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992.
Triple cropping in the inland valleys of southwestern Nigeria is technically possible but the third crop between the main crop and vegetables has poor establishment due to soil saturation. Identification of appropriate sowing methods is required in this niche. A field experiment was conducted at the University of Agriculture, Abeokuta, Nigeria in 2007/2008 and 2008/2009 cropping seasons to evaluate the effect of sowing methods on the performance of upland rice (Oryza spp.) in a lowland rice-vegetable sequence. The first, second, and third crops in the sequence were planted in May, September and December, respectively. Two upland rice varieties, namely New Rice for Africa 1 (NERICA 1) and ITA 150 constituted the main plot treatments while the subplot treatments were sowing methods. The mean grain yield of lowland rice for two years was 7.74 t ha^-1. The fluted pumpkin had a fresh leaf weight of 14.78 t ha^-1. The grain yields of the two upland rice varieties (1.81 and 1.85 t ha^-1) and sowing methods which ranged between 1.63 and 2.05 t ha^-1 were similar in both cropping seasons. However, the interaction of variety by sowing methods had a significant effect on grain yield. Transplanting and pre-germinated broadcast had the highest grain yield for NERICA 1 while dry broad cast and pre-germinated dibbled had the highest in ITA 150. Hence, the productivity of triple cropping in the inland valley was enhanced by sowing methods. 相似文献
993.
This article reports on the research development of laminated pine telephone cross-arms. Twenty-one years of service testing under extreme conditions in South-West Africa and 19 years at Magaliesburg in the Transvaal proved such cross-arms to be a success. This success has led to further development In South Africa in fields such as laminated pine railway sleepers. 相似文献
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Wister O 《Science (New York, N.Y.)》1908,28(728):837-839
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It is established on a model of experimental trichinellosis in mice that roncoleukin (rIL2) in a dose of 10000 IU/kg causes an increase in nonspecific resistance of the organism to invasion. A tendency of potentiation of the anthelmintic action of albendazole and reliable increase of the level of specific antibodies in blood serum is revealed when roncoleukin is prescribed together with specific drug. 相似文献
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R. O. Moffett 《African Zoology》2013,48(2):222-223
The complex life cycles of most trematode parasites include three hosts. The first intermediate host is a snail, the second is normally a teleost fish and a piscivorous bird serves as the definitive host. Lymnaeid snails are most likely to be responsible for cercarial shedding, which infect exposed fish and in turn are eaten by piscivorous birds. From 2008 to 2010 fish in the Okavango and Orange-Vaal River Systems were collected and dissected in order to determine the prevalence and intensity of larval trematode infections in the eyes and brains. This paper discusses the possible ecological factors which can influence the probability of certain fish species becoming infected with diplostomid cercariae and hence metacercariae. The feeding strategies and sizes of piscivorous birds, which could act as definitive hosts for the adult worms, are summarized and discussed. Information on the snail species responsible for furcocercous cercarial shedding in the two study sites is also included. 相似文献