2种蚜虫在蚕豆上适合度的研究

为了明确豌豆修尾蚜Megoura crassicauda和豆蚜Aphis craccivora在蚕豆上适合度的差异,从中选出适合度较高的蚜虫用于天敌昆虫的大规模繁殖,对两种蚜虫在蚕豆上的发育参数进行了观察并建立了生命表。结果表明：2种蚜虫的成虫历期和世代周期差异虽不显著,但豌豆修尾蚜的若虫历期6.66 d显著低于豆蚜的7.86 d。产蚜量曲线中,豌豆修尾蚜的产蚜量在前期虽迅速增加,但2种蚜虫的生殖力参数差异均不显著。存活率曲线中,豌豆修尾蚜在蚕豆上14～30.5 d时的存活率低于豆蚜,30.5 d后开始高于豆蚜,且其整体存活率曲线比较稳定。生命参数表中,豌豆修尾蚜的周限增长率和内禀增长率分别为1.38和0.32,均高于豆蚜的1.33和0.29。综上,相较豆蚜,豌豆修尾蚜在蚕豆苗上的适合度、存活稳定性更高,更适合在蚕豆上大量扩繁,在蚜虫天敌规模化生产中具有一定的应用潜力。     

十个玉米自交系主要数量性状配合力和遗传参数分析

利用10份玉米自交系按不完全双列杂交配成25个组合,对其主要数量性状的GCA、SCA和遗传变量进行估算和分析.结果表明,除穗位高、千粒重、出籽率和子粒产量的SCA外,其余各性状的GCA和SCA都达到显著或极显著差异.H504、同系和82-2A等3个自交系综合性状较优,可组配强优势杂交组合的优良自交系。     

7个玉米自交系主要性状的配合力及遗传参数分析

本文按双列杂交法(D4)分析了7个自交系的生育期、株高、穗位、穗长、穗粗、穗行数、行粒数、秃尖长、百粒重、出籽率、单株子粒重11个性状的GCA、SCA及遗传参数。结果表明：8个性状主要受加性基因效应控制，非加性基因效应作用较少。8112、1302、掖107在我市表现较好，是有利用价值的亲本。8112×1302、8112×岩自38、掖107×86-11、1302×掖107等组合，可在我市示范种植。     

几个玉米自交系主要农艺性状的配合力和遗传参数分析

利用12份玉米自交系按不完全双列杂交配成32个组合,对其主要数量性状的GCA、SCA、TCA和遗传参数进行估算和分析.结果表明:99-78、99-41、99-14、99-6和99-11等自交系的综合性状较优,是组配强优势杂交组合的优良自交系,如99-78×99-41、99-14×99-41;而99-63和99-74等的综合性状较差,需进一步改良方能利用。     

Sound characteristics according to cross-sectional shapes of fibers

In order to investigate the effects of cross-sectional shapes on the sound characteristics of polyester fibers, 10 specimens were woven into a twill structure made of round, hollow, triangular, u-shape, cruciform, and composite cross-sectional (▴/▴, ()/▴,Y y) fibers. Their rustling sounds were recorded, and their sound spectra were obtained from FFT analysis. Physical sound parameters (LPT, ΔL, Δf) and Zwicker’s psychoacoustic parameters of the loudness(Z), sharpness(Z), roughness(Z), and fluctuation strength(Z) were calculated from the sound spectra. According to noncircular cross-section fibers, the hollow shaped fiber had the highest value of LPT, ΔL, loudness(Z), and fluctuation strength(Z). The triangular shaped fiber had a lower value of LPT, ΔL, loudness(Z), and roughness(Z) than those of the round shaped fiber. Among composite cross-section fibers, C1 (▴/▴) and C3 (Y y) had higher values of LPT, ΔL, Δf, and loudness(Z) but C2 (()/▴) had lower values. Also the LPT, ΔL, sharpness(Z), and roughness(Z) values of different denier were similar to each other, but the Δf and loudness(Z) values increased as the denier increased.     

