The nutrient levels in fruiting and non-fruiting terminals of three mango cultivars

The leaf nutrient status of 3 mango cultivars, determined in fruiting and non-fruiting terminals after fruit harvest (June 1976) from 20 orchards, were compared. N, P and Ca contents were significantly higher in ‘Dashehari’ than in ‘Chausa’ and ‘Lucknow Safeda’. The reverse was true for K, S and Zn contents. Mg and Mn contents were more or less at par in all the 3 cultivars. Leaves collected from non-fruiting terminals contained significantly higher amounts of N and P in all the 3 cultivars, but K, Ca, S and Zn only in 2 cultivars, as compared to those from fruiting terminals. Mn and Fe contents in both kinds of terminals were more or less at par in all the 3 cultivars.     

攀西杧果园土壤pH值与有效养分的相关性研究

采集攀西杧果主产区果园土壤样本42份,探讨土壤pH值、有效养分状况及两者的相关性。结果表明,攀西杧果园土壤pH值范围为4.8~8.4,中性、酸性土壤占76.2%。果园土壤有机质、碱解氮、交换性钙和有效锌表现为严重缺乏状态,有效铜和硼整体处于低水平,有效钾含量为中下水平,而有效磷、交换性镁、有效硫、有效铁和有效锰5种元素的含量较为丰富。土壤pH值与有机质、碱解氮、有效钾、有效铜、有效锌、有效铁、有效锰呈极显著负相关,与交换性钙、有效硫呈极显著正相关,与有效性磷、有效硼、有效钼的相关性不显著。土壤pH值与有机质符合幂函数,与碱解氮、有效锌、有效硫呈线性相关,与有效钾、交换性钙、有效铜、有效铁、有效锰则符合指数函数,与交换性镁则符合二次函数,各相关系数均达极显著水平。     

The yield gap of mango in Phrao,Thailand, as investigated through comparative performance evaluation

Farmers in Phrao, north Thailand, have often, on a “trial-and-error” basis, planted mango (Mangifera indica L.) in orchards composed of mango, lychee (Litchi chinensis Sonn.) and longan (Dimocarpus longan Loureiro). This met with varying success. In 1993, a comparative performance analysis (CPA) of 45 orchards containing mango was done to identify land and management aspects that condition the level of the mango productivity. The orchards were often situated on podzolic soils on hills, footslopes, and terraces that dry out deeply during the dry season. Yields were expressed in farm-gate prices since middlemen purchased the produce from farmers “on the tree”. With many orchards having “low” yields and 18 having “0” yield, the yield data had a loglinear distribution. Using data from all sites, a final model that estimates Ln(yield+1) was derived; it quantifies contributions to the total yield gap for each identified specific yield constraint. It suggests that yields increased if: (i) it was not an “off” year (caused by the biennial bearing behaviour of mango; use of growth regulators may remedy this); (ii) the orchard was situated on a hill or on soils with a relatively high pH or poor water holding capacity (mostly shallow soils with SCL topsoil; water stress causes crop dormancy and induces flower initiation); (iii) the possibility existed to apply supplemental irrigation water (orchards having a growth flush or in a fruit bearing stage require adequate water management possibly including supplemental irrigation); (iv) in established orchards weeding by tractor was practised (this causes root pruning that affects the trees physiological cycle); (v) pruning was practised (this was normally done to remove branches damaged by stem boring caterpillars, all orchards suffered from this serious problem); (vi) spraying by motor sprayer was done that dispenses pesticides, preferably Azodrin (monocrotophos), deep into the canopy. Based on data covering one production season only, the model suggests that environmental factors (location and pH) account for some 30% of the yield gap defined by the difference of the average production situation with the anticipated best one, that management factors account for 49% and the year effect (species attribute) for 21%. Management of mango orchards requires use of up-to-date technology since responses provide exponential returns. It not only demands that farmers are knowledgeable and experienced but also that a well-informed extension service collaborates closely with researchers.     

Acreage and production estimation of mango orchards using Indian Remote Sensing (IRS) satellite data

In order to exploit the potential of remote sensing in the field of horticulture, a study was initiated to estimate acreage and production of mango orchards using Indian Remote Sensing (IRS) satellite data. The data from linear imaging self scanning (LISS) II of IRS 1B and IRS 1C LISS III data covering the study area have been used. The boundary mask as well as sample segment approaches were tried for acreage estimation. Available yield data and meteorological and growth parameter data were collected to develop an agro-meteorological model. The study has clearly demonstrated the usefulness of LISS II and LISS III data for identifying and estimating mango orchard acreage. It was observed that use of LISS III is better compared to LISS II as the spatial resolution has improved the classification using maximum likelihood algorithm. The study also indicated that the condition of orchards could also be assessed to some extent. Total enumeration technique using summer season data gave very accurate acreage estimates of mango. The sampling approach is also good for mango orchard acreage estimation which provided almost the same accuracy as total enumeration technique but by saving about 6–8 times the analysis time and cost. Due to non-availability of reliable data at different levels, it was difficult to develop any regional level single yield model. However, it was observed that an agro-meteorological data-based model could be developed by collecting such data for 3–4 years in selected orchards.     

