Salinity is a devastating problem of arid and semi-arid climatic regions with uneven salt accumulation which hinders growth and development of crops. The deleterious effects of salinity mainly depend on level and source of salinity. We hypothesized that types of sodium salt (NaCl and Na2SO4) might cause variable toxicity in maize (Zea mays L.) plants. The objective of the present study was to compare the effect of different types of sodium salt (NaCl and Na2SO4), each at EC 5 and 10 dS m–1 on growth, physiology and nutrient contents of maize plant grown in earthen pots under wire house conditions. Results revealed toxic effects of salt stress on seed germination, root and shoot growth and biomass. Maize physiology in terms of sub-stomatal CO2 index, chlorophyll and relative water contents, photosynthetic and transpiration rate also reduced under salt stress. Among the types of salt and levels of salinity, NaCl applied at the rate of 10 dS m–1 caused the highest reduction in seed germination, growth and physiology due to high accumulation of Na and Cl ions whereas low in K ion in maize plant tissues. Based on the findings, we do conclude that NaCl applied at the rate of 10 dS m–1 has more negative impact on maize growth and nutrient acquisition than Na2SO4 at same level of salinity.

Wheat aphid, Sitobion avenae (Fab.), is a serious pest of wheat crop across the world. The present study was conducted to evaluate the potentials of the water plant extracts of Azadirachta indica (neem) or Eucalyptus camaldulensis and the entomopathogenic fungi (EPF); Beauveria bassiana or Metarhizium anisopliae against the aphid species. After 5 days of applications, the combined mixture of B. bassiana and eucalyptus extract caused the maximum mortality rate (87%). While the combination of B. bassiana with neem extract showed the least rate (54%). Fecundity was negatively affected by the single and combined treatments of EPF and botanicals extracts. The lowest fecundity (7 nymphs per female) was recorded when the aphid was treated by the binary mixture of B. bassiana and eucalyptus extract. Correspondent maximum fecundity (29 nymphs per female) in 5 days was recorded in control treatment, while 23 nymphs were produced by a single female when treated with the binary mixture of B. bassiana and neem extract. The results indicated that EPF and botanical extracts (neem or eucalyptus) caused significant reduction in survival and fecundity of S. avenae. Therefore, they may be used as promising natural alternatives to synthetic insecticides against the wheat aphid species.

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Background The red flour beetle, Tribolium castaneum (Herbst) (Coleoptera: Tenebrionidae), is a serious pest of stored grain commodities worldwide which results in considerable losses to stored wheat, Triticum aestivum (Linn.). Main body The present laboratory bioassay was carried out to examine the efficiency of the fungus, Beauveria bassiana (Bals.) formulation (Racer TM), and Neem extract (NE), Eucalyptus extract (EE), and Tobacco extract (TE) against 3rd instar larvae of T. castaneum. The fungal formulation was applied at 0.3 × 108, 0.6 × 108, and 0.9 × 108 conidia kg−1 of the crushed wheat grains; as well, it was mixed separately with 5% concentrations of each plant extract under the laboratory conditions of 30 ± 2 °C and 65 ± 5% RH. Mortality rate of the tested larvae was enumerated after regular intervals of times. Mortality of the larvae increased at the highest combined concentrations of the fungal conidial formulation and the plant extracts rather than their single treatments. The highest mortality rate of the larvae (71.32%) was recorded at the highest concentration binary mixture of (Racer TM +NE), whereas relatively the lowest mortality rate (15.54%) was enumerated in the combined treatments of (Racer TM +NE). Furthermore, the highest separate concentration of B. bassiana (0.9 × 108 conidia/ml) persistently resulted in more larval mortality (32.68%) of 3rd instar larvae of T. castaneum than the plant extracts (7.52, 9.89, and 14.61%), respectively. A noticeably greater rate of mycosis and sporulation was counted in the larvae of the insect in separate treatments of B. bassiana than in its combined applications with the plant extracts. The highest mycosis (85.13%) and sporulation (160.12 conidia/ml) was detected in the treatment, where the lowest concentration of B. bassiana (0.3 × 108 conidia/ml) was used, alone. Conclusion Hence, it was concluded that integrated use of these two bio-pesticides plus the fungus can be helpful in the integrated pest management program of T. castaneum.

Organic amendments improve the soil quality and plant productivity as well as help in the establishment of introduced bacteria. The present study was conducted to evaluate the interactive impact of organic amendments and plant growth promoting rhizobacteria strain Alcaligenes sp. AZ9 to improve maize productivity and soil quality. organic amendments including rock phosphate enriched compost (RPEC), biochar, and humic acid were applied in soil along with and without Alcaligenes sp. AZ9. The results revealed that the sole application of organic amendments along with Alcaligenes sp. AZ9 showed increase in growth and grain yield of maize. However, a combined application of organic amendments (RPEC, biochar, and humic acid) along with Alcaligenes sp. AZ9 showed maximum increase in plant height up to 14%, shoot dry biomass up to 30%, 1000-grains weight up to 10%, grain yield up to 31%, stover yield up to 34%, and potassium (K) concentration in grains up to 12% as compared to absolute control. The increase in nitrogen (N) and phosphorus (P) concentration in grains was non-significant over control. This treatment also improved soil biological attributes in terms of the bacterial population up to 60%, microbial biomass carbon up to 22%, soil organic carbon up to 29%, and saturation percentage of soil up to 14% as compared to control. It can be concluded that the application of organic amendments improved establishment of introduced bacteria, which could be effective in improving maize growth and yield as well as soil health.