苹果梨花芽孕育期生长锥细胞超微结构的观察   总被引：1，自引：0，他引：1  

郭金丽  张玉兰  郝喜龙 《果树学报》2001,18(4):213-216

利用透射电镜对苹果梨花芽孕育期芽内生长锥细胞进行了观察，结果显示，在花芽孕育形成的过程中，生长锥细胞的超微结构发生了一系列变化：蛋白体和脂类小滴逐渐增加；核外膜向外延伸到胞质中与内质网相连，其上分布的核糖体增多；线粒体和内质网数目丰富且分布均匀；核糖体大量游散在胞质中；质体呈浅裂，中央缢缩；微管分布于靠近质膜处等。以上超微结构的变化表现出细胞旺盛分裂和分化的特点，反映了花芽孕育过程中的细胞学特征。  相似文献   

箭舌豌豆不同器官对种子产量的贡献     

冯文强  甘炳成 《草业科学》1995,12(5):15-17

研究了箭舌豌豆不同器官对种子产量的贡献，结果表明：箭舌豌豆种子利用花后光合产物较多，不同器管对箭舌豌豆种子产量的贡献是复叶〉茎〉托叶，叶片对种子产量的贡献与其所在位置有关，花后叶因离荚果较近，其光合产物易于向荚果运输。  相似文献   

Significance of local immunity in hen reproductive organs     

Yukinori YOSHIMURA 《Animal Science Journal》2004,75(3):183-191

The current paper describes aspects of local immunity in the ovary and oviduct, and the significance of immunity to reproductive functions in hens. The immunocompetent cell populations in the ovary and oviduct change with a positive correlation to sexual activity, and gonadal steroid is one of the key factors in the increase. Local immune responses mediated by major histocompatibility complex class II and T cell subsets occur in response to infection by Salmonella enteritidis, which may contaminate eggs. In the ovary, immunocompetent cells are also suggested to play roles in the regulation of ovarian functions. Macrophages and T cells are likely to enhance the regression of atretic follicles to maintain the ovarian tissue microenvironment. Autoantibodies to ovarian tissues appeared in the hens with low egg laying frequency, suggesting that the auto‐antibodies may be one of the factors in the decline of egg production. In the oviduct, local immunity possibly has a role in the selection of sperm, though the immunoreactions may also affect sperm survival leading to the decline in fertility. The concentration of yolk IgY, which plays a role in maternal immunity transmission, significantly decreases with the aging of birds, whereas it is significantly increased by estrogen. Therefore, the immune system plays significant roles not only in defense against infection, but also in the functions of reproductive organs. Investigations on the local immune system in the reproductive organs and factors affecting it are of importance for the production of sterile eggs and improvement of reproductive functions.  相似文献   

雏鸡服用益生素后免疫器官指数及局部体液免疫球蛋白相对含量的动态变化   总被引：18，自引：0，他引：18  

杨玉荣  郑世民  刘晶  马春全 《畜牧兽医学报》2005,36(4):352-356

用商品益生素和自制益生素分别灌服1日龄雏鸡，灌服益生素后1、4、7、10、18d测定胸腺、脾脏、法氏囊的器官指数动态变化，用间接酶联免疫吸附试验(ELISA)方法测定泪液、气管液、胆汁和肠液的IgA、IgM、IgG相对含量的动态变化，结果发现服用商品益生素的雏鸡免疫器官指数在第7天高于未服用益生素的对照雏鸡，上述4种体液的IgA、IgM、IgG相对含量在服用益生素后7～10d高于未服用益生素的对照雏鸡，服用自制益生素的雏鸡上述4种体液的IgA、IgM、IgG相对含量在服用益生素后4～7d高于未服用益生素的对照雏鸡。表明益生素对雏鸡的免疫系统有一定的影响，能够促进免疫器官的生长发育，提高雏鸡呼吸道和消化道局部体液的免疫球蛋白相对含量。  相似文献   

遮穗和去颖下燕麦穗部特征变化和穗部光合贡献率估算     

魏露萍  周青平  刘芳  林积圳  詹圆  汪辉 《草业学报》2023,32(2):110-118

随着探索提高植物整体光合能力相关研究的不断开展，麦类作物穗部器官等植物非叶绿色器官光合潜力挖掘逐渐得到关注。本研究在成都平原秋播美达、贝勒、莫尼卡、摄政王、泰克和甜燕60等6个品种燕麦，设置遮穗、去颖2个试验处理，比较分析了各品种间穗部特征、穗部光合贡献率、颖片光合贡献率和茎光合物质转移率等差异。结果表明，燕麦穗部器官光合贡献率为28.56%～49.05%，其中甜燕60最高；6个品种燕麦的颖片光合贡献率为11.03%～36.88%，茎光合物质转移率为6.65%～35.81%。燕麦穗部器官对籽实增重表现了较高的光合贡献，当燕麦穗部器官光合受到限制时，燕麦单粒种子重和单穗种子数显著降低，尤其是影响双粒小穗数。  相似文献   