Standardization of leaf-sampling technique for mineral composition of leaves of mango cultivar ‘Chausa’

The effects of leaf age, leaf position on the shoot, sampling-direction and sampling-height of leaves of mango cultivar ‘Chausa’ on their mineral composition were studied. The P and K contents decreased, while Ca, Mg, S and Mn contents increased significantly with advancing age of leaves. In general, N, P, Mg, S, Zn, Mn and Fe contents were stable in 6- to 7-months-old leaves. P, K, Ca, Mn and Fe contents varied with sampling-direction, while K, Ca, S, Zn, Cu and Fe contents were significantly higher in the leaves from the lower portion than from the upper portion of the tree. A continuous increase in Ca and Mg contents and decrease in K and Mn contents of leaves were observed from basal to terminal leaves on a shoot. It was concluded that 6- to 7-months-old leaves from the middle of non-fruiting shoots, sampled from all directions and heights, were most suitable for assessing the nutritional status of a mango tree.     

赣南不同土壤类型脐橙园叶片营养状况研究

从赣州市10个县(市、区)的沙质红壤、黏性红壤、紫色土和黄壤等131个枳砧纽荷尔脐橙园采样测定叶片营养元素含量,分析营养丰缺状况。结果显示,赣南脐橙园普遍存在叶片氮、钾偏高而镁、锌不足的问题。土壤类型对叶片氮、磷、钾、钙、镁、铁和锰含量有显著(P<0.05)影响:沙质红壤果园磷、铁更为丰富;黏性红壤果园氮含量最高,钾的过量程度和镁的缺乏程度都最轻;黄壤果园磷更丰富,钙更缺乏,锰最容易过量;紫色土果园氮、磷含量最低,钾易过量,钙较丰富,镁最缺乏,有部分pH值较高的果园植株缺铁。叶片硫、锌、铜、硼和钼在不同土壤类型的果园间差异不显著(P>0.05),但有相当比例的脐橙园叶片缺铜,少量果园叶片缺硼,大多数果园叶片硫含量适宜,所有果园叶片钼含量适宜。     

三峡库区部分柑桔园土壤营养状况的初步研究

研究了三峡库区忠县、丰都县和北碚区3个县(区)27个柑桔园10～35 cm土层4种土壤类型的营养状况并对其作了初步分析.结果表明,3个地区柑桔园土壤pH值多数适宜柑桔生长,土壤有机质含量普遍处于低水平;多数果园土壤大量元素的有效含量处于缺乏范围;中量元素有效Ca和Mg含量较为丰富,S含量较低;微量元素的有效含量多数处于适宜范围,但碱性紫色土有效Fe和Zn含量较少;土壤pH值与有机质含量对土壤其他有效营养元素含量影响显著.综合评价三峡库区柑桔园4种土壤类型的肥力水平依次为:水稻土>酸性紫色土>黄壤土>碱性紫色土.造成这种差异的原因与成土母质及土壤受侵蚀程度不同有很大关系.     

The effect of fruiting status on nutrient composition of litchi (Litchi chinensis Sonn.) during the flowering and fruiting season

Summary

The pattern of leaf composition was investigated in three litchi orchards (cvs Bengal and Tai So) in subtropical Australia (Lat 27°S). Leaves were sampled from fruiting and non-fruiting branches from flowering to fruit harvest. The response to fruiting varied with the nutrient and the orchard. The major effect of fruiting was to reduce leaf K in two of the orchards. Leaf N, P, Zn and Na were lower in fruiting branches in a third of the orchards, while leaf Ca, Mg, Mn and B levels were higher. The levels of these nutrients in the other two orchards, and those of Cu and Fe, were not significantly affected by fruiting status. Strong seasonal effects from flowering to harvest on the leaf contents of most nutrients followed the typical pattern as leaves aged. Most nutrients were more stable during flowering to just after fruit set. The levels of most nutrients were similar in both leaf and fruit. The major exceptions were K which was about twice as high in the fruit and B which was five times higher in the leaves. The uptake of all nutrients continued throughout fruit growth in proportion to the accumulation of fruit dry weight and reached a maximum rate during the final period of aril (flesh) development. The relative order for final content in the fruit was: K>N>P>Mg>Ca>Na>Fe>Zn>Cu>Mn>B. The choice of branch type and time of sampling would influence the diagnosis for N, K, Ca, Mg and Fe at these sites. It is recommended that leaves for diagnostic purposes in litchi be collected from fruiting branches two to six weeks after fruit set.     

