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91.
对4个不同类型大豆品种的上、中上、中、中下、下、分枝六部分籽粒进行品质分析,各部分蛋白质和脂肪含量差异显著、极显著。蛋白质含量从上至下由高变低(40.010%、38.890%、38.110%、36.428%、35.888%);无限结荚习性大豆脂肪含量(19.983%、20.873%、21.242%、21.797%、21.908%)与蛋白质相反;亚有限结荚大豆脂肪含量上至中下由低变高(21.411%、21.993%、22.113%、22.538%),下部(22.151%)低于中下部;分枝上籽粒蛋白质、脂肪含量与中上部差异不显著;全株品质平均值(38.024%、21.760%)接近于中部值。 相似文献
92.
[目的]研究微胚乳超高油玉米籽粒胚乳消减和油分积累规律。[方法]以高油玉米115为对照,研究2种微胚乳超高油玉米籽粒的胚、胚乳、种皮及相应油分的积累规律。[结果]微胚乳超高油玉米在籽粒发育过程中胚乳干重在发育的第27 d达最大,第37 d消减基本结束;胚的重量一直增加,种子成熟时和胚乳的重量相当;整粒干重第32 d达最大。3个玉米品种授粉后的种皮干重一直增加,第32 d基本稳定,整粒油分37 d前一直增加,之后趋于稳定。微胚乳超高油玉米胚乳的油分在17~27 d增加较慢,27~37 d增加迅速,37 d到成熟期下降,比高油115的高很多;胚的油分在17~27 d增加,27 d到成熟期略下降。高油玉米115胚和胚乳的重量一直增加,胚乳的油分一直很低,胚的油分在17~27 d增加。[结论]该研究为微胚乳超高油玉米的籽粒胚乳消减机理研究提供了参考。 相似文献
93.
94.
A field study was carried out during the years 2007 and 2008 on 30-year old Zaghloul cultivar growing in clay soil. Mineral fertilization sources: N, ammonium nitrate or NPK, ammonium nitrate + calcium superphosphate + potassium sulphate, and organic sources: chicken manure (CM), cow dung (CD) and composted domestic refuse (CDR) were applied either alone or in combinations in order to study their influence on the yield and fruit physical and chemical quality characteristics. The results revealed that applying organic manure alone or in combination with mineral NPK increased palm yield as compared to mineral fertilization alone (NPK or N). In general, fruit weight, flesh weight, length, diameter and dry weight were increased, while fruit moisture content decreased by the application of organic manures either alone or in combination with mineral NPK as compared to the mineral N. Higher fruit TSS and total sugars content were obtained by the application of organic manures alone or in combination with mineral NPK as compared with mineral fertilization alone (NPK or N). Overall values of fruit minerals content did not differ among the different treatments. Organic manures fertilization (especially CM and CD) resulted in decreasing fruit lead, cadmium, nitrate and nitrite contents more than mineral fertilization. In general, the application of organic manures either alone or in combinations with mineral NPK did not differ from each other in their effect on yield and fruit quality. 相似文献
95.
96.
Methane fluxes were measured monthly over a year from tropical peatland of Sarawak, Malaysia using a closed-chamber technique. The CH4 fluxes in forest ecosystem ranged from −4.53 to 8.40 μg C m−2 h−1, in the oil palm ecosystem from −32.78 to 4.17 μg C m−2 h−1 and in the sago ecosystem from −7.44 to 102.06 μg C m−2 h−1. A regression tree approach showed that CH4 fluxes in each ecosystem were related to different underlying environmental factors. They were relative humidity for forest and water table for both sago and oil palm ecosystems. On an annual basis, both forest and sago were CH4 source with an emission of 18.34 mg C m−2 yr−1 for forest and 180 mg C m−2 yr−1 for sago. Only oil palm ecosystem was a CH4 sink with an uptake rate of −15.14 mg C m−2 yr−1. These results suggest that different dominant underlying environmental factors among the studied ecosystems affected the exchange of CH4 between tropical peatland and the atmosphere. 相似文献
97.
We developed a deterministic and stochastic age-based matrix projection population model to assess and quantify the impact of mortality caused by chronic oil pollution and legal hunting on thick-billed murre Uria lomvia populations breeding and wintering in eastern Canada. We calculate the potential population growth rate in the absence of anthropogenic mortality sources using a modeling technique that translates absolute number of birds killed from anthropogenic mortality to potential survival rates in the absence of these anthropogenic impacts. The intrinsic growth rate of the deterministic matrix based on vital rates from Coats Island (λd=1.0102), as well as the stochastic growth rate (λs=1.0098, 95% C.I. 0.9969-1.0226), matched observed population trends. Hunting mortality reduced population growth rate by 0.020 (0.012-0.039), oiling mortality reduced population growth rate by 0.025 (0.012-0.039). Combined these sources reduced the population growth rate by 0.047 (0.033-0.610). Although thick-billed murre populations are stable or slowly growing in eastern Canada, anthropogenic sources of mortality are reducing the ability of the population to grow, and increase vulnerability in these populations to changes in their environment and other pulse perturbations. Our modeling technique could be used to assess specific anthropogenic impacts on populations where a vital rates and numbers killed are known, but no long-term trend information is available. 相似文献
98.
Understanding the effects of oil contamination on the composition and function of soil microbiota entails investigation of the effects of a mixture of hydrocarbons at the community level in a complex environmental matrix. One approach to this difficult problem is to ally a community-level fingerprinting approach with bioassays that have a physiological or functional implication. Two contrasting refined oils (paraffin and motor oil) were used to contaminate soil microcosms, and a simulated bioremediation treatment with nutrient-addition was applied. The indigenous microorganisms were monitored over 103 d using complementary community-level techniques (carbon source physiological profiling using Biolog® microplates, and phospholipid fatty acid (PLFA) profiling). Changes in the toxicity of the applied oils were monitored using luminescent bacterial bioassays, including Vibrio fischeri and a hydrocarbon-degrading Pseudomonas putida strain. Distinct shifts in microbial community structure and C source utilization profiles were observed as a result of oil contamination. There was some evidence that bioremediated soils were returning to control values by the end of the experiment. This was supported by the bioassay results which showed an initial increase in toxicity as a result of the oil addition which had then decreased by the conclusion of the experiment. The two oils exhibited markedly different toxicity towards the bioassay organisms, with species-specific differences in response. This oil-specific difference was also found in the PLFA profiles which showed the two oil types selected different microbial communities. 相似文献
99.
100.