设施甜樱桃熊蜂授粉试验

以设施栽培的7年生红灯、莫瑞乌、先锋等甜樱桃品种为试材，进行大棚樱桃熊蜂授粉试验．结果表明。大棚内利用熊蜂授粉较蜜蜂授粉坐果率、单果重均明显提高，果实成熟期也有所提早。认为熊蜂是甜樱桃设施栽培时较理想的授粉昆虫。     

设施大樱桃熊蜂授粉试验

大樱桃设施栽培可以规避自然灾害,使果实提早成熟,大大提高经济效益,但其授粉问题是制约大樱桃产量的关键因素之一。近几年主要是用蜜蜂授粉,也曾有人用壁蜂授粉,但效果很差;人工授粉费工多,掌握不了最佳时间,效果也不尽人意。由于樱桃花量大、花朵密集,蜜蜂体力不够,往往贻误了最佳授粉期,致使坐果率受到很大影响。熊蜂属膜翅目蜜蜂总科熊蜂属,具有旺盛的采集力,对低温、弱光适应力强,有较长的吻,趋光性差、耐湿、信息系统不发达,能专心地在棚内果树上采集花粉,是大棚内较为理想的授粉昆虫。笔者于2004年进行了设施大樱桃熊蜂授粉试验,取得…     

设施果树熊蜂授粉试验

2005年进行了设施果园熊蜂授粉试验。结果表明:设施果树熊蜂授粉比蜜蜂授粉坐果率明显提高,其中油桃高25.5%、金太阳杏高1.02倍、李子高10.81%、大樱桃高66.41%、草莓高13.6%;果实成熟期提前3~5d;油桃、李子、大樱桃、草莓的单果质量分别高3.6、3.0、1.75、6.0g;油桃、李子、大樱桃平均株产分别高2.0、1.5、4.0kg。     

设施果园释放熊蜂授粉试验

设施果树的昆虫授粉，目前多数用蜜蜂授粉，但其活动温度较高，相对缩短了其有效授粉时间，致使达不到理想的坐果率。为此，山东省淄博京鲁生物授粉有限公司筛选了一种专为设施作物授粉的蜂种熊蜂，并进行工厂化生产取得成功。它活动温度低，飞翔能力强，访花次数多，专以花粉为食，不采蜜。为了验证熊蜂在设施果树上的授粉效果，我们在2004年舂小规模试验取得成功的基础上（试验结果已刊登在《北方果树》2004年第6期上），于2005年春进行了大规模对比试验，现将2005年试验结果报告如下。     

设施果园释放熊蜂授粉试验

设施果树的昆虫授粉,目前多数用蜜蜂授粉,但其活动温度较高,相对缩短了其有效授粉时间,致使达不到理想的坐果率.为此,山东省淄博京鲁生物授粉有限公司筛选了一种专为设施作物授粉的蜂种--熊蜂,并进行工厂化生产取得成功.它活动温度低,飞翔能力强,访花次数多,专以花粉为食,不采蜜.为了验证熊蜂在设施果树上的授粉效果,我们在2004年春小规模试验取得成功的基础上(试验结果已刊登在<北方果树>2004年第6期上),于2005年春进行了大规模对比试验,现将2005年试验结果报告如下.     

设施樱桃园熊蜂授粉试验

大樱桃设施栽培,提早成熟,可以大大提高其经济效益,但其授粉问题也成为突出问题.近几年,生产中主要是用蜜蜂授粉.也曾有人用过壁蜂授粉,效果很差.由于樱桃花量大,花朵密集,蜜蜂体力不够,往往贻误了最佳授粉期,致使坐果率受到很大影响.针对这一问题,我们在淄博京鲁生物授粉有限公司的大力支持下,于2004年进行了设施内大樱桃熊蜂授粉试验,取得了较好的效果.现将试验结果报告如下.     

设施番茄熊蜂授粉试验

在试验区实施熊蜂授粉技术,通过与激素授粉相比较,以期探明熊蜂授粉对番茄产量、品质的影响.试验结果表明,与激素授粉相比,熊蜂授粉番茄产量显著提高、番茄籽粒数增加、畸形果率显著降低、VC含量提高、可溶性固形物含量变化不大、糖酸比(可溶性糖与可滴定酸比值)降低.     

