斜入式穴盘苗移栽手爪工作参数优化及试验验证

为实现低伤苗率下的盘间移栽作业,该文设计了一套斜入式穴盘苗移栽手爪,并对其关键参数进行了试验研究,以期提高移栽成功率。该手爪采用单驱动源下的联动机构实现斜入式取苗方式,可降低对穴苗钵坨的损伤,保证其在提取后有较好的完整性。通过对取苗过程进行分析,得到了影响移栽成功率的关键性因素。以红掌穴苗为试验对象,选取钢针插入点距离、钢针插入深度以及钢针插入角度为影响因素,以穴苗极限破坏力为优化指标,利用响应曲面方法进行优化试验设计。试验结果表明,当钢针插入点距离为11.5 mm,钢针插入深度43 mm,钢针插入角度为14°时,可以达到最大极限破坏力3.89 N。应用此参数组合进行斜入式移栽手爪性能测试验证,试验结果表明优化后的移栽手爪的移栽周期为4 s,移栽成功率可达98%,能够应用到实际生产当中。该研究结果可为盘间移栽领域自动化移栽机的研制与开发提供参考。     

水稻机械化播栽对稻田甲烷和氧化亚氮排放的影响

为探明高产栽培条件下水稻机械化播栽对稻麦两熟农田稻季甲烷(CH4)和氧化亚氮(N2O)排放的影响,以超级稻南粳44为材料,于2011年和2012年在麦秸还田和不还田两种条件下对机械直播、机械栽插、常规手栽3种水稻播栽方式的稻田CH4和N2O排放量和水稻产量进行了比较研究。结果表明,稻季CH4和N2O排放主要集中在水稻生育前中期,移栽至有效分蘖临界叶龄期CH4累积排放量占稻季总排放量的76.49%~91.13%,有效分蘖临界叶龄期至拔节N2O累积排放量占稻季总排放量的33.56%~49.41%。麦秸还田显著提高稻季CH4总排放量(P0.05)、降低N2O总排放量(P0.05),机械栽插的稻季CH4总排放量较常规手栽略减3.25%~9.50%(P0.05),机械直播显著低于机械栽插和常规手栽(P0.05):2011年,麦秸不还田条件下机械直播较机械栽插和常规手栽稻季CH4分别减排15.69%和18.43%,麦秸还田条件下分别减排14.54%和22.66%;2012年,麦秸不还田条件下机械直播较机械栽插和常规手栽稻季CH4分别减排26.63%和32.12%,麦秸还田条件下分别减排30.51%和36.75%。机械直播较常规手栽显著增加稻季N2O总排放量0.16~0.97 kg/hm2(P0.05),机械栽插和常规手栽的差异不大(P0.05)。机械直播的产量水平显著低于常规手栽(P0.05),减产8.43%~10.79%,机械栽插较常规手栽产量降低1.27%~3.49%(P0.05)。稻季的全球增温潜势主要由排放CH4产生,麦秸还田显著提高全球增温潜势(P0.05),机械直播的全球增温潜势显著小于机械栽插和常规手栽(P0.05)。麦秸还田条件下,2011年和2012年机械直播的"单位产量的全球增温潜势"较常规手栽分别减少12.02%和28.71%(P0.05)。上述研究表明,在长江下游稻麦两熟区采用机械直播有利于减少稻季CH4排放,麦秸还田条件下机械直播替代常规手栽能减少稻田排放CH4和N2O产生的综合温室效应。     

小型蔬菜移栽机的改进设计与试验

为满足蔬菜移栽机械化需要,在土槽蔬菜移栽试验基础上,对水稻插秧机改进设计,应用优化设计方法和虚拟技术相结合,完成了取投苗机构、划刀式开沟器和V型覆土镇压器有机组合,可以一次完成开沟,送苗入沟,扶正,覆土,压实等工序。通过三因素三水平的正交试验,获得较优参数组合,即机车前进速度为0.25～0.30 m/s,投苗筒垂直倾角为12°,镇压器的相对位置为10 mm时,移栽效果优异。经田间试验测试,该机具结构简单,通用性好,作业适应性强,各项作业性能指标完全符合农艺要求,为小型全自动移栽机的设计提供参考。     

花卉幼苗自动移栽机关键部件设计与试验

为实现盆栽花卉幼苗机械化移栽作业,减轻人工操作劳动强度,该文对花卉穴盘苗自动移栽机的关键部件进行设计。基于机器视觉技术获取花卉幼苗生长信息,采用区域目标像素统计的方法对幼苗生长状况进行评价,并对优质种苗进行定位,剔除缺苗、劣苗。为满足不同规格穴盘通用性和种苗无损操作要求,设计了弹簧驱动柔性可调的幼苗根部夹持手爪,通过对手爪的力学分析计算,优化其中关键零件的结构参数。移栽机控制系统由PC上位机扩展多路电机驱动节点,以满足多轴控制需要。基于自动移栽机试验平台,对各关键部件进行试验测试,结果表明系统移栽作业效率小于800工作循环/h时,夹持手爪能够对幼苗进行可靠操作,移栽成功率95%以上,此外视觉系统对幼苗识别准确率87%以上。     

虎杖组织培养技术研究

以虎杖带腋芽的茎段为试验材料,研究虎杖组织培养与快速繁殖的适宜条件。试验结果表明,虎杖在MS 6—BA 2.0 mg/L IBA 0.2 mg/L 3%蔗糖 0.7%琼脂培养基上增殖效果最好,培养30 d,增殖倍数达到3.4以上;在1/2MS IBA 0.5 mg/L 3%蔗糖 0.7%琼脂培养基上生根效果最好,生根率100%,平均根长2.0 cm,平均苗高3.5 cm,以圃地表土为基质,在温室大棚内间歇喷雾的移栽成活率达96.25%。     

