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21.
Aux/IAA 基因家族在植物茎尖发育过程发挥重要作用。为了探究大豆Aux/IAA 基因家族在大豆茎尖发育过程的调控作用,本文以拟南芥Aux/IAA 基因家族蛋白序列为参照鉴定了大豆全基因组Aux/IAA 家族基因,包括63个成员;然后以拟南芥、鹰嘴豆和大豆的Aux/IAA 家族为研究对象,比对这些基因全长氨基酸序列并构建进化树,结果表明三种作物的Aux/IAA 家族成员间亲缘关系差异明显,进化过程中同源重组频率不同;进而利用RNA-seq技术分析东农594(DN)、Charleston(CH)及二者杂交后代的RIL群体的高矮秆池(WH、WS)和F2群体的高矮秆池(JH、JS)的差异表达基因及其功能,共有17个Aux/IAA 基因在3组材料中差异表达。CHvsDN组有15个差异表达基因,JHvsJS组有2个,WHvsWS组只有1个;其中,Glyma.10G180100 在JHvsJS组和WHvsWS组均差异表达,这些结果为进一步研究大豆Aux/IAA 基因家族的功能及调控茎尖发育提供理论依据。  相似文献   
22.
Climate change severely impacts agricultural production, which jeopardizes food security. China is the second largest maize producer in the world and also the largest consumer of maize. Analyzing the impact of climate change on maize yields can provide effective guidance to national and international economics and politics. Panel models are unable to determine the group-wise heteroscedasticity, cross-sectional correlation and autocorrelation of datasets, therefore we adopted the feasible generalized least square(FGLS) model to evaluate the impact of climate change on maize yields in China from 1979–2016 and got the following results:(1) During the 1979–2016 period, increases in temperature negatively impacted the maize yield of China. For every 1°C increase in temperature, the maize yield was reduced by 5.19 kg 667 m–2(1.7%). Precipitation increased only marginally during this time, and therefore its impact on the maize yield was negligible. For every 1 mm increase in precipitation, the maize yield increased by an insignificant amount of 0.043 kg 667 m–2(0.014%).(2) The impacts of climate change on maize yield differ spatially, with more significant impacts experienced in southern China. In this region, a 1°C increase in temperature resulted in a 7.49 kg 667 m–2 decrease in the maize yield, while the impact of temperature on the maize yield in northern China was insignificant. For every 1 mm increase in precipitation, the maize yield increased by 0.013 kg 667 m–2 in southern China and 0.066 kg 667 m–2 in northern China.(3) The resilience of the maize crop to climate change is strong. The marginal effect of temperature in both southern and northern China during the 1990–2016 period was smaller than that for the 1979–2016 period.  相似文献   
23.
Microwave, as a new heat treatment technology, has the characteristics of uniform and fast heating speed. It is an energy-saving technology known for improving oilseed product quality. Its efficiency mainly depends on the roasting power and time. However, the production of high-quality peanut butter using short-time roasting conditions are limited. Herein, we determined an appropriate microwave roasting power and time for peanuts and evaluated its impacts on the quality of peanut butter. Different roasting powers (400 ​W, 800 ​W and 1200 ​W) and times (4, 4.5, 5, and 5.5 ​min) were preliminarily tested. Among them, 800 ​W at 5 ​min was the most suitable. The roasting efficiency was further evaluated using color, sensory, bioactive compounds, storage stability, and safety risk factors of peanut butter produced from four peanut cultivars (Silihong, Baisha-1016, Yuanza-9102, and Yuhua-9414). The pre-treated butter obtained from three cultivars (Silihong, Yuanza-9102, and Yuhua-9414) with moisture content between 5% and 7.2% had a similar sensory score (6–7) as the commercial on a 9-point hedonic scale compare to the other. The color of the pre-treated peanut butter varies statistically with the commercial but remained in the recommended range of Hunter L1 values of 51–52, respectively, for high initial moisture peanut cultivars. The total polyphenol (35.20-31.59 ​± ​0.59 ​μmol GAE/g) and tocopherol (19.05 ​± ​0.35 ​mg/100 ​g) content in the butter obtained from three cultivars (Yuahua-9102, Yuhua, and Baisha-1016) and Silihong respectively, were significantly (P ​< ​0.05) higher than those in the commercial butter. The induction times of all pre-treated butter (19.80 ​± ​0.99–7.84 ​± ​0.07 ​h) were significantly (P ​< ​0.05) longer during storage at accelerated temperature than commercial samples. In addition, no benzo[a]pyrene was found in the pre-treated samples. Collectively, the microwave pretreated peanut butter was superior to the commercial one. These findings provided data support and a reference basis to promote microwave use for peanut butter production.  相似文献   
24.
