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141.
A pot experiment was conducted in a climate‐controlled greenhouse to investigate the growth, physiology and yield of potato in response to salinity stress under biochar amendment. It was hypothesized that addition of biochar may improve plant growth and yield by mitigating the negative effect of salinity through its high sorption ability. From tuber bulking to harvesting, the plants were exposed to three saline irrigations, that is 0, 25 and 50 mm NaCl solutions, respectively, and two levels of biochar (0 % and 5 % W/W) treatments. An adsorption study was also conducted to study the Na+ adsorption capability of biochar. Results indicated that biochar was capable to ameliorate salinity stress by adsorbing Na+. Increasing salinity level resulted in significant reductions of shoot biomass, root length and volume, tuber yield, photosynthetic rate (An), stomatal conductance (gs), midday leaf water potential, but increased abscisic acid (ABA) concentration in both leaf and xylem sap. At each salinity level, incorporation of biochar increased shoot biomass, root length and volume, tuber yield, An, gs, midday leaf water potential, and decreased ABA concentration in the leaf and xylem sap as compared with the respective non‐biochar control. Decreased Na+, Na+/K+ ratio and increased K+ content in xylem with biochar amendment also indicated its ameliorative effects on potato plants in response to salinity stress. The results suggested that incorporation of biochar might be a promising approach for enhancing crop productivity in salt‐affected soils. 相似文献
142.
Evaluation of Cold Tolerance in NERICAs Compared with Japanese Standard Rice Varieties at the Reproductive Stage
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C. M. Wainaina Y. Inukai P. W. Masinde E. M. Ateka H. Murage M. Kano‐Nakata Y. Nakajima T. Terashima Y. Mizukami M. Nakamura T. Nonoyama N. Saka S. Asanuma A. Yamauchi H. Kitano J. Kimani D. Makihara 《Journal of Agronomy and Crop Science》2015,201(6):461-472
New Rice for Africa (NERICA) is a general name for interspecific rice varieties derived from a cross between the high‐yielding Asian rice (Oryza sativa L.) between locally adapted African rice (Oryza glaberrima Steud.). Eight NERICAs were evaluated for cold tolerance (CT) at the reproductive stage and compared with their O. sativa parents and three Japanese standard rice varieties over 3 years. Cold tolerance was evaluated based on the filled grain ratio (FGR) after cold water irrigation. The FGR was greatly reduced by cold water irrigation. NERICA 1, 2 and 7 had higher FGR (51.9–57.9 %), while NERICA 6, 15 and 16 had lower FGR (6.2–14.5 %). NERICA 1, 2 and 7 were less affected by cold stress, with a 31 % mean reduction in FGR, while NERICA 6, 15 and 16 were greatly affected, with their FGRs being reduced by more than 80 %. NERICA 3 and 4 were moderately affected by cold stress, with about 45 % reduction rate in FGR. FGR significantly influenced the grain weights of the varieties with strong positive correlations (r = 0.83–0.91; P < 0.001), and thus, similar trends in grain weights were observed. Grain weights were reduced by 61.7–96.4 % under cold stress. NERICA 1, 2 and 7 showed significantly better performance than NERICA 3 and 4, while NERICA 6, 15 and 16 performed poorly under cold water irrigation. The Japanese varieties Koshihikari (very tolerant) and Ozora (moderately tolerant) were more affected by cold water irrigation than NERICA 1, 2 and 7. On the basis of the mean reduction rate (%) in FGR under cold stress, the varieties were classified as follows: NERICA 1, 2 and 7 as tolerant; NERICA 3 and 4 as moderately tolerant; and NERICA 6, 15 and 16 as susceptible to cold stress. However, NERICA 7 grain yields were lower under cold stress due to both greatly reduced number of panicles per plant and number of spikelets per panicle. Therefore, NERICA 1 and 2 are suitable candidates for production in the highland regions of East Africa and should be promoted for production. 相似文献
143.
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145.
Brewers' spent grain (BSG) is the insoluble residue generated from the production of wort in the brewing industry. This plant-derived by-product is known to contain significant amounts of valuable components, which remain unexploited in the brewing processes. Therefore, it is essential to develop a more detailed characterization of BSG in order to highlight its potential in developing new value-added products and simultaneously solve the environmental problems related to its discharge. The content of BSG in several biologically active compounds (fatty acids, polyphenols, flavonoids, antioxidant capacity) as well as its volatile fingerprint were assessed and compared with the composition of barley, malt and wheat flour samples. The obtained results emphasized the importance and the opportunities of the re-use of this agro-industrial by-product. 相似文献
146.
优化施肥对春小麦产量、氮素利用及氮平衡的影响 总被引:3,自引:0,他引:3
2009 ~ 2010年,在宁夏引黄灌区分别以宁春11号和宁春16号小麦为供试作物,利用田间试验研究了优化施肥(OPT)和习惯施肥(CON)对春小麦产量、氮素吸收利用和土壤硝态氮累积的影响,表观评估了土壤—小麦体系氮素平衡.结果表明,相对于CK处理,OPT和CON都显著提高春小麦籽粒产量地上部生物量,并促进籽粒N和地上... 相似文献
147.
