赤霉素浓度和温水浸种时间对猕猴桃不同品种种子萌发的影响

以美味猕猴桃‘徐香’、中华猕猴桃‘宜黄2号’、毛花猕猴桃‘赣绿1号’和‘赣绿2号’4个猕猴桃品种的种子为试验材料,设置5个梯度的赤霉素浓度和5个浸种时间进行处理,通过统计种子萌发的发芽率、发芽势和发芽时滞,探讨赤霉素浓度和温水浸种时间对猕猴桃种子发芽的影响。结果表明：4种猕猴桃种子发芽率与发芽势均受赤霉素浓度和温水浸种时间的影响,其中‘徐香’的种子发芽率和发芽势最高,其次是‘赣猕1号’、‘赣猕2号’和‘宜黄2号’。‘徐香’、‘赣绿1号’和‘赣绿2号’、‘宜黄2号’种子发芽率最高所对应的赤霉素处理浓度和浸种时间组合分别为：0.6 g/L赤霉素+30 min温水浸种、0.4 g/L赤霉素+30 min温水浸种、0.6 g/L赤霉素+30 min温水浸种和0.6 g/L赤霉素+60 min温水浸种。不同品种猕猴桃发芽时滞也有一定差异,其中‘徐香’发芽最早,其次是‘宜黄2号’,‘赣绿1号’和‘赣绿2号’开始发芽最晚。     

饲养密度和性比对蠋蝽存活和繁殖生物学特性的影响

蠋蝽是优良的捕食性天敌昆虫,可捕食40余种重要害虫。为明确成虫不同的性别配比和饲养密度对蠋蝽的寿命、繁殖力和后代生长发育的影响,促进蠋蝽的规模化饲养,在室内测定了不同性别配比（雌/雄为4F/2M、3F/3M、2F/4M、6F和6M）和密度（雌/雄为4F/2M和2F/1M;3F/3M、2F/2M和1F/1M）的蠋蝽的存活率、产卵量、无效卵的比例以及后代发育速率和性比等指标。结果显示,不同饲养密度和成虫性别配比对蠋蝽的存活率、产卵量、有效卵的孵化率以及无效卵的比例均有显著影响,但对后代的发育速率和性比无显著影响。2F/2M的蠋蝽30 d内存活率最高（65%）,且无效卵的比例最低（12.68%）,单头雌成虫30 d内产卵量为105.5粒,与产卵量最高的处理1F/1M无显著差异。4F/2M的蠋蝽的卵孵化率最高,为88.05%,但是与2F/2M（81.57%）无显著差异。2F/2M的蠋蝽适合度指数最高（441.14）,而3F/3M的适合度指数最低。结果表明,在高10 cm,直径7 cm的透明塑料杯内饲养蠋蝽成虫时,雌、雄成虫最佳饲养密度和性别配比为2F/2M。选用合适的饲养密度和性别配比可显著提高蠋蝽成虫的繁殖力。     

4种不同性诱剂对玉米草地贪夜蛾诱集作用

为准确掌握草地贪夜蛾成虫发生动态,筛选对当地种群专一性强、灵敏度高的性诱剂,对深圳百乐宝生物农业科技有限公司(BLB)、宁波纽康生物技术有限公司(NK)、江苏宁录科技股份有限公司(NL)、南京新安中绿生物科技有限公司(XAZL)4个厂家生产的草地贪夜蛾性诱剂在江苏盐城市大丰区进行田间诱捕效果试验,探讨草地贪夜蛾性诱剂的使用技术。结果表明:4种不同性诱剂诱芯对草地贪夜蛾的诱集效果存在明显差异。BLB诱芯和NL诱芯可以有效监测草地贪夜蛾成虫田间发生动态,羽化高峰期明显,且峰值日期一致,NK诱芯诱集的成虫虫峰不明显,XAZL诱芯零星诱到成虫,无明显成虫高峰;BLB诱芯监测期内日均诱蛾量、最高单次诱蛾量、总诱蛾量均显著高于其他3种诱芯,其总诱蛾量达136.75头,分别是NL诱芯、NK诱芯、XAZL诱芯的1.47倍、4.76倍、10.52倍;通过对BLB诱芯进行持续30 d和持续60 d的诱捕对比试验,发现BLB诱芯1~30 d内诱捕性能稳定,诱蛾量大,31~60 d内日均诱蛾量、最高单次诱蛾量、总诱蛾量均有所下降且达显著水平,尤其是50 d后诱捕量下降明显。结果表明:BLB诱芯的诱蛾量大,能够明显反映出草地贪夜蛾的羽化高峰期,符合测报要求,更适合本地区草地贪夜蛾的监测,使用该诱芯时建议30 d更换1次。     

