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21.
Abstract

Canola (Brassica napus L.), is the most important oilseed crop due to high oil contents and low concentration of erucic acid and glucosinolates. In Pakistan, oil seed production is not sufficient to fulfill the needs of the country. Thus, the planned experiment was aimed to evaluate the performance of different canola cultivars i.e. Faisal Canola, Pakola, PARC Canola hybrid and Rainbow at grown under various soil applied boron (B) levels viz., 0, 1, 2?kg ha?1 under a rainfed environment. The experiment was laid out in randomized complete block design with four replications. Among the canola cultivars, the maximum seed oil contents were recorded in cultivar ‘Pakola’ whereas, higher linolenic acid and protein were recorded in cultivar ‘Faisal canola’ as compared to other cultivars. A synergistic effect was found between various levels of B and quality parameters of the canola seed; as higher concentration of oil contents were found when B was applied 2?kg ha?1. Conversely the linolenic acid showed the antagonistic behavior with the various B levels. On the other hand, protein contents, oleic acid and erucic acid revealed non-significant differences under different B application rates. In conclusion, the cultivar ‘Pakola’ provided the highest oil content when the B was applied at 2?kg ha?1; the low concentration of unsaturated fatty acid was observed in ‘PARC canola’ cultivar in the Pothwar region of Punjab, Pakistan.  相似文献   
22.
We investigated the role of gibberellins-producing endophyte Penicillium janthinellum LK5 associated with Solanum lycopersicum (host), abscisic acid (ABA)-deficient tomato mutant Sitiens and its wild-type Rheinlands Ruhm (Rhe) plants under cadmium (Cd) stress. A 100-μM Cd application to host, Sitiens and Rhe reduced the shoot growth, chlorophyll content and stomatal conductance. However, these parameters were significantly (P?<?0.0011) higher (1.0- to 2.6-folds) in host, Sitiens and Rhe under endophytic association than in non-endophyte infected plants (control) under Cd stress. Furthermore, endophytic association minimized the Cd-induced membrane injury and oxidative stress to host, Sitiens and Rhe plants by reducing electrolytes and lipid peroxidation while increasing the content of reduced glutathione and catalase activities as compared to non-endophyte-infected plants. Stress-responsive ABA content significantly increased (~2-folds) in Sitiens and Rhe under endophyte association, while in host plants it was decreased under Cd stress. Salicylic acid content was ~?1.7-fold higher in host, Sitiens and Rhe plants under Cd stress and endophyte association than in the control. Besides gibberellins production, the endophyte has the potential to solubilize phosphates (12.73?±?0.24 mg/l) since higher P was observed in the roots of Sitiens, Rhe and host plants. Similarly, nutrients like sulfur and calcium were more efficiently assimilated in roots of endophyte-associated plants than control under Cd stress. Conversely, Cd accumulation was significantly decreased (P?<?0.001) in the roots of endophyte-inoculated host, Sitiens and Rhe than control. In conclusion, endophyte symbiosis can counteract heavy metal stress which can exert negative effects on plant growth.  相似文献   
23.

For effective varietal improvement of horticultural crops peach (Prunus persica) and nectarine (Prunus persica var. nucipersica), information about their population structure and genetic relatedness plays an important role. In this study we used retrotransposon-based markers (iPBS) to estimate the genetic diversity and population structure of 48 peach and nectarine genotypes from various distinct geographical regions of Punjab and Khyber Pakhtunkhwa, Pakistan. A total of 461 alleles were identified from PCR amplicons derived from nine iPBS primer pairs with an average of 8.5 alleles/locus. Among all four groups the genotypes collected from Swat and Hunza had the highest and the lowest expected heterozygosity, unbiased expected heterozygosity and Shannon’s information index, respectively. We constructed a Neighbour-Joining dendrogram and performed principal coordinate analysis based on the distance matrices, and both forms of analysis grouped the 48 genotypes into two distinct clusters. The STRUCTURE software distributed the forty-eight genotypes into two main populations (k?=?2) indicating a low diversity between genotypes collected from Chakwal, Swat, Mansehra and Hunza.