以微拟球藻为原料,研究微藻水热液化过程中多种参数对水热液化后有机物回收率的影响,包括温度、时间、溶剂比和pH等,从而获得微藻水热液化后有机物的最佳回收工艺条件。结果显示,在室温下进行有机相回收,保证回收溶剂比为20∶1(溶剂/水相不溶物;v/wt)、停留时间为10min、回收pH7,即可达到最佳回收效果。最佳条件下水热液化有机相的回收率为34%左右,且不同的回收温度和pH值对回收的有机相组分均会产生影响。 相似文献
148.
为探明拔节期氮肥运筹对不同滴灌量下冬小麦光合特性及产量的影响,在大田滴灌技术条件下,以‘新冬41号’为试验材料,研究4种拔节期氮肥运筹处理[N0(0 kg/hm2)、N1(90 kg/hm2)、N2(180 kg/hm2)、N3(270 kg/hm2)]对3种不同滴灌量[W1(1500 m3/hm2)、W2(3000 m3/hm2)、W3(3450 m3/hm2)]下冬小麦叶绿素含量(SPAD值)、叶面积指数(LAI)、叶片光合特性及产量的影响。结果表明,在3种滴灌量下各氮肥处理冬小麦拔节至乳熟期叶片SPAD值均呈“先增后降”的变化规律,最大值均在灌浆期;LAI呈现“先增后降”的变化规律,在孕穗期达最大。在同一施氮水平下,滴灌量增加,叶片的净光合速率(Pn)、蒸腾速率(Tr)、气孔导度(Gs)均增加,而胞间CO2浓度(Ci)则降低。滴灌量较低时(W1处理),增加拔节期施氮量能有效提高滴灌冬小麦的有效穗数、穗粒数、千粒重、产量和收获系数;水分充足时(W2、W3处理),增加拔节期施氮量反而不利于产量的提高。综合考虑各项产量指标及氮肥利用效率得出,在滴灌量3000 m3/hm2条件下,拔节期施氮量180 kg/hm2时,滴灌冬小麦籽粒产量较高,氮肥利用率最大,可供生产参考。 相似文献
149.
小麦淀粉颗粒蛋-1(starch granule protein 1,即SGP-1)突变体是选育高直链淀粉含量、高抗性淀粉小麦品种的重要基础材料。SGP-1突变缺失,使胚乳中支链淀粉侧链的延伸受阻,从而使胚乳表观直链淀粉含量相对升高,所制食品的抗性淀粉含量也相应提高,具有重要的保健意义。本研究主要是利用SDS-PAGE方法,检测307份国内外农家种、育成种、高代品系及国内外黑小麦材料的SGP-1(SGP-A1、SGP-B1和SGP-D1)蛋白组成,进而发掘SGP-1突变体;并对突变体材料进行相关农艺性状和品质性状特点的分析,为育种利用及品质改良提供参考。结果共检测到4份SGP-1突变体,均为冬性材料,其中国外材料3份(CH62444、EAP74961和Amigo)、高代品系1份(05黑初8),分别为SGP-A1单缺体,SGPA1和-D1双缺体,SGP-A1和-B1双缺体,以及SGP-A1单缺体。在主要农艺性状方面,EAP74961、05黑初8和Amigo抽穗期与石4185(CK)相近,而CH62444则抽穗较晚,并且3份国外材料植株均较高。这4份突变体材料麸皮中的非水溶性戊聚糖含量相对于水溶性戊聚糖占绝对优势,而胚乳中非水溶性戊聚糖含量与水溶性戊聚糖含量则较为接近,但CH62444、Amigo和05黑初8麸皮中的总戊聚糖含量较高(分别为14.33%,15.20%和12.91%),而EAP74961面粉中的总戊聚糖含量(1.34%)较高。在淀粉组分含量方面,4份突变体材料差异不大。 相似文献
150.
为明确在覆膜滴灌条件下玉米品系(种)主要农艺性状与产量的关系,应用DPS软件对15个玉米杂交品系(种)的主要农艺性状和产量性状进行相关性、灰色关联度等分析,结果表明:籽粒重、穗重、产量的变异系数较大;玉米产量与生育期、籽粒水分含量、穗重、籽粒重呈显著正相关关系;聚类分析可将参试的15个品系(种)划分为3类,第Ⅲ类表现良好,值得进行推广种植。灰色关联度分析表明,玉米籽粒重、穗重、生育期、籽粒水分含量等性状是影响玉米产量的主导因素,在玉米高产育种中,应以其为主攻目标,提高玉米后代的有效选择,加速高产育种进程。 相似文献