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1.
Moringa oleifera Lam. is a member of Moringaceae family which grows throughout most of the tropics, and is native to sub-Himalayan tracts of north west India, Pakistan, Bangladesh and Afghanistan. Moringa seed concentrates 35-45% oil which is considered a great natural cosmetic emollient almost total natural absence of color and odor, and high oleic acid concentration (>73%). To assess their production potential in the Arid Chaco, The Yungas Tropical Forest, Tropical Lowland Forest, and in the Sub-Humid Chaco Ecosystems of South America, a comparative trial was undertaken to determine their seed yield and oil content. Arid Chaco Ecosystem: significant (P < 0.05) difference in seed yields among years were found, with 176.17 and 481.25 kg/tree recorded for 1- and 2-year-old trees, respectively. Sub-Humid Chaco Ecosystems: the difference in seed yield and oil percentage between years was significant (P < 0.05). Comparison between years showed significantly (P < 0.05) higher seed yields, and significantly (P < 0.05) lower oil percentage for the two years old trees, than for the one year old trees. The oil/tree content was significantly (P < 0.05) higher for two years old trees than for one-year-old trees. Yungas Tropical Forest Ecosystem: seed oil percentage was significant (P < 0.05) higher in one-year-old trees than in seeds of two years old trees. Overall: over the tree years, oil percentage was significantly (P < 0.05) higher for seeds produced at the Arid Chaco than at the Sub-Humid Chaco. The seed/tree yields and the oil/tree content were no significantly (P < 0.05) different among the three ecosystems. However, when oil percentage per tree and seed yield/tree were combined trees from Sub-Humid Chaco and from Yungas Tropical Forest yielded significantly (P < 0.05) higher oil content compared to that from Arid Chaco trees.  相似文献   
2.
在半干旱海涂以不同品系菊芋(Helianthus tuberosusL.)为材料进行田间试验,研究了海水灌溉对不同品系菊芋产量构成及离子分布的影响。结果表明:(1)南芋2号根和地上部生物量较其他品系大,南芋5号和南芋3号株高在各浓度海水灌溉下均显著高于其他菊芋品系,而茎粗在各处理下变化不一致,在30%海水灌溉下,南芋1号根和地上部物质积累未受到抑制作用,其他各品系菊芋的根和地上部物质积累受到了一定抑制。(2)各菊芋品系块茎产量差异较显著,在30%海水灌溉下,南芋2号产量显著高于其他品系,各菊芋品系块茎单重在各处理下差异也较显著,南芋1号和2号块茎单重最大,各菊芋品系块茎总糖和菊糖含量差异较显著。(3)随海水浓度的增加,各品系菊芋根、茎和叶的C1-和Na^+含量均增加,但品系间差异较显著,叶片的Na’含量显著低于根和茎的Na’含量。从生物积累量和块茎产量、总糖和菊糖含量及离子分布看,南芋1号和南芋2号较其他品系更适合在半干旱海涂利用适当浓度海水进行灌溉种植。  相似文献   
3.
针对内蒙古大豆主产区,以蒙豆5号品种为试验材料,在旱作条件下,通过对不同施氮、磷、钾量和密度四项农艺栽培措施与产量形成的关系研究,建立了四项农艺措施与产量关系的数学模型.通过对数学模型的优化解析,提出了单产175kg/667m2以上目标产量的优化农艺栽培措施组合方案,即密度以2.05-2.19×104株/667m2、施磷(P2O5)量4.0-5.5kg/667m2、施钾(K2 O)量3.7-4.4kg/667m2、施氮(N)量4.0-4.7kg/667m2.经田间试验验证,模型和提供的优化方案可行,对生产实践具有重要的理论意义和应用价值.除单株荚数随着密度降低而增加外,单株粒数、荚粒数、百粒重及产量均随密度、施肥量增加而呈单峰曲线变化.  相似文献   
4.
播期和栽插密度对协优084主要农艺性状及产量的影响   总被引:1,自引:0,他引:1  
[目的]寻求最适宜的杂交籼稻协优084播期和栽插密度。[方法]在大田小区试验中,设4个播期:5月1日5、月11日5、月21日、5月31日,设5个密度:12万、18万2、4万3、0万和36万穴/hm2,研究不同的播期和栽插密度对协优084主要农艺性状及产量的影响。[结果]随栽插密度的增加,协优084的基本苗、最高苗和有效穗呈上升趋势。协优084随栽插播期的推迟,其穗长呈下降趋势,每穗总粒数、每穗实粒数、结实率、单位面积的总颖花量和产量呈先增加后降低的趋势;随栽插密度的增加,其结实率、千粒重变化不明显,穗长、每穗总粒数和每穗实粒数呈下降趋势。[结论]协优084在长江中下游地区的适宜播期为5月上中旬,中上等肥力水平下的适宜栽插密度为30万穴/hm2。  相似文献   
5.
云南引进帝国百脉根的研究   总被引:2,自引:0,他引:2  
对引进帝国百脉根进行茎叶比、干鲜比、干草产量、营养成分和体外干物质消化率(IVDMD)的测定。结果表明,帝国百脉根含有丰富的营养,分枝期和盛花期粗蛋白含量分别高达28.0%和20.79%,粗纤维含量为13.0%和17.46%,Ca、P 丰富,比例恰当,体外干物质消化率较高而稳定,在分枝期和开花期分别为58.64%和57.25%。因此,帝国百脉根为饲用价值较高的优良豆科牧草,应予以进一步开发利用。  相似文献   
6.
