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71.
R. W. Gibson 《Potato Research》1979,22(3):223-236
Summary Near Cochabamba in Bolivia, plants ofSolanum berthaultii with sticky-tipped foliar hairs only have been collected but further south near Sucre, both sticky-tipped and pointed-tipped
forms of this species and ofS. tarijense occur. Further south still, in Tarija, and in the border region of Argentina, only pointed-tippedS. tarijense has been collected but at Salta sticky-tippedS. tarijense has been found.
InS. tarijense andS. herthaultii, the presence of sticky-tipped hairs (for which an aqueous fluoroscein solution is a selective stain) on adult foliage is
controlled by a single dominant gene: plants with this character were more resistant to the aphidMyzus persicae and to the miteTetranychus urticae, and trapped more of the thripsThrips tabaci. In addition to the dominant gene, at least one set of recessive genes was needed for the full expression of this character
in crosses withS. phureja and withS. tuberosum ev. Pentland Crown.T. urticae were trapped on second-generationS. tuberosum × berthaultii with this type of hair.
Part of this work was done at the International Potato Center (CIP), Apartado 5969, Lima, Peru. 相似文献
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Three horses were presented for treatment of chronic infections of the digital flexor tendon sheath. Clinical signs included severe lameness, and heat, pain and swelling of the digital flexor tendon sheath. The horses were treated with surgical lavage of the tendon sheath, systemic and local antibiotics, and analgesics. In each case, resolution of the lameness occurred over weeks to months. Only one horse returned to athletic activity, while the other two became comfortable at pasture. Response to treatment in cases of chronic tenosynovitis may not be as rapid or complete as that reported for acute tendon sheath infections. 相似文献
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Total carbon and nitrogen abundances were determined by using combustion-gas chromatographic techlniques. Weighited mean analyses for butlk fines were 225 and 140 ppm total carbon and 150 anid 100 ppm total nitrogen. Total carbon in fine breccia was 230 ppm; in coarse breccia, 100 ppmn; in fine-grained rock, 70 ppm; and in mediumn-grained rock, 64 ppm. The finest sieved fraction had the highest carbon content. Total nitrogen in fine breccia was 125 ppm; in coarse breccia, 100 ppm; in fine-grained rock, 115 ppm; and in medium-grained rock, 30 ppm. The total carbon and nitrogen finies appeat to be mixtuires of indigenous lunar material togetheer with meteoritic and solar wind components. 相似文献
78.
Field potato plants sprayed with a mixture of a pyrethroid (cypermethrin at 40 g a.i./ha) and a paraffinic oil (Sunoco Sunspray 7E at 7 /ha) were colonized by fewer aphids and were less frequently diseased by potato virus Y (PVY) than unsprayed plants or plants sprayed with either cypermethrin or the oil alone; aphids given access to leaves of PVY-infected field plants sprayed with the mixture were also less likely to transmit PVY to laboratory test plants than aphids given access to leaves of plants sprayed with either chemical alone, or to untreated leaves. When alate aphids were confined above virus-infected and healthy plants, combined oil and cypermethrin treatment also gave greater protection against virus inoculation than either chemical alone. Electrostatic charging of spray droplets increased chemical deposits on field plants, especially when the plants were small and on upper leaves. These greater deposits improved control of PVY by the oil and the cypermethrin, individually or in combination, and enhanced the aphicidal action of the cypermethrin. 相似文献
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