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Red sprangletop (Leptochloa chinensis L.) is a problematic weed of aerobic rice (Oryza sativa L.) that greatly reduces in yield. The laboratory studies were undertaken to confirm allelopathicity of its plant leachates and soil-decomposition plant residues towards emergence and seedling growth of rice. In first experiment, aqueous extracts from various plant parts of red sprangletop (stem, root, leaves, flower and entire plant) at their 5% (w/v) concentration were applied to germinating rice seeds. In second experiment, soil-decomposed red sprangletop plant residues of variable concentrations (2, 4 and 6% w/w) were used as germination media for rice. Among plant parts, red sprangletop leaves showed maximum allelopathic effect by fully inhibiting the germination of rice while its stem could be positioned at second situation as it caused 60, 73, 84.13 and 86 % reductions in germination percentage, germination index, seedling length and seedling dry biomass of rice as compared with control, respectively. This treatment also resulted in maximum delays in mean germination time (up to 4.80 days) and days taken to 50% germination (up to 4.40 days) of rice. The highest concentrated (6%) soil-decomposed plant residue of red sprangletop significantly diminished the germination percentage, germination index, seedling length and seedling vigor index that were 35.13, 23.26 and 41.61% lower than control. It very well may be presumed that liquid concentrates of leave and stem soil-decomposed plant residues of 6% concentration had different kind of allelochemicals that inhibited the germination, seedling growth and development of rice.

A trial was undertaken to ascertain the efficacy of lactofen keeping its full and minimized application rates on Rhynchosia capitata (Roth.) DC in green gram alone and in tank mixed addition of adjuvant (alkyl ether sulfate) at Research Area, University of Sargodha during spring 2015. The studies consisted of seven herbicide treatments, viz. lactofen complete dose (180 g a.i. ha-1) alone, lactofen complete dose + adjuvant, lactofen 80% dose alone, lactofen 80% dose + adjuvant, lactofen 60% dose alone, lactofen 60% dose + adjuvant and a control (no herbicide). It was found that lactofen full dose with and without adjuvant attained significantly the lowest R. capitata dry weight and highest seed yield of green gram. However, these treatments remained statistically at par with lactofen 80% and lactofen 60% doses with adjuvant regarding these parameters. Keeping in view the R. capitata weed control efficiency along with green gram yield enhancement, it was concluded that lactofen dose can be reduced up to 20-40% by the addition of adjuvant (alkyl ether sulfate) for management of R. capitata in green gram crop.

A half-root stress is a half portion of the root system exposed to treatment while the remaining half portion kept under normal conditions. A half-root stress including half-root drought stress, half-root nutrient stress, and half-root salinity stress has become a general approach to improve plant performance and adaptability. Plants produce some chemical signals in stressed part of root, and other parts sense these signals to improve the acclimation and adaptive responses to environmental stresses. Plants adapt the compensatory functions and discriminate the systemic and local regulatory mechanisms, but the understanding of these mechanisms is controversial. Chemical signals (Abscisic acid, sap pH, cytokinins, content of malate, amino acid, and ureide) have been involved in root to shoot signaling under half-root stress. Furthermore, naturally appeared half-root stress in intercropping systems could be an additional attribute of half-root stress approach. Therefore, much more study is required to elaborate its acceptability in intercropping. In this review, we summarized the current knowledge and identified some key future researches areas regarding half-root stress approach.

Broadleaf weeds constitute major proportion of weed flora in wheat. A field study to find out suitable herbicides for controlling broadleaf weeds in wheat crop was conducted during winter, 2014. Ten premixed herbicides viz., bromoxynil + MCPA at 450 g a.i. ha-1, fluroxypyr + clopyralid + tribenuron at 330 g a.i. ha-1, fluroxypyr + MCPA at 450 g a.i. ha-1, bromoxynil + MCPA + tribenuron methyl at 475 g a.i. ha-1, fluroxypyr + MCPA at 375 g a.i. ha-1, fluroxypyrmethyl + MCPA at 144 g a.i. ha-1, clopyralid at 525 g a.i. ha-1, tribenuron + fluroxypyr at 140 g a.i. ha-1, triasulfuron at 30 g a.i. ha-1 were applied 25 days after sowing (DAS) (1st irrigation). A weedy control was also kept for comparison. The highest weed control was given by bromoxynil + MCPA at 450 g a.i. ha-1, triasulfuron at 30 g a.i. ha-1, and fluroxypyr + MCPA at 450 g a.i. ha-1 as they gave highest values of weed control efficiencies (81.3, 81.2 and 79.7%) and herbicide efficiency indices (3.31, 3.27 and 3.25), respectively. Fluroxypyr + MCPA at 450 g a.i. ha-1 produced the highest grain yield (4.07 t ha-1) of wheat which was followed by triasulfuron at 30 g a.i. ha-1 (3.97 t ha-1) and bromoxynil + MCPA at 450 g a.i. ha-1 (3.95 t ha-1). The improvement in grain yield of wheat by herbicides seem to be resulted due to better weed control as grain yield showed significant negative relationship with total weed density (R2=0.68) and total weed biomass (R2=0.85). Regression analysis also revealed a significant positive dependence of grain yield on number of tillers m-2 (R2=0.93), spike length (R2=0.91), grains spike-1 (R2=0.83) and grain weight (R2=0.95). It is concluded that fluroxypyr + MCPA, triasulfuron and bromoxynil + MCPA are the best herbicides for the control of broadleaf weeds like Chenopodium album, Chenopodium murale, Convolvulus arvensis, Euphrobia helioscopia and Fumaria indica in wheat.

