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71.
Pankaj Kumar Mishra Shekhar Chandra Bisht Krishnan Jeevanandan Sanjay Kumar Jaideep Kumar Bisht Jagdish Chandra Bhatt 《Archives of Agronomy and Soil Science》2013,59(6):799-815
Plant growth-promoting bacteria (PGPB) Pseudomonas lurida-NPRp15 and Pseudomonas putida-PGRs4 possessing multiple plant growth-promoting traits were isolated from rhizoplane of pea and rhizosphere of garlic, respectively. The effects of individuals and combinations of Pseudomonas spp. with effective root nodulating symbiotic nitrogen fixing Rhizobium leguminosarum-FB1 on plant growth, nutrient uptake and yield of the rajmash plant were studied under greenhouse conditions. Bacterial inoculation resulted in significantly higher values for plant dry biomass, N, P, K, Zn and Fe contents as compared to the uninoculated control. Furthermore, dual inoculation of P. lurida-NPRp15 with R. leguminosarum-FB1 significantly increased root and shoot dry weight, nodulation, nutrient uptake, pod yield, and nutrient content of pods of rajmash VL63 compared to controls, single and triple inoculation. The results of the study indicate the potential of harnessing the benefit of plant growth-promoting and nitrogen-fixing microorganisms to improve the growth and yield of rajmash. 相似文献
72.
Kazem Poustini Fazli Mabood Donald L. Smith 《Acta Agriculturae Scandinavica, Section B - Plant Soil Science》2013,63(4):293-298
Abstract Methyl jasmonate (MeJA) has recently been shown to act as a plant-to-bacteria signal. We tested the hypothesis that pre-induction of Rhizobium leguminosarum bv. phaseoli cells with genistein and/or MeJA would at least partially overcome the negative effects of low root zone temperature (RZT) on bean nodulation, nitrogen fixation and plant growth. Otebo bean plants were grown at constant air temperature (25oC) and two RZT regimes (25 and 17oC) and inoculated with R. leguminosarum bv. phaseoli pre-induced with MeJA and/or genistein. Our results indicate that low RZT inhibited nodulation, nitrogen fixation and plant growth. The plants growing at low RZT began fixing nitrogen seven days later compared to those at higher RZT. The low RZT plants had fewer nodules, lower nodule weight, less N fixation, slower plant growth, fewer leaves, smaller leaf area, and less dry matter accumulation comared to plants at a higher RZT. Rhzobium leguminosarum bv. phaseoli cells induced with genistein and/or MeJA enhanced bean nodulation, nitrogen fixation and growth at both optimum and suboptimum RZTs. The results of this study indicate that MeJA improves bean nitrogen fixation and growth at both optimum and suboptimum RZTs, and can be used alone or in combination with genistein to partially overcome the low RZT induced inhibitory effects on nodulation and nitrogen fixation. 相似文献
73.
Four simulation models were tested for their suitability as a basic growth model in a decision support system for sugar beet growing in The Netherlands. SUCROS and SUBEMO are complex, mechanistic models; LINTUL and PIEteR are relatively simple regression models including causal relationships at a higher level of integration. All four models are dynamic, i.e. they calculate daily development and production rates.
The selected model had to be able to predict root and sugar yields accurately and to correct for suboptimal water contents of the soil. It should be possible to include location-specific data and new modules, e.g. for nitrogen fertilization or plant density. Finally, the farmer should be able to collect the required input data easily and cheaply.
The tests showed that PIEteR predicted root and sugar yields best, partly because it contained water-balance corrections, based on location-specific soil characteristics. PIEteR could not be applied universally because of its regression character at a high level of integration, but it met the requirements specified. 相似文献
The selected model had to be able to predict root and sugar yields accurately and to correct for suboptimal water contents of the soil. It should be possible to include location-specific data and new modules, e.g. for nitrogen fertilization or plant density. Finally, the farmer should be able to collect the required input data easily and cheaply.
The tests showed that PIEteR predicted root and sugar yields best, partly because it contained water-balance corrections, based on location-specific soil characteristics. PIEteR could not be applied universally because of its regression character at a high level of integration, but it met the requirements specified. 相似文献
74.
75.
‘薄壳1号’是仁用杏‘优一’的实生栽培变种,丰产性强,盛果期平均株产杏核11.1 kg,出仁率42.35%~45%。核壳厚度0.9~1.12 mm,具有结果量越大,核壳越薄的特性。 相似文献
76.
