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徐金良 《农业工程技术:农产品加工》2019,(20)
近年来随着青海省海南州共和县农牧业产业结构不断调整,杏树的种植面积不断增加,经济效益越来越高。为了进一步提高杏树的生产能力,就需要应用嫁接技术对杏树品种进行改良。为了提高嫁接的成活率,可以从接穗采集处理、嫁接时期选择、嫁接方法和嫁接后的处理等各个环节入手,有效提高杏树嫁接的成活率,促进经济效益提升。 相似文献
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瓣胃阻塞主要是由于瓣胃的收缩力减弱或前胃运动机能发生障碍,内容物充满而干稠,不能运到真胃,而引起的阻塞性疾病,笔者在师宗县竹基乡多年的工作中,积累了一些治疗本病的经验,现总结出来和同行交流学习。 相似文献
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杉木无性系改良增产效益的研究 总被引:2,自引:0,他引:2
据对14片试验林102个无性系的调查分析,8年生(含苗龄)以上的82个无性系,平均单株材积比对照(开化1代种子园或那坡优良种源实生苗)增产35.8%,从中筛选出15个优良无性系,平均比对照增产87.1%,其中三个增产1倍以上。试验表明,从杉木优良家系(合优良种源的优良家系)、优良杂交组合和2代种子园的优良种苗营造的幼、中龄林中进行无性系选优,增产效果以优良杂文组合较好,2代种子园次之,1代种子园和优良种源更次之。在增产水平高且后代分化大的优良家系中选择,以选育单系为好;在增产水平高,但后代分化不大的优良家系中选择,以选育多系为好。 相似文献
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本研究测定了浙江省一些林场内杉木林地杉木根际和非根际土壤的微生物数量和酶活性。结果指出,杉木根际和非根际土壤中的微生物以细菌为主,其中氨化细菌占有较大数量。杉木根际土壤的细菌、放线菌和真菌数量都显著地高于非根际土壤。脲酶、蔗糖酶、磷酸酶脱氢酶和纤维素酶活性也有同样趋势,但多酚氧化酶则相反。根际微生物数量和酶活性与土壤化学性质有关。杉木连栽显著地降低根际微生物数量和脱氢酶、纤维酶活性,但增大了多酚氧化酶活性。这表明降低了生物化学活性。而这又会引起根际养分不足和有毒物质积累,导致连栽杉木较低的生长速率。 相似文献
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对无患子果实生长发育动态及果肉内含物含量变化进行研究,结果表明,无患子果实纵径、横径、侧径、鲜质量等性状发育进程呈现明显的S型生长曲线特征;以果实生长发育时期为横轴(x),分别以果实纵径、横径、侧径、鲜质量的均值为纵轴(y),构建的果实生长发育数学模型表明,无患子果实生长各性状与果实发育时期高度相关,数学模型可以正确地反映无患子果实生长发育动态变化规律。对无患子果实脱落规律、果肉含水量、可溶性糖含量、皂苷含量变化规律等综合分析表明,10月下旬,无患子果实发育成熟,生长性状趋于稳定,果肉含水量和可溶性糖含量从峰值下降至相对较低水平,而果肉皂苷含量相对较高,因此提出该时期为无患子果实采摘的适宜时期。 相似文献
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In order to explore the salt tolerance mechanism of Machilus thunbergii, the effects of salt stress on seedling biomass, root morphology, sodium and potassium absorption and distribution were studied. The results showed that the above-ground biomass increased slightly under lower salt stress conditions, while the below-ground biomass, root length and root surface area showed a downtrend. The above-ground growth was limited under high concentration salt stress, while the under-ground growth was not subject to significant restrictions. The absorption of Na+ in root increased under salt stress, but that of K+ decreased. The ability of Na+ transporting from root to leaf and stem was weakened. The accumulation of Na+ in stem and leaves was less. With the decreased absorption of K+, the ratio of Na+/K+ also continuously increased. With the increased concentration of salt stress, the ability of K+ absorption in roots increased. The ability of K+ transporting from root to leaf and stem was enhanced, which resulted in significant increase of K+ in the leaves and stem. The accumulation of Na+ in the under-ground was significantly greater than that in above-ground, while the K+ content in above-ground increased significantly, which played a key role in maintaining normal growth and metabolism of M. thunbergii. 相似文献