苏南稻区稻麦周年高产高效品种比较分析

[目的]探明苏南稻区主要稻麦两熟品种的生育期、产量及主要性状的表现,及其与耕作制度的关系.[方法]选择苏州地区种植的南粳46、常优5号、常农粳8号等16个粳稻品种和扬麦16号、镇麦10号等9个小麦品种,通过在苏州不同地区进行试验分析了不同粳稻品种和小麦品种的产量和产量结构、生育期和株高等主要性状.[结果]参试粳稻品种间的产量存在极显著差异,小麦品种间的产量无显著差异;粳稻不同播期和生育期与产量的相关性不显著,而小麦不同播期和生育期与产量的相关性达到极显著水平.稻麦高产品种的每穗粒数与产量的相关性极显著,说明稳定每公顷穗数、控制无效分蘖、提高成穗率、增加每穗粒数是稻麦周年高产的重要基础.[结论]针对苏州地区,在选择周年高产高效的稻麦品种组合时,主要考察水稻品种的产量和品质,其次考虑小麦品种的播期和生育期,再结合实际生产的需要合理搭配高产型、高效型或高产高效兼顾型的稻麦品种组合.     

利用玻璃钢对普通温室的改造及成本分析

利用玻璃钢（FRP）优异的性能对普通温室进行改造,可以产生很高的经济效益,具有很大的推广价值。     

Relationship between level of forage intake,blood flow and oxygen consumption by splanchnic tissues of sheep fed a tropical grass forage

Four Polwarth castrated male sheep (42 ± 4.4 kg live weight (LW) surgically implanted with chronic indwelling catheters into the mesenteric, portal and hepatic veins, housed in metabolism cages and offered Cynodon sp. hay at rates (g of dry matter (DM)/kg LW) of 7, 14, 21 or ad libitum, were used in a 4 × 4 Latin square experiment to evaluate the effect of the level of forage intake on blood flow and oxygen consumption by the portal‐drained viscera (PDV), liver and total splanchnic tissues (ST). The portal blood flow and the oxygen consumption by PDV linearly increased at increased organic matter (OM) intake. No effect of level of OM intake was obtained for the hepatic artery blood flow and oxygen consumption by liver. As a consequence, the level of OM intake only tended to directly affect hepatic blood flow and oxygen consumption by total ST. Oxygen consumption was linearly and positively related to blood flow across PDV, liver and total ST. The heat production by PDV and total ST, as proportion of metabolizable energy (ME) intake, decreased curvilinearly at increased ME intake. In conclusion, the oxygen consumption by PDV, but not by liver, was directly related to the level of forage intake by sheep. Moreover, when ingested at levels below maintenance, most of ME was spent as heat produced by ST.     

Yield response of corn to irrigation and nitrogen fertilization in a Mediterranean environment

Productivity and resource-use efficiency in corn (Zea mays L.) are crucial issues in sustainable agriculture, especially in high-demand resource crops such as corn. The aims of this research were to compare irrigation scheduling and nitrogen fertilization rates in corn, evaluating yield, water (WUE), irrigation water (IRRWUE) and nitrogen use (NUE) efficiencies. A 2-year field experiment was carried out in a Mediterranean coastal area of Central Italy (175 mm of rainfall in the corn-growing period) and corn was subjected to three irrigation levels (rainfed and supply at 50 and 100% of crop evapotranspiration, ETc) in interaction with three nitrogen fertilization levels (not fertilized, 15 and 30 g (N) m⁻²). The results indicated a large yearly variability, mainly due to a rainfall event at the silking stage in the first year; a significant irrigation effect was observed for all the variables under study, except for plant population. Nitrogen rates affected grain yield plant⁻¹ and ear⁻¹, grain and biomass yield, HI, WUE, IRRWUE and NUE, with significant differences between non-fertilized and the two fertilized treatments (15 and 30 g (N) m⁻²). Furthermore, deficit irrigation (50% of ETc) was to a large degree equal to 100% of the ETc irrigation regime. A significant interaction “N × I” was observed for grain yield and WUE. The effect of nitrogen availability was amplified at the maximum irrigation water regime. The relationships between grain yield and evapotranspiration showed basal ET, the amount necessary to start producing grain, of about 63 mm in the first and 206 mm in the second year. Rainfed crop depleted most of the water in the 0–0.6 m soil depth range, while irrigated scenarios absorbed soil water within the profile to a depth of 1.0 m. Corn in a Mediterranean area can be cultivated with acceptable yields while saving irrigation water and reducing nitrogen supply and also exploiting the positive interaction between these two factors, so maximizing resource-use efficiency.     

杜洛克猪HMGA1基因多态位点与生长、饲料利用性状的关联分析

试验对HMGA1基因的两个SNPs位点进行分析,研究了HMGA1基因核苷酸多态性与生长、饲料利用性状的关联性。利用大白猪和民猪重测序结果比较发现了HMGA1基因的两个SNPs位点（g.-543 T > C和g.1356 C > T）,利用Sequenom质谱测序平台对杜洛克猪g.-543 T > C和g.1356 C > T位点进行基因分型,并分析该位点多态性与生长、饲料利用性状的关联性。结果发现,杜洛克猪群体g.-543 T>C位点,CT与CC基因型相比,90日龄体重升高了2.15 kg（P<0.05）,30 kg体重日龄降低了3.21 d（P<0.05）,断奶重升高,剩余采食量降低,100 kg体重日龄减少,30~100 kg平均日增重、40~90 kg平均日采食量、40~90 kg平均日增重均降低。杜洛克猪群体g.1356 C>T位点,CC与TT基因型相比,90日龄体重升高了0.37 kg（P<0.05）;平均日采食量降低0.13 kg/d（P<0.05）,100 kg背膘厚降低0.43 mm（P<0.05）,剩余采食量降低了70.42 g（P<0.05）,30 kg体重日龄降低了0.56 d（P<0.05）;40~90 kg平均日采食量降低了0.17 kg（P<0.05）,断奶重升高,100 kg体重日龄增大,30~100、40~90 kg平均日增重均降低;CT与TT基因型结果与上结果类似。结果初步表明HMGA1基因两个SNPs位点的突变有利于杜洛克猪的生长、饲料利用效率的提高。     

