Expression profiling of transgenes (Cry1Ac and Cry2A) in cotton genotypes under different genetic backgrounds

Transgenic cotton carrying the CrylAc gene has revolutionized insect pest control since its adoption,although the development of resistance in insect pests has reduced its efficacy.After 10 years of cultivating Bacillus thuringiensis(Bt) cotton with a single Cry1 Ac gene,growers are on the verge of adopting Bt cotton that carries the double gene(Cry1 Ac+Cry2 A) due to its better effectiveness against insect pests.Thus,the current study was designed to evaluate the role of each gene in the effect...     

5‐Aminolevulinic Acid Activates Antioxidative Defence System and Seedling Growth in Brassica napus L. under Water‐Deficit Stress

The present study assesses the effects of 5‐aminolevulinic acid (ALA, 0, 0.1, 1 and 10 mg l^?1) on the growth of oilseed rape (Brassica napus L. cv. ZS758) seedlings under water‐deficit stress induced by polyethylene glycol (PEG 6000, 0 and ?0.3 MPa). Water‐deficit stress imposed negative effects on seedling growth by reducing shoot biomass, cotyledon water potential, chlorophyll content and non‐enzymatic antioxidants (glutathione and ascorbic acid) levels. On the other hand, water‐deficit stress enhanced the malondialdehyde (MDA) content, reactive oxygen species (ROS) production, enzymatic antioxidants activities, reduced/oxidized glutathione ratio (GSH/GSSG) and reduced/oxidized ascorbic acid (ASA/DHA) ratio in seedlings. Application of ALA at lower dosages (0.1 and 1 mg l^?1) improved shoot weight and chlorophyll contents, and decreased MDA in rape seedlings, whereas moderately higher dosage of ALA (10 mg l^?1) hampered the growth. The study also indicated that 1 mg l^?1 ALA improved chlorophyll content, but reduced MDA content and ROS production significantly under water‐deficit stress. Lower dosages of ALA (0.1 and 1 mg l^?1) also enhanced GSH/GSSG and ASA/DHA as compared to the seedlings under water‐deficit stress. The antioxidant enzymes (ascorbate peroxidase, peroxidase, catalase, glutathione reductase and superoxide dismutase) enhanced their activities remarkably with 1 mg l^?1 ALA treatment under water‐deficit stress. It was also revealed that 1 mg l^?1 ALA treatment alone induced the expression of APX, CAT and GR substantially and under water‐deficit stress conditions ALA treatment could induce the expression of POD, CAT and GR to a certain degree. These results indicated that 0.1–1 mg l^?1 ALA could enhance the water‐deficit stress tolerance of oilseed seedlings through improving the biomass accumulation, maintaining a relative high ratio of GSH/GSSG and ASA/DHA, enhancing the activities of the specific antioxidant enzymes and inducing the expression of the specific antioxidant enzyme genes.     

NUTRIENT UPTAKE,PHYSIOLOGICAL RESPONSES,AND YIELD ATTRIBUTES OF WHEAT (TRITICUM AESTIVUM L.) EXPOSED TO EARLY AND LATE DROUGHT STRESS

The response of different wheat cultivars to drought imposed after three and six weeks of seedling emergence was evaluated in the wire house. The seeds of recommended local wheat cultivars were sown in plastic pots. The drought stress decreased the water relation, nutrient uptake and grain yield of all the wheat cultivars. The early drought stress significantly reduced the nitrogen (N) uptake by 38% while late drought stress decreased nitrogen uptake by 46%. The phosphorus (P) and potassium (K) uptake were decreased by 49% and 37% under early drought stress, respectively while their uptake was decreased by 51% each under late drought stress. Grain yield was reduced by 24% under early drought stress while it was reduced by 60% under late drought stress. Water deficit at early growth stages reduced grain weight by 10% while it was reduced by 35% under water deficit at later stages of growth.     

Comparing mating designs to restore seed production of interspecific hybrids between Trifolium repens (white clover) and Trifolium uniflorum

Interspecific hybrids between Trifolium uniflorum and cultivated white clover (Trifolium repens) have highly useful characteristics for temperate pastoral systems derived from both parent species. However, the early hybrids (F₁ and BC₁) also have unacceptably poor seed production for commerce. This study analysed the basis for the poor seed production and investigated breeding strategies for overcoming the problem. The BC₁F₁ generation produced lower‐than‐expected numbers of heads per plant and seeds per floret. Backcrossing of selected hybrids to white clover corrected these deficiencies and created new variation. Seed numbers were also returned to near target levels by recurrent selection within the BC₁ generation. Thus, it was possible to retain a theoretical average of 25% of T. uniflorum genome and still achieve high seed production per plant. The BC₁F₂ and BC₂F₁ generations produced high seed numbers per plant, along with reasonable variation. Both of these second‐generation hybrid forms have high reproductive potential and should be the focus for the selection of the desired combinations of agronomic and seed production traits.     

