糯玉米自交系、杂交种棒三叶与产量之间相关性分析

通过对15个稳定的糯玉米自交系和所组配的杂交组合棒三叶性状、叶面积及单株产量调查,相关性分析,结果表明:糯玉米无论是自交系还是杂交种,棒三叶中下位叶最长、上位叶最宽,棒三叶叶面积大小差异不大.亲本与杂交组合棒三叶叶面积显著相关,相关系数r♀=0.988^**r♂=0.990^**;杂交组合棒三叶叶面积与单株产量极显著相关,相关系数r=0.996^**;6对正反交组合中,母本棒三叶叶面积大的杂交组合棒三叶叶面积大,产量高;反交杂交组合棒三叶叶面积偏小,产量偏低.在组配组合时,棒三叶叶面积大的作母本,有利于高产.     

亚麻鲜茎雨露沤制技术的初步研究

雨露麻以其生产方式简单,成本低,不污染环境而被广泛应用,但传统的雨露麻采用人工收获,在多雨季节里原茎保存困难,常发生霉烂。给工农业均造成损失。鲜茎雨露沤麻技术的提出解决了这一问题,同时使沤麻时间提前10天左右,亚麻收获就开始沤制,充分利用了亚麻收获季节的高温和降雨。沤麻速度快,沤麻时间缩短,降低了生产成本,麻率相对提高0.5-1个百分点,纤维强度增加1.2—2.7kg。此项技术对我国雨露麻的发展具有一定的指导意义。     

密度对亚麻纤维细胞发育的影响

本文研究了密度与亚麻纤维形成发育的关系 ,结果表明 :亚麻植株横切面上的纤维细胞数无论密度如何变化 ,均以中部最多 ,下部次之 ,上部最少。纤维细胞大小 :下部最大 ,中部次之 ,上部最小。在快速生长期以前 ,茎中部的纤维细胞数量随密度的增加而增加 ,而纤维细胞群数则随密度的增加而减少。开花后直到工艺成热期 ,茎中部的纤维细胞均以中密度最多 ,分别为 5 30个和 6 6 2个 ;纤维细胞群数则以其最少。     

Manipulation of tuber-size distribution of a potato crop

Summary Tuber-size distribution is regulated by many diverse, interacting mechanisms and is therefore difficult to understand and manipulate. It is determined by plant density, number of stems per plant, number of tubers per stem, and yield. Seed size and plant number per unit area are easy to control, but stem number is affected by less controllable factors. Interactions between stems of different types are important for tuber-size distribution. The hormonal regulation of stolonization and tuberization is still unknown, but under the conditions of north-west Europe the process of tuber set (which is also poorly understood) makes a greater contribution to the final number of tubers than tuberization. The total yield is also relevant, because it affects both the average tuber size and its variation. Tubers on the same stem differ in timing, rate and duration of growth. The resulting hierarchy in sink strength is not consistent over time. Several mechanisms are suggested for this hierarchy.     

钾肥对甜玉米籽粒品质和茎秆含糖量的影响

本文研究了钾肥对甜玉米籽粒多种营养成分和茎秆含糖量的影响.结果表明:①增施钾肥可提高籽粒多种营养物质含量和茎秆含糖量,但过量施钾反而产生抑制作用.②籽粒淀粉含量的变化趋势与蛋白质、赖氨酸、脂肪和糖相反,当前者含量较高时,后者含合较低.③籽粒中不同营养物质的代谢对钾反应的敏感程度不同,其强弱的顺序为总糖>赖氨酸>脂肪>蛋白质.④因施钾量的多少茎秆含糖量变化很大,当施量较少时,与籽粒蛋白质、赖氨酸、脂肪和糖一样,随施钾量的增加而增加;当籽粒中蛋白质、赖氨酸、脂肪和糖的含量均达最高或较高值时,茎秆含糖量较低;过量施钾籽粒蛋白质、赖氨酸、脂肪和糖的合成受到抑制而茎秆含糖量较高.适量增施钾肥可提高甜玉米营养物质含量,调节各物质比例,达到改进品质之目的.     

碳源对水稻褐变穗病原菌分生孢子萌发的影响

论述了不同碳源和同一碳源不同浓度对水稻褐变穗病原菌分生孢子萌发的影响,结果表明,在供试的10种碳源中,以麦芽糖为碳源,分生孢子萌发率最高,并且适宜分生孢子萌发的麦芽糖浓度范围为1%～4%,麦芽糖浓度为3%时,分生孢子萌发率最高。     

对11份抗逆棉花种质资源的主要性状分析

为有效利用棉花种质资源,对11份抗逆种质资源的主要产量性状、纤维品质性状以及抗虫性进行分析鉴定.结果表明:这11份材料各性状间的变异系数为0.04％～26.09％,变幅较大,其中单铃重、果枝数、单株成铃数和籽棉产量变异系数较大,分别是11.44％、11.22％、20.13％、26.09％;籽棉产量的平均值为2842.9...     