设施农业熊蜂授粉技术研究进展

熊蜂是设施农业最理想的授粉昆虫之一.本文对熊蜂蜂群组成及生物学特性,熊蜂授粉的优势、技术要点及其在设施农业中的应用效果进行了总结阐述,以期促进熊蜂授粉技术的推广应用,为设施农业带来更好的经济效益和生态效益.     

大棚樱桃熊蜂授粉试验

大樱桃设施栽培可以规避自然灾害,使果实提早成熟,大大提高经济效益,但其授粉问题也是当前制约大樱桃产量的关键因素之一.近几年,主要是用蜜蜂授粉,也曾有人用过壁蜂授粉,但效果很差;人工授粉费工多,掌握不了最佳时间,有一定作用,但也不尽如人意.由于樱桃花量大,花朵密集,蜜蜂体力不够,往往贻误了最佳授粉期,致使坐果率受到很大影响.针对这一问题,我们在淄博京鲁生物授粉有限公司的大力支持下,于2004年进行了大棚樱桃熊蜂授粉试验,主要研究大棚内利用熊蜂授粉和蜜蜂授粉的不同,找出设施条件下大樱桃较理想的传粉昆虫,提高大樱桃的产量和品质,增加经济效益.     

设施栽培桃树主干形整枝技术

主干形是桃设施栽培中较理想的树形。选70~90cm、基径1.0~1.8的壮苗定植,株行距1.2~1.5m×1.5~2.0m。春季新梢30cm时,将顶端健壮新梢绑立柱上,培养中心干,下部选3个新梢培养主枝。第二层主枝2个,与第一层主枝间距60~80cm,且宜选在树冠北部。向上隔25~35cm再留1~3个小主枝或枝组。生长季依据树形、群体结构随时对方位、角度不当枝进行调整,当年完成整形。第一年骨干枝轻剪长放。坐果后对无果枝、直立旺枝缩剪疏除。采后控长,调整树形,维持树冠大小。     

Stimulating productivity of hydroponic lettuce in controlled environments with triacontanol

Triacontanol (1-triacontanol) applied as a foliar spray at 10(-7) M to 4-day-old, hydroponically grown leaf lettuce (Lactuca sativa L.) seedlings in a controlled environment increased leaf fresh and dry weight 13% to 20% and root fresh and dry weight 13% to 24% 6 days after application, relative to plants sprayed with water. When applied at 8 as well as 4 days after seeding, triacontanol increased plant fresh and dry weight, leaf area, and mean relative growth rate 12% to 37%. There was no benefit of repeating application of triacontanol in terms of leaf dry weight gain.     

The effects of trees on air pollutant levels in peri-urban near-road environments

It is often stated that plants remove air pollutants from the urban atmosphere with their large leaf area, thus providing benefits − i.e. ecosystem services − for citizens. However, empirical evidence showing that local-scale air quality is uniformly improved by urban forests is scarce. We studied the influence of conifer-dominated peri-urban forests on the springtime levels of NO₂ and particle pollution at different distances from roads, using passive samplers and high time resolution particle counters in a northern climate in Finland. Passive samplers provided average values over a one month period, while active particle counters provided real time measurements of air pollution to mimic human inhalation frequency. NO₂ concentrations were slightly higher in forests than in adjacent open areas, while passive particle measurements showed the opposite trend. Active particle monitoring campaigns showed no systematic forest effect for PM2.5, but larger particles were reduced in the forest, corroborating the passive sampling result.Attenuation rates of the mean values of the studied pollutants did not differ between the forest and open habitats. However, high time resolution particle data revealed a distance effect that was apparent only in the forest transect: peak events at the forest edge were higher, while peaks furthest from the road were lower compared to the open transect. Furthermore, the magnitude of PM2.5 peak events was distinctly higher at forest edge than equivalent distance in the open area.Vegetation characteristics, such as canopy cover and tree density, did not explain differences in pollutant levels in majority of cases. Our results imply that evergreen-dominated forests near roads can slightly worsen local air quality regarding NO₂ and PM2.5 in northern climates, but that coarser particle pollution can be reduced by such forest vegetation. It seems that the potential of roadside vegetation to mitigate air pollution is largely determined by the vegetation effects on airflow.     