E．stiedai感染兔免疫器官内球虫抗原的免疫组化定位     

井波  詹剑峰  吴海莉  赵爱云 《兽医大学学报》2014,(2):236-238

用免疫组化SABC法，对斯氏艾关耳球虫感染后兔肝脏、脾脏和肝门淋巴结中球虫抗原的分布进行了观察。结果表明，在肝脏窦状隙、胆管上皮细胞、肝门淋巴结和脾脏内可见到明显的呈棕黄色阳性反应区，表明在这些区域和部位有相应的E．stiedai孢子囊、裂殖子或子孢子抗原存在，且抗原数量以肝脏内最多，其次为脾脏，最少者为肝门淋巴结；显微镜下还可见到大量坏死的肝细胞、淋巴细胞以及朗罕氏巨细胞，说明多核巨细胞也参与了对球虫的吞噬和处理过程。  相似文献   

Dynamic change of mineral nutrient content in different plant organs during the grain filling stage in maize grown under contrasting nitrogen supply     

《European Journal of Agronomy》2016

The introduction of new hybrids and integrated crop-soil management has been causing maize grain yield to increase. However, less attention has been paid on the nutrient concentration of the grain; this aspect is of great importance to supplying calories and nutrients in the diets of both humans and animals worldwide. Increasing the retranslocation of nutrients from vegetative organs to grain can effectively increase the nutrient concentration of grain and general nutrient use efficiency. The present study involved monitoring the dynamic change of macro- and micronutrients in different organs of maize during the grain filling stage. In addition, the mobility of different elements and their contribution to grain nutrient content were evaluated in a 2-year experiment under low (LN, no N supplied) and high N (HN, 180 kg N ha⁻¹) supply. Under HN supply, the net remobilization efficiency (RE) of the vegetative organs as a whole (calculated as nutrient remobilization amount divided by nutrient content at silking) of N, P, K, Mn, and Zn were 44%, 60%, 13%, 15%, and 25%, respectively. The other nutrients (Mg, Ca, Fe, Cu, and B) showed a net accumulation in the vegetative organs as a whole during the grain filling stage. Among the different organs, N, P, and Zn were remobilized more from the leaves (RE of 44%, 51% and 43%, respectively) and the stalks (including leaf sheaths and tassels) (RE of 48%, 71% and 43%, respectively). K was mainly remobilized from the leaves with RE of 51%. Mg, Ca, Fe, Mn, and Cu were mostly remobilized from the stalks with the RE of 23%, 9%, 10%, 42%, and 28%, respectively. However, most of the remobilized Mg, Ca, Fe, Mn, Cu, and Zn were translocated to the husk and cob, which seemingly served as the buffer sink for these nutrients. The REs of all the nutrients except for P, K, and Zn were vulnerable to variations in conditions annually and were reduced when the grain yield and harvest index were lower in 2014 compared with 2013. Under LN stress, the RE was reduced in P and Zn in 2013, increased in Cu and unchanged in other nutrients. The concentration of these nutrients in the grain was either unchanged (P, K, Ca, Zn, and B) or decreased (N, Mg, Fe, Mn, and Cu). It is concluded that grain N, P, K, Mn, and Zn, but not Mg, Ca, Fe, Cu, and B concentration, can be improved by increasing their remobilization from vegetative organs. However, enhancing the senescence of maize plant via LN stress seems unable to increase grain mineral nutrient concentration. Genetic improvement aiming to increase nutrient remobilization should take into account the organ-specific remobilization pattern of the target nutrient.  相似文献   

Content and distribution of different phosphorus forms in broiler chickens          下载免费PDF全文

X.‐K. Li  J.‐Z. Wang  C.‐H. Zhang  X. Li  C.‐H. Tang 《Journal of animal physiology and animal nutrition》2016,100(2):271-278

To understand the background value of phosphorus in chickens, the quantitative distribution of different phosphorus forms, including total phosphorus (TP), free phosphate (FP) and phospholipid (PL), in viscera, blood and bones of broiler chickens was investigated. Results showed that phosphorus contents exhibited significant differences in different parts of chickens. TP content of breast and thigh meat was over 5.0 g/kg, in which most of the phosphorus was in the form of water‐soluble phosphates. TP content in viscera was higher than that in meat, and spleen was observed to contain the highest amount of phosphorus (10.0 g/kg). In all tested organs, FP and PL contents in liver were the highest, ranging between 1207–1989 and 81–369 mg/kg respectively. TP content in chicken bone was in the range of 52 716–136 643 mg/kg, and FP content in the bone was relatively lower than that in chicken meat.  相似文献   

Is partial root-zone drying an effective irrigation technique to improve water use efficiency and fruit quality in field-grown wine grapes under semiarid conditions?     

