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经过多年多点示范,总结出高山秋种马铃薯高产栽培技术。即秋种马铃薯以选择排灌水方便的沙壤土或黄壤土为宜,忌与茄科作物连作;8月上中旬,采用单垄双行双三角形播种,密度5.25万~6.00万株/hm2;合理施肥,注意防治病虫害。 相似文献
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针对名优茶智能采摘中茶叶嫩梢识别精度不足的问题,该研究对YOLOv8n模型进行优化。首先,在主干网络中引入动态蛇形卷积(dynamic snake convolution,DSConv),增强模型对茶叶嫩梢形状信息的捕捉能力;其次,将颈部的路径聚合网络(path aggregation network,PANet)替换为加权双向特征金字塔网络(bi-directional feature pyramid network,BiFPN),强化模型的特征融合效能;最后,在颈部网络的每个C2F模块后增设了无参注意力模块(simple attention module,SimAM),提升模型对茶叶嫩梢的识别关注度。试验结果表明,改进后的模型比原始模型的精确率(precision,P)、召回率(recall,R)、平均精确率均值(mean average precision,mAP)、F1得分(F1 score,F1)分别提升了4.2、2.9、3.7和3.3个百分点,推理速度为42 帧/s,模型大小为6.7 MB,满足低算力移动设备的部署条件。与Faster-RCNN、YOLOv5n、YOLOv7n和YOLOv8n目标检测算法相比,该研究提出的改进模型精确率分别高出57.4、4.4、4.7和4.2个百分点,召回率分别高出53.0、3.6、2.8和2.9个百分点,平均精确率均值分别高出58.9、5.0、4.6和3.7个百分点,F1得分分别高出了56.8、3.9、3.7和3.3个百分点,在茶叶嫩梢检测任务中展现出了更高的精确度和更低的漏检率,能够为名优茶的智能采摘提供算法参考。 相似文献
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《Communications in Soil Science and Plant Analysis》2012,43(9):1009-1018
Abstract Winged bean (Psophocarpus tetragonolobus) (L.) DC) seedlings of the accession TPT‐1, were grown in a greenhouse with graded, balanced total soluble salt (TSS) concentrations. After 4.5 days, plant height increased quadratically, with a maximum (149 cm) at 3000 ppm TSS. Seedlings were shortest at 1000 and 10,000 ppm TSS, 44.0 and 79.0 cm, respectively. Fresh weight of shoots increased quadratically with greatest weight, 29.03 g, at 5000 ppm TSS. Percent dry matter increased linearly with increasing TSS. Concentration of N, K and P increased quadratically with an increase in the TSS concentration in the growth medium. Concentration of Ca decreased quadratically with increasing TSS. Among the micronutrients, Fe and Mo concentration was quadratic, both elements were highest in the seedlings at 1000 and 10,000 ppm TSS rates. Concentrations of Mn and Zn increased linearly with increasing TSS. Winged bean seedlings at the 1000 to 3000 ppm TSS rates had spindly stems and a sparse, yellow foliage, typical for winged bean seedlings observed in the field during the first 4 to 5 weeks of growth. Seedlings at the 4000 and 5000 ppm TSS rates had sturdy stems and an abundant green foliage. At higher TSS concentrations, 5000 to 10,000 ppm TSS, seedlings had short intermodes and dark green foliage. 相似文献
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针对目前我国竹笋剥皮机械化程度低的问题,设计一种刀削结合滚动摩擦进料竹笋剥皮机。根据竹笋物理特性参数和人工剥笋原理,对竹笋剥皮过程进行力学与运动学分析,确定了影响剥皮效率、损伤率和剥净率的主要因素为刀片安装倾角、剥皮辊转速以及滚筒与剥皮辊轴心高度差,在此基础上,给出了竹笋剥皮机关键部件的设计依据。为获得样机最佳试验物料,以竹笋长度、基部直径作为试验因素进行单因素试验,确定长度为300~320mm、基部直径为29~32mm的竹笋作为剥皮机正交试验物料样本。利用Design-Expert软件设计三因素三水平正交试验,并结合实际工作情况确定最优参数组合,结果表明:当刀片安装倾角为30.12°、剥皮辊转速为229.18r/min、滚筒与剥皮辊轴心高度差为15.43mm时,笋肉损伤率为6.81%,笋皮剥净率为94.59%。在该条件下开展验证试验,得到损伤率、剥净率分别为7.10%、93.22%,与优化参数基本一致,满足剥笋要求。 相似文献
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An in vitro plant regeneration protocol was successfully established in Satyrium nepalense, a terrestrial orchid by culturing immature seeds from unripe fruits. Seeds were germinated on Murashige and Skoog, Knudson C and Knudson C modified Morel medium. The germination of the seeds and development of protocorm was highest in MS medium (86.7%) followed by Knudson C modified Morel medium (74%) and Knudson C medium (61.2%). Among the cytokinins tried for multiple shoot induction from the protocorm, 1-phenyl-3-(1,2,3-thiadiazol-5-yl)-urea (TDZ) was found to be superior. Indole-3-butyric acid (IBA) was effective for inducing healthy roots. Well-developed plantlets were hardened in vermicompost (leaf litter + cow dung 1:1), sand and coconut husk (1:1:1). 相似文献
