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The research was carried out to determine the effect of Populus deltoides trees on the soil physical and chemical properties and grain yield of wheat crop under the agro ecological conditions of Faisalabad (Punjab), Pakistan. Two fields were selected; one with wheat monoculture and the other had boundary trees of Populus deltoides. The average age of the s Populus trees was 5 years. Number of trees was 40 per acre. The average height and diameter at breast height of trees was 12 meters and 42.43 cm respectively. The wheat crop was sown in October, 2020 in both fields and harvested in April, 2021. A quadrate of one meter square was used to collect the data. The quadrate was put at various distances (2-24 meter) from tree stems and the plants growing there were harvested. The grain yield (gm-2) per quadrate was determined with the help of an electric weighing balance. The soil samples were selected from both fields and various chemical and physical properties of soil were determined. The soil pH was 7.32 and 7.95 in wheat monoculture and Populus+wheat field respectively. Total nitrogen was 0.05 and 0.08%in both fields respectively as mentioned above. Organic matter was 0.64 and 0.81 in wheat monoculture and Populus based field respectively. The effect of Populus trees on grain yield of wheat was negative form 2m to 10 meter distance from trees. While from 12m to 24 m distance, wheat grain yield was more or less equal in both fields i.e. with and without trees. Net income was Rs. 67437.69 and Rs. 104781.03 per acre without and with trees, respectively. On the basis of this research, it is concluded that wheat + Poplar is more suitable option for farmers. So farmers should adopt this system to generate more money while keeping the inputs same.

The economic rotation of two different tree species was calculated during 2020 in two different tehsils (sub-districts) namely Gujranwala and Khushab which are located in Punjab province of Pakistan. Vachellia is a common tree grown on the farmlands of Gujranwala while Eucalyptus is a common tree growing on the farmlands of Khushab. So that these two tree species were selected from two different tehsils of Punjab. Vachellia is grown at a rotation of 10 to 20 years while Eucalyptus is grown on 5 to 12 years rotation. For the evaluation of economic rotation of both tree species, net present worth and benefit cost ratio was calculated. 300 trees of both tree species were randomly selected from their respective tehsils. Different rotations of Eucalyptus were tested viz., 12 years rotation, 6 + 6 = 12 years, 8 + 4= 12 years and 4 + 8 = 12 years, while the total span (12 years) was kept same in all rotations. The total span was kept at 12 years because this tree is grown at a maximum rotation of 12 years on the farmlands. Similarly, different rotations were tested in case of Vachellianilotica viz., 10 years, 5 + 5 = 10 years and 6 + 4 = 10 years with the same total span of 10 years. In case of Eucalyptus, net present worth was found to be Rs. 4035.525, 4506.45, 4310.375 and 4379.175 at a rotation of 12, 6+6 = 12, 8+4=12 and 4+8 = 12 years, respectively. However, best rotation was found to be 6 + 6 = 12 years with highest net present worth. Similarly in case of Vachellia, net present worth was found to be Rs. 4844.532, 5155 and 5675.322 at a rotation of 10 years, 5 + 5 = 10 years and 6 + 4 = 10 years, respectively. rotation of 6 + 4 = 10 years was found to be best. It is recommended that farmers of Khushab should grow Eucalyptus trees at a rotation of 6 + 6 = 12 years. The farmers of Gujranwala are recommended to raise Vachellia trees on a rotation of six years followed by another short rotation of 4 years for more financial benefits.

The present work aimed to develop and investigate microbial consortia for petroleum hydrocarbons (PHCs) detoxification and plant growth improvement in hydrocarbons-contaminated soil. Here, we isolated several bacteria from PHCs-contaminated soils to make bacterial consortia and two of the best consortia were tested in a pot experiment to evaluate their potential for PHCs removal and chickpea growth promotion in PHCs-contaminated soil. Results demonstrated that the PHCs exerted considerable phytotoxic effects on chickpea growth and physiology by causing a 13–29% and a 12–43% reduction in agronomic and physiological traits, respectively. However, in the presence of bacterial consortia, the phytotoxicity of PHCs to chickpea plants was minimized, resulting in a 7.0–24% and a 6.0–35% increase in agronomic and physiological traits, respectively over un-inoculated controls. Bacterial consortia also boosted nutrient uptake and the antioxidant mechanism of the chickpea. In addition, chickpea plants alone phytoremediated 52% of initial PHCs concentration. The addition of bacterial consortia in the presence of chickpea plants could remove 74–80% of the initial PHCs concentration in soil. Based on our research findings, we suggest that the use of multi-trait bacterial consortia could be a sustainable and environmentally friendly strategy for PHCs remediation and plant growth promotion in hydrocarbons in contaminated soil.