Improvement of okra seed germination by drying within the fruit during development and after-ripening treatment

Abstract

The inverse linear competition model and three non-linear hyperbolic models were tested on two years' results from field experiments with barley and oilseed rape. Densities ranged from 1/9 to 3 times the normal seed rate (i.e. 350 barley plants m^?2 and 100 oilseed rape plants m^?2). A log transformation of both sides was necessary to ensure homogeneity of variance. The best precision of parameter estimates was found using the non-linear hyperbolic model:

where w is the individual plant weight and N is the plant density. A _{N 0} is the dry matter production per plant at a density N ₀, and B is the potential biomass production per unit area under the actual growth conditions. The estimated values of parameters AA _{N 0} and B agreed well with the values actually measured. The computational, as well as the biological, implications of introducing a threshold density, N ₀ are discussed.     

三种杀螨剂对双尾新小绥螨后代生长发育和繁殖的影响

为明确杀螨剂对双尾新小绥螨Neoseiulus bicaudus后代生长发育及繁殖的影响,采用联苯肼酯、三唑锡和哒螨灵对土耳其斯坦叶螨Tetranychus turkestani的致死中浓度处理双尾新小绥螨雌成螨,测定其后代各发育阶段的存活率、发育历期、寿命、雌性比例及繁殖力,构建亚致死条件下双尾新小绥螨后代的年龄-龄期两性生命表并模拟其种群增长模型,分析不同杀螨剂亚致死效应对捕食螨后代的影响。结果表明,联苯肼酯处理能显著缩短双尾新小绥螨后代的未成熟期（4.81 d）,显著延长双尾新小绥螨后代雌成螨的寿命（45.43 d）,且对存活率、产卵前期、雌性比例和净增殖率无显著影响。三唑锡处理降低了双尾新小绥螨后代雌性比例（0.37）并显著降低了其后代净增殖率（15.91）,对未成熟期、产卵前期和雌雄成螨寿命均无显著影响。哒螨灵处理对双尾新小绥螨后代的未成熟期、存活率、雌成螨寿命、产卵前期、和雌性比例均未产生显著影响,仅显著延长了雌雄成螨寿命（51.22 d和44.23 d）。经所建Timing种群模型模拟,3种杀螨剂处理后双尾新小绥螨后代种群均可以继续增殖,经过60 d无限制增殖后,联苯肼脂处理的双尾新小绥螨后代种群数量是对照的1.62倍,达4 976头;哒螨灵处理（2 101头）和三唑锡处理（983头）的种群数量较对照分别减少了31.43%和67.92%。表明联苯肼脂对双尾新小绥螨后代影响较小,是较为安全的杀螨剂。     

凉山半细毛羊几个早期性状遗传参数的估测

利用凉山半细毛羊核心育种场1997-2003年间的育种资料,系谱经过微卫星标记校正后,用MTDFREML软件估测了初生重(BWT,n=1 282)、断奶重(WWT,n=1 000)和断奶毛长(WSL,n=909)三个性状的方差组分和遗传参数。结果表明BWT、WWT和WSL的遗传方差、不相关的随机效应方差(永久环境效应方差)所占的比例较小,残差方差所占的比例较高。三个性状的遗传力分别为0.24、0.06、0.13,相应的遗传相关系数分别为0.87-、0.53和-0.52。     

玻璃钢渔船总体设计中的参数选择

纤维增强塑料渔船──简称玻璃钢（ｆｉｂｅｒｇｌａｓｓ　ｒｅｉｎｆｏｒｃｅｄ　ｐｌａｓｔｉｃ,ＦＲＰ）渔船具有阻力小、自重轻、耐腐蚀、寿命长、易于维修和保养等特点。玻璃钢渔船材质轻巧,特别适用于作业方式较轻缓的渔船（典型的如钓船）,而回避那些作业强度大,对鱼类资源破坏严重的高强度作业方式,因而适应环境和资源保护的需要,正成为现代渔船的发展方向之一。但由于受初始造价偏高及其它技术因素的影响,我国ＦＲＰ渔船进展缓慢,船型不多、数量偏少、经验和统计资料较为缺乏。本文根据设计研究和统计分析的实践经验,提出…     

青海猞猁血液生理生化参数测定

报道了对西宁动物园４只猞猁１７项血液生理生化参数的测定结果。