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在果树管理中,修剪是非常重要的环节之一,不同的修剪方式对果树的生长发育、所结果实的品质生产会产生不同的影响.优秀的果品生产要求高光照.冬季对苹果果树的修剪是改善光照环境,调节果树最终结果程度的重要环节.探究了不同冬剪量对苹果越冬幼苗萌芽率及成枝力的影响,结果发现:20％ 及30％ 的修剪量与对照组相比可有效提升苹果幼苗... 相似文献
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果树的环剥和结扎。主要是损伤枝条的韧皮部,阻止叶片光合作用产生的有机养料往根部输送,促使有机养料向花和果实的部位运输;或者提高芽体的细胞液浓度,以利于保果和花芽分化。每年在果树的不同部位轮流环剥4～5根枝条,不妨碍根系的生长,不影响树势,并且能够保证果树连年结果、丰收。但有些果农在果树的主干上进行环剥树皮或用铁丝结扎主干,以促进果树多结果,其实这是违反果树栽培技术的。因为:1.环剥主干树皮,会使主 相似文献
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光照影响果树的生长、发育、产量和品质。光强、光质和光时对果园生态环境产生影响。文章主要揭示了光量、光质和光时对果园的影响,为果树的栽培和管理提供理论依据,提高果树的光能利用率,实现果树的高产量和高质量。 相似文献
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在果树栽培中,果农希望年年结果,高产稳产.可是在生产实践中,常常会遇到一个棘手的问题,即果树的大小年.不同的树种,大小年明显程度也不同.同一树种,不同品种,大小年表现的产量变化幅度也不一样.无疑,大小年的存在,严重影响了果树的经济效益.那么,大小年是怎样产生的?能否预防和克服呢?笔者认为: 相似文献
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林业果树种植技术及果品的质量安全探讨 总被引：3，自引：0，他引：3
指出了随着我国林果业的快速发展,在带来经济效益的同时,生态效益却受到了很大程度的损害,化学农药的泛滥使用,使果品的质量安全问题受到威胁,而果品安全问题主要受林业果树种植技术的影响。主要探讨了我国果品质量安全的现状、产生的原因以及果树种植技术对果品安全的影响,并就此提出了林业果树种植的技术措施。 相似文献
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通过对甘肃各主要林区、保护区的野生果树物种资源调查研究表明:甘肃野生果树资源十分丰富,共有32科、70属、312种和46变种(变型)。甘肃野生果树主要集中在蔷薇科、虎耳草科、小檗科、猕猴桃科、葡萄科、胡颓子科。本文首次对甘肃不同地理区域野生果树资源的丰富度和相似性进行了研究,结果表明甘肃野生果树资源在各地理区域间分布不平衡,陇南、陇东南、陇西南、陇东野生果树资源较丰富,陇中、祁连山区、河西走廊较贫乏。各地区野生果树资源的相似性系数表明,陇南与陇东南野生果树物种资源最为接近,陇南与河西走廊差异最大;提出了甘肃野生果树可持续利用策略。 相似文献
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化学防治是果树病虫害防治的主要技术方式。化学防治技术主要有农药喷雾技术、农药喷撒粉技术、农药灌注堵塞技术、农药涂抹包扎诱杀技术。果树病虫害防治应针对果园病虫害发生的规模、特点、方式,采取不同的防治技术。 相似文献
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不同树体环境和管理水平对苹果树梨树腐烂病发生程度的影响 总被引：3，自引：0，他引：3
苹果树梨树腐烂病是对果树危害严重的一种病害,对果树生产造成了较大的威胁。通过对苹果树梨树腐烂病发生程度的相关性因素的分析,结果表明,苹果树梨树腐烂病的发生程度与果树大小年、树龄、果树生长状况、冻害的发生、土壤管理制度、修剪程度等都有十分密切的相关性:树龄1～10a的发病轻,20a以上的发病重;枝条发育不充实,不能自然落叶的果园发病重,枝条充分成熟的树体发病轻;易遭冻害的果园发病重;清耕不间作的果园发病重,间作的发病轻;重修剪的发病重,轻修剪的发病轻。 相似文献
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毛棉杜鹃 Rhododendron moulmainense 和刺毛杜鹃 R.championae 分布于我国长江以南海拔500～1500 m 的灌丛或疏林,是观赏价值较高的野生观花树木,但极少在城市园林中应用。文章比较研究了毛棉杜鹃和刺毛杜鹃在广州低海拔地区全阳与林下生境的生长表现与物候特点。结果表明：两种杜鹃花属植物在全阳坡地都有较高成活率,能正常开花结果,但夏季生长不良。林下生长的植株表现良好,但未见开花,反映了光照条件是两种植物花芽分化的重要条件。综合比较,毛棉杜鹃在广州的观赏效果和适应性要优于刺毛杜鹃。 相似文献
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Palmer JW 《Tree physiology》1992,11(1):19-33
Fruit load was altered by flower thinning on three- and four-year-old, field-grown apple trees. Increasing fruit load led to increases in dry matter production per unit leaf area and partitioning to fruit and to decreases in fruit size, percentage fruit dry matter, dry matter partitioning to new shoot growth, thickening of existing woody tissue and root growth. Flower bud production for the following spring was also negatively affected by an increase in fruit load. Leaf photosynthesis was increased in cropping trees in July and August at the time of maximum fruit dry weight increase. Calculated light interception was linearly related to leaf area. The efficiency of conversion of intercepted photosynthetic active radiation to dry matter energy equivalents was 3.3% in heavily cropping trees and 1.8% in non-cropping trees. Total dry matter production was linearly related to both leaf area and light interception, but the variance accounted for by the regression was more than doubled if fruit dry matter or fruit number was included in the regression. 相似文献
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Effects of water stress on fruit fresh and dry weights were investigated in peach trees, Prunus persica (L.) Batsch., with varying crop loads: light, moderate and heavy. In well-watered controls, tree water status was independent of crop load. In trees receiving reduced irrigation, the degree of water stress increased with increasing crop load. Water stress induced fruit fresh weight reductions at all crop loads. Fruit dry weight was not reduced by water stress in trees having light to moderate crop loads, indicating that the degree of water stress imposed did not affect the dry weight sink strength of fruit. Water-stressed trees with heavy crop loads had significantly reduced fruit dry weights, which were likely due to carbohydrate source limitations resulting from large crop carbon demands and water stress limitations on photosynthesis. 相似文献
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Louis Kan Koko Didier Snoeck Tacra Thierry Lekadou Assiri Alexis Assiri 《Agroforestry Systems》2013,87(5):1043-1052
