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31.
32.
Summary Helicoverpa armigera is one of the important insect pests adversely affecting the yield of potatoes in India. A synthetic gene encoding the insecticidal crystal protein (Cry1Ab) ofBacillus thuringiensis (Bt) has been introduced into five genotypes of potato usingAgrobacterium tumefaciens. Southern analysis of DNA from transgenic plants confirmed the integration and copy number of the transgene. Double-antibody quantitative sandwich ELISA analysis demonstrated high levels of Cry1Ab protein expression in transgenic plants. Insect bioassays on the leaves of transgenic plants showed considerable protection against the larvae ofH. armigera in terms of leaf area consumed and larval weight reduction.  相似文献   
33.
Progeny studies of Jatropha curcas and Pongamia pinnata were carried with respect to bioproductivity,pod and seed characters which is one of the selection methods in tree improvement programmes. Variations in bioproductivity and biodiesel parameters of both the plants were compared every 6 months for 4 years of investigation and analyzed by analysis of variance and correlation coefficient by Pearson’s method using software Graphpad instat 3.06(for Windows and Mac). P. pinnata has better germination rate(71.4 %), 100 pod weight(PW)(311.59 g) and 100 seed weight(SW)(173.46 g) as compared to J. curcas for germination rate(43.2 %), 100 PW(111.29 g) and 100 SW(67.46 g). P. pinnata has strong correlation for plant height to canopy growth(CG)(0.948), collar diameter(CD)(0.994), number of branches per plant(NBP)(0.995) and to number of leaves per branch(NLB)(0.862) as compared to J.curcas which showed good correlation among plant height to CG(0.976), CD(0.970), NBP(0.988), NLB(0.920) and to number of pods per branch(0.657). However, J. curcas depicted negative correlation for pod breadth to seed length(SL)(-0.447), seed breadth(-0.248) and to seed thickness(ST)(-0.364) and among the 100 PW to SL(-0.199), ST(-0.220) and to 100 SW(-0.704). About 4 kg of P. pinnata seeds were required for each liter of crude oil which yields896 ml of biodiesel on transesterification as compared to5.66 kg of J. curcas seeds for a liter of crude oil, producing about 663 ml of biodiesel. The quality of biodiesel meets the major specification of American Society for Testing and Materials(ASTM) standards for biodiesel. The crude glycerin and seed cake obtained as byproduct during biodiesel production were also measured which can be purified and used in composting, animal feeds, pharmaceuticals and cosmetic industries.  相似文献   
34.
A total of 3611 fungal isolates were recovered from 4200 leaf segments incubated from 7 medicinal herbs during monsoon, winter and summer seasons. These fungal isolates belonged to teleomorphic Asco-mycota (23.5%), anamorphic Ascomycota producing conidiomata (17.4%), anamorphic Ascomycota without conidiomata (46.9%), Zygo-mycota (1.42%) and sterile forms (10.6%). Chaetomium globosum, As-pergillus niger, Aureobasidium pullulans, Curvularia lunata, Fusarium spp., Penicillium spp., Pestalotiopsis spp., Trichoderma viridae, Cladosporium cladosporioides, were frequently isolated from more than one host plant. The number of endophytic isolates was higher in winter than in monsoon and summer seasons.  相似文献   
35.
Attempts have been made to correlate the chemical structure of 38 pyridine derivatives, including two herbicides, picloram (Tordon) and Daxtron and a nitrification inhibitor (N-Serve), with their resistance to attack by soil microorganisms under aerobic and anaerobic conditions and with their herbicidal effect upon lucerne (Medicago sativa L., Hunter River).  相似文献   
36.
利用高效液相色谱法(HPLC)测定匙羹藤(Gymmnema sylvestre)不同器官的匙羹藤酸含量.结果表明:不同器官的匙羹藤酸含量明显小同,在顶芽、花、节点、叶、节间、根和种子的匙羹藤酸含量分别为,54.29、31.66、28.82、27.67、25.39、20.56和1.31 mg·g-1 DW.在幼叶中,匙羹藤酸(35.39 mg·-1DW)含量最高,比老叶的匙羹藤酸(23.07 mg·g DW含量高1.52倍.幼年,中年和老年节间的匙羹藤酸含量分别为26.47、25.77和23.94 mg·g-1DW,均低于叶的匙羹藤酸含量,而幼嫩,中部节和老节点的匙羹藤酸含量分别为27.96、28.81和29.66 mg·g-1 DW,均高于叶的匙羹藤酸含量.因为过度开采引起了这些植物在自然界的损耗,本研究为匙羹藤资源的发展和利用提供了科学依据.  相似文献   
37.
