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1.
本研究以直根型‘陇东’紫花苜蓿、根蘖型‘甘农2号’杂花苜蓿和根茎型‘清水’紫花苜蓿为试验材料,设置4个刈割强度(距离上次刈割恢复生长分别为20、27、34、41 d),研究不同刈割强度对各根型苜蓿根、茎、叶的贮藏营养物质含量(可溶性糖、蔗糖、淀粉、还原性糖)的影响,为探明不同根型苜蓿刈割后翌年再生状况,为其合理有效利用提供理论依据。结果表明:6月份可溶性糖含量在叶中最高,还原性糖含量在茎中最高,淀粉和蔗糖含量在根中最高,其均值分别为5.75%、2.32%、3.16%、4.38%;9月份可溶性糖、还原性糖、淀粉、蔗糖含量均在根中最高,其均值分别为18.43%、2.57%、5.78%、14.12%。不同根型苜蓿在每27 d刈割强度下可溶性糖、淀粉、蔗糖含量高于其他处理,在每41 d刈割强度下还原性糖含量高于其他处理。根蘖型‘甘农2号’杂花苜蓿和根茎型‘清水’紫花苜蓿秋季根的贮藏营养物质含量接近并高于直根型‘陇东’紫花苜蓿,表明根蘖型、根茎型苜蓿抗寒越冬性较强。 相似文献
2.
旱作条件下紫花苜蓿主要性状对产草量的影响 总被引：2，自引：0，他引：2
研究了31个国内外优良紫花苜蓿品种在旱作条件下8个农艺性状与产草量的关系。结果表明：8个农艺性状与产草量呈显著或极显著的正相关；多元回归分析得出茎粗对产草量的效应最大，其次为叶片数。因此，茎粗、叶片数可作为紫花苜蓿选种、育种、产草量估测和确定刈割适期的两个主要选择指标。 相似文献
3.
生草园捕食性天敌东亚小花蝽的人工操纵技术 总被引：2，自引：0，他引：2
在北京巨山农场果园中，分别在６月初和６月中旬，刈割苹果树行间的紫花苜蓿并将其放在树冠下后，东亚小花蝽既向割草区周围的紫花苜蓿上扩散，也向割草区苹果树上迁移。割草后３天，割草区周围紫花苜蓿上小花蝽数量增加２０％～１１９％，其增加量随距割草区距离的增加而减少，割草区苹果树冠上小花蝽数量比割草前增加２～３倍，蝽螨比可提高１４倍，树冠小花蝽增加的数量受小花蝽扩散能力和割草时间的影响。试验结果表明，适时刈割苹果园中的紫花苜蓿，对控制害螨有明显的作用 相似文献
4.
为确立灌溉农田下紫花苜蓿的刈割制度,2003～2006年在地处西辽河平原的内蒙古民族大学试验农场进行留茬高度效应的研究.结果表明,株高、节间距、根干重、越冬率留茬5 cm刈割均低于留茬10 cm刈割,但1级分枝数、节间数均高于留茬10 cm刈割;营养品质留茬10 cm的好于留茬5 cm的;草产量前2年留茬5 cm较高,而后2年较低,4年总产量留茬10 cm略高;连续4年刈割后田间密度留茬10 cm的较留茬5 cm的高3.8株/m2. 相似文献
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陇东黄土高原春播紫花苜蓿不同茬次生物量动态研究 总被引：2，自引：0，他引：2
尹东 《干旱地区农业研究》2009,27(1):178-183
2003～2005年,在陇东黄土高原区进行的春播紫花苜蓿生物量观测试验表明,春播紫花苜蓿当年的株高,由缓慢增长转为快速增长的转变时段在分枝到现蕾期,由快速增长再次转为缓慢增长的时段在开花期后;生长二、三年紫花苜蓿,一年中适宜刈割三次,前二茬鲜草的平均日增长量明显高于第三茬,并且生长三年的各茬鲜草平均日增长量普遍高于生长二年的;最大地上生物量均出现在第一、二茬,其鲜草和干草重量分别占三茬总重量的76.9%～84.3%和79.1%～86.3%;各茬次紫花苜蓿鲜干比在现蕾期后明显降低,到开花期刈割前降至最低.年际和地域的气候条件差异直接反映在紫花苜蓿各茬次生物量和鲜干比的变化上,在水份满足的情况下,以气温日较差大的地域更有利于紫花苜蓿物质积累. 相似文献
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在内蒙古包头市达茂联合旗哈雅教学牧场 ,采用随机区组法对短花针茅草原在不同刈割时期、次数和高度下的生物量形成规律进行了研究 ,旨在探索短花针茅草原的合理利用方式 ,为草原放牧畜牧业生产实践提供理论依据。研究结果表明 ,短花针茅草原对刈割高度较为敏感 ,适宜的刈割高度为 2 cm;短花针茅草原植物生长缓慢 ,再生能力差 ,不宜于频繁利用 ,一年适宜利用 1 -2次 ;考虑牧草产量和营养物质含量 ,一年两次利用的间隔期应为 2 -3个月 ;一年一次利用的最佳利用期为 8月中旬以后。 相似文献
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2009年至2011年,在陇东黄土高原苜蓿田,分苜蓿返青期、第一茬苜蓿刈割后、第三茬苜蓿刈割后3个时期调查地下害虫的种类、数量及不同深度分布规律。结果表明,该区域苜蓿地下害虫主要有11种,平均密度为18.2头/m2,主要类群按其所占比例大小依次为金龟甲类、金针虫类、网目拟步甲、蝼蛄类和地老虎类,优势种类为黑绒鳃金龟和华北大黑鳃金龟。 相似文献
9.