A major challenge for cocoa producers in Côte d’Ivoire is to seek alternative shade trees or crop associations to adapt their planting devices and techniques to the shortage of forests. The recent tendency developed by farmers is to plant simplified orchards combining cacao and fruit trees. An on-farm trial was set up in a 5-year-old cocoa farm to compare a cacao monocrop planted at densities of 1,115 trees ha?1 with cacao intercropped with orange or avocado trees, both at 44 trees ha?1. Observations were done on incident light received by the cacao, vigour, growth and cocoa yields. On average, the cacaos received 100 % light in the monocrop, 89.6 % under orange trees and 80.6 % of incident light under avocado trees. They yielded 64.0 pods tree?1 year?1 in the monocrop (equivalent to 2.54 kg dry cocoa beans tree?1), 30.3 pods tree?1 when combined with orange trees and 28.3 pods tree?1 with avocado trees. The two combinations allowed cocoa yields equivalent to those observed in the region (0.58 kg dry cocoa beans tree?1). Vigour and yield were very highly correlated with the incident light received. Both the yield and the incident light are a logistic function of the planting distance from the shade tree. The inflexion point of the logistic functions corresponds to the minimum planting distance between the cacao and the intercropped fruit trees. On this basis, we suggest that the cacaos should not be planted closer than 6.50 ± 0.2 m to the orange or avocado trees. 相似文献
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Tree holdings at homesteads and in homefields were investigated for two villages in Zimbabwe. Of the households, 90% owned
at least one exotic tree. Trees were concentrated at homesteads and conserved indigenous trees tended to be edible fruit trees.
Female heads of households (divorcees and widows) had fewer trees than households headed by men. Households with longer period
of residence at a site had increased the proportion of indigenous fruit trees compared to non-fruit trees. Wealth status showed
no relationship to tree holdings. The considerable tree planting and tree conservation activity around homesteads and in homefields
has the effect of replacing non-fruit indigenous trees with exotic and indigenous fruit trees. Agroforestry research, extension
and development should focus more on current practices, concentrate more on trees that farmers favour (such as fruit trees)
and take into account differences among households.
This revised version was published online in June 2006 with corrections to the Cover Date. 相似文献
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Five-year-old 'Spring' navel (Citrus sinensis (L.) Osbeck) orange trees were completely defruited, 50% defruited or left fully laden to study effects of fruit load on concentrations of nitrogen (N) and carbohydrate, net assimilation of CO2 (Ac) and stomatal conductance (gs) of mature leaves on clear winter days just before fruit harvest. Leaves on defruited trees were larger, had higher starch concentrations and greater leaf dry mass per area (LDMa) than leaves on fruited trees. Both Ac and gs were more than 40% lower in sunlit leaves on defruited trees than in sunlit leaves on trees with fruit. Leaves immediately adjacent to fruit were smaller, had lower leaf nitrogen and carbohydrate concentrations, lower LDMa and lower Ac than leaves on non-fruiting branches of the same trees. Removing half the crop increased individual fruit mass, but reduced fruit color development. Half the trees were shaded with 50% shade cloth for 4 months before harvest to determine the effects of lower leaf temperature (Tl) and leaf-to-air vapor pressure difference on leaf responses. On relatively warm days when sunlit Tl > 25 degrees C, shade increased Ac and gs, but had no effect on the ratio of internal to ambient CO2 (Ci/Ca) concentration in leaves, implying that high mesophyll temperatures in sunlit leaves were more important than gs in limiting Ac. Sunlit leaves were more photoinhibited than shaded leaves on cooler days when Tl < 25 degrees C. Shade decreased total soluble sugar concentrations in leaves, but had no effect on leaf starch concentrations. Shading had no effects on canopy volume, yield or fruit size, but shaded fruit developed better external color than sun-exposed fruit. Overall, the presence of a normal fruit crop resulted in lower foliar carbohydrate concentrations and higher Ac compared with defruited trees, except on warm days when Ac was reduced by high leaf temperatures. 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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插穗粗度对无花果育苗影响的初步研究 总被引：1，自引：0，他引：1
无花果是第三代新兴水果。为了更好地推动其发展,笔者亲自做了插穗粗度对无花果扦插育苗影响的试验研究。试验结果表明,插穗粗度对无花果扦插育苗的成活率、生长状况及商品苗率均有影响。为大量培育无花果苗.提供了可靠的理论依据。 相似文献