crop. In this study, consisting of three independent experiments, allelopathic effect of tobacco, rich in several allelochemicals, on the subsequent maize and mungbean crops was investigated. In first experiment, maize and mungbean were sown in field previously occupied by tobacco or was fallow. In second experiment, maize and mungbean were planted in pots after the harvest of tobacco. Whereas in third experiment, maize and mungbean seeds were soaked in water or 2 and 4 mM nicotine and were then sown in soil-filled pots. Stand establishment, leaf emergence and growth of maize were significantly improved when grown after tobacco, whereas in mungbean these characters were suppressed when grown after tobacco. Likewise external application of nicotine improved the emergence uniformity, seedling dry weight and chlorophyll contents in maize and suppressed these parameters in mungbean. Tobacco allelopathy also increased the total soil nitrogen, zinc, iron, nicotine and total phenolics. Nicotine-induced change in chlorophyll contents and α-amylase activity seems the possible reason of differential response of maize and mungbean to tobacco allelopathy. When grown in rotation with tobacco, stand establishment and growth of maize were improved, whereas mungbean stand and growth were suppressed. In crux, allelopathic nature of the crops must be considered while making the crop rotations.