77.
John W.PATRICK 《浙江大学学报(农业与生命科学版)》1990,(4)
The instablity of the stimulation of photosynthate unloading from seed coats of Phaseolus vulgaris by abscisic acid (ABA ) and benzylamino purine ( BAP ) was studied in terms of experimental conditions. ABA stimulated photosynthate unloading at pH 6 and pH 8 without close dependence upon pH. ABA at a concentration range of 10-5-10-4 mol/L displayed stimulatory effect. However, BAP revealed no effect at a concentration range of 10-6-10-4 mol/L. Experiments designed with different transport time of 14C-photosynthate indicated that ABA might act at the plasma membrane of the unloading cells. Reducing endogenous ABA level by diminishing leaf area did not facilitate the manifestation of exogenous ABA function. Potassium ion stimulated photosynthate unloading from seed coats with highest promotion at 100 mmol/L K . However, no dependence of ABA stimulation of photosynthate unloading on K was found. 相似文献
78.
Breeding planning and variety valuation can be supported only if weighting factors for the economically relevant performance traits are available. In plant breeding they are necessary for the calculation of selection indices as well as for the comparison of varieties and for quantifying the monetary impact of breeding progress. In this article the economic weights for the most important performance traits of sugar beet are calculated from the farmer's, the sugar factory's, and the national economy's point of view. Based upon economic weights for beet yield, sugar content, potassium, sodium, and ammo nitrogen content, a total of 19 varieties was compared with regard to physical and economic performance. The investigation shows that “best” and “worst” varieties differ in gross margin per ha by 270.— to 330.— DM. Indications were given for possibilities and limitations of the application of economic weights in breeding planning. 相似文献
79.
Productivity of maize ( Zea mays L.) legume intercrops is determined by soil, management, and environment. Planting sequence and time and N fertilization are easily controlled management factors but their effects on intercrop yields are not well understood. Maize grown in monoculture or intercropped with polebean ( Phaseolus vulgaris L.) or cowpea ( Vigna unguiculata [L.] Warp.) was studied for two growing seasons at Morgantown, WV. Crops were seeded in the following sequences: maize before legume, both at the same time, and legume before maize. Planting times were early May or mid June. Nitrogen was applied at 0 or 160 kg ha−1 . Maize grain and forage, legume grain and forage, and total forage production were determined on a dry matter basis. Intercropping (average of all treatments) reduced maize grain and forage yields compared to maize in monoculture but had no effect on total forage production. However, total forage production was greatest when the seeding sequence was maize intercropped at the same time or before cowpea. Cowpea never produced grain, but forage production was almost double that of polebean. Maize produced most forage when seeded before the legumes, and the legumes produced most forage when seeded before maize. Early planting increased maize production and decreased legume production. Nitrogen increased maize grain, maize forage, and total forage yields but had not effect on legume forage production. It is concluded that maize/legume intercrops show promise for increasing forage production in temperate areas and more research on planting times and densities, weed control, harvesting and management is needed. 相似文献
80.
BACKGROUND:Grey mould (Botrytis cinerea Pers. ex Fr.) is a damaging disease affecting container-grown Calluna vulgaris (L.) Hull. Trials were conducted to test anilinopyrimidine fungicides (pyrimethanil, cyprodinil and mepanipyrim), azoxystrobin and tolylfluanid for crop safety on cultivars, and to evaluate spray programmes based on alternating these fungicides with different modes of action for disease control. Timing and application at different spray intervals were also investigated. RESULTS:Cyprodinil was slightly phytotoxic on only one of the seven cvs tested. Alternating nine-spray programmes of azoxystrobin with an anilinopyrimidine or tolylfluanid, or an anilinopyrimidine with tolylfluanid, with the first spray applied immediately after potting, were equally effective in reducing disease incidence and severity compared with untreated plants. Spray programmes of five or eight sprays, using an anilinopyrimidine and at least one other fungicide with a different mode of action, applied alternately or in blocks of two sprays of the same fungicide and immediately after potting, were equally effective in reducing disease. Omission of early fungicide sprays until 9 weeks after potting and subsequent alternate application of pyrimethanil and tolylfluanid with a different mode of action at 6 week intervals gave reduced disease control. CONCLUSION:There is potential to use spray programmes based on alternating anilinopyrimidines with fungicides with a different mode of action to provide effective control of B. cinerea on C. vulgaris. 相似文献