Usage of Shoot Analyses to Assess Early-Season Nutritional Status of Apple Trees

Mid-summer leaf analyses are commonly used as the standard method worldwide to assess the nutritional status of fruit trees. However, the analyses performed at this period yield information only about current nutritional status of the trees. Several physiological processes influencing yield and quality take place early in spring. It was reported in previous studies that dormant-season shoot analyses for some nutrients may reliably be used to assess early-season nutritional status of peach trees.The present study was conducted with the shoot samples taken in dormant-season of 150 apple orchards from Isparta region during the years 2010 and 2011. Shoot samples were taken 15 days before full bloom stage and samples were subjected to nutrient analyses. Reference values for each nutrient were indicated as 25 and 75% of the resultant values. The shoot reference values for N, P, K, Ca, Mg, Fe, Mn, Zn and B were respectively observed as 0.66–0.82%, 0.12–0.15%, 0.37–0.45%, 0.84–1.24%, 0.11–0.16%, 24.55–32.24?ppm, 11.12–17.55?ppm, 12.96–21.90?ppm and 13.33–16.00?ppm. To check the reliability of shoot analyses, leaf samples were taken from the same orchards in 7 different periods until mid-vegetation season and correlations between nutrient contents of shoots and nutrient contents of leaves taken in all periods were investigated. Significant correlations were observed between N, P, K, Mg, Mn and B contents of shoots and leaves. Therefore, it was concluded that early-season shoot N, P, K, Mg, Mn and B analyses could reliably be used to assess nutritional status of apple trees.     

兰州苹果园叶螨优势种演变原因其防治对策初探

通过对不同化学防治水平苹果园叶螨种群数量的调查、室内杀虫(螨)剂对叶螨相对毒性的测定以及对叶螨在苹果叶片上的分布及为害性状的考察表明:①频繁施用杀虫(螨)剂的果园.苹果全爪螨的种群数量明显大于李始叶螨种群数量;施用杀虫(螨)剂次数少的果园,李始叶螨的相对数量均高于苹果全爪螨;多年不喷洒杀虫(螨)剂的果园.李始叶螨种群数量占绝对的代势.②苹果全爪螨对三氯杀螨醇的扰性显著强于李始叶螨.③李始叶螨和苹果全爪螨在苹果叶片上存在着相互干扰.营养竞争等现象.进而证实田间大量使用三氯杀螨醇是促使兰州苹果园叶螨优势种演变的主要原因.并对压低苹果全爪螨发生基数和控制苹果园叶螨的防治对策进行探讨.     

杧果果实潜伏侵染真菌种类研究

为了探明杧果果实真菌的潜伏侵染状况,采用组织分离法对采自华南6省区的杧果果实真菌潜伏侵染进行研究,结果表明,我国杧果果实普遍存在真菌的潜伏侵染现象,但不同省区的带菌率存在显著差异,果柄和果实蒂部的带菌率极显著高于果实中部和端部的带菌率。共鉴定11种潜伏侵染真菌,分别为胶孢炭疽菌(Colletotrichumgloeosporioides Penz.)、可可球二孢菌(Botryodiplodia theobromae Pat.)、尖孢炭疽菌(Colletotrichum acutatum Sim-monds.)、杧果拟茎点霉(Phomopsis mangiferae Ahmad.)、杧果拟盘多毛孢(Pestalotiopsis mangiferae(P.Henn.)Sutton.)、多米尼加小穴壳(Dothiorella dominicana Pet.et Cif.)、杧果大茎点霉(Macrophoma mangiferae Hing.&O.P.Sharma)、链格孢(Alternaria alternata(Fr.)Keissl.)、曲霉(Aspergillus sp.)、弯孢霉(Curvularia sp.)、镰刀菌(Fusarrium spp.)。其中,胶孢炭疽菌(C.gloeosporioides)、可可球二孢菌(B.theobromae)为主要潜伏侵染真菌,杧果大茎点霉(M.mangiferae)为首次报道的杧果潜伏侵染真菌。     

