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黑龙江省位于我国最北疆,冬季气候寒冷,不刚区域极端最低温度-32~-46℃,年平均温度4.9-1℃,-30℃以下温度持续2~71d,年降水量370~700mm,无霜期110~150d,有效积温1900~2900℃,因受内陆高温气压及两伯利亚季风的交替影响,大陆气候特征明显,具有特定的发展农业的自然优势,发展果树的气候条件虽不如南方省份优越,但昼夜温差大,日照时问长,雨热同季等,适于耐寒果树的生长发育,且果树生产已有多年历史,生产潜力很大,是一个很有开发前途的地区。 相似文献
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指出了杨梅作为亚热带耐寒性常绿果树的核果类,气候是影响最大的外界环境条件,也是保证杨梅优质丰产的基础条件,就浙江余姚地区的气候条件与铜鼓县的气候条件进行对比,从而对余姚杨梅引种铜鼓县的适应性进行分析. 相似文献
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根据龙眼生长发育的主要气候指标,对河口地区影响龙眼生长发育的主要气候因子作回归分析,提出了河口地区龙眼生产气候条件的适宜性区划。区划为最适宜、适宜、次适宜和不适宜区。 相似文献
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甘肃梨开花结实期冻害与防治挽救对策 总被引:1,自引:0,他引:1
梨是甘肃省最主要的栽培果树品种之一,但梨春季开花较早,花期与当地的晚霜期时有相遇,易遭受冻害,轻则减产,重则绝收。为此,研究其冻害成因与防治挽救对策,是目前梨生产中急需解决的问题。一、冻害发生的原因大气候的影响。气候变暖使得终霜日提早,也使梨树开花期提早,抗冻性迅速减弱。但长时间尺度的变暖与短时间尺度的严重低温可以并存,在气候变暖时期完全可能出现几十年不遇的严重霜冻。而梨遇有-1.2℃持续时间在半小时以上的低温,即可遭受霜冻危害。地形地势的影响。甘肃省内地形复杂,洼地、谷地、盆地等 相似文献
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在寒地果树栽培中,冬季常受各种不良环境条件的危害,其中危害最大的是冻害。由于气候严寒低温持续期长,在北方地区几乎每年都发生不同程度的冻害,给生产上造成严重损失。由于果树是多年生作物,不仅影响当年的生长发育,而且还要影响以后多年,常造成树势减弱,腐烂病等病害蔓延,以至死树毁园等现象的发生。为使果树安全越冬,保证果树的品质和产量,采取经济、有效的综合预防措施是非常必要的。 相似文献
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在全球气候变暖的大背景下,我国小兴安岭地区顶级地带性植被阔叶红松林资源逐年锐减,因而其资源保护问题越来越受到关注.通过对小兴安岭红松的年轮与气候进行相关分析发现:1980年前红松径向生长有明显的加速趋势,1980年后红松的径向生长呈较显著下降趋势.温度是小兴安岭红松径向生长的主要限制因子,受月最低温度的影响,红松径向生... 相似文献
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We studied the influence of branch autonomy on the growth of reproductive and vegetative organs by establishing different patterns of fruit distribution within and between large branch units (scaffolds) in mature peach trees (Prunus persica (L.) Batsch cv. 'Elegant Lady'). Different patterns of fruit distribution were established by defruiting either whole scaffolds (uneven fruit distribution between scaffolds; US) or several selected hangers (small fruiting branches) per tree (uneven fruit distribution between hangers; UH). The effects of these patterns were compared with the effects of an even fruit distribution treatment (EVEN) in which fruits were thinned to achieve maximum uniformity of fruit distribution within the canopy. The desired fruit loads were obtained by differentially thinning the remaining bearing parts. On a tree basis, the response of mean fruit mass to fruit load was strongly affected by fruit distribution. The steepest mean fruit mass to fruit load relationship was found in US trees, whereas the relationship in UH trees was intermediate between the US and EVEN trees. On a scaffold basis, differences in fruit size between EVEN and US trees with similar fruit loads, though statistically significant, were relatively small, indicating that scaffolds were almost totally autonomous with respect to dry matter partitioning to fruit during the final stage of peach fruit growth. Hangers also appeared to exhibit significant autonomy with respect to the distribution of dry matter during the final phase of fruit growth. Branch autonomy was evident in scaffold growth: defruited scaffolds in the US treatment grew more than fruited scaffolds, and fruit distribution treatments had little impact on scaffold cross-sectional area on a tree basis. On the other hand, as observed for fruit growth, branch autonomy did not appear to be complete because the fruited scaffolds grew more in US trees than in EVEN trees under heavy cropping conditions. However, the effect of fruit distribution occurred only over short distances, and was negligible on organs located farther away from the source of heterogeneity (fruits), such as the trunk and roots. 相似文献
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通过对枣树施以不同量配比的碳酸氢铵与过磷酸钙的混合肥料以及结合叶面喷施生长素、赤霉素、生长素与赤霉素混合液的方法,研究了不同施肥量和激素处理对枣树的枣吊长、枣股数、枣吊上的枣花数以及座果数的影响。结果表明:适量的施肥处理可提高枣树的开花座果数,其最佳施肥量为氮肥0.8 kg/株,磷肥0.4 kg/株。不同激素处理对枣树的开花座果数有一定的影响,且影响程度各不一样。 相似文献
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论述了落叶果树主要病害的种类、病害化学防治的现状、病害化学防治中出现的问题,并对今后果树病害化学防治进行了展望,以保证果树的高效、高产和优质生产。 相似文献