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21.
Lentil (Lens culinaris ssp. culinaris), is a self-pollinating diploid (2n?=?2x?=?14), cool-season legume crop and is consumed worldwide as a rich source of protein (~24.0%), largely in vegetarian diets. Here we report development of a genetic linkage map of Lens using 114 F2 plants derived from the intersubspecific cross between L 830 and ILWL 77. RAPD (random amplified polymorphic DNA) primers revealed more polymorphism than ISSR (intersimple sequence repeat) and SSR (simple sequence repeat) markers. The highest proportion (30.72%) of segregation distortion was observed in RAPD markers. Of the 235 markers (34 SSR, 9 ISSR and 192 RAPD) used in the mapping study, 199 (28 SSRs, 9 ISSRs and 162 RAPDs) were mapped into 11 linkage groups (LGs), varying between 17.3 and 433.8 cM and covering 3843.4 cM, with an average marker spacing of 19.3 cM. Linkage analysis revealed nine major groups with 15 or more markers each and two small LGs with two markers each, and 36 unlinked markers. The study reported assigning of 11 new SSRs on the linkage map. Of the 66 markers with aberrant segregation, 14 were unlinked and the remaining 52 were mapped. ISSR and RAPD markers were found to be useful in map construction and saturation. The current map represents maximum coverage of lentil genome and could be used for identification of QTL regions linked to agronomic traits, and for marker-assisted selection in lentil.  相似文献   
22.
The essential oil of fruits of Zanthoxylum alatum (Rutaceae)proved repellent to the insect Allacophora foveicollis and fungistaticto 24 fungi, including aflatoxin-produting strains of Aspergillusflavus and A. parasiticus at a minimum dose of 2.0 x 103 µll–1.The fungistatic property of the oil was not affected by hightemperature, prolonged storage and increased inoculum. Essential oil, Zanthoxylum, antifungal, insect repellent  相似文献   
23.
Twenty-two genotypes of five Brassica species (oilseed rapeand mustard), consisting of two different maturity groups anddiffering in plant morphology, were grown on sandy soil withoutpost-sowing irrigation during 1982–83 winter season. Canopytemperature (Tc minus air temperature (Ta, stomatal conductance($) and osmotic adjustment were studied on two different deardays corresponding to the siliqua formation stage in early duration(137–150 d) and late maturing genotypes (151–165d) of oilseed Brassicas. The absolute mid-day values of transpirationalcooling (Tc–Ta) were relatively higher in B.juncea andB. carinata than in B. tomifortii, B. napus and B. campestris.Tc-Tm showed a genetic variability ranging from 0-5 to 4 Cfor early maturing genotypes, and from 0–5 to 5 C forlate maturing genotypes. Mid-day Tc–Ta showed significantpositive correlation with Kh osmotic adjustment and seed yieldin Brassica cultivars. Early genotypes out-yielded the latematuring ones, despite the lower values of AT, and Tc–Taat siliqua formation in the former rather than later group ofcultivars. It is suggested that average mid-day Tc–Taas observed with an infrared thermometer, could effectivelybe used as a technique to screen Brassica genotypes for droughttolerance under receding soil moisture conditions.  相似文献   
24.
FACTORS CONTROLLING STOLON DEVELOPMENT IN THE POTATO PLANT   总被引:5,自引:3,他引:2  
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The spatial distribution and density of scientists can have important implications for key aspects of scientific processes, such as innovation, networking, rates of knowledge exchange and success in large competitive grants. In this paper, we examine the research output of different research organizations and universities in Australia, with the aim of identifying hotspots of ecological research and how these hotspots have changed over the last 20 years. We used publications from 10 reputable peer‐reviewed international journals as a measure of research output. We identified a number of ecology hotspot clusters. Some clusters have developed significantly over the last 20 years, while others have declined in output over time. The University of Sydney, University of Queensland, James Cook University and Melbourne University had the largest output levels among universities. Results also showed large increases in output over the last 5‐year period (2006–2010), possibly because of the impending introduction of the Excellence in Research for Australia.  相似文献   
29.
The plastid genome regions of two intergenic spacers, psbA–trnH and trnL–trnF, were sequenced to study the nucleotide diversity and phylogenetic relationships among Gladiolus cultivars. Nucleotide diversity of psbA–trnH region was higher than trnL–trnF region of chloroplast. We employed Bayesian, maximum parsimony (MP) and neighbour-joining (NJ) approaches for phylogenetic analysis of Gladiolus and related taxa using combined datasets from chloroplast genome. The psbA–trnH and trnL–trnF intergenic spacers of Gladiolus and related taxa-like Babiana, Chasmanthe, Crocus, Iris, Moraea, Sisyrinchium, Sparaxis and two out group species (Hymenocallis littoralis and Asphodeline lutea) were used in the present investigation. Results showed that subfamily Iridoideae have sister lineage with subfamily Ixioideae and Crocoideae. H. littoralis and A. lutea were separately attached at the base of tree as the diverging Iridaceae relative’s lineage. Present study revealed that psbA–trnH region are useful in addressing questions of phylogenetic relationships among the Gladiolus cultivars, as these intergenic spacers are more variable and have more phylogenetically informative sites than the trnL–trnF spacer, and therefore, are suitable for phylogenetic comparison on a lower taxonomic level. Gladiolus cultivars are extensively used as an ornamental crop and showed high potential in floriculture trade. Gladiolus cultivation still needs to generate new cultivars with stable phenotypes. Moreover, one of the most popular methods for generating new cultivars is hybridization. Hence, information on phylogenetic relationships among cultivars could be useful for hybridization programmes for further improvement of the crop.  相似文献   
30.
Rhizoctonia solani anastomosis group (AG) 11 causes serious damping‐off and hypocotyl rot of narrow‐leafed lupins (Lupinus angustifolius) in the northern grain‐belt of Western Australia. R. solani AG‐11 produced abundant sclerotia in sand overlaid on potato dextrose agar. Sclerotia were produced in larger numbers in natural Lancelin sand than in Geraldton loamy sand collected from the northern grain‐belt of Western Australia. The majority of the sclerotia produced were in >250 to <500 μam size range. The germination levels of sclerotia in the first two cycles of drying and germination were not significantly different. Sclerotia still retained 50% germination after four such cycles, indicating that they may have the ability to withstand the climatic cycles of the Mediterranean environment of southwestern Western Australia. The radial growth of the mycelium from sclerotia, however, declined with each drying and germination cycle. Inoculum potential of the pathogen increased with the size of sclerotia resulting in more severe lupin hypocotyl rot with larger sclerotia. The number of sclerotia produced in soil increased with increasing density of lupin seedlings. The results also indicate that R. solani AG‐11 can produce sclerotia on infected plant tissues as well as in soil. This is the first report of the prolific production of sclerotia by AG‐11 and their significant role in infection of lupins in soil in Western Australia.  相似文献   
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