连续两年在盆栽试验条件下,分别在大豆不同生育时期进行水氮处理,试验结果表明:在四个生育期产量均为充足水分 高氮产量最高,与对照相比增产分别为14.3%,24.3%,33.4%,12.5%.特旱 低氮产量最低,分别减产14.1%,39.3%,41.2%,33.1%.干旱和高氮有利于蛋白质的合成,不利于脂肪的合成.与对照相比,不同水氮处理对大豆蛋白质含量影响的范围为从减少1.5个百分点到增加2.0个百分点;对脂肪含量影响的范围是从减少0.8个百分点到增加1.1个百分点.  相似文献   
7.
江苏北部滨海盐土盐肥耦合对菊芋生长和产量的影响   总被引:3,自引:0,他引:3  
在江苏北部滨海盐土进行田间试验,研究了不同盐分含量土壤上盐肥耦合对菊芋生长和产量的影响。结果表明:(1)随着土壤盐分含量的增加,菊芋株高显著下降,菊芋茎粗、块茎产量和地上部生物量随土壤盐分的增加变化趋势与菊芋株高相似。随着氮肥和磷肥施用量增加,菊芋主茎高度显著增加,菊芋茎粗随氮肥施用量增加变化不明显,而块茎产量和地上部生物量随肥料用量增加变化趋势与菊芋株高相似。(2)随着施氮、磷量增加,在各盐分含量土壤上菊芋主茎普遍长高,随着土壤盐分含量的增加,氮和磷效应越明显,菊芋茎粗、块茎产量和地上部生物量在不同土壤盐分含量下,其变化趋势与菊芋主茎高度变化趋势相似。(3)各处理措施均能影响菊芋块茎产量,经方差分析,土壤盐分含量、氮肥施用量、磷肥施用量、盐肥交互作用、氮磷肥交互作用均呈极显著关系,从处理间区别看,影响菊芋块茎产量的主要因素是土壤盐分含量,氮肥和磷肥次之。其中S1N2P3处理所获得的产量最高,此处理土壤盐分含量为0.9~1.5gkg-1,氮肥和磷肥施用量均为60kghm-2。  相似文献   
8.
This study investigated the efficacy of Glomus mosseae and thyme and peppermint oils in controlling bacterial wilt disease (BW) of tomato caused by Ralstonia solanacearum under in vitro conditions and under greenhouse and field conditions. In an in vitro study, we tested nine plant oils against R. solanacearum, and the results demonstrate that only caraway, thyme, peppermint and marjoram oils inhibited the growth of the BW pathogen with differing degrees, thyme oil caused the highest reduction of the growth of the pathogen followed by peppermint and the lowest was caraway and marjoram. We evaluated the effect of thyme and peppermint under greenhouse and field conditions. Under greenhouse conditions, the thyme treatment exhibited the highest disease reduction percentage followed by the thyme + peppermint treatment, while G. mosseae caused the least disease reduction percentage. Under field experiments, thyme oil treatment exhibited the highest ability to reduce the disease by 94.8 and 97.1% in the 2011 and 2012 growing seasons, respectively, followed by the treatment of thyme oil + peppermint oil with the reduction of 89.5 and 82.4%, respectively. G. mosseae exhibited the lowest percentage of disease reduction; however, it caused a greater yield increase percentage during both of the tested seasons.  相似文献   
9.
Field experiments were conducted on a clay soil in entisol to determine the effect of different tillage tools on soil properties, emergence rate index and yield of wheat in Middle Anatolia. There were four different tillage treatments: mouldboard ploughing followed by disc harrowing twice; rotary tillage twice; stubble cultivator followed by a disc harrowing; heavy globe disc twice. The smallest aggregate mean weight diameters and surface roughness were produced by rotary tillage. Decreasing mean weight diameter decreased the surface roughness. There was a significant (P < 0.01) effect of the four different tillage systems on moisture content, bulk density, penetration resistance, aggregate mean weight diameter and surface roughness. Tillage systems had a significant effect on emergence rate and yield of wheat. Emergence rate index and yield of wheat varied from 15.24 to 18.88 and from 3065 kg ha−1 to 4265 kg ha−1, respectively. The greatest emergence rate index and yield were obtained with stubble cultivator followed by disc harrowing treatment.  相似文献   
10.
粮饲兼用型玉米青贮产量形成及调控研究   总被引:6,自引:0,他引:6  
朱霞  杨文钰  任万君 《玉米科学》2005,13(2):090-093
试验选用了在四川当地适合作青贮的粮饲兼用型玉米品种川单21、成单22、雅玉8号、燎原青贮玉米2号与从新疆引进的专用青贮玉米品种新青2号作对比试验,研究其产量形成规律及适宜的种植密度与收割时期。结果表明,鲜物质、干物质产量以及果穗产量均以粮饲兼用型玉米较高,其中以雅玉8号表现最优;适宜的种植密度为127500株/hm2;粮饲兼用型青贮玉米的适宜收获期在抽丝后35~42d,专用型青贮玉米新青2号在抽丝后28~35d。  相似文献   
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