MAP3K5基因在畜禽剩余采食量表型调控中的研究进展

随着分子遗传学的发展,已经鉴定出了影响剩余采食量(RFI)的大量数量性状位点和候选基因。有丝分裂原活化蛋白3激酶5(MAP3K5),也称凋亡信号调节激酶1(ASK1),属于MAPK超家族基因之一。目前,已有细胞外信号调节蛋白激酶(ERK)、c-Jun N-末端激酶(JNK)和p38丝裂原激活蛋白激酶(p38-MAPK)这3个MAPK家族成员在哺乳动物细胞中被克隆和鉴定,其主要作用机制是介导3条MAPKs信号通路,从而影响家畜的生长、体型及产奶性状等。课题组在前期对RFI的研究中筛选出与牛剩余采食量相关的MAP3K5基因,但其功能作用尚不明确,笔者在此基础上回顾了该基因的结构、生物学功能,概述了该基因在主要畜禽采食量变异及人类肥胖表型中的功能及作用,并从遗传学的角度重点分析了MAP3K5基因在畜禽RFI表型调控中的可能机制。通过对MAP3K5基因在畜禽RFI表型调控中的研究进展进行综述,期望为后期深入开展MAP3K5基因在畜禽采食量性状调控中的分子机制研究提供思路;对于其他可能通过MAP3K5基因影响畜禽表型的因素(如肠道菌群)有待进一步探讨。     

羽叶决明代料栽培金福菇的研究

研究了羽叶决明（Chamaecrasta nictitans）替代培养料中的麦麸栽培金福菇（Tricholoma lobayense）对金福菇绝对生物学效率,C、N、P、K利用率,培养料失重率,木质素和半纤维素的降解率及呼吸消耗的影响。试验结果表明：羽叶决明替代40％的麦麸栽培金福菇,其绝对生物学效率,N、K、C素利用率及培养料失重率最高,分别为14．51％、27．71％、35．18％、11．60％和52．04％;而羽叶决明替代100％的麦麸时,呼吸消耗、木质素和纤维素的降解率最高,分别为40．60％、69．44％和72．42％。回归分析结果表明,绝对生物学效率,C、N、P、K利用率和半纤维素的降解率及培养料失重率与羽叶决明替代量呈抛物线关系,而木质素、纤维素的降解率和呼吸消耗与羽叶决明替代量呈线性关系。     

作物育种策略与育种效率

本文运用系统科学的观点分析了正确制定和运用育种策略对提高作物育种效率和效益的作用和意义。作物育种工作整体上由育种目标,育种资源(人力、物力、财力),基础研究,育种程序和技术,以及组织管理等五个相互联系的部分组成,是一个系统。制定育种策略,就是要在制定出合理育种目标的基础上,从育种工作五个部分的相互联系性和层次性出发,综合运用育种有关学科的理论知识、育种经验以及各种技术手段对实现育种目标的动态过程或育种整体计划进行优化,并有效地组织实施,以经济有效地育成新品种,提高育种效率、效果和效益。从这种意义上讲,作物新品种选育工作是一项工程,即作物育种系统工程。     

辣椒/玉米间作条件下土壤持水能力和作物水分利用特征研究

通过田间小区试验,在辣椒/玉米间作(10:2)条件下,对土壤的持水性能、土壤贮水量和作物水分利用效率特征研究分析。结果表明:(1)生长期间作辣椒第1行和第5行的土壤饱和持水量显著高于单作的玉米和辣椒,生长期的土壤饱和持水量显著高于盛果期;生长期间作辣椒的平均非毛管持水量比单作辣椒高54.86%,呈显著差异。(2)收获期玉米单作地的土壤贮水量显著高于辣椒单作地;收获期土壤平均贮水量相比播种前增加了64.95%。(3)间作辣椒产量和水分利用效率均为中间行显著高于第1行,与单作无显著差异性;间作玉米的产量和水分利用效率显著高于单作。从水分利用角度来看,玉米和辣椒间作能提高土壤持水性能,提高作物产量,也是提高田间有限水分利用效率的可行途径之一。     

龟纹瓢虫对麦蚜的捕食功能反应及寻找效应研究

试验结果表明,龟纹瓢虫(Propylaea japonica)成虫对麦蚜的捕食效应符合HollingⅡ型模型,为Na=0.7059N/(1 0.013 3N),成虫对麦蚜的寻找效应是随着猎物密度的增加而降低.根据HollingⅢ型功能反应新模型得:Na=75.19exp(-47.53/Nt),在1 d内,1头龟纹瓢虫对麦蚜达到最大捕食量为75.19头,最佳寻找密度为47.53头,在利用龟纹瓢虫成虫防治麦蚜时,益害比可以以1∶50作为参考值.