未来升温1.5℃与2.0℃背景下中国玉米产量变化趋势评估

基于ISI-MIP推荐的5个气候模式在4个RCP情景下的模拟结果,筛选21世纪末全球升温最接近1.5℃和2.0℃的气候数据,运用作物模型DSSAT,模拟升温1.5℃和2.0℃背景下中国玉米产量相对于基准时段1985-2006年的变化,揭示了1.5℃与2.0℃升温背景下中国玉米产量变化的空间分布。结果表明：升温2.0℃背景下玉米减产风险明显高于升温1.5℃,未来升温2.0℃背景下中国玉米减产面积比升温1.5℃背景下多6.2%,升温1.5℃和2.0℃背景下中国玉米平均减产幅度分别为3.7%和11.5%;从空间分布来看,升温1.5℃与2.0℃背景下未来中国玉米产量变化在区域分布上大致相似,但未来玉米增产和减产的面积和幅度不尽相同,在北方与西南玉米种植区都有一定的增产区域,其它区域大多以减产为主,其中西北部玉米种植区减幅最大;1.5℃升温背景下北方大部分地区气候条件对玉米生长有利,2.0℃升温背景下北方地区玉米减产也不明显,说明从近期到未来一段时间内,将全球升温控制在1.5℃以内,北方地区玉米仍具有一定增产潜力。     

Long‐term effects of organic manure and manufactured fertilizer additions on soil quality and sustainable productivity of finger millet under a finger millet–groundnut cropping system in southern India

In a 20‐yr‐old long‐term experiment, the impact of continuous application of organic manures and inorganic fertilizers on soil quality and the sustainability of finger millet production was conducted on two cropping systems: finger millet and finger millet–groundnut on an Alfisol of semi‐arid southern India. The study was conducted from 1992 to 2011 at the All India Coordinated Research Project for Dryland Agriculture, UAS, Bangalore, using a randomized block design. The treatments comprised of T₁: control [no fertilizer and no farmyard manure (FYM) applied], T₂: FYM 10 t/ha, T₃: FYM 10 t/ha + 50% of recommended NPK (50:50:25 kg/ha), T₄: FYM 10 t/ha + 100% of recommended NPK and T₅: 100% recommended NPK. Comparison of long‐term yield data between treatments was used to calculate a ‘sustainability yield index’ (SYI), which was greatest for T₄ (FYM 10 t/ha + 100% of recommended NPK), in both rotational (0.68) and monocropping (0.63) situations. Soil quality indices were determined using principal component analysis linear scoring functions. The key indicators which contributed to the soil quality index (SQI) under rotation were organic C; potentially available N; extractable P, K and S; exchangeable Ca and Mg; dehydrogenase activity and microbial biomass C and N. The largest SQI (7.29) was observed in T₄ (FYM 10 t/ha + 100% NPK), and the smallest (3.70) SQI was for the control. Application of 10 t/ha FYM together with NPK (50:50:25 kg/ha) sustained a mean yield of 3884 kg/ha.     

纳米水在小麦×玉米诱导小麦单倍体中的应用

为了研究纳米水处理对小麦×玉米中单倍体诱导效率的影响,将4个小麦基因型与1个玉米基因型进行杂交,杂交后用两种不同的2,4-D溶液(溶剂分别为纳米水和普通水)处理杂交穗.结果表明,纳米水处理的平均诱导效率明显优于对照处理.两种处理的子房膨大率分别为67.43%和61.11%;得胚效率分别为3.89%和2.61%;胚萌发率分别为48.87%和37.50%;单倍体植株获得率分别为28.77%和1.79%;单倍体植株获得效率分别为1.11%和0.11%.t测验结果表明,纳米水处理的单倍体植株获得率和获得效率显著高于对照.由此可见,纳米水处理在小麦×玉米远缘杂交中能明显提高小麦单倍体诱导效率.     

Intelligence control of on-line dynamic gray cloth inspecting machine system module design. I. Tension controller design

Tension is very closely related with fabric inspection quality, as not well controlled tension of gray cloth will lead to stretch, relax or fold of gray cloth, so that no sharpest image can be taken. Now that gray cloth tension and convey speed are related with taking sharp image, so this study attempts to design a gray cloth tension control module, develop the intelligent online dynamic gray cloth defect automatic detection system. Gray cloth tension control module makes direct regulation of structural tension of feed and wind rolls and conveys speed control module by load cell coupled with A/D, D/A signal conversion and two sets of inverters. This study utilized fuzzy control theory to design controller so as to keep surface tension consistency of gray cloth, improve recognition rate of gray cloth defect, so that the system can have high action efficiency. In previous fuzzy controller designs, membership functions were often designed by means of trial-and-error method, which usually cost much time. This study used Taguchi method to make membership function programming, and made main effect analysis to choose a group of optimal membership function combination. Through systematized, efficient experimental design, tension controller designed in this study could stabilize gray cloth tension very soon, and acquire sharp gray cloth image.     

Changes in oocyte and blood plasma osmotic components of ayu, Plecoglossus altivelis Temminck & Schlegel during oocyte maturation

Oocyte maturation in teleosts is characterized by a complex series of cytoplasmic and nuclear changes. The purpose of this study is to present sequential changes in the oocyte constituents and regulatory mechanisms involved in the hydration and osmotic regulation of oocytes during final maturation of ayu, Plecoglossus altivelis Temminck & Schlegel. Oocyte volumes and water contents in ayu (P. altivelis) markedly increased from 0.372 mm³ and 60.5% at the mature stage to 0.712 mm³ and 79.4% at the time of oviposition. In the same period, net increases in total free amino acids and electrolytes were noted, and involvements of these constituents in the water uptake by oocytes are discussed. Moderate oocyte hydration in ayu is accompanied by steady increases in Na⁺, but not K⁺, and these observations are in contrast to results for all other marine teleosts reported elsewhere. In the present study, a steady increase in oocyte Na⁺ during maturation until ovulation pre‐dominantly results from diffusional leakage due to concentration gradients, while at the time of oviposition, both active transport and diffusional pathways play important roles in osmotic regulation in ayu oocytes.