刈割对伊犁绢蒿根系贮藏营养物质的影响 总被引：4，自引：0，他引：4
以新疆蒿类半灌木荒漠草地建群种伊犁绢蒿为材料,探讨刈割强度对其根系贮藏营养物质的影响.结果表明:不同刈割强度间伊犁绢蒿根中可溶性蛋白、可溶性糖、还原糖含量差异显著(p<0.05),且轻度刈割与中度刈割下可溶性蛋白、可溶性糖、还原糖含量相对较高;不同强度刈割后伊犁绢蒿可溶性蛋白、可溶性糖、还原糖的含量随时间的变化先降低后升高,呈"V"型变化.由于刈割后伊犁绢蒿需要利用贮藏的淀粉维持其再生长,淀粉则呈现下降趋势.而研究结果显示,轻度刈割与中度刈割下淀粉含量相对较高,说明轻度及中度刈割强度下伊犁绢蒿根恢复效果较好,适度刈割有利于伊犁绢蒿可溶性蛋白、可溶性糖、还原糖及淀粉的积累,并可促进其再生长. 相似文献
10.
《杂草科学》2017,(4)
在整个生育期重复使用百草枯或草甘膦,可能引起牛筋草产生抗药性的风险,因此通过盆栽试验比较5种选择性除草剂和2种灭生性除草剂处理及机械刈割处理对牛筋草不同生长阶段的抑制等级及抑制率。结果表明,化学除草效果随着牛筋草生长时间的增加而逐渐下降,选择性除草剂10.8%精喹禾灵乳油0.6 L/hm~2和15%精吡氟禾草灵乳油1.0 L/hm~2对牛筋草的防效与草甘膦基本一致;相同刈割高度时,在牛筋草扬花期之前刈割的防效最高,相同刈割时间时,刈割高度在地上0 cm时对牛筋草的防效最高。本研究明确在牛筋草不同生育时期如何选择最高效的物理或化学防治方法,为牛筋草的综合防治技术提供科学指导。 相似文献
11.
碱化土壤紫花苜蓿不同种植方法与生长关系的研究初探 总被引：4，自引：2，他引：2
土默川地区分布着大面积的碱化土壤和碱土 ,使得该地区农牧业发展受到很大限制。本文研究了不同种植方法 ,不同播期下苜蓿在碱土上的生长状况 ,从而得出了以下结果 :在试验区通过对苜蓿不同种植方式 ,可得出苜蓿以开沟播种覆土盖地膜最佳 ,开沟播种不覆土镇压次之 ,开沟播种覆土镇压产量最低。通过苜蓿不同播期的试验 ,当年以 6月 1 7日播种的产草量最高 ,可得出苜蓿在当年 5月 1 9日次之 ,7月 1日最低。 相似文献
12.
