Clonal propagation of Pterocarpus santalinoides L'Hér. ex DC.: the effect of substrate,cutting type,genotype and auxin

Pterocarpus santalinoides is a multipurpose tree species, native to Africa and South America. However, excessive pruning for fodder is jeopardising its seed production leading to poor regeneration in the Sahel region. Efficient vegetative propagation techniques may overcome this concern. To address this issue, four experiments were conducted to determine the effects of substrate (Experiment 1), cutting type (Experiments 2 and 3), genotype (Experiment 4) and auxins (Experiments 1, 2, and 4) on rooting ability in a non-mist propagating unit in Mali. Among the four tested substrates, no significant differences were found in rooting parameters, including the percentage of rooted cuttings, the number of roots and secondary roots per rooted cutting, and the length of the longest root per rooted cutting. Semi-hardwood cuttings rooted significantly better than softwood cuttings with a higher percentage of rooted cuttings (31.7?±?6.5% vs. 9.2?±?2.7%), greater number of roots (8.2?±?4.8 vs 1.5?±?0.7), greater number of secondary roots (16.7?±?4.2 vs 4.6?±?1.8) and longer root length (17.8?±?12.0?cm vs 2.3?±?1.0?cm) per rooted cutting. In addition, one-node cuttings cut below the second and third nodes, respectively, had the highest rooting success (88% and 90%, respectively) followed by cuttings cut below the fourth node (68%) and the first node (62%). Significant differences in the percentage of rooted cuttings were found among 12 randomly selected genotypes with rooting varying from 2% to 75%.The results also showed that auxin application, especially IBA, had a significant effect on rooting success, the number of roots and secondary roots per rooted cutting. Single-node cuttings, and cuttings of 10?cm length with multiple softwood and semi-hardwood nodes, can be used with or without auxin treatment for successful clonal propagation of P. santalinoides. The results of the present study indicated that P. santalinoides is amenable to clonal propagation using low-cost propagators and sand-based rooting media.     

免耕覆盖播种机工况报警系统的研制

研制了免耕覆盖播种机工况报警系统。该系统完全采用数字电路,监测精确,灵活易用,便于功能扩充。通过调整系统阻容参数,可用于不同作物的播种监视。同时开发了基于标准PC的自动测试系统,可为报警器的研制与生产提供检测数据。     

打穴播种机结构参数和工作参数的优化设计

对于不同的玉米种子,以重播率最小为目标对铲式玉米精密播种机的垂直倾角β、水平倾角γ及播种速度υ三个参数进行了计算机辅助优化设计。根据优化计算结果,设计了铲式玉米精密播种拖肥机。     

杉木无性系扦插苗产量和质量的变异与相关分析

杉木无性系扦插试验结果表明，秋季扦插平均成活率８３％；比春、夏、冬季扦插平均成活率分别高５３％、６９％和６０％，１０２个无性系１年生秋插苗平均成苗率８１％，苗高２９．５％厘米，地径４．１毫米，直立率５９．２％，反映秋插苗质量的苗高、地径、直立率等性状受较强的遗传控制且遗传变异幅度较大。秋插苗直立率与成苗率、同、地径之间存在极显著的遗传正相关，根据直立率进行间接选择，入选１０个无性系的成活率，成苗率     

锥面麻花钻横刃廓形及其几何角度分析

横刃对麻花钻的切削性能具有十分显著的影响,这种影响与横刃的廓形及其几何角度分布有关。而横刃的廓形及其几何角度分布又是由钻尖的几何参数决定的.本文在建立起精确的横刃数学模型的基础上,给出了根据任意选定的钻尖几何参数精确、迅速地求解横刃廓形及其几何角度分布的计算方法和公式.通过计算机分析,揭示了横刃廓形及其几何角度分布随钻尖几何参数的变化而变化的规律。     

2BS-1200型水稻工厂化育秧播种机的研制

针对我国水稻育秧生产现状，在吸收国内外先进技术的基础上，研制了一种半机械化水稻育秧播种机，以满足广大农场、农村、连队等小面积水稻种植户对水稻育秧设备的需求。     

气流式集中排种系统中排种定量器的设计

根据气流式集中排种系统的播种要求,通过对普通外槽轮排种器的研究,设计了能够满足"一器多行" 排种的大播量外槽轮排种定量器;由压缩弹簧和调节手柄组成的播量调节装置能准确控制阻塞轮的位置,从而改变外槽轮的工作长度,达到能够准确调节播量的目的.与一般外槽轮排种器的播量调节装置相比,播量调节方便、准确且耐用,为进一步研究气流式集中排种系统打下基础.     

不同浓度外源过氧化氢对小菊扦插生根的影响

以小菊"东莞红"为试验材料,用0、50、100、200、500和1000μmol·L-1不同浓度外源H2O2对小菊插穗处理,观测插穗生根的发生和生长,测定叶片过氧化物酶(POD)和多酚氧化物酶(PPO)活性的变化。结果表明:外源过氧化氢处理对小菊插穗生根有明显的浓度效应,适宜浓度的外源过氧化氢能促进小菊插穗生根以及根的生长,过氧化氢浓度在50-500μmol·L-1的处理能促进插穗生根和根的生长,降低叶片POD活性,提高PPO活性,其中200μmol·L-1为最适宜浓度。     

大果无刺沙棘嫩枝扦插配套技术研究

对大果无刺沙棘嫩枝扦插育苗过程中相关的施肥、移植等配套技术进行了试验研究,结果表明：施肥对大果无刺沙棘扦插苗的生长影响显著,以钼肥为例,1%施肥浓度和蘸根处理的苗木生长效果最好,氮、磷、钾营养元素的配比为1∶0.4∶1最佳;7月1日以前（15～22d扦插苗）移植的苗木生长质量较好;3～5cm根长移植效果较好;裸地扦插苗成活率高,生长好,抗性强。     

银中杨扦插繁殖技术初探

银中杨是具有很高观赏价值的杨树品种之一,苗木繁育上有一定难度,为提高银中杨扦插育苗成活率,试验采用清水浸泡、IBA(吲哚乙酸)及NAA(萘乙酸)3种方法进行银中扬生根处理。结果表明:硬枝扦插中覆地膜配合NAA100mg·L-1处理效果最好,扦插成活率达88%;软枝扦插中IBA50mg·L-1处理的扦插成活率86%。