六安瓜片机械化生产工艺的研究

六安瓜片是我国著名的特种绿茶之一。根据瓜片在制造过程中形质转化的规律及其条件,对传统的手工工艺进行了改革,并运用现有制茶机械,实现了制造过程的机械化。机械制茶和手工制茶在工效、生产成本和成茶品质等方面的大量研究表明,前者较后者工效提高20倍,生产成本下降50%以上,成茶外形接近手工瓜片,内质达到或超过手工瓜片,从而为瓜片生产开拓了新的途径。     

Effects of agricultural use of municipal composts

In Switzerland over 2 million tons of solid municipal waste are produced every year. On average, this is equal to one kg per inhabitant per day. More than 75% of the total municipal waste is burned and most of the generated energy is utilized. Only 3% of the total municipal waste is composted normally together with dewatered sewage sludge. The largest fraction of the municipal compost is utilized in vineyards. The beneficial effects of organic matter, nitrogen, phosphorus and calcium and possible harmful effects of heavy metals present in municipal compost on soils are discussed. Constructive suggestions for curative and preventive measures to reduce the metal content of composts and to avoid the problems of irreversible enrichment of heavy metals in soils are discussed.     

Survey of microbial quality of drinking water in rural areas of Kashan-Iran in second half of 2008

The objective of the study is surveying microbial quality of drinking water in Kashan rural areas and determining the rural population that using safe water in terms of microbial quality in second-half of 2008. In this cross-sectional study, microbial quality of water in all rural areas was determined in 3 stages based on 3 parameters as Total Coliforms, Fecal Coliforms and Heterotrophic Plate Count (HPC). The results of this study illustrates that 100.0, 47.71 and 92.99% population in under coverage and non under coverage areas of Kashan Rural Water and Wastewater Company (KRWWC) and all Kashan rural areas, respectively using safe water in terms of Fecal Coliforms and 98.4, 21.2 and 88.00% population in under coverage and non under coverage areas of KRWWC rural areas and all Kashan rural areas, respectively using safe water in terms of Total Coliforms. There is also a meaningful difference in microbial quality between under coverage and non-under coverage rural areas. The results of this study express that the fecal contamination in under coverage rural areas is excellent, but there is a bad condition in non-under coverage areas. Generally, the microbial quality in all Kashan rural areas is approximately equal to national microbial criteria. Its been also illustrated that the role of KRWWC in supplying safe drinking water in terms of microbial quality for rural population is very important.     

亚麻枯萎病发生规律及其综合防治措施

本文从亚麻枯萎病的发生、发展、危害、病原菌传播途径到病害综合防治,进行了系统研究,明确了该病的发生与品种、土壤类型及气象因素等诸方面的关系,为病害防治提供了理论依据;也明确了带菌土壤和种子是该病害主要侵染源和传播途径,用药剂防治效果可达80%以上,同时建立综合防病体系。     

茶树留养叶的光合特性

通过对茶树留养叶光合速率与新梢生育、采摘、打顶、花蕾发育,以及留养叶的着生部位等关系的研究,结果表明,留养叶的光合速率随新梢生育而回升,在新梢长到1芽2叶时达到高峰,采摘能促进新梢萌发,扩大库容量,发挥留养叶的光合潜力,但休止前打顶会降低留养叶的光合效率;采摘时留养鱼叶的光合功能与正常叶相近,留2叶与留1叶光合源能力相近,主梢留叶比侧梢留叶光合能力强;着蕾可提高留养叶的光合速率,着蕾越多,增加越大。     

爆裂玉米爆裂性状的遗传和相关分析

以9个爆裂玉米自交系,采用完全双列杂交,对36个组合F1的5个性状进行了遗传力、基因效应及其相关分析.结果表明,选育膨胀倍数和爆花率均高的自交系和组合是可行的;爆花率与总淀粉、直链淀粉呈显著的负相关关系;膨胀倍数与直链淀粉呈不显著的负相关关系;直链淀粉与总淀粉呈不显著的负相关关系.     

玉米高配合力亲本自交系、杂交种棒三叶的性状分析及叶面积的相关性研究

通过对15个高配合力亲本自交系及其组配的8个杂交种棒三叶有关性状及相关性的研究,揭示优良自交系的特征,探索亲本的搭配,予测杂种优势的大小。初步探明,自交系棒三叶中以穗位叶最长,上位叶最宽。棒三叶各叶面积大小差异不大,都起着同等重要的作用。父本的叶面积对杂交种叶面积大小的贡献较大,杂交种棒三叶叶面积和与杂交种单株产量成正相关。     

