共查询到19条相似文献，搜索用时 203 毫秒
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杉木种子园无人机辅助授粉效果分析 总被引：1，自引：0，他引：1
采用六轴旋翼无人机(型号SH-X6-10B)进行杉木种子园辅助授粉试验,比较不同飞行高度、飞行速度、授粉介质、花粉与介质配比、不同授粉方法的杉木座果率及作业效率。结果表明:无人机距树梢6~8 m飞行高度授粉的杉木座果率最高,达65.0%;飞行速度2~3 m·s^-1授粉的杉木座果率最高,达67.2%;以滑石粉为授粉介质的杉木座果率最高,达66.0%;花粉与介质(滑石粉)配比1∶50授粉的杉木座果率最高,达66.1%;无人机辅助授粉的杉木座果率比人工辅助授粉提高46.0%,比自然授粉提高117.5%;无人机辅助授粉的山地作业效率是人工辅助授粉的33倍。 相似文献
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Development of water oak stump sprouts under a partial overstory 总被引：2，自引：0，他引：2
A 28-year-old water oak (Quercus nigra L.) plantation was thinned from below to either 254 or 462 stems per hectare to determine the influence of a partial canopy on oak stump sprout development. Sprout clump survival, number of living sprouts in a clump, and height and DBH of the dominant sprout in a clump were measured in years 1–5 and 7 after harvest. By year 7, sprout clump survival under the heavily thinned canopy was 23% higher than under the lightly thinned canopy. Within-clump sprout mortality was not influenced by overstory thinning level, but by year 2 height and diameter increment were 15% and 22% greater, respectively, under the heavy overstory removal. Positive height and diameter growth of dominant sprouts continued under both canopy conditions through year 7, but early benefits of the heavy overstory removal on sprout growth diminished. Additional overstory removal or sprout clump thinning would be necessary to sustain sprout clump survival and sprout growth over extended periods. 相似文献
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通过采用不同方法进行核桃座果率的试验,结果表明：花期喷磷酸氢铵和磷酸二氢钾、在萌芽期去除90%雄花芽,或在伸长期去除60%和90%雄花,可明显提高核桃的座果率,从而提高核桃的产量。 相似文献
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丽江照水梅结果特性调查研究 总被引：1，自引：0，他引：1
照水梅短果枝长度〈3cm的座果率最高,随着母枝长度的增长,着生的短果枝数增多,但照水梅母枝长度与短枝数量以及采果数之间无明显的关系。照水梅结果以二果序为主,平均单果重34.5g,可食率高,自然落果率较低。 相似文献
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笔者采用"云大120"、GA_3、BA-6等不同药剂组合对新生系3号和黔阳无核椪柑进行了保花保果试验。试验结果表明:"云大120"组合对黔阳无核椪柑保花保果效果很好,坐果率达21.10%,最高达25.00%,比喷清水作对照高5.40%;细胞分裂素组合对黔阳无核椪柑保花保果有增效作用,坐果率达30.91%,比对照高1.10%。 相似文献
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短叶省藤和黄藤组培苗造林研究 总被引：1，自引：0，他引：1
造林试验结果表明，黄藤组培苗的适应性与保存率不低于实生苗，其造林的立地、整地、上层林木和种植措施等可与实生苗相同。黄藤组培苗能保持母株优良的生长特性，生长显著快于未经选择的实生苗。同时，组培丛芽苗的第1单芽的茎长生长快于第2单芽的茎长生长。短叶省藤的单芽高度与造林保存率有显著的相关性．高度大的单芽保存率高，反之则小。造林前的苗高分析表明，单芽苗和丛芽苗第1单芽的保存率与其造林前苗高大于15cm的比率接近，丛芽苗第2单芽的保存率与其造林前苗高大于10cm的比例接近，第3单芽的保存率与其造林前苗高大于5cm的比例接近。与黄藤相同，短叶省藤丛芽苗各单芽的生长速度也与造林前单芽的高度相关，苗高大的单芽生长快，苗高小的单芽生长慢。 相似文献
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Schizostachyum dullooa (Gamble) Majumder ‘dolu bamboo’ is a thin walled sympodial moderate sized to large tufted bamboo, dominant in the successional fallows of northeast India.
The impact of resource management on productivity and sustainability of the species was evaluated by investigating the population
status and regeneration in Cachar tropical semi evergreen forest under private property resource management (PPRM) and common
property resource management (CPRM) regimes. Population status revealed current-year, one-year, two-year and three-year-old
culms contribute 54%, 24%, 16% and 6% of the total culms per clump, respectively, under PPRM. Three-year-old culms were absent
in CPRM and population status was thus represented by current year (83%), one-year (16%) and two-year (1%) old culms. Net
change, rate of change and % gain in population for different age classes showed the prevalence of management practices under
CPRM was unscientific. Efficiency of new culm production per clump used as an index of regeneration was 69.7% in PPRM and
59.88% in CPRM. New culms produced under CPRM were small and thin. We conclude that CPRM is inappropriate for a long term
economic and ecological sustainability of the species and alternative management protocols are needed for conservation of
the species. 相似文献
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为探讨科学而又省力的人工疏花技术,以红富士、新红星为试材,在衡水市旧城、等庄两处果园,研究了苹果一次疏花对坐果及果实发育与品质的影响。结果表明:一次疏花可使红富士的花序坐果率两年平均达7948%,较对照高147倍,新红星平均花序坐果率为7282%,较对照高197倍;且幼果膨大较快,果实平均单果重红富士、新红星分别为26896g、24251g,分别比对照高5009g和3016g,且果个整齐,果形指数提高。 相似文献