营养根

The biomass of rice were not affected by partial-root water stress under those three nitrogen forms, but root parameters of sole nitrate supply decreased significantly under water stress compared to non-water stress part. Water stress stimulated the absorption of NO_3~--N. The photosynthesis rate was inhibited by water stress under NO_3~--N supply, but no effects under NH_4~+-N supply.

局部根系水分胁迫对3种供氮形态营养水稻总生物量没有明显影响，但对单供NO_3~--N营养水稻根系的生物量、根系总长、根体积、平均直径以及根表面积的影响最大，均以未受水分胁迫的一侧根系生物量明显高于另一侧。

This paper gives introduction on measures of Rooting- zone restriction. The theoretical basis (Above and below ground correlation、Local root nutrition、Growth redundancy)、Rooting-zone restriction to the growth and development of plants、Rooting-zone re- striction RZ...

本文介绍了园艺作物限根栽培的措施和理论，依据地上和地下相关性、根系局部营养生长冗余、限根对植株生长发育的影响、限根的生理反应和作用机制以及限根技术的应用等方面探讨了其在蔬菜栽培中的应用。

Mycorrhiza is a mutualistic symbiosis between plants and fungi, and ectomycorrhiza is an important type of mycorrhiza.

菌根是一种植物营养根与土壤真菌形成的共生体，在自然界中分布广泛。

Mycorrhiza is a mutualistic symbiosis between plants and fungi, and ectomycorrhiza is an important type of mycorrhiza.

菌根是一种植物营养根与土壤真菌形成的共生体，在自然界中分布广泛。外生菌根真菌是菌根真菌的重要类群，其宿主植物约占陆地植物总数的3%左右。

In filicophytes, there was a relatively high ratio of VA mycotrophy in the eusporangiates, and there was no autotrophic in the eusporangiates; but the ratio of autotrophic was up to 71%, and the ratioes of VA mycotrophic and facultative mycotrophic were low, 15% and 14% respectively in the leptosporangiates.

用碱解离、酸性品红染色法对云南热带、亚热带自然生长和部分移栽到温室中的256种（拟蕨类植物20种，真蕨类植物236种）蕨类植物孢子体的VA菌根状况进行了调查研究，结果发现，在拟蕨类植物中，孢子体只存在兼性VA菌根营养和自养两种菌根营养类型，两种类型，两种类型所占的比例相当；在真蕨类植物中，厚囊蕨类植物VA菌根营养的比例较高（92%），且无自养类型；而在薄囊蕨类植物中，自养型占71%，VA菌根营养和兼性菌根营养所占的比例都不高，分别是15%和14%。

In the fern allies, there was no obviously evolutional trend among the mycotrophic, facultative mycotrophic and autotrophic, however, the evolutionary trend may be from the mycotrophic to facultative mycotrophic, and at last to the autotrophic which got rid of mycotrophism in the filicophytes

在拟蕨类植物中，VA菌根营养、兼性菌根营养和自养之间无明显的进化趋势；而在真蕨类植物中，则由VA菌根营养向着兼性菌根营养到最后摆脱菌根营养而行自养的方向演化

The results showed that structure of root tissues became disorder and appeared void with increase of the N and P concentration; The content of N, P were increased gradually with the N and P concentration increased; activity of POD, SOD and CAT of Vallisneria spirolis were enhanced gradually with increasing the N and P concentration.

研究发现，随营养程度的增加，苦草根的组织结构紊乱，出现空洞；根叶中氮、磷含量都是随营养程度的增加而增高；苦草叶组织的POD、SOD、CAT活性均随营养程度的增加而上升；随培养时间的延长苦草叶组织的POD和CAT活性呈先上升后下降的趋势，SOD活性下降。

The response may change the fate of the turions in the second year,and affect the maintenance of the populations.

在野外池塘中，利用3种不同营养状况的底质研究底质营养盐对菹草生长及养分分配的影响，结果表明：沉水植物菹草面对底质营养盐的胁迫出现了急性的生理生化反应，在生长初期叶片总的可溶性糖含量在肥沃的底质上高于贫营养底质上；根、茎、叶和石芽各构件都具有异速生长现象，并且表现规律不一样；菹草的根冠比随底质营养盐的不同而变化；随着营养条件对菹草生长胁迫加重，根、冠的异速生长愈明显，同时石芽的N∶P和C∶N比率显著受底质营养盐的影响，而菹草叶片和茎N∶P和C∶N比率不受底质肥力的影响，这些响应将改变石芽第2年的命运和影响种群的维持；在胁迫生境下，菹草首先分配资源到无性繁殖体--石芽上以便维持种群的延续，以回避策略应对底质营养盐胁迫。

Inwheat intercropped with soybean not only N situation could be improved butalso P situation could be.2In intercropping,the pH of soybean rhizospherewas decreased by increasing the R-Apase activity,which could decelerate thetransforming and fixing P fertilizer.3In both monoculture and intercroppingsystem,the soil pH of rhizosphere was affected by cropping system at two Plevel which only 0.1-4mm distance from the root surface,but the effect of S-Apase activity in the rhizospher soil by cropping system was less than3mm.In effect,the rhizosphere P was really available nutrient,and applyingP to rhizosphere was effective ways to reduce the P nutrient competition.4Inwheat/soybean intercropping,the peak stage of reduction ability of roots wasthe same as that of the root growth,so that the time compensation appearedin intensity of nutrient absorption.

间套作大豆、小麦、玉米根系Apase的差异又反映出大豆利用土壤磷的潜在能力最大，而玉米最小，可见禾谷类的小麦与大豆间套后不但能改善小麦的氮素营养状况还使磷素营养也得以好转。2）间套大豆根际pH值的下降，导致磷肥施入土壤后形成〓-P的比例显著提高，转化成〓-P等难溶性磷减少，说明间套的大豆能减缓肥料磷在土壤中的转化和固定，减少磷素向无效化方向转化。3）复合群体根际土壤pH值的影响一般只发生在0.1-4mm的根际微区，而土壤磷酸酶的影响供磷与否在距根表3mm以外都无多大差异，说明根际磷才是真正有效磷，根际施磷是解决磷素竞争的有效途径。4）。

A total of 83 endophytic fungi strains were isolated from fresh root samples of the plants growing on rocks or shrubs, and with red-purple lower leaf surface or with green lower leaf surface. The isolated strains were identified into 19 genera.

从附生于石上及生于杂木林或灌丛中、叶背绿色及叶背紫红色的五唇兰植株新鲜营养根段中共分离出83株内生真菌，鉴定为19个属，其中包括培养基筛选实验中分离出的30株14属。

According to the clear water experiment, aeration performance of the new equipment is good with high total oxygen transfer coefficient and oxygen utilization ratio.

曝气设备的动力效率在叶轮转速为120rpm～150rpm时取得最大值，此时氧利用率和充氧能力也具有较高值。

The environmental stability of that world - including its crushing pressures and icy darkness - means that some of its most famous inhabitants have survived for eons as evolutionary throwbacks, their bodies undergoing little change.

稳定的海底环境─包括能把人压扁的压力和冰冷的黑暗─意谓海底某些最知名的栖居生物已以演化返祖的样态活了万世，形体几无变化。