Effects of water deficit on olive trees cv. Chemlali under field conditions in arid region in Tunisia

Water scarcity in the Mediterranean basin in addition to the extension of irrigated lands is one of the main factors limiting agricultural development. The need for supplementary irrigation of the Chemlali olive cultivar (Olea europaea L.) during summer and autumn periods was investigated. Leaf water content, gas exchange parameters, fruit development and yield in rain-fed and in irrigated plants have been monitored in 12-year-old olive trees grown under environmental conditions in semi arid regions characterized by high temperatures and high light intensity. Trees were subjected to three irrigation treatments, T0, T1 and T2 corresponding respectively to 0, 33 and 66% of crop evapotranspiration (ET_c) by a drip irrigation system. The water deficit during the summer (from June to August) led to the decrease of soil moisture, leaf water content and gas exchange parameters. Irrigated trees showed the same slow activity in the three summer months as the rain-fed trees. For all treatments, net CO₂ assimilation, stomatal conductance and transpiration rates were markedly decreased by environmental conditions (high air temperature and high light intensity) during the summer period. At the partial active growth phase of the Chemlali olive cultivar (September–November), a significant re-increase in all parameters was observed. However, net photosynthesis and stomatal conductance of control plants (T0) were, respectively, 57 and 40% lower than those of plants conducted under milder water contribution (T1). The decrease of physiological activity in irrigated plants during hot and dry (summer time) and cold (winter) seasons was a clear evidence that water supply during such periods will be without a great benefit for photosynthetic activity, and thus growth, if applied under critical conditions inducing the rest phase of the plant. The non-statistically significant slight differences as well in photosynthetic performances activities (Pn, Gs and E rates), as in olive production between the two irrigated treatments will not cover the expenses of water loss when applying irrigation at 66% of ET_c especially in arid region characterized by scant and irregular rainfall. On the light of these results, we can conclude that the irrigation of this species during the vegetative growth phase (in spring and autumn), and stopping it during the olive rest phase (in summer and winter) could be recommended at least under the experimental conditions of this study; and that the contribution of 600 mm of water per year (33% of ET_c) can respond to the needs of the Chemlali olive cultivar in a semi arid region without impairing photosynthetic activity and olive production.     

Flowering and bolting in carrot. II. Prediction in growth room,glasshouse and field environments

Rates of bolting and flowering in carrots cv. Chantenay Red Cored, measured as the reciprocals of days to first internode visibility and flower bud appearance respectively, were shown to relate linearly to a thermal time of vernalization derived from data obtained in controlled environments. Days elapsed from the end of vernalization to the start of visible bolting and flowering bore a curved relationship to thermal time of vernalization. The model curves also predicted closely the bolting and flowering responses of carrots to vernalization at different temperatures in controlled environments and under markedly different conditions in the field. Time taken from the end of vernalization to flowering and bolting decreased with increasing thermal time of vernalization, particularly between ca. 110 and 400°Cd. Vernalization beyond 400°Cd had less effect on the timing of these processes. The percentage of plants flowering increased asymptotically with increasing thermal time of vernalization up to ca. 400°Cd whereas shoot extension increased linearly up to ca. 650°Cd.     

黄土高原苹果树各生育期需水特征研究

【目的】准确界定苹果树在各个生育期的需水量及需水特征的季节性变化是指导果园节水灌溉的重要依据。【方法】利用热扩散树干液流测定技术,连续2年监测了旱作果园苹果树(盛果期)的树干液流速率,计算了单株的耗水强度,并与同步观测的叶面积指数、物候特征进行关联分析。【结果】2017、2018年苹果树年耗水量分别为295.5 mm、215.3 mm,分别占同期降水量的88%和58%。在整个年生育周期中,果实膨大期耗水量最多,占果树整个生育期耗水总量的51%(2017年)和41%(2018年),其次依次为果实成熟期、幼果形成期、花期、萌芽期、落叶期和休眠期,不同生育期果树的耗水量与同期降水量具有相似的季节变化趋势。在萌芽期,果树耗水强度快速上升,到果实膨大期时最高可达2.17 mm·d^-1;之后逐渐下降,在落叶期时耗水强度最高值为1.19 mm·d^-1;休眠期树液仍有流动,此阶段的耗水量占年蒸腾总量的5%,日蒸腾强度最高为0.53 mm·d^-1。冠层叶面积指数(LAI)的季节变化表现为从4月初展叶开始快速增加,到5月上旬达到3.2,日增速平均为0.07;之后LAI基本维持不变,日增速仅为前期的1%,最高值为3.4。在11月中旬左右遇到大风天气后快速落叶,LAI在数天内降至零。【结论】苹果树在不同生育期的需水特征有明显的差异,且与叶面积指数的季节变化并不完全同步,需结合不同生育期的水分需求特征开展合理的灌溉、控水等管理措施。     