  相似文献   
24.
The present study was designed to evaluate different honey samples obtained from local market for their quality parameters for assessment of their feasibility for foreign export by comparing it with international standards. The study was conducted at PCSIR laboratories complex, Peshawar, during 2006. The tested samples were evaluated for moisture content, Ash percentage, acid content, HMF and reducing sugars percentage. The moisture content of locally produced honey was in the range of 14.5 to 18.23%. The ash content of locally produced honey samples ranged between 0.047-0.35 which is within the standard limits. The acid content of the honey samples ranged between 19.5 and 38.0 meq kg(-1). The HMF contents of locally produced honeys ranged from 5.3 to 23.20 mg kg(-1). The content of reducing sugar of the tested samples ranged between 43.14 and 81.40% for the tested samples of locally produced honey. All of the samples were found to be in acceptable range of international standards for all of the tested parameters except for only one sample with lower reducing sugars. These samples were marked to be according to the international standards and are healthy for human consumption.  相似文献   
25.
The impact of extrusion on physical and sensory properties and on the in vitro bile acid (BA) binding was examined for N979 and Jim oat (Avena sativa) lines with 8.1 and 4.8% β‐glucan, respectively. Based on hardness and edibility of products made from Jim oats, moisture concentrations of 16–25% and temperatures of 165–180°C were selected for N979 extrusion. Jim‐based cereal had a significantly greater (P < 0.05) expansion ratio than did N979‐based cereal at most moistures. N979 cereal was browner, but not harder, than Jim cereal. Extruded products from N979 and Jim oats had 5.29–5.99% and 3.38–3.94% β‐glucan, respectively. Changing extrusion temperature or moisture content did not affect β‐glucan concentration in the products. N979 cereal made at 165°C and 16% moisture had greater BA binding than at other conditions, and had crunchiness comparable to cereals made at other conditions. BA binding of Cheerios brand breakfast cereal was close to that of N979 cereal made at 180°C and 18% moisture, but lower than cereals made at other conditions. Cereals made from Jim and N979 oats were browner, harder, coarser, and crunchier than Cheerios breakfast cereal. Proper processing and preparation techniques should be considered when producing extruded products from high β‐glucan oats.  相似文献   
26.
27.
Theileria parva causes widespread morbidity and mortality in cattle in endemic regions. An outbreak of theileriosis occurred on a farm near Ladysmith in KwaZulu-Natal, South Africa, which is not a declared Corridor disease-infected area. A survey of Red Brangus cattle from all age groups and areas of the farm was performed. Transmission of the parasite from infected animals on the farm to susceptible animals by tick transmission and tick-stabilate injection, was attempted. The survey indicated high numbers of animals with antibody titres to T. parva but only 6 infected animals, based on real-time PCR and RLB analysis. The transmission experiments failed to transmit the parasite. The study shows the difficulty in elucidating a source of infection and determining the dynamics of new infections in a herd where multiple possible sources are present and treatment with tetracyclines has taken place.  相似文献   
28.
Eighteen isolates of Rhizoctonia solani collected from infected rice plants in four different locations of Bangladesh were studied by using morphological characters and molecular markers. Anastomosis study with a reference isolate confirmed that all the isolates belonged to R. solani. Significant variation was observed in sclerotial size, shape and distribution. Un-weighted pair group method with arithmetic mean dendrogram constructed based on the Gower's general similarity coefficient showed that these isolates were grouped into four clusters at the 0.68 similarity coefficent according to morphological characters. Cluster I was a major cluster consisting of 13 isolates, while clusters Ⅱ to Ⅳ consisted of 1 or 2 isolates. Analyses by variable number of tandem repeat and amplified fragment length polymorphism markers showed that the isolates were grouped into five and three clusters at a similarity coefficient of 0.64 and 0.69, respectively. Although most of the variability was found between isolates from different regions as expected, significant variation was observed within the isolates collected from similar agro-ecological regions. Our results suggest the presence of different races of R. solani within the same local geographic regions.  相似文献   
29.
The effect of Prohexadione Calcium (Pro-Ca) and daminozide was observed on the growth characteristics and endogenous gibberellin contents of Chrysanthemum morifolium R. cv Monalisa White. Three concentrations viz. 100, 200 and 400 ppm of Pro-Ca and a single concentration of daminozide (800 ppm) were applied three times with 7 days interval on three weeks old plant under greenhouse condition. Pro-Ca suppressed the plant length up to 30.7% while daminozide inhibited up to 27.12% at optimum concentration. The chlorophyll contents and stem diameter were higher than control, while the fresh weight and flower number insignificantly reduced with such treatments. Gibberellin (GA) analysis showed that Pro-Ca and daminozide application significantly lowered bioactive GA1 content, although the amount of its immediate precursor GA20 was fractionally higher. Bioactive GA4 content was slightly higher than the control while significant difference in GA9 was found between the plants treated with Pro-Ca and daminozide. Current study showed that both early C13 hydroxylation and non-C13 hydroxylation pathways of GA biosynthesis are operational in C. morifolium.  相似文献   
30.
Lignans from Strophanthus gratus   总被引:4,自引:0,他引:4  
Three lignans, pinoresinol (1), 8-hydroxypinoresinol (2) and olivil (3) have been isolated from the leaves of Strophanthus gratus by reversed-phase HPLC.  相似文献   
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