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171.
Genetic Resources and Crop Evolution - Rapeseed-mustard is one of the most important oilseed crops and providing a major source of edible oil in the world besides having other economic importance...  相似文献   
172.
Xylem sap plays a major role in long‐distance transport of water, nutrients, and metabolites. However, there is little information on the behavior of metabolites in mineral‐deficient xylem sap. For this reason, the time‐dependent changes in selected metabolites (amino acids, organic acids, and soluble sugars) from tomato xylem sap in response to nitrogen (N), phosphorus (P), or potassium (K)‐deficient condition were investigated. Tomato plants (Solanum lycopersicum L.) were grown hydroponically in liquid culture under three different mineral regimes: N‐deficient [0.5 mM Ca(NO3)2 and 0.5 mM KNO3], P‐deficient (0.05 mM KH2PO4), and K‐deficient (0.5 mM KNO3), respectively. Xylem sap was collected at 10:00 am after 1, 5, 15, and 30 d, and the selected metabolites were analyzed with liquid chromatography. All N, P, or K deficiencies led to a substantial increase in metabolites in the xylem sap. The predominant amino acid in the xylem sap was glutamine and, interestingly, all mineral deficiencies resulted in a substantial amount of γ‐aminobutyric acid (GABA). Additionally, organic acids (citrate and malate) and soluble sugars were strongly increased in all mineral deficiencies, and, in particular, the level of shikimate was greatly affected by N deficiency. Based on these data, it is necessary to clearly elucidate an unknown event taking place in xylem loading in a variety of environmental impacts, and we are now studying to expand our knowledge on metabolic and proteomic responses using GC‐MS and LC‐MS.  相似文献   
173.
Landscape Ecology - In recent years, landscape sustainability, the maintenance and improvement of biodiversity, ecosystem services, and human well-being in landscapes, has become a core objective...  相似文献   
174.
The two species under genus Echinochloa, Efrumentacea (Indian barnyard millet) and Eesculenta (Japanese barnyard millet), are cultivated for food and fodder by hilly and tribal communities in Asia particularly in India, China and Japan. The crop has wide adaptability and occupies a special place in marginal rainfed areas because of its short life cycle. Although the area under the crop has come down drastically in last 50 years, the crop ability to survive under harsh conditions makes it a better choice during famine years. In the Indian Himalayan region, the crop was traditionally used as a substitute for rice. It has been identified as a suitable choice for climate‐resilient agriculture. High nutrient content and antioxidant effects make it to be considered as a functional food crop. Recently, the demand of the crop has increased due to its highly nutritious grains. Thus, it has the potential to provide both food and nutritional security particularly in hills where nutritional deficiencies are in abundance. Despite enormous potential, the crop has not gained the popularity among masses and is still considered as poor man's food. This work therefore is an attempt to compile the meagre information available on crop history, evolution, crop breeding and present status to make the crop competitive and revamp its cultivation.  相似文献   
175.
Inheritance of white rust resistance was studied in two crosses between resistant (R) and sensitive (S) types of Brassica juncea, namely EC 12749 בParkash’ (R × S) and EC 12749 בVaruna’ (R × S) under conditions of normal and late sowing. Analysis of six generations revealed the importance of additive, dominant and epistatic effects. Disease was more prevalent under late sowing due to favourable environment. Reciprocal recurrent selection is advocated for exploiting the additive and non-additive gene effects for resistance to white rust.  相似文献   
176.
177.
We investigated the sub-lethal influences of spinosad, chlorpyriphos, endosulfan, acephate and cypermethrin on the oviposition responses of Helicoverpa armigera (Hübner) to cotton plants, under cage and laboratory conditions. The rank order of toxicity (LC50 values as a per cent) of test insecticides against third instar larvae using the leaf disc method was: spinosad > chlorpyriphos > endosulfan > acephate > cypermethrin. On whole plants, females laid more eggs on acephate LC50-, acephate LC30- and cypermethrin LC50-treated cotton plants than on the control. The chlorpyriphos-treated plants were least preferred for oviposition. When excised cotton leaves from different treatments were used in a multiple-choice test, cypermethrin LC50- and endosulfan LC30-treated leaves received more eggs than the control. The repeated application of sub-lethal concentrations of different insecticides reduced plant height in the case of acephate LC30 and cypermethrin LC50, while plant spread and upper canopy leaf area were reduced in both treatments of acephate and cypermethrin. Reduced plant spread, upper canopy leaf area followed by plant height were found associated with oviposition preference by H. armigera females.  相似文献   
178.
179.
Grid cells recorded in the medial entorhinal cortex of freely moving rats exhibit firing at regular spatial locations and temporal modulation with theta rhythm oscillations (4 to 11 hertz). We analyzed grid cell spatial coding during reduction of network theta rhythm oscillations caused by medial septum (MS) inactivation with muscimol. During MS inactivation, grid cells lost their spatial periodicity, whereas head-direction cells maintained their selectivity. Conjunctive grid-by-head-direction cells lost grid cell spatial periodicity but retained head-direction specificity. All cells showed reduced rhythmicity in autocorrelations and cross-correlations. This supports the hypothesis that spatial coding by grid cells requires theta oscillations, and dissociates the mechanisms underlying the generation of entorhinal grid cell periodicity and head-direction selectivity.  相似文献   
180.
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