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The correlation between the anthocyanin concentrations of seven Acer palmatum Thunb. cultivars and the chromaticity values a*, b*, a*/b* ratio, h° and L* was investigated. According to the position of leaves on the branch terminal, middle and base sample leaves were analyzed and the positional effect on the level of the major anthocyanin was estimated. Leaf color was measured with a portable colorimeter and individual anthocyanins were detected with the use of HPLC–MS. Cyanidin-3-glucoside was present in all senescing leaves of Acer cultivars and its content decreased from terminal to base position. Cyanidin-3-rutinoside was identified in lower concentrations in the leaves of all cultivars. Multiple variable analysis was calculated for each of the tristimulus values and two major anthocyanins (cyanidin-3-glucoside, cyanidin-3-rutinoside) in senescing leaves of ornamental Acer cultivars. Correlations were detected between the major anthocyanin (cyanidin-3-glucoside) in analyzed Acer cultivars and all chromaticity parameters. The highest correlation coefficient (0.94) was observed between cyanidin-3-glucoside and a*/b* ratio in cultivar ‘Bloodgood’ and lowest (0.54) between cyanidin-3-glucoside and a* in Acer palmatum Thunb. The correlation between cyanidin-3-rutinoside and chromaticity parameters was not detected in all Acer cultivars, additionally correlation coefficients and statistical significance were much lower. The expression of red color in both senescing leaves and in all-year-red cultivars can be tightly linked with the content level of cyanidin-3-glucoside; the second major anthocyanin does not contribute much to the red leaf color. 相似文献
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Qiaolu Zang Yulian Jiao Xiaomei Guo Fei Zhuge Kaiwun Yeh 《The Journal of Horticultural Science and Biotechnology》2017,92(2):168-174
Callus induction and plant regeneration of Mniochloa abersend via lateral shoots were conducted in this study. Murashige and Skoog (MS) medium supplemented with 1.0 mg/L 2,4-dichlorophenoxyacetic acid (2,4-D) and 1.0 mg/L naphthaleneacetic acid (NAA) was effective for compact callus induction. Remarkably, calli on the MS medium with 0.1 mg/L 2,4-D yielded the highest folds of proliferation (8.01), and showed a high potential capacity to differentiate 1 year after subculture. In addition, the compact calli possessed 100% differentiation rate and generated more shoots that were green and strong in 1.0 mg/L kinetin and 1.0 mg/L NAA. Vigorous roots were generated in the 1/2MS supplemented with 0.5 mg/L indole-3-butyric acid, and the resultant plantlets exhibited 90% survival rate after they were hardened and transplanted. The established regeneration system of M. abersend provides a promising platform for bamboo gene function study. 相似文献