ABSTRACT Red sprangletop (Leptochloa chinensis L.) is a problematic weed of aerobic rice (Oryza sativa L.) that greatly reduces in yield. The laboratory studies were undertaken to confirm allelopathic potential of its plant leachates and soil-decomposition plant residues towards emergence and seedling growth of rice. In first experiment, aqueous extracts from various plant parts of red sprangletop (stem, root, leaves, flower and entire plant) at their 5% (w/v) concentration were applied to germinating rice seeds. In second experiment, soil-decomposed red sprangletop plant residues of variable concentrations (2, 4 and 6% w/w) were used as germination media for rice. Among plant parts, red sprangletop leaves showed maximum allelopathic effect by fully inhibiting the germination of rice while its stem could be positioned at second situation as it caused 60, 73, 84, 13 and 86% reductions in germination percentage, germination index, seedling length and seedling dry biomass of rice as compared with control, respectively. This treatment also resulted in maximum delays in mean germination time (up to 4.80 days with SE= 0.408) and days taken to 50% germination (up to 4.40 days with SE=0.431) of rice. The highest concentrated (6%) soil-decomposed plant residue of red sprangletop significantly reduced the germination percentage, germination index, seedling length and seedling vigor index by 35.13, 23.26 and 41.61% compared to control. It very well may be presumed that liquid concentrates of leave and stem soil-decomposed plant residues of 6% concentration had different kind of allelochemicals that inhibited the germination, seedling growth and development of rice.

The study was aimed to explore the phytotoxic potential of Sonchus oleraceus L. on the emergence and seedling growth of Echinocloa cruss-galli L. and quantification of allelochemicals present in leaves, stem and fruit of S. oleraceus weed. The experiment comprised of aqueous extracts of leaf, roots and fruits applied at 0.25, 0.5, 1, 2, 4 and 8% (w/v) along with a control (0%). Data regarding seed emergence, emergence index, emergence percentage, root length, shoot length and seedling dry weight was recorded. All the tested concentrations of all parts of S. oleraceus significantly inhibited the seed emergence, emergence index, emergence percentage (%) and growth and delayed mean emergence time and time taken to 50% emergence of E. cruss-galli weed. However, maximum mean emergence time (5.20 days) and time taken to 50% emergence (3.49 days), were noted at 8% concentration of fruit and leaf aqueous extract, respectively. Fruit aqueous extract at 8% concentration caused the lowest germination index (1.70), germination percentage (40%), root length (0.09 cm), shoot length (0.45 cm) and dry weight (0.16 g) of E. cruss-galli. Results suggested that the extract of S. oleraceus weed at concentration (8%) can be used as potential bio-herbicide for the control of E. cruss-galli weed.

ABSTRACT The study was aimed to explore the phytotoxic potential of Sonchus oleraceus L. on the emergence and seedling growth of Echinocloa cruss-galli L. and quantification of allelochemicals present in leaves, stem and fruit of S. oleraceus weed. The experiment comprised of aqueous extracts of leaf, roots and fruits applied at 0.25, 0.5, 1, 2, 4 and 8% (w/v) along with a control (0%). Data regarding seed emergence, emergence index, emergence percentage, root length, shoot length and seedling dry weight were recorded. All the tested concentrations of all the parts of S. oleraceus significantly inhibited the seed emergence, emergence index, emergence percentage (%), growth and delayed mean emergence time and time taken to 50% emergence of E. cruss-galli. However, maximum mean emergence time (5.20 days) and time taken to 50% emergence (3.49 days), were noted at 8% concentration of fruit and leaf aqueous extracts, respectively. Fruit aqueous extract at 8% concentration caused the lowest germination index (1.70), germination percentage (40%), root length (0.09 cm), shoot length (0.45 cm) and dry weight (0.16 g) of E. cruss-galli. Results suggested that the extract of S. oleraceus weed at concentration (8%) can be used as potential bio-herbicide for the control of E. cruss- galli weed.