东北地区黑穗醋栗营养状态研究

东北地区黑穗醋普遍存在着潜在缺Ｋ和元素间平衡关系失调的问题。叶片中Ｋ素含量偏低，而Ｐ和Ｍｇ含量偏高；叶片中Ｎ含量在一部分果园偏高，而另一部分果园偏低，叶片中微量元素含量基本处于正常范围。施肥与否和不同产量条件对叶片中元素含量有明显的影响。改变玑行的重视Ｎ肥是改善黑穗栗营养状况的有效途径。     

福建柑桔园营养施肥状况及其施肥改进建议

以福建省永春等10县（市）70片（≥3．5hm2）柑桔示范园为代表,通过土壤、叶片分析及施肥状况的综合诊断得出的结果表明：84％的示范园土壤显著酸化（pH＜5．5）,主要是施用N、P、K化肥造成的;营养失调也普遍存在于示范围中,其中主要元素缺Ca、P吸收障碍及微量元素B、Cu的过量尤为普遍;施肥中有机肥不足,P、N肥滥用,Ca、Mg、K肥欠缺;叶片K、Mg并不简单受其土壤有效成分的影响,叶片K与土壤"全N／有效K"、"水解N／有效K",叶片Mg与土壤"代换Mg／代换Ca"呈极显著相关（P＜0．01,r=-0．36、-0．39、0．49）。据此,对以红壤为主要土壤类型的福建柑桔产区的施肥提出了改进建议。     

Effect of wool-lined plastic caps impregnated with Bacillus licheniformis or copper oxychloride and sun-protector to prevent sunburn and control diseases in mango fruit

Summary

An innovative new strategy to apply copper fungicides, or the bacterial antagonist Bacillus licheniformis, to plastic caps with an added inner wool lining to protect mango fruit against both sunburn and disease was evaluated. Sun-protector sprayed onto trees alone, or as a carrier for the bacterial antagonist was also evaluated. Both capping and spraying treatments were evaluated over two growing seasons on two farms representative of different production regions in South Africa. Attachment and survival of the antagonist on the wool-lined caps were evaluated over 3 months using scanning electron microscopy. The use of wool-lined caps on mango fruit in the orchard led to a significant reduction in sunburn damage and provided an effective niche for B. licheniformis to attach and survive. However, wool-lined caps impregnated with copper fungicide or the bacterial antagonist had little added effect in controlling disease under field conditions when the disease pressure was low. Sun-protector, although intended to shield fruit from sunlight, proved ineffective against sunburn and did not further improve disease control when used as a carrier for biocontrol products. However, wool-lined caps alone have the potential to protect fruit against sunburn and infection over extended periods when farmers cannot gain access to their orchards.     

三峡重庆库区甜橙叶片矿质营养丰缺状况调查

 为了解三峡重庆库区甜橙叶片矿质营养丰缺状况,2009年对库区5个甜橙主产县200个甜橙园4 ~ 6月龄营养性春梢叶片营养元素进行了分析测试。结果表明,三峡重庆库区甜橙叶片营养明显失衡,N和Fe含量很高,P、Zn和Mo比较适宜,K、Ca、Mg、Cu和Mn含量较低,而B含量严重不足。叶片N、P、K、Ca和Mg的平均含量分别为（27.34 ± 5.92）、（1.40 ± 0.21）、（11.00 ± 3.04）、（25.27 ± 8.53）和（3.34 ± 0.89）g · kg^-1,Fe、Cu、Mn、Zn、B和Mo的平均含量分别为（125.00 ± 40.55）、（5.38 ± 2.59）、（33.69 ± 6.33）、（34.30 ± 17.91）、（23.68 ± 14.24）和（0.79 ± 0.49）mg · kg^-1,且N和Fe处于高量及以上水平的比例分别为39.5%和53.0%,P、Zn和Mo在适宜范围的比例分别为75.5%、83.5%和70.5%,K、Mn和Mg处于低量水平的比例分别为50.3%、37.5%和20.0%,B、Ca、K、Cu在低量及以下水平的比例分别为76.5%、64.0%、57.3%和51.0%。库区大部分橘园叶片B含量严重不足,生产上需要重视补充B肥;同时生产上需根据甜橙叶片营养诊断结果,适量补充Ca肥和K肥,以满足柑橘营养平衡施肥。     

