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Effects of salt stress on germination, seedling growth and activity of antioxidant enzymes in leaves of six cultivars of canola (Brassica napus L.) were investigated on two F1 hybrids (Hyola401, Hyola330) and four open pollinated cultivars (Zarfam, Okapi, RGs003 and Sarigol). Seeds were germinated under various levels of salinity (0, 50, 100, 150 and 200 mM NaCl solutions). An increase in NaCl concentrations progressively inhibited seed germination. Hyola401 showed the highest germination percentage at all salinity levels. Seedling growth parameters were affected by salt stress particularly at 150 and 200 mM. Leaf antioxidant activities of superoxide dismutase (SOD), ascorbate peroxidase (APX) and glutathione reductase (GR) were increased by salinity increase up to 150 mM while decreased at 200 mM NaCl concentration. Although constitutive levels of activity of antioxidative enzymes were almost the same among the canola cultivars, Hyola401 induced antioxidant enzyme activities were more efficient when subjected to NaCl treatment. Among the tested cultivars, F1 hybrid ‘Hyola401’ could be considered as salt tolerant as possessing higher germination percentage, better seedling growth and antioxidant activities under salinity stress. On the other hand, F1 hybrid ‘Hyola330’ performed inferior to said aspects and was the most susceptible cultivar to salinity stress. Key words: Canola; Brassica napus; Salinity; Antioxidant enzyme; NaCl; Germination DOI: http://dx.doi.org/10.3329/bjb.v40i1.8000 Bangladesh J. Bot. 40(1): 67-73, 2011 (June)

Full-fat canola seed (FFCS) is a locally produced alternative protein source that has potential for inclusion in the diet of ostriches. Chicks aged 84 days and weighing 24.7 ± 0.36 kg were fed five iso-nutritional diets with varying levels of FFCS. Birds were fed until slaughter at 309 days old (93.2 ± 1.82 kg). In each feeding phase, FFCS replaced soybean oilcake meal incrementally (0%, 25%, 50%, 75% and 100% of protein source). Dry matter intake (DMI) during the grower phase was lowest (1.52 kg/bird/day) for the 100%FFCS diet. Birds on the 100%FFCS also showed a 34% slower growth rate (average daily gain of 152.0 g/bird/day) compared to the other four diets (average growth rate of 230 g/bird/day) during the grower phase. The 0%FFCS (236.2 g/bird/day) and 50%FFCS (267.8 g/bird/day) diets resulted in a higher ADG. End weights during the grower phase for 0%FFCS, 25%FFCS, 50%FFCS and 75%FFCS (74.8, 72.2, 76.8, and 72.5 kg, respectively) did not differ significantly. The 100%FFCS resulted in a lower end weight (67.4 kg) for the growth phase, when compared to the 0%FFCS and 50%FFCS diets. For the overall trial period, the only differences were in ADG, with the 0%, 50% and 75%FFCS replacement diets showing the fastest growth. Fat pad weight was the only slaughter trait that revealed differences between diets, with 50%FFCS resulting in the heaviest fat pad weight. A maximum of 20.6% inclusion of FFCS should be used in diets in the grower phase, although in the other phases, FFCS could be included up to the maximum level evaluated (100% replacement of soybean oilcake meal) without detrimental effects on production parameters.Keywords: Average daily gain, Brassica napus, dressing percentage, dry matter intake, feed conversion ratio, glucosinolates, Struthio camelus

Aim. The study of possible unintended biochemical peculiarities of newly obtained herbicide-resistant canola (Brassica napus L.) plants expressing the lox-dependent BAR gene was the aim. Methods. Total soluble protein content, total free radical scavenging activity, and superoxide dismutase activity have been investigated using Bradford’s, DPPH, and nitroblue tetrazolium assays, respectively. Fresh weight of plants grown on media with or without phosphinothricin was also measured. Results. The antioxidant activity of leaf extracts of untransformed plants under in vitro growth condi-tions had no significant differences in comparison with ones of phospinothricin-resistant plants in the third generation. No significant changes in parameters investigated were observed in transgenic plants cultivated on media with herbicide addition compared to ones grown on media without it. Fresh weight and total soluble protein content were similar in transgenic and untransformed canola plants under growth without phosphinothricin. Conclusions. Lox-dependent BAR gene introduction and expression resulted in no significant differences in leaf antioxidant activity in transgenic canola plants comparing to untransformed controls.Keywords: Brassica napus, antioxidant activity, DPPH, glufosinate, superoxide dismutase.

The characteristics of thirst elicited by injections of hypertonic NaC1-solution into the 3rd brain ventricle were studied in goats supplied with permanent ventricular canola. Animals in normal water balance drank 1.5 to 2.0 1 of water within 2 min after the intraventricular injection of 0.1 ml of 0.85 M NaC1. In the hydrated animal this thirst response was markedly diminished or completely absent. If the goats were not allowed to quench their thirst immediately after the intraventricular injection of hypertonic NaC1, the urge to drink gradually became weaker and disappeared after about 20 min. Single or repetitive injections of 0.1 ml of 0.85 M NaCl into the 3rd brain ventricle were further found to cause a conspicuous increasz in urinary excretion of Na+ and C1– and to inhibit temporarily an established water diuresis. Aldosterone treatment did not prevent the increase in urinary electrolyte excretion occurrinz after injections of hypertonic NaCl into the 3rd ventricle. Repetitive injections of 0.1 ml of 0.85 M NH4Cl or of 1.7 M d-glucose into the 3rd ventricle, or injections of 0.1 ml of 0.85 M NaCl into the lateral ventricle did not induce drinking or cause any increase in urinary electrolyte excretion.

Areskog, N.-H., G. Arturson and G. Grotte. Studies on heart lymph. I. Kinetics of 131I-albumin in dog heart-lung Preparations. Acta physiol. scand. 1964. 62.209–217. — The transport of 131I-albumin from plasma to lymph was studied in dog heart-lung preparations. Cannulation of a lymph vessel mainly draining the left ventricle was performed. After injection of the labelled substance, plasma mixing was complete within a few minutes. The plasma concentration of the tracer was constant for 2–3 hours. During this time plasma and heart-lymph samples were collected. The increase in the concentration of the labelled substance in heart-lymph showed a time course indicating that the substance from the intra-vascular compartment was mainly distributed to a single extra-vascular compartment. The data could thus be fully explained by a two-compartment model and the permeability constants and the size of the extra-vascular albumin space drained by the lymphatic canola could be calculated. The present experimental approach therefore allowed a “quantitative lymph experiment”, i. e. the size of the extra-vascular albumin space drained by a lymphatic cannula could be defined and also an idea of the amount of albumin filtered across the capillary walls and the rate of removal of albumin from the extra-vascular space via the lymphatics was obtained.