研究施肥模式对水稻叶绿素含量及荧光参数的调节作用,对提高水稻光能利用效率及籽粒产量具有重要意义。本研究以水稻品种赣929为试验材料,比较长期定位施磷钾肥(PK)、施氮磷钾肥(NPK)、等养分条件下70%氮磷钾肥配合施用30%有机肥(70F+30M)、50%氮磷钾肥配合施用50%有机肥(50F+50M)、30%氮磷钾肥配合施用70%有机肥(30F+70M)条件下水稻叶绿素荧光参数和产量变化特征。结果表明,水稻旗叶叶绿素含量从齐穗期到成熟期呈下降趋势,且表现为30F+70M50F+50M70F+30MNPKPK。水稻叶绿素荧光参数Fv/Fm随水稻生育期的推进呈降低趋势,其中PK处理Fv/Fm值最低,而施氮处理比不施氮处理Fv/Fm值增加了2.85%~4.18%。叶绿素荧光参数qL、ΦPSII在NPK处理中表现为齐穗期较高, 20 d之后显著降低;在50F+50M、30F+70M处理中表现为齐穗期较低, 20 d以后显著增加;在PK处理、70F+30M处理中一直处于较高水平。NPQ变化趋势与qL基本相反。ETR-PAR光响应曲线拟合结果表明, 70F+30M处理ETRmax、?和Ek值在齐穗期和20 d后值均最高。综合看来,等养分条件下配施30%有机肥具有最优的叶绿素荧光指标组合及籽粒产量;而配施超过50%有机肥由于前期热耗散增大使得用于光合作用的光能份额减少,而施用氮磷钾肥处理则由于后期的衰老使得光能利用效率下降。  相似文献   
25.
柑橘大实蝇成虫对9种植物提取物的嗅觉反应   总被引:2,自引:0,他引:2  
为明确对柑橘大实蝇具有引诱或拒避作用的植物精油或挥发物,通过Y形嗅觉仪分别测定柑橘大实蝇雌、雄成虫对橘子精油、橙叶精油、橙花精油、柠檬桉精油、薄荷素精油、栀子花精油、D-柠檬烯、芳樟醇和月桂烯的选择率。结果表明,柑橘大实蝇雄虫倾向于选择橘子精油、橙花精油、D-柠檬烯、柠檬桉精油、栀子花精油,雌虫倾向于选择芳樟醇和柠檬桉精油。柠檬桉精油对柑橘大实蝇雌虫和雄虫均有显著的引诱作用,雌虫对柠檬桉精油的选择率为52.38%,雄虫的选择率也达到了50%。本研究为开发对柑橘大实蝇雌、雄成虫均具有引诱作用的引诱剂提供了一定的理论参考。  相似文献   
26.
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   
27.
氮肥减量条件下间作绿豆压青对甘蔗生长及氮代谢的影响   总被引:1,自引:0,他引:1  
以甘蔗单作常规施氮量为对照(CK),设氮化肥减量20%+间作绿豆压青(A)、氮化肥减量40%+间作绿豆压青(B)和氮化肥减量60%+间作绿豆压青(C)3个处理,通过测定甘蔗农艺性状、蔗茎产量和甘蔗叶片氮代谢相关生理生化指标,研究氮肥减量条件下间作绿豆压青对甘蔗生长及氮代谢的影响。结果表明,间作绿豆影响新植蔗分蘖,分蘖率显著低于CK,但对甘蔗有效茎数影响不显著。新植蔗产量表现为A>B>CK>C。氮化肥减量条件下间作绿豆压青对宿根蔗发株率、株高、有效茎数、甘蔗茎径有促进作用。宿根蔗蔗茎产量表现为A>B>C>CK。2年的甘蔗蔗糖分含量表现为C>B>A>CK。氮化肥减少20%条件下间作绿豆压青对提高甘蔗叶片谷氨酰胺合成酶、硝酸还原酶活性和游离氨基酸、可溶性糖含量有促进作用。综合甘蔗农艺性状、蔗茎产量、氮代谢相关指标测定结果和经济效益的表现,试验以氮化肥减量20%+间作绿豆压青的A处理最优。  相似文献   
28.
为探究施氮处理对不同筋型小麦的植株性状、籽粒产量和品质的影响,采用盆栽试验,选用强筋小麦品种中麦578(A1)和中麦5051(A2)、弱筋小麦品种扬麦15(A3)和扬麦24(A4)为供试品种,在施氮量相同的条件下进行底施(B1)和追施(B2)处理。结果表明:在其他栽培措施相同条件下,强筋小麦穗长、总小穗数、千粒重和籽粒产量均优于弱筋小麦,其中A1籽粒产量分别比A2、A3和A4高0.44%、49.81%和15.27%;施氮处理中B2的株高、穗长、穗粒数、总小穗数和籽粒产量均高于B1;不同处理组合中,强筋小麦品种A1B2的植株和产量性状优于其他处理;强筋小麦品种的籽粒蛋白质含量和蛋白质产量均高于弱筋小麦品种,且具有极显著差异(P<0.01)。本试验中强筋小麦品种中麦5051在氮肥追施处理中可以兼顾籽粒产量、蛋白质含量和蛋白质产量。  相似文献   
29.
[Objective] In order to guarantee the quality and safety of cotton products and to explore the feasibility of alternative planting, the contamination condition of the heavy metals in cotton seeds in Hunan province was investigated and evaluated. [Method] Fifty-six cotton seed samples, collected in 6 counties of Hunan province, were collected to determine 6 indicators including cadmium, lead, copper, chromium, mercury and inorganic arsenic contents. This was followed by pollution index calculation, correlation analysis, and cluster analysis. [Results] The range of comprehensive pollution indexes of Junshan district, Anxiang county, Nanxian county, Wangcheng and Dingcheng districts varied between 0.366 5–0.577 0, which belonged to a secure level. However, the single pollution indexes of Hengyang county are relatively high. The comprehensive pollution index of Hengyang county was 0.801 6, meaning a mild pollution level. [Conclusion] The pollution status of cadmium, lead, copper, chromium, mercury and arsenic in Hunan cottonseed samples are generally acceptable. Cotton could be a substitute for rice on contaminated soil.  相似文献   
30.
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