环渤海湾地区主要梨园树体矿质营养元素状况研究

 以叶片矿质营养元素含量作为树体营养诊断的依据,对环渤海湾地区有代表性的203个梨园树体矿质营养状况及相应土壤养分状况进行了研究,结果表明：（1）该地区81% ~ 97%的梨园叶片P、Ca、Mg、Fe含量处于适宜状态,26% ~ 40%的梨园叶片N、K、Zn含量偏低。（2）除Mg、Zn外,不同梨树品种间叶片中矿质营养含量差异明显。与其它品种相比,苹果梨N、P含量较高,而K含量偏低;莱阳茌梨N含量较低,而P、K含量较高;砀山酥梨N、P、K含量均偏低。（3）初步筛选出N/P、Mg/P、Zn/P、K/Mg、Ca/Mg、Zn/Mg作为该地区梨园营养诊断与施肥建议综合法的营养诊断参数,低产梨园各元素需肥顺序大致为Mg > P > Ca > K > Zn > N > Fe。（4）土壤pH与梨树叶片中Ca、Mg含量呈极显著正相关,与Zn呈极显著负相关;土壤有机质含量与梨树叶片中N、Mg含量呈极显著正相关;叶片N、K、Ca、Mg、Zn含量与其所对应的土壤有效态养分均呈极显著或显著正相关。     

陕西地区苹果叶营养元素标准范围的确定

 对苹果叶营养水平状况研究表明, N、P、K、Ca、Mg、B 等6 种元素的取值遵从正态分布,Cu、Fe、Mn、Zn 近似X² 分布。对于符合正态分布的元素可用4 点5 分段的概率分级法, 使1～5 级分别对应叶营养元素含量标准值中的缺乏、低值、正常值、高值、过高5 个数值范围, 各级出现的叶样概率分别为10 %、20 %、40 %、20 %和10 % , 其中处在第3 级的叶样占总样本的40 % , 叶分析值在( X - 0.5246S )～ ( X + 0.5246S) 可作为标准值中的正常值范围, 这与通过高产水平果园叶分析值制定的正常值非常接近。对于不符合正态分布的元素, 可参考高产水平果园的叶分析值对概率分级法进行矫正。据此制定出陕西苹果叶营养元素含量标准值, 与国内外标准相比, 陕西标准值表现出N、Ca、Mg、Cu 水平高, P、Zn、Fe、K水平低, Mn、B 基本一致的特点。     

Fruit Fly (Diptera: Tephritidae) Host Status and Relative Infestation of Selected Mango Cultivars in Three Agro Ecological Zones in Uganda

Despite their economic importance, there is paucity of knowledge on fruit fly host status in Uganda. Therefore, this study set out to profile the host range of the main fruit fly pests and determine the susceptibility of selected fruits and mango cultivars across three main mango agro ecological zones, which included: Western Medium High Altitude Farmlands (WMHF), Lake Victoria Crescent (LVC), and the Northern Moist Farmlands (NMF) in Uganda. A wide range of fruits was sampled across the three zones. These were incubated at the National Agricultural Research Laboratories following standard protocols. Emerging fruit fly species were identified using standard keys and counted. Among the sampled fruits, 633 (35.0%) individual fruits from 15 plant families were positive for fruit fly infestation. Bactrocera invadens dominated (76.3%) of the positive samples, while infestation by native species, such as Ceratitis capitata and Ceratitis cosyra, was negligible. Annonaceae, Solanaceae, Rutaceae, and Anacardiaceae plant families recorded significantly more host species, while the number of pest fruit flies (species richness) per plant species followed a similar trend: Solanaceae > Rutaceae > Anacardiaceae. There was significant (P < 0.0001) variability in infestation among mango fruit cultivars, both within and across zones. When all zones were pooled together, Tommy Atkins and Kent, and Keitt, Kate, and Biire were the least and most infested, respectively. In conclusion, fruit flies have a diverse range of commercial and non-commercial hosts in Uganda. Strategies for fruit fly pest eradication in the country should ensure elimination or management of alternative fruit hosts and integration of tolerant mango cultivars in fruit development programs.     

ISSR分子标记与杧果果实生理性病害相关分析

从120条ISSR引物中筛选出9条引物,用以对20个杧果样品进行聚类分析.结果表明,杧果患果实生理性病害品种群体与ISSR分子标记聚类结果相吻合,可利用ISSR分子标记预测杧果果实生理性病害的发生,并作为杧果育种中早期筛选抗果实生理性病害品种的一种有效的辅助手段.     

受大气污染芒果的采后催熟与生理变化

在大气污染环境中生长的芒果，果实采后不能正常完成后熟，成为生产中的新难题。采用0．5％乙烯利，在50℃下浸果5 min后，并在有乙烯气体的环境中保持16 h，然后常温下贮藏，可较有效地促进污染芒果的后熟进程，提高其商品价值。与正常果实相比，受污染芒果的呼吸速率较低，无呼吸高峰出现。综合各处理，发现果肉组织膜透性、果胶甲酯酶活性、呼吸速率等均有提高，果实硬度、果皮色泽也有改善。对这些生理生化变化进行了讨论。