基于MRE-PointNet+AE的绿萝叶片外形参数估测算法

为了准确、高效、自动获取植物叶片外形参数,提出一种基于多分辨率编码点云深度学习网络(MRE-PointNet)和自编码器模型的绿萝叶片外形参数估测算法.使用Kinect V2相机以垂直姿态获取绿萝叶片点云数据,采用直通滤波、分割、点云精简算法对数据进行预处理,通过测定的叶片外形参数反演绿萝叶片几何模型,并计算几何模型的...     

Difference in ultraweak photon emissions between sulfonylurea-resistant and sulfonylurea-susceptible biotypes of Scirpus juncoides following the application of a sulfonylurea herbicide

We examined the ultraweak photon emissions from a paddy weed, Scirpus juncoides , to assess the availability of photon emissions for the identification of weed biotypes resistant to sulfonylurea herbicides. The emission intensity from the plant organs increased when treated with a sulfonylurea herbicide in a concentration-dependent manner. The increment in emissions was higher in the sulfonylurea-resistant biotypes than in the sulfonylurea-susceptible biotypes. The difference between the biotypes was greater in the culms than in the roots and remained so through the vegetative growth stage to the flowering stage. This difference was independent of the seed source or mutations in the acetolactate synthase genes of the resistant biotypes. These results suggest that the determination of ultraweak photon emissions can be a useful method for identifying the sulfonylurea-resistant biotypes of S. juncoides.     

松嫩平原扁秆藨草种群生殖株构件表型可塑性及生长分析

采用大样本取样野外实地测定方法,对松嫩平原扁秆藨草(Scirpus planiculmis)种群生殖株的数量性状和生殖分配规律进行了分析。结果表明,在籽实成熟期,扁秆藨草种群生殖株各数量性状具有较大的表型可塑性。变异系数以种子生物量最大,为81.63%;其次为种子生殖分配73.14%;株高最小,为13.11%。扁秆藨草种群生殖株表型可塑性遵循着规律性,即随着株高和株生物量的增加,茎叶生物量呈幂函数增加,花序生物量呈直线增加;生殖分配随着株高和株生物量的增加呈幂函数或指数减少。     

Properties of acetolactate synthase from sulfonylurea-resistant Scirpus juncoides Roxb. var. ohwianus T. Koyama

Properties of acetolactate synthase (EC 4.1.3.18; ALS) from sulfonylurea-resistant (SUR) Scirpus juncoides Roxb. var. ohwianus T. Koyama were studied biochemically and physiologically in comparison with those from sulfonylurea-susceptible weed (SUS). GR₅₀ values for growth inhibition and I₅₀ values for ALS inhibition by imazosulfuron were determined for both SUR and SUS. Imazosulfuron controlled the SUS above 80% at the dosage more than 10 g a.i./ha but did not control the SUR at the even great dosage of 1000 g a.i./ha. The rates required for 50% growth inhibition of the SUR relative to the SUS (R/S ratio) were 271-fold. The I₅₀ value for inhibition of ALS from the SUS was 15 nM, compared to I₅₀ of >3000 nM for inhibition of ALS from the SUR. These results suggest that a resistance may due to an altered ALS that is insensitive to imazosulfuron. The K_m (pyruvate) value of ALS from the SUR was similar to the K_m for ALS from the SUS, suggesting that a mutation resulting in resistance does not change the affinity of the enzyme for pyruvate. The specific activity of the SUR ALS was similar to that of the SUS ALS, which indicates that resistance is not an over-expression of the enzyme. ALS activity from both biotypes was inhibited by isoleucine, valine, and leucine in this order. However, the SUR ALS was less sensitive to inhibition by valine than the SUS ALS.     

盐度和水淹对海三棱藨草种子萌发及幼苗生长的影响

研究海三棱藨草(Scirpus mariqueter)种子和幼苗在盐度和水淹时长作用下的生存机制,为长江口滨海湿地生态修复提供重要的科学依据。通过模拟潮汐控制不同水淹时长(8、10、12、14 h/d)和盐度(0、5、10、15)进行实验,分析其对发芽率、发芽指数、叶绿素、超氧化物歧化酶(SOD)和丙二醛(MDA)等生长生理指标的影响。结果表明:盐度对海三棱藨草种子发芽率、发芽指数和海三棱藨草幼苗MDA影响最大;盐度和水淹时长的交互作用对海三棱藨草幼苗叶绿素和SOD影响最大。在盐度为0、水淹时长为12 h/d时发芽率最高;盐度15是海三棱藨草种子萌发的临界盐度;盐度为10、水淹时长12 h/d分株数最高;叶绿素在0盐度和12 h水淹时长交互处理下最高;SOD总活性在盐度为10、8 h/d水淹时长处理下最高;盐度为10、12 h/d水淹时长处理下MDA含量最低。这说明海三棱藨草在中等盐度(5、10)和中等水淹时长(10、12 h/d)时适应性最强。     

几种大型水生植物对富营养水体中氮和磷的去除效果

采用野外现场试验的方法,研究了芦苇、香蒲、菖蒲、睡莲、水葱、梭鱼草等6种大型水生植物对富营养水体中氮、磷的去除效果。结果表明,水葱和菖蒲对氮、磷的去除效果最好。特别是水葱移栽后易于成活,且适应能力强,值得工程广泛推广。试验还发现,睡莲的生长速度很快,但茎叶脱落后会影响水质。此外,香蒲对藻类的抑制作用明显劣于其他植物。     

模拟遮荫对互花米草和海三棱蔗草种子萌发及幼苗生长的影响

通过绿色薄膜遮光模拟植被遮荫,研究了遮荫对外来种互花米草和土著种海三棱草种子萌发及幼苗生长的影响。结果发现:遮荫对互花米草种子萌发率没有影响,但显著降低了海三棱草种子的萌发率;在遮荫条件下,两种植物幼苗的高度显著增加,单株幼苗的茎叶干重和总干重显著降低,幼苗的1周相对生长率显著降低,其中海三棱草幼苗1周相对生长率降低的幅度明显大于互花米草。这表明,遮荫对海三棱草的幼苗更新和生长具有明显的抑制作用。互花米草群落对海三棱草的遮荫可能是其在长江口竞争取代海三棱草的一个重要机理。     

湖南省藨草属植物资源及其园林应用前景

通过对湖南省蔗草属野生植物资源现状的调查,从观赏特点、生物学特性、园林应用等方面讨论蔗草属植物在生态园林景观中的应用现状及开发潜力。认为蔗草属植物外形独特,生态适应性强,具有很强的园林应用开发潜力,并提出相关建议及展望。     

关于扁秆藨草种群疯长的研究

本文通过试验及简捷的计算,求得扁秆簏草种群的内禀增长率,从而进一步判断扁秆麓草“疯长”的关键时刻,为有效地控制此种恶性杂草的危害提出了可行措施。