Data on physical properties of seeds have significant importance for machinery and process equipments design. This study was conducted to investigate some physical properties of tung seed (Aleutites Fordii) namely, dimensions, 100 unit mass, arithmetic mean diameter, geometric mean diameter, sphericity, aspect ratio, surface area, bulk density, true density, porosity, terminal velocity and coefficient of friction. The applications of these properties are also discussed. The tung seed has an average of 13.24% (d.b.) moisture and 40.37% oil content. The average seed length, width, thickness were 22.61 mm, 20.35 mm, 13.95 mm, respectively. The average surface area of tung seed is 1084.20 mm2 while the sphericity and aspect ratio were 0.82 and 90.07%, respectively. The average bulk density of seed was 0.502 g/cm3 while the true density was 0.995 g/cm3, and the corresponding porosity was 49.88%. The terminal velocity was 8.3 m/s. The static coefficient of friction on three different contacting materials has been found out and the results showed that the mean value of static coefficient friction was least in case of aluminum sheet while it is highest for plywood.  相似文献   
38.
This paper presents the influence of the gage length on the kenaf fiber Young’s modulus and the tensile strength characterization. Four different gage lengths of 10 mm, 15 mm, 20 mm and 25.4 mm are selected in this study and the tensile testing is performed at a quasi-static loading rate of 1 mm/min. The cross-sectional area of the fiber after failure is considered for the stress calculations. Weibull probability distribution is used to characterize the tensile strength of the kenaf fiber. The Weibull parameters are obtained for the two parameter, three parameter and Weibull of Weibull models and the average tensile strength of the fibers are evaluated. The predicted average tensile strength from all the three approaches are in good agreement with the experimental results for the obtained parameters.  相似文献   
39.
Summary The effect of inorganic nitrogen nutrition on the induction and development of microtubers by cytokinin-induced tuberization was studied in four potato genotypes belonging to different maturity groups. The objective of this study was to investigate whether a reduction in total nitrogen level in the Murashige & Skoog medium would improve cytokinin-induced tuberization rate. The effect of three levels of total nitrogen (15, 30 and 45 meq) on tuberization was studied at constant (20 meq K) and varying potassium levels approximating to 5, 10 and 15 meq. Reducing the total nitrogen supply increased the number but decreased the size of nitrogen level on the rate of assimilate partitioning (harvest index) during cytokinin-induced microtuberization.  相似文献   
40.
Phenotypic and genetic parameters were estimated for three body traits (harvest weight, carapace length and standard length) and for adult male morphotypes of the giant freshwater prawn Macrobrachium rosenbergii in a fully pedigreed synthetic population in India. The data set included 9,173 progeny produced over four generations from 162 sires and 234 dams. Variance components and genetic parameters were estimated fitting an animal model using the residual maximum‐likelihood methodology. The heritabilities for harvest body weight (HW), carapace length (CL) and standard length (SL) were moderate (0.22 ± 0.056, 0.22 ± 0.055 and 0.25 ± 0.059 respectively). The common environmental effects for HW, CL and SL were 0.10 ± 0.020, 0.08 ± 0.018 and 0.10 ± 0.021 respectively. As M. rosenbergii is sexually dimorphic, we estimated heritabilities within each sex. Heritability of HW in females (0.27 ± 0.068) was greater than that in males (0.15 ± 0.057). CL and SL followed the same pattern. The occurrence of male morphotypes is a unique characteristic of adult populations of M. rosenbergii. Populations from culture ponds exhibit a wide range of sizes. To examine whether there was a heritable component in male morphotype frequencies, we treated male morphotypes as traits. The additive genetic variance (and hence the heritability) was zero for male morphotype, indicating that selective breeding to increase the proportion of desirable male morphotypes would not be effective. The genetic correlations among body traits were all positive, high and approaching unity. The results are discussed in relation to selection plans for the giant freshwater prawn.  相似文献   
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