本文研究了内蒙古典型草原地区割草地 ９ 种营养元素的贮量及分配。研究结果表明：刈割对羊草、洽草、其它草种和群落的营养元素贮量产生了一定影响,其贮量有随刈割时间而逐渐增加的趋势。一年内,营养元素的高值期在 ８ 月 ３０日前后。割草区的贮量一般低于对照区,羊草的留茬部分低于割取部分的贮量,洽草则相反。在生物量高峰期 ８ 月 ３０ 日前后,其割草区群落的营养元素贮量为： Ｎ ３． ３５５７ｇ．ｍ － ２, Ｐ ０． １７４７ｇ． ｍ － ２, Ｋ ２．６２０３ｇ． ｍ － ２, Ｃａ １． ０７９５ｇ． ｍ － ２, Ｍ ｇ ０．１２７８ｇ．ｍ － ２, Ｆｅ ０． ０３２４ｇ．ｍ － ２, Ｃｕ １６６９． ６６μｇ． ｍ － ２, Ｍｎ １０３４３． ８４μｇ． ｍ － ２, Ｚｎ３３０３．５１μｇ．ｍ － ２。除 Ｍｎ 外,其它元素都是对照区高于割草区。上述 ９ 种营养元素贮量在割取部分中亦随刈割时间而逐渐增加,高峰期也在 ８ 月 ３０ 日前后,但留茬部分相反。割草区营养元素的贮量多数低于对照区,割取部分多数高于留茬部分。在生物量高峰期 ８ 月 ３０ 日前后,割草区群落的营养元素贮量分配在割取部分的为： Ｎ ６０．８４％ , Ｐ ４９．０６％ , Ｋ ５３．３４％ , Ｃａ ５９ 相似文献
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基于主成分分析的内蒙古草原刈割与放牧退化演替比较研究 总被引：2，自引：0，他引：2
基于多年的野外调查和控制实验数据,采用主成分分析的方法,对内蒙古羊草草原刈割退化演替系列,放牧退化演替系列,退化群落恢复演替系列进行比较研究,研究放牧和刈割影响下群落功能群组成的替变规律。结果表明:PCA排序很好地指示了放牧与刈割演替方向的变化,在功能群的替变上,共同点是根茎禾草减少,不同点是刈割导致小禾草增加,而放牧导致小禾草和小半灌木均增加。PCA排序验证了前人关于8月份刈割对羊草草原群落影响最大的结果。PCA排序显示放牧退化空间梯度系列与退化群落恢复演替时间梯度系列的逆过程一致,表明退化演替研究中时空替代的方法可行。 相似文献
14.
Improved physical control of glyphosate‐resistant Italian ryegrass (Lolium multiflorum) on rice paddy levees in Japan 
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下载免费PDF全文 Valentina Dwi Suci Handayani Yuki Tanno Masayuki Yamashita Hiroyuki Tobina Minoru Ichihara Yoshiki Ishida Hitoshi Sawada 《Weed Biology and Management》2017,17(2):77-83
Italian ryegrass ( Lolium multiflorum Lam.) is a non‐native annual winter grass that has seriously infested rice paddy levees and wheat fields in Japan. Recently, glyphosate‐resistant Italian ryegrass was found on paddy levees in central Japan, thereby making control of the grass by using glyphosate less effective. In this study, physical control methods were tested that combined the timing and frequency of mowing in order to more effectively control glyphosate‐resistant Italian ryegrass on rice paddy levees. A 3 year field experiment was conducted from 2012 to 2014 in a western region of Shizuoka Prefecture, where glyphosate‐resistant Italian ryegrass has become dominant. Five treatments were tested: (i) mowing once before the flowering of the grass (i.e. conventional mowing measure); (ii) mowing once during flowering; (iii) mowing twice during flowering; (iv) glyphosate application before flowering (i.e. one of the conventional mowing measures); and (v) no treatment. The above‐ground biomass, seed production, soil seed bank and seedling occurrence of Italian ryegrass were measured to determine the effectiveness of these treatments. Mowing during the flowering period resulted in reduced above‐ground biomass, seed production and soil seed bank when compared with the other treatments. Additionally, mowing twice during the flowering period resulted in a lower seedling density than mowing once. The results suggest that, in this region, physical control by mowing during the flowering period would be more effective than conventional measures for controlling glyphosate‐resistant Italian ryegrass. 相似文献
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Control of Elymus repens by rhizome fragmentation and repeated mowing in a newly established white clover sward 下载免费PDF全文
下载免费PDF全文 Control of perennial weeds, such as Elymus repens, generally requires herbicides or intensive tillage. Alternative methods, such as mowing and competition from subsidiary crops, provide less efficient control. Fragmenting the rhizomes, with minimal soil disturbance and damage to the main crop, could potentially increase the efficacy and consistency of such control methods. This study's aim was to investigate whether fragmenting the rhizomes and mowing enhance the control of E. repens in a white clover sward. Six field experiments were conducted in 2012 and 2013 in Uppsala, Sweden, and Ås, Norway. The effect of cutting slits in the soil using a flat spade in a 10 × 10 cm or 20 × 20 cm grid and the effect of repeated mowing were investigated. Treatments were performed either during summer in a spring‐sown white clover sward (three experiments) or during autumn, post‐cereal harvest, in an under‐sown white clover sward (three experiments). When performed in autumn, rhizome fragmentation and mowing reduced E. repens shoot biomass, but not rhizome biomass or shoot number. In contrast, when performed in early summer, rhizome fragmentation also reduced the E. repens rhizome biomass by up to 60%, and repeated mowing reduced it by up to 95%. The combination of the two factors appeared to be additive. Seasonal differences in treatment effects may be due to rhizomes having fewer stored resources in spring than in early autumn. We conclude that rhizome fragmentation in a growing white clover sward could reduce the amount of E. repens rhizomes and that repeated mowing is an effective control method, but that great seasonal variation exists. 相似文献
17.