Tall planting stock for enhanced growth and domination of brush in the Douglas-fir region

Two long-term experiments followed development of planted stock of various sizes, origins, and species. In one experiment, multiyear comparisons of container, 2-0 bareroot, and 3-year-old Douglas-fir transplants showed strong positive relationship between initial height and long-term (10–14 years) growth under a range of site conditions with high probability of brush development. In the other experiment, Douglas-fir, western hemlock, and Sitka spruce were planted in salmonberry disturbed by logging 0 and 4 years previously. Half the seedlings were released with glyphosate 6 months after planting. Hemlock and Douglas-fir bare-roots all grew well if planted in a fresh burn, despite rapid regrowth of salmonberry, but virtually all seedlings less than 60 cm tall except Sitka spruce were killed by 4-year-old salmonberry if not released. Release improved growth of seedlings in the fresh burn by 6%, gaining an average of about 0.6 year toward reaching a height of 6 m. Release improved growth of survivors in 4-year-old salmonberry by 51% in height, 72% in diameter, and 325% in volume at age 12. Sitka spruce grew well until damaged by insects. Hemlock growth was equal to or greater than that of Douglas-fir of comparable initial height. In all comparisons, the probability of being overtopped by brush decreased with increasing initial stock height, and the effect of suppression on growth was also inversely related to initial height. Field planting operations may require special logistic measures for the largest stock types.This is Paper 2706 of the Forest Research Laboratory, Oregon State University.     

Evaluating methods for storability assessment and determination of vitality status of container grown Norway spruce transplants after frozen storage

ABSTRACT

Autumn sown small seedlings for later transplanting into large containers have been introduced in Swedish forest tree nurseries. Containerized transplants of Norway spruce (Picea abies (L.) Karst.) from three Swedish nurseries were frozen stored during the autumn of 2014 to find out storability and post-storage vitality. Seedling storability was determined by measuring electrolyte leakage after freezing shoots to ?25°C (SE L _diff?25), by measurements of dry matter content (DMC) of seedling shoots and by the commercial molecular test ColdNSure?. Vitality of seedlings after storage was determined by measuring the leakage of electrolytes from shoots (SEL), and seedlings were also tested in regrowth tests. All three methods for storability assessment gave similar predictions, except in one case where DMC showed “not storable” for successfully stored seedlings. Our results indicated that young transplants can be successfully short term stored before reaching the target levels for safe long-term storage of conventional seedlings. Early storage of young transplants resulted in low post-storage survival and vitality expressed as root growth capacity and shoot electrolyte leakage (SEL). A prolonged duration in storage generally resulted in lower survival as well as lower root growth capacity and higher levels of SEL, especially for seedlings stored at earlier dates.     

番茄穴盘育苗株型化学调控的研究

在穴盘育苗条件下 ,利用 3种植物生长调节剂对番茄幼苗进行了株型调控试验 ,以便实现适当加大苗龄与壮苗的协调统一。结果表明 :CCC和PP333对控制株高及提高秧苗质量有积极作用 ,浇灌浓度分别以 2 5和 10mg·L- 1的秧苗G值和壮苗指数较高 ,与对照相比 ,根系活力、叶绿素含量、抗寒性等生理活性显著提高 ,体内大量元素的含量增加 ,且抑制后效应均不明显 ,CEPA则效果较差     

单自由度四连杆取投苗机械臂设计

针对目前蔬菜穴盘苗自动取投苗机构结构复杂、制造成本较高等问题,该文设计了一种单自由度开式铰链四杆机构取投苗机械臂。首先通过对钵苗力学特性进行分析,为取苗爪的外形设计提供了依据。其次根据人工取投苗和现有取苗机构的作业过程,制定了取苗机构的设计要求。然后对机构的运动路径和各运动副的运动进行规划设计,最终设计出一种单自由度全机械式的取投苗机械臂,显著降低了成本。试验结果表明:取苗爪抓取点的运动轨迹和设计要求与理论仿真结果相一致,移栽试验中取苗成功率为96.7%,钵体破损率为3.13%,投苗成功率为97.74%,总体成功率为91.32%,机构的可靠性较高。该机构的设计提供了一种全自动取投苗方法,可为开展移栽装备的全自动化研究提供参考。     

蔬菜移栽机气吹振动复合式取苗机构设计与试验

针对我国全自动蔬菜移栽机取苗、投苗机构复杂等问题,设计了一种蔬菜移栽机气吹振动复合式取苗机构及其配套苗盘。设计的取苗机构主要由送苗装置、振动装置和气吹装置等组成,各部分配合完成自动取苗、投苗工作。构建了振动过程中苗盘与钵苗的动力学模型,通过分析钵苗取苗条件,求解出振动过程中影响取苗成功率的3个主要参数:振动频率、振幅以及钵苗基质含水率。综合考虑振动与气吹相结合的取苗方式,以取苗成功率、基质破损率作为取苗效果评价指标,选取钵苗基质含水率、振动器振动频率、吹气气压为试验因素,进行多目标正交试验。试验结果表明:在给定因素水平下,当钵苗含水率为55%、振动器振动频率为36 Hz、吹气气压为0. 45 MPa时,取苗效果最佳,此时取苗成功率为92%,基质破损率为3. 46%。