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871.
Soluble sugars and starch have been estimated during the first40 days of development of round and wrinkled pea seeds. At alltimes the wrinkled seeds contained more soluble sugars and lessstarch than the round seeds. The significance of these results,in relation to the expression of the round (RaRa) and wrinkled(rara genotypes, is discussed. Pea seeds, round, wrinkled, sugars, starch 相似文献
872.
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874.
Effects of soil incorporation on the efficacy of the rhabditid nematode, Phasmarhabditis hermaphrodita, as a biological control agent for slugs 总被引:1,自引:0,他引:1
M J. WILSON L A. HUGHES G M. HAMACHER L D. BARAHONA D M. GLEN 《The Annals of applied biology》1996,128(1):117-126
The effects of soil cultivation immediately after application of the rhabditid nematode, Phasmarhabditis hermaphrodita , to the soil surface were investigated in two field experiments. The first experiment was done in mini-plots separated by barriers, with an artificially introduced population of slugs ( Deroceras reticulatum ). Nematodes were applied as a drench at a rate of 3 times 109 ha-1 in one of two application volumes and then left undisturbed or incorporated into the soil by cultivation to 2 cm or 10 cm depth. Moist soil conditions were maintained by irrigation throughout the experiment. Nematode application significantly reduced slug damage to Chinese cabbage seedlings throughout the 7 wk duration of the experiment and the population of D. reticulatum in soil 7 wk after treatment. However, soil cultivation had no effect and did not interact with the effect of nematodes. In the second experiment, in a crop of winter wheat, nematodes were applied to soil by hand-lance at a rate of 3 times 109 ha-1 and left undisturbed on the soil surface or incorporated by spring-tine cultivation to a depth of 2, 5 or 10 cm. In this experiment, nematodes were applied to dry soil. Cultivation alone had no effect. Nematode application reduced slug damage to wheat plants in plots where nematodes were incorporated into the soil, but not where they were left on the surface. There was no detectable impact of nematodes on slug populations in the wheat experiment. 相似文献
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877.
The delphacid genus Sogatella and related groups: a revision with special reference to rice-associated species (Homoptera: Fulgoroidea) 总被引:2,自引:0,他引:2
Abstract. The delphacid planthopper genus Sogatella Fennah is redefined and a key provided to males of the fourteen included species. The type-species of Sogatodes Fennah, S.molinus Fennah is considered to be a Sogatella species and consequently Sogatodes becomes a junior subjective synonym of Sogatella. The remaining species of Sogatodes are transferred to Tagosodes gen.n . (type species T.cubanus (Crawford) comb.n. ). Latistria Huang et al. or Sogatellana Kuoh. A key is provided to distinguish the four genera. A check list of species in each genus is given. Several species are important rice pests and information on biology and pest status is summarized. 相似文献
878.