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In the Tibetan Plateau grassland ecosystems, nitrogen (N) availability is rising dramatically; however, the influence of higher N on the arbuscular mycorrhizal fungi (AMF) might impact on plant competitive interactions. Therefore, understanding the part played by AMF in the competition between Vicia faba and Brassica napus and its dependence on the N-addition status is necessary. To address this, a glasshouse experiment was conducted to examine whether the grassland AMF community's inocula (AMF and NAMF) and N-addition levels (N-0 and N-15) alter plant competition between V. faba and B. napus. Two harvests took day 45 (1st harvest) and day 90 (2nd harvest), respectively. The findings showed that compared to B. napus, AMF inoculation significantly improved the competitive potential of the V. faba. In the occurrence of AMF, V. faba was the strongest competitor being facilitated by B. napus in both harvests. While under N-15, AMF significantly enhanced tissue N:P ratio in B. napus mixed-culture at 1st harvest, the opposite trend was observed in 2nd harvest. The mycorrhizal growth dependency slightly negatively affected mixed-culture compared to monoculture under both N-addition treatments. The aggressivity index of AMF plants was higher than NAMF plants with both N-addition and harvests. Our observation highlights that mycorrhizal associations might facilitate host plant species in mixed-culture with non-host plant species. Additionally, interacting with N-addition, AMF could impact the competitive ability of the host plant not only directly but also indirectly, thereby changing the growth and nutrient uptake of competing plant species. [ABSTRACT FROM AUTHOR]

The present research study was conducted during 2009, 2012, 2013 and 2014 under National Cotton Varietal Trial (NCVT) for the expression profiling of Bt gene in local cotton genotypes/entries. Firstly, a total of 180 cotton lines (12, 75, 49 and 44 in years 2009, 2012, 2013 and 2014, respectively) were used to check the types of Bt gene(s) through immunostrip assay. Most of the entries were positive for the presence of Cry1Ac gene (Bollgard I) except CEMB-01 in 2009, DNH-105, BH-176 and CIM-573 (non Bt. Standard) in 2012, CIM-573 (non Bt. Standard) and CRIS-342 (non Bt. Standard) in 2013 and BH-185 and SLH-8 in 2014. Only a single entry (Kissan Early in 2012) was found positive for both Cry1Ac and Cry2Ab (Bollgard II). None of the entry gave positive result for Cry1F (Wide Strike event) through immunostrip assay. Later, expression level of Cry1Ac gene for all the entries were quantified through sandwich-ELISA. The expression level for twelve entries during 2009 was recorded in the range of 0.21-1.31μg/g of fresh weight leaf tissue. During 2012, the expression level for Cry1Ac was measured in the range of 0.05-0.86μg/g. All the positive entries for Cry1Ac gave the expression level less than as recommended by EPA-USA (>1.5μg/g). In 2013 and 2014, the expression level for Cry1Ac was quantified in the range of 0.03-4.17 and 0.04-4.29μg/g, respectively. Data of four years revealed that considerable gradual improvement has been made in the levels of Bt toxin in local candidate cotton lines at breeder level. There is need to sustain the attained toxin levels under farmer field conditions. [ABSTRACT FROM AUTHOR]

Establishment of an efficient and reproducible regeneration system in three different rice cultivars, IRRI-6, IRRI-9 and KSK-282 remained obscured. In the present study regeneration system was developed for all three recalcitrant cultivars and resultant putative transgenic plants were analyzed for expreöion by reverse transcriptase polymerase chain reaction (RT-PCR). Cultivars responded to a particular concentration of 2, 4-D ranging from 2 to 4mg L-1for calli initiation and induction. Two types of calli with different frequencies were observed on both N6 and N6 supplemented with proline, glycine and MES. N6 media produced more number of type II calli while N6 supplemented favored type I calli in all three cultivars. Type I calli were found as yellowish, smaller in size and globular shape and better explants for transformation. GUS histochemical aöay showed that 11, 13 and 14 days older type I calli of KSK-282, IRRI-6 and IRRI-9were suitable for transformation respectively. Fifteen minutes infection time and 2 days co-cultivation period showed the highest GUS positive expreöion in calli of all three cultivars. KSK-282 and IRRI-9 showed best regeneration response on 0.5 mg L-1 kinetin, 1 mg L-1NAA and 3 mg L-1 BAP, while the IRRI-6 showed the highest regeneration at 0.5 mg L-1 kinetin, 1mg L-1 NAA and 2 mg L-1 BAP. Using optimized protocol for each cultivar GUS reporter gene has been succeöfully incorporated in the genome of all three cultivars. Transgene expreöion in resultant lines was confirmed at transcriptional level through reverse transcriptase polymerase chain reaction (RT-PCR). © 2014 Friends Science Publishers [ABSTRACT FROM AUTHOR]

Expression of Bt gene in cotton is affected by various environmental factors. The objective of the current study was the detection and quantification of Bt endo-toxins in local Pakistani cotton genotypes in various plants under different salt stress levels in various plant parts. Detection of Bt gene type was performed by immune strip analysis while, quantification of Bt toxin was carried out by commercially available ELISA kits. Ten transgenic cotton genotypes of local origin were assessed for the detection of Cry1Ac, Cry1F and Cry2Ab genes. Immunostrip analysis for all Bt cotton genotypes revealed the presence of only Cry1Ac gene. PCR result confirmed the presence of only Mon531 (non-patented) event of 346 base pair amplicon size and ruled out the presence of any other patented event in Pakistani Bt cotton varieties. The toxin value show highly significant differences under different salt stress levels. Bt toxin values were inversely affected by the increase in salinity levels. Bt toxin values tend to decrease after 90 days of sowing in all treatments. Moreover, higher values on fresh weight basis were noted in leaf tissues followed by square tissues. [ABSTRACT FROM AUTHOR]

A green house study was conducted at the University of Malakand, NWFP, Pakistan to evaluate the effect of marble industry effluent on soil pH, germination, post germinative growth and productivity of maize. The experiment was conducted in triplicate form for each treatment and tape water was used as control (T0). Effluents were diluted with tap water at concentration of 20% (T1), 40% (T2), 60% (T3), 80% (T4) and also used 100% (T5) concentration in 4 kg soil pot(-1) and plants were grown for 90 days. Results showed that there was a linear increase in pH of soil with increase in effluent concentration while germination, root length and stem girth was enhanced and found maximum at 40% concentration of effluent applied. The shoot length and root dry biomass was depressed as compared to control. It is concluded from the present study that marble industry effluent can be used as a fertilizer in low concentration especially for highly acidic soil but there is still need to carry out series of greenhouse and field trials to ascertain the fertilizer potentials of this effluent for maize crop.