Weed economic threshold in a specific crop serves as a tool for employing its cost-effective management. Studies were carried out to find out competitive effect of field bindweed (Convolvulus arvensis L.) on wheat at research area of College of Agriculture, University of Sargodha, Pakistan during winter season 2014-15. Experimental treatments included varying densities (0, 4, 8, 12, 16 and 20 plant m-2) of Convolvulus arvensis. The weed densities were maintained by thinning the excess weed seedlings one week after crop emergence. Wheat variety Galaxy was sown as a test crop. Results exhibited that increasing densities of C. arvensis increased its dry weight m-2 but reduced its plant height. A significant reduction in wheat growth and yield was recorded by increasing C. arvensis density. Wheat plant height, number of productive tillers, spike length and grain yield showed a significant decline at and beyond C. arvensis density of 8 plants per m2. Whereas number of grain spike-1 and 1000-grain weight of wheat were prone to substantial reduction at and above 4 and 12 C. arvensis plants m-2, respectively. Losses of grain yield of wheat ranged between 10 to 28% under the influence of C. arvensis density between 8 to 20 plants per m2. Economic threshold of C. arvensis as estimated by prediction model was 5.6 plants per m2 indicating that field bindweed weed in wheat should be controlled at this density.

This present study deals with the cross-linking of fungal β-glucosidase on Al 2 O 3 nanocrystals (NCs) synthesized in C. cajan for in-suit genistein production. The Cajanus cajan leaves were dried and used to prepare their extract at 65 °C by agitation for 30 min. For enzyme production under submerged culture, 50 mL of medium at pH 8.6 with an inoculum volume of 2 mL; was incubated for 72 h with optimized parameters at 30 °C. The Al 2 O 3 NCs were synthesized by adding 30 mM Al 2 NO 3 to 25 mL of leaf extract with NaOH at 65 °C for 50 min which enhanced the β-glucosidase specific activity when immobilized. Genistein by biotransformation was obtained using both free (0.67 ± 0.42 mg/mL) and Al 2 O 3 immobilized β-glucosidase (1.3 ± 0.66 mg/mL) for 48 h. The substrate level and enzyme concentration were 2.5 and 1 mL respectively. The UV visible spectra for leaf extract; free and cross-linked β-glucosidase and Al 2 O 3 NCs were at 225, 235, 300, and 210 nm. The bands for Al 2 O 3 NCs were achieved at 500–750 cm − 1 which showed the FTIR analysis to check the change in functional groups of free and Al 2 O 3 cross-linked β-glucosidase. In XRD analysis, peaks depicted the crystalline structure of Al 2 O 3 NCs ranging from 10–50°. The size of NCs was confirmed by using different magnifications (1.01, 2.00, 3.00, 5.00, 7.02, and 10 K X) of SEM images obtained. For zeta potential measurements, the peak was obtained at ˗21.0 mV.

A bacterial consortium BMP1/SDSC/01 consisting of six isolates was isolated from textile effected soil, sludge, and textile effluent from Hudiara drain near Nishat Mills Limited, Ferozepur Road, Lahore, Pakistan. It was selected because of being capable of degrading and detoxifying red, green, black, and yellow textile dyes. The pH and supplements were optimized to enhance the decolorization ability of the selected consortium. The results indicated that decolorizing ability of consortium for the red, green, black, and yellow dyes was higher as compared to individual strains. The consortium was able to decolorize 84%, 84%, 85%, 85%, and 82% of 200 ppm of red, green, black, yellow, and mixed dyes within 24 h while individual strain required 72 h. On supplementing urea, the consortium decolorized 87, 86, 89, 86, and 83%, respectively, while on supplementing sodium chloride the consortium decolorized 93, 94, 93, 94, and 89% of red, green, black, yellow, and mixed dyes, respectively, which was maximum while in the presence of ascorbic acid and ammonium chloride it showed intermediate results. The effect of untreated and treated dyes was investigated on Zea mays L. (maize) and Sorghum vulgare Pers. (sorghum). This study will help to promote an efficient biotreatment of textile effluents.