南蛇藤果实提取液对弧菌的体外抑菌作用

用平板牛津杯法和试管二倍稀释法比较南蛇藤乙酸乙酯相、水相、乙醇相3种提取液对弧菌的抑菌活性和最小抑菌浓度(MIC)。探讨南蛇藤果实提取液对鳗弧菌、副溶血弧菌的体外抑菌作用。结果表明:3种提取液的MIC值分别是145.8、208.32、91.7 mg/mL(鳗弧菌);125.01、87.52、08.33 mg/mL(副溶血弧菌)。南蛇藤果实的3种提取液对鳗弧菌、副溶血弧菌有不同程度的抑制作用,其中乙酸乙酯相提取液抑菌效果最佳,水相和乙醇相次之。     

Apparent nitrogen mineralization and recovery of nitrogen supply in field trials with vegetable crops

Summary

A major cause of uncertainty in predicting the demand of nitrogen (N) fertilizer by means of mathematical models is the treatment of apparent net N mineralization (ANM) and apparent recovery rate (REC) of mineral N supply (N fertilizer plus soil mineral N at planting). REC and ANM were analysed in 29 multi-level N fertilizer trials conducted with a range of vegetable crops over a period of 11 years. REC differed substantially between experiments (0.29 to 1.24). ANM ranged from 13;110 to 140 kg N ha^–1; it decreased with an increasing N supply, and increased with the time between planting and harvest. A simple regression model was used to predict ANM. The model consisted of both a N supply-dependent and supply-independent term, and used N supply and growing time as input parameters. Whereas the model significantly reduced the variance in measured ANM (r² = 0.45, n = 129), the residuals showed a considerable variation (standard deviation (SD) = 37 kg N ha^–1). It is not feasible to predict N fertilizer demand without predicting net N mineralization and fertilizer recovery. Therefore, the regression model is recommended despite its inaccuracy, which is taken into account by adding a security margin to the fertilizer recommendation.     

中国鸡(土从)菌研究进展

鸡(土从)菌(Termitomyces spp.)是我国传统的典型野生食用菌,具有极高的科学研究价值。由于鸡(土从)菌无法人工栽培,年产量波动严重,市场价值较高,这导致了以假乱真的现象屡见不鲜,并造成了我国鸡(土从)菌市场和科研领域的混乱。通过综述鸡(土从)菌的分类地位、生物学特性、与白蚁的共生关系、食(药)用价值以及鸡地从菌栽培现状等,分析和展望了未来可能的研究方向。为推动鸡(土从)菌人工栽培研究以及传播正确的鸡(土从)菌知识提供参考,从而促进整个鸡(土从)菌产业的可持续发展。     

常用农药对拮抗木霉菌的生长抑制作用

选用24种常用农药配成一定浓度的含药PDA培养基,以不加农药的PDA培养基为对照,接种木霉菌株菌饼,测定木霉菌株的生长速率,计算农药对木霉菌株的生长抑制率,并以此为依据通过SPSS聚类分析对农药进行分类,研究24种常用农药对拮抗木霉菌株生长的影响。研究结果表明,不同类型农药对木霉菌的生长抑制作用存在一定差异,抑制作用大小依次为杀菌剂除草剂杀虫剂,作用最强的为多菌灵、多抗霉素、甲基硫菌灵,其对4个木霉菌株生长抑制率均为100%;作用最弱的是霜霉威盐酸盐,对4个菌株的平均抑制率为-4.06%,表现出一定的促进作用。聚类分析结果显示,当距离值为5.45时,24种农药可划分为4类。