M.L. De la Hera  P. Romero  E. Gómez-Plaza  A. Martinez 《Agricultural Water Management》2007

We investigated the effects of partial root-zone drying (PRD) applied at different periods on leaf water relations, vegetative development, fruit yield, must and wine quality in wine grapes (Vitis vinifera L. cv. Monastrell) during a 3-year field experiment in order to determine the importance of the timing of PRD application on physiological and agronomical vine response under semiarid conditions. Two irrigation treatments were applied: conventional drip irrigation (CI) and PRD. Both treatments received the same annual water quantity. Each year the PRD treatment was applied at different periods of the growth cycle. In 1999 PRD was applied from veraison to harvest (end July–early September); in 2000 from fruit set to harvest (mid June–early September); and in 2001 PRD from budburst to harvest (mid April–early September). Leaf water relations and gas exchange during the experimental period were not significantly affected by PRD treatment. In 1999 and 2000 there was no significant treatment effect on vegetative development, yield or fruit quality. However, in 2001 (when PRD was applied from budburst to harvest), reproductive and vegetative development was clearly altered in PRD vines. Fruit set percentage and vegetative development (shoot length, pruning weight and primary and lateral leaf area) were significantly increased in PRD vines compared to CI. This resulted in both higher yield (kg per vine) (43%) and water use efficiency (40%) compared to CI vines. Berry number per cluster and cluster weight were also significantly increased in PRD vines. Notwithstanding higher yield in PRD vines and a similar berry size, the must and wine quality was not significantly altered, indicating a higher synthesis and accumulation of photoassimilates and metabolites in the berries of PRD vines. We conclude that there was an positive effect on vegetative and reproductive growth when long-term PRD was applied from the beginning of growing season (budburst), suggesting that early onset of PRD is desirable to intensify PRD response under these semiarid conditions. Nevertheless from these results we need to further investigate the long- and short-term effects of PRD, with moderate water amounts, on vegetative and reproductive development such as flowering and fruit set processes in wine grapes.  相似文献   

Use of saline–sodic waters through phytoremediation of calcareous saline–sodic soils     

M. Qadir  A. Ghafoor  G. Murtaza 《Agricultural Water Management》2001,50(3):197-210

Use of poor-quality groundwater has become inevitable for irrigation to compensate rapidly increasing water demands in many arid and semiarid regions. Salinity and sodicity are the principal soil and water quality concerns in such areas. Many saline–sodic and sodic soils have saline or saline–sodic subsurface drainage waters. Amelioration of these soils needs a source of calcium (Ca²⁺) that can replace the excess exchangeable sodium (Na⁺). Most of these soils, however, contain calcite (CaCO₃) of extremely low solubility. The native calcite does not supply adequate levels of Ca²⁺ for soil amelioration as do other chemical amendments. Phytoremediation may help ameliorate such soils through cultivation of certain crops tolerant to ambient soil salinity and sodicity. This amelioration strategy works through plant root action to help dissolve CaCO₃ to supply adequate Ca²⁺ without the application of an amendment. During a 3-year field experiment conducted under irrigated conditions, we evaluated phytoremediation against soil application of gypsum and farm manure, and water treatment with sulphuric acid on a calcareous saline–sodic soil (pH_s=8.0–8.4, EC_e=24–32 dS m⁻¹, SAR=57–78, CaCO₃=45–50 g kg⁻¹ for the top 0.15 m depth; Calcic Haplosalids). A saline–sodic water (EC=2.9–3.4 dS m⁻¹, SAR=12.0–19.4, RSC=4.6–10.0 mmol_c l⁻¹, SAR_adj=15.6–18.4) was used to irrigate the rice (Oryza sativa L.) and wheat (Triticum aestivum L.) crops grown in rotation. Active desalinisation and desodication processes were observed in all the treatments. After the final wheat crop, the 1.2 m soil profile EC_e was 7±0.5 dS m⁻¹ and SAR was 15±2 with non-significant treatment differences, indicating comparable soil amelioration effect of phytoremediation with other treatments. Better crop yields were obtained from the manure-treated plots, owing to its annual addition to the soil that possibly improved soil fertility. Phytoremediation needed minimum capital input because no initial investment was made to purchase the amendments.  相似文献