The relationship between ethylene and cyanide (HCN) and karrikin 1 (KAR1) in dormancy release was studied in secondary dormant Brassica oleracea L. (Chinese cabbage) seeds. Freshly harvested seeds of Brassica oleracea usually have poor germination potential. Karrikin1 (KAR1) and cyanide (HCN) are able to stimulate seed germination. However, the stimulatory effects of these two chemicals depend on the activation of the ethylene biosynthesis pathway and on ethylene perception. In this study, KAR1 and HCN application increased the activity of ethylene and of two ethylene biosynthesis enzymes, ACC synthase (ACS) and ACC oxidase (ACO). KAR1 and HCN collectively promoted the accumulation of 1 aminocyclopropane-1-carboxylic acid (ACC). In the presence of NO (nitric oxide) and KAR1, ACS and ACO activities reached their maximum levels after 36 and 42 h, respectively. Ethylene inhibitors suppressed seed germination by approximately 55%, whereas the respiratory inhibitors SHAM and NaN3 inhibited seed germination by 5–10% in the presence of HCN and KAR1. KAR1 and HCN collectively reduced the abscisic acid (ABA) content in seeds, increased the gibberellic acid (GA) content and released seed dormancy. The expression of ethylene biosynthesis genes and ethylene receptor genes (BOACO1, BOACS1, BOACS3, BOACS4, BOACS5, BOACS7, BOACS9, BOACS11, BOETR1 and BOETR2) provided further evidence of the involvement of ethylene in KAR1 and HCN-induced germination. BOACO1, BOACS1, BOACS5, BOACS7, BOACS9, BOACS11, BOETR1 and BOETR2 genes were up regulated in the presence of KAR1 and HCN, while the remaining genes were down regulated. The expression of various ethylene biosynthesis and ethylene receptor genes suggested functional diversification and variations in seed sensitivity in the presence of KAR1 and HCN. Therefore, in the current study, KAR1 and HCN application effectively induced the germination of B. oleracea seeds (approximately 97% germination rate) after 6 days by modifying the ethylene biosynthetic pathway.

Salinity is a widespread soil and underground water contaminant threatening food security and economic stability. Phytoremediation is an efficient and environmental-friendly solution to mitigate salinity impacts. The present study was conducted to evaluate the phytoremediation potential of five multipurpose trees

Wastewater used as irrigation water is causing heavy metal accumulation in the agro-ecosystems. A greenhouse study was conducted to compare the phytoaccumulation ability of four agroforestry tree species under different wastewater treatments. Three-month-old potted seedlings of Morus alba, Acacia nilotica, Acacia ampliceps, and Azadirachta indica were irrigation with tap water (C), municipal wastewater (MWW), and industrial wastewater (IWW). Results showed that MWW had a positive and IWW had a negative impact on biomass production in all the species. Acacia ampliceps showed the highest increment (65%) and showed the lowest decrease (5%) in total biomass under both MWW and IWW treatment. Pb concentration was also found highest in the leaves, stem and roots of Azadirachta indica (108.5, 46.2, 180.5 mg kg−1, respectively) under IWW. Production of H2O2 was highest in IWW treatment with almost 148% increase observed in Azadirachta indica. Similarly, the production of antioxidative enzymes (Superoxide dismutase, Catalase and Peroxidase) was also highest in Azadirachta indica under IWW. Therefore, results suggest that along with high increment in total biomass, both Acacia ampliceps and Azadirachta indica showed high Pb concentration and an effective antioxidative defense mechanism and thus, can be used for planting in soils irrigated with MWW and IWW.