Heritability and genetic correlations between rumination time and production traits in Holstein dairy cows during different lactation phases

So far, rumination has been used as a proxy for monitoring dairy cow health at farm level. However, investigating its genetic aspects as well as its correlation with other important productive traits may turn this management tool into a new informative selection criterion. However, scientific evidences on genetic correlation among rumination time (RT) and milk production and milk composition are still scarce. Therefore, the objective of this study was to estimate the heritability of RT across three lactation phases and its genetic correlation with milk production, milk composition and somatic cell count (SCC). Results of our study showed that heritability for RT was 0.34 and was constant across lactation. The mean genetic correlations between RT and milk production and composition traits were 0.07 (milk production), ?0.07 (protein yield), ?0.31 (fat yield), and ?0.32 (fat/protein ratio). The mean genetic correlation between RT and the SCC was 0.05.     

玉米田杂草马唐的生长特性研究

在田间和室内条件下研究了马唐的生长特性。结果表明 ,马唐种子具有短期休眠 ,其出苗的适宜土壤深度为 0 .5～ 4 .0cm ;随着密度的增加和出苗时间的推迟 ,马唐的单株生长量逐渐下降。     

局域网网络环境中的实时通信模型

讨论了局域网网络环境中的实时通信过程的模型。采用Ｗｉｎｄｏｗｓ的时间中断技术建立了通信过程中相应的几个模型：对话建立模型、数据发送与接收模型和对话结束模型，以便用于网络中的实时通信、实时演示和实时讨论。     

输入具有饱和非线性的离散系统闭环稳定性

基于矩阵范数和离散时间系统李雅普诺夫定理，给出了控制输入具有饱和非线性特性的状态反馈控制系统的闭环渐近稳定性判据。     

伐木作业过程中时间统计分析

应用数理统计方法，结合带岭林业局寒月林场伐木作业，对伐木作业过程中的伐木切削时间和林内行走速度（时间）进行了统计分析．结果表明，伐木切削时间是树种和径级的函数，林内行走速度服从正态分布．     

Effect of Foliar Fertilizers on the Growth of Soybean Cultivars1

Foliar fertilizers (FF) applied at the reproductive growth stage was reported to increase soybean (Glycine max L. Merr.) yield in field trials. But yield increases have not been consistent. Field experiments were conducted on Calloway silt loam soil in 1981—1982 to determine the effect of two foliar fertilizer (FF) formulations, 16N + 4P + 4K + 1 S (Hanway) and 12 N + 4 P + 4 K + 0.5 S (Folian), and time of application, 0800- and 1900-h, on the growth of seven soybean cultivars from maturity groups V, VI, and VII. Foliar fertilizers were applied at a rate of 187 L/ha^?1 in water by a backpack CO₂ pressure sprayer at R5 to R6 growth stages. Foliar fertilizers caused no crop injury (leaf burn) when applied at 1900-h but caused moderate injury at 0800-h, which caused a yield reduction. The most significant crop injury was caused by Hanway formulation when applied at 0800-h. Yields were significantly reduced by FF in 1981 but not in 1982. Generally, Folian formulation treatments had higher yields than Hanway formulation treatments, but neither formulation increased yield above that of the untreated plants. The Bragg cultivar exhibited the least amount of crop injury and the most positive yield response to FF. Plant height, 100-seed weight and lodging rates were not adversely affected by the foliar applications. Due to the general lack of consistent yield increases or in some instances yield reduction from FF applications, the formulations used cannot be recommended for use by soybean producers.     

Effect of Relative Sowing Time on the Growth and Yield of the Component Crops in Okra/Maize and Okra/Cowpea Intercropping Systems

The effects of variations in the relative sowing time of component crops in okra/maize and okra/cowpea intercropping systems were examined in 1990 and 1991 cropping seasons. Okra was either sown the same day as, or two weeks before or after maize or cowpea. Intercropping reduced the growth and yield of okra, maize and cowpea relative to their sole crops. However, okra yield was depressed more by maize than by cowpea, especially when okra was sown two weeks after maize. Comparative assessment of okra/maize and okra/cowpea mixtures suggests that it is better to grow okra and cowpea together than intercropping okra and maize because yield advantages were always higher in okra/cowpea (67% and 59% in 1990 and 1991 respectively) than in okra/maize (15% and 29%). The results were discussed in light of competitive abilities of the various components in the mixtures.