温度对暴马丁香中齐墩果酸提取的影响

为了保护和有效利用暴马丁香资源,本实验探究温度对超声波提取暴马丁香中齐墩果酸的影响。结果表明:在提取条件为液料比20:1、70%的乙醇,超声功率为300W、超声30min时,超声温度为50℃时提取效果最佳,含量达2.9993%。可供暴马丁香中齐墩果酸的提取工艺提供参考。     

Volume of individual internodes of sugarcane stalks

Sugarcane (Saccharum spp.) is rather unusual among field crops in that it is not the seed that is of economic value, but rather the stalk. Sucrose is extracted from the large stalks that are produced by sugarcane plants. Considering their economic value, it is rather surprisingly that there is very little information concerning the development and size of the individual internodes over the length of sugarcane stalks. The objective of this study was to document internode volume over the sugarcane stalk of four cultivars and to observe changes in individual internode volume later in the growing season and in response to lodging. When harvested in August, the size of the internodes varied in a continuous manner along the stalk with the largest internode occurring at the bottom of the plant at approximately internode #15. One cultivar (CP80-1743) had much less of a decrease in internode volume below internode #15 than the other cultivars, indicating that growth was more concentrated in the lower internodes of this cultivar. Since the internode volume diminished as the apex was approached, much of the harvested material was concentrated in the bottom nodes. Comparison of a mid-season harvest (August) and a final harvest (January) indicated both that additional internodes were added to the stalk and that the size of all internodes increased. That is, plant growth was distributed all along the stalk and not focused on one particular zone. Similarly, the negative impact of plant lodging was uniformly distributed over the entire stalk, although there appeared to be differences in cultivars in the extent to which the growth of the stalk was decreased.     

Use of a model to analyse the effects of continuous grazing managements on seasonal patterns of grass production

The effects of management on the seasonal patterns of production of grass swards under continuous grazing are examined using a previously described mathematical model. For continuous set-stocking it is observed that, if the leaf area index of the sward at turn-out is too low, there may be a sustained reduction in animal intake throughout the season. Under continuous variable stocking, where the sward is maintained at a constant leaf area index, animal intake is observed to follow broadly a pattern determined by the environmental conditions. It is concluded that grass production, in terms of both gross tissue production and animal intake, is not independent of management. Furthermore, no evidence is found to suggest that the seasonal patterns of production undercutting and grazing are the same.     

基于RIL群体的小麦籽粒性状与品质特性关系分析

为了探究预测小麦品质的方法,利用以小麦品种川农17与绵阳11为亲本构建的重组自交系群体为研究材料(共169个家系),分析了其籽粒性状和品质特性及二者之间的关系。结果表明,小麦粒长与降落值、面团形成时间和面团稳定时间呈极显著负相关,粒宽与沉降值、湿面筋含量和面筋指数呈极显著负相关,千粒重与降落值、沉降值、面团形成时间和面团稳定时间呈极显著负相关,容重与降落值、面团形成时间和面团稳定时间呈极显著正相关,与沉降值、湿面筋含量和面筋指数呈极显著负相关。粒长、千粒重和容重决定了降落值总变异的77.9%,粒长和千粒重决定了沉降值总变异的35.0%,容重和千粒重决定了面团形成时间总变异的50.7%,容重和千粒重决定了面团稳定时间总变异的49.3%,粒长、粒宽和容重决定了湿面筋含量总变异的51.0%,容重决定了面筋指数总变异的45.7%。说明在小麦品质育种中,粒长、粒宽、千粒重和容重可作为预测小麦品质优劣的选择指标。     

农产品信息搜寻问题分析

农产品市场信息不完全,是导致农产品市场交易费用高昂的主要原因。从信息搜寻角度论述了农产品市场信息化形成的必要性,通过分析农产品价格信息搜寻问题,探寻农产品市场信息化形成的基本思路。这对推动农产品市场信息化,降低农产品市场交易费用,从而推动农业经济发展具有重要意义。     

地膜覆盖对小麦土壤水热状况及灌浆特性的影响

为探索适合旱地小麦新品种普冰151的高产栽培模式,在关中平原西部杨凌地区550mm降水条件下,对覆膜穴播、起垄覆膜沟播和露地条播小麦的土壤水热状况、灌浆特性及产量进行了比较分析。结果表明,地膜小麦的土壤含水量在越冬至拔节期高于露地条播,有利于冬前形成壮苗和早春返青,拔节期之后覆膜穴播小麦田土壤含水量最低(除0～20cm);覆膜于小麦拔节期前增温、保温效果显著,拔节期后地温较对照有所降低;覆膜穴播和起垄覆膜沟播平均灌浆速率比露地条播分别提高11.9%和5.5%,且能延长灌浆持续期;与露地条播相比,覆膜穴播和起垄覆膜沟播分别增产10.8%和4.9%,差异显著。综上所述,覆膜穴播小麦在保墒、保温及增产方面表现最好,起垄覆膜沟播次之;地膜小麦是适宜半湿润易旱地区小麦高产栽培方式。