Farm friendly and fast growing trees are the sustainable, cheaper and efficient source of carbon sequestration and carbon stock, however, their carbon sequestration potential vary among tree species depending upon several factors. This study was conducted to determine the carbon sequestration potential and carbon storage difference among different tree species at early stage. Second objective of this study was to observe the effects of trees on the physico-chemical properties of soils. Seedlings of fifteen widely planted farm trees species were planted under same set of climatic and soil conditions. Employing tree biomass after two year of planting (2014-2016), carbon stocks and carbon sequestration rates were calculated. Soil samples were collected under each tree species at two depths: 0-15cm and 16-30 cm, to determine the physico-chemical properties of soils such as pH, EC, N, P, K, C and organic matter (O.M.). It was found that Populus deltoides contained the highest carbon stocks (7.21 ± 1.31 kg C) and sequestered the CO2 at the highest rate of 13.21 ± 0.84 kg C/year as compared to all other fourteen tree species. O.M. (%) and Carbon (mg/kg) were also the highest in the soils under P. deltoides (2.29 ± 0.42 and 3.8 ± 0.2 respectively) as compared to and all other tree species. Nitrogen contents (%) were found the maximum in the soils under D. sissoo (0.063 ± 0.04) > Acacia nilotica (0.058 ± 0.008) and Albizia lebbeck (similar to Acacia nilotica). Such information enhances our capacity to better predict the carbon sequestration potential and carbon stock in different trees.

Lead (Pb) is one of the most toxic and persistent elements, with no known biological role. High concentrations of lead enter saline soils through anthropogenic activities and industrial waste. The decontamination of Pb polluted sites through phytoremediation, especially by using woody plants, is an attractive approach. Eucalyptus camaldulensis is a good accumulator of Pb and a recommended tree species for reclamation of saline soils. However, there is very limited knowledge about the Pb-uptake behavior of Eucalyptus camaldulensis under saline conditions. The objective of this study was to examine the simultaneous impact of NaCl salinity and Pb stress on the phytoremedial potential and growth behavior of E. Camaldulensis. Six-week-old Eucalyptus camaldulensis plants with uniform morphological features were transferred into hydroponic conditions, and they were exposed to the NaCl salinity stress at 200 mM and Pb stress at 10 mg L-1 and 20 mg L-1 (Pb1 and Pb2, respectively). The plants showed a 100% survival rate in all treatments. All the morphological parameters (plant height, plant diameter, and shoot dry weight) for E. Camaldulensis were significantly affected when exposed to Pb or Pb + NaCl-salinity, with the exception of root length which was 36% higher in Pb2 as compared to the control. The Pb uptake (mg Pb plant-1) was much higher (49.3) under Pb2 + NaCl-salinity, as compared to the control (1.2) and other treatments, which shows that saline conditions increased the Pb-uptake in E. Camaldulensis. The order of deposition of Pb (mg Pb kg-1 of dry weight) in plant parts was root (103.4) >> shoot (17.5) > leaves (13.6). Similarly, the bioconcentration factor (BCF) of the roots was 4 to 6 times higher than shoot BCF.

International audience; Lowland rice crop is cultivated under continuous flooding and anaerobic conditions but rhizospheric region of the rice plants can have different physico-chemical conditions than in the absence of roots. However, it is very difficult to measure all physico-chemical parameters instantaneously in the rhizosphere because this region, being highly dynamic, altering rapidly those parameters of surrounding soil waters. Present study has compared the evolution of electro-physico-chemical properties (pH, redox potentials (pe), Electrical Conductivity (EC) and temperature) of soil waters during a complete day at two different phenological stages in the presence of rice roots (rhizosphere) and in the absence of roots to analyse the effect of rhizosphere on soil waters. In the rhizosphere, pH of soil waters was found comparatively low (7). Similarly, small EC values were observed in the rhizosphere. Great fluctuations (diurnal patterns) were observed during the complete days which were directly associated to atmospheric conditions (temperature and light) and rhizospheric activity, and these fluctuations were more during vegetative phase as compared to maturation stage of rice. It was also observed that incorporation of crop residues resulted in the more reductive conditions in the rice culture.