LI Xiliang 《干旱区科学》2016,8(6):899-909
Mowing is an important land management practice for natural semi-arid regions.A growing body of empirical evidence shows that different mowing regimes affect the functioning of grassland ecosystems.However,the responses of plant functional traits to long-term mowing and their allometric scaling under long-term mowing are poorly understood.For a better understanding of the effects of mowing on grassland ecosystems,we analyzed the allometric traits of leaves and stems of Leymus chinensis(Trin.) Tzvel.,a dominant grass species in eastern Eurasian temperate grassland,at different mowing intensities(no clipping,clipping once every two years,once a year and twice a year).Experiments were conducted on plots established over a decade ago in a typical steppe of Xilinhot,Inner Mongolia,China.Results showed that most of the functional traits of L.chinensis decreased with the increased mowing intensity.The responses of leaves and stems to long-term mowing were asymmetric,in which leaf traits were more stable than stem traits.Also significant allometric relationships were found among most of the plant functional traits under the four mowing treatments.Sensitive traits of L.chinensis(e.g.leaf length and stem length) were primary indicators associated with aboveground biomass decline under high mowing intensity.In conclusion,the allometric growth of different functional traits of L.chinensis varies with different long-term mowing practices,which is likely to be a strategy used by the plant to adapt to the mowing disturbances. 相似文献
18.
Daniel Blumberg 《Phytoparasitica》2008,36(5):411-448
This review summarizes the current knowledge on the distribution, natural history, economic importance and management of 16
major species of date palm pests in Israel. Another 15, rarely occurring, pest species are also identified. Research on the
date palm pests in Israel was initiated against a background of severe outbreaks of scale insects in the late 1950s. These
outbreaks were caused mainly by unrestrained use of organophosphates. This situation led to the gradual development of an
Integrated Pest Management (IPM) program, which was implemented first against scale insects and later against fruit pests.
The IMP approach resulted in successful control of the scale insects, up to the present, whereas agrotechnical and crop management
procedures, including covering the fruit bunches with plastic nets and early harvesting of several date cultivars, were successfully
applied to achieve efficient control of the fruit moths. In addition, the use of chemical compounds in date plantations was
drastically reduced and restricted to heavy foci of pest infestation. In time, microbial control, mainly application ofBacillus thuringiensis products against the lesser date moth, and the use of pheromone traps for monitoring and controlling red palm weevil, enabled
further reductions in the use of synthetic insecticides. The overall change in pest management also significantly improved
the preservation of natural enemies of the pests in the plantations. Whereas in the 1950s the major problems were caused by
the parlatoria date scale and the green scale, in the early 2000s the key pests in date plantations in Israel are the lesser
date moth and sap beetles in most of the date-growing areas, and spider mites which are restricted to the Arava Valley. Future
management of the first two of these pests should rely on an improved monitoring system and integration of pheromone application
for reduction of the population and damage. Efforst should be made to prevent the red palm weevil, which currently is a potential
pest, from becoming an actual key pest in date plantations. 相似文献
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XU Bo HUGJILTU Minggagud BAOYIN Taogetao ZHONG Yankai BAO Qinghai ZHOU Yanlin LIU Zhiying 《干旱区科学》2020,12(5):752-765
Effects of mowing on the composition and diversity of grasslands varied with climate change (e.g., precipitation and temperature). However, the interactive effects of long-term mowing and climate change on the diversity and stability of leguminous and non-leguminous species in the semi-arid grasslands are largely unknown. Here, we used in situ monitoring data from 1982 to 2011 to examine the effects of continuous mowing and climate change on the plant biomass and diversity of leguminous and non-leguminous species, and soil total nitrogen in the typical semi-arid grasslands of northern China. Results showed that the biomass and diversity of leguminous species significantly decreased with the increasing in the biomass and diversity of non-leguminous species during the 30-a period. Variations in biomass were mainly affected by the long-term mowing, while variations in diversity were mainly explained by the climate change. Moreover, the normalized change rates of diversity in leguminous species were significantly higher than those in non-leguminous species. Mowing and temperature together contributed to the diversity changes of leguminous species, with mowing accounting for 50.0% and temperature 28.0%. Temporal stability of leguminous species was substantially lower than that of non-leguminous species. Consequently, soil total nitrogen decreased in the 2000s compared with the 1980s. These findings demonstrated that leguminous species were more sensitive to the long-term mowing and climate change than non-leguminous species in the semi-arid grasslands. Thus, reseeding appropriate leguminous plants when mowing in the semi-arid grasslands may be a better strategy to improve nitrogen levels of grassland ecosystems and maintain ecosystem biodiversity. 相似文献