Boron Induced Oxidative Stress,Antioxidant Defence Response and Changes in Artemisinin Content in Artemisia annua L.

Boron is an essential plant micronutrient and the range between deficient and toxic levels of boron is narrow for most of the plants. Like other elements, boron becomes toxic to growth at high concentrations. High boron concentrations in soil reduce crop productivity in many areas of the world. The effect of increasing levels of boron (0, 0.50, 1.00, 1.50, 2.00 mm ) on oxidative stress, antioxidant defence response and changes in artemisinin content in Artemisia annua were investigated in the present study. Boron toxicity reduced the growth parameters viz. stem height, fresh weight and dry weight. Treatments induced oxidative stress resulting in lower net photosynthetic rate, stomatal conductance, internal CO₂ and total chlorophyll content. The increased activities of antioxidant enzymes like CAT, POX and SOD were also noted in response to increasing levels of boron stress. However, H₂O₂ and artemisinin content were found to be high up to 1.00 mm concentration of boron compared to control, and on applying higher doses, further reduced contents were obtained. Thus, the results suggest that a mild stress of boron can be utilized for enhanced artemisinin production.     

Infection of bovine immunodeficiency virus and bovine leukemia virus in water buffalo and cattle populations in Pakistan

A survey of antibodies to bovine immunodeficiency virus (BIV) known as bovine lentivirus and bovine leukemia virus (BLV) was conducted with samples from water buffalo and cattle populations in Pakistan. A total of 370 water buffaloes and 76 cattle were tested, and 10.3% and 15.8%, respectively, were found positive for anti-BIV p26 antibodies determined by Western blotting, while 0.8% of water buffaloes and no cattle were positive for anti-BLV antibodies determined by immunodiffusion test. BIV-seropositive water buffaloes and cattle were found to have BIV proviral DNA in the peripheral blood mononuclear cells determined by nested polymerase chain reaction. This is the first report of BIV infections in water buffaloes.     

Irritant potential of triterpenoids from Ficus carica leaves

The irritant potential of total methanolic extract and five triterpenoids newly isolated from the leaves of Ficus carica investigated by open mouse ear assay. Total methanolic extract, calotropenyl acetate, methyl maslinate and lupeol acetate showed potent and persistent irritant effects.     

Effects of steam-treated rice straw feeding on growth,digestibility, and plasma volatile fatty acids of goats under different housing systems

In order to use rice straw as forage in livestock feeding, the effects of steam-treated rice straw (at 15.5 kgf/cm² for 120 s) feeding on growth performance, plasma volatile fatty acid profile, and nutrient digestibility of goats were determined. Twenty male goats (18.69?±?0.34 kg) were used in an 84-day trial. The goats were divided into four groups of five goats each to receive steam-treated (STRS) or untreated (UTRS) rice straw diet under closed house (CH) and open house (OH) systems. The results revealed that the goats fed with STRS had significantly higher dry matter (DM), organic matter (OM), crude protein (CP), neutral detergent fiber (NDF), and acid detergent fiber (ADF) digestibility; similarly, the average daily weight gain and feed conversion ratio were higher for STRS groups under both CH and OH systems than those for UTRS. The plasma protein and insulin in STRS and cholesterol in UTRS groups was higher (P?P?>?0.05) at 30 days. The plasma amylase, lipase, T₃, T₄ and glucagon at 30 and 60 days were not different (P?>?0.05) among the groups. The plasma acetate, propionate, butyrate, and total volatile fatty acid were higher (P?P?>?0.05) on these parameters. It could be concluded that steam treatment of rice straw at 15.5 kgf/cm² for 120 s increased apparent nutrient digestibility, hence increased the growth and feed efficiency of growing goats.     

Evaluation of pregnant rabbits as a laboratory model for bovid herpesvirus-4 infection

A field strain (87-8363) of bovid herpesvirus-4 (BHV-4) isolated from an aborted bovine fetus was used to inoculate pregnant rabbits. Eleven rabbits in midgestation were alloted to 4 groups consisting of 3 infected groups and 1 control group. Rabbits were inoculated with BHV-4 or mock-infected cell culture preparations via IV, intravaginal, and intrauterine routes. Mild vulvovaginitis and endometritis were observed after intravaginal and IV inoculation of BHV-4, whereas intrauterine inoculation of BHV-4 resulted in abortion of hemorrhagic fetuses and nonsuppurative endometritis. Virus was successfully isolated from organ explants of fetal tissues. Rabbits seroconverted 1 week after infection as detected by results of an indirect immunofluorescence assay.