几种综合施肥措施对早熟温州蜜柑生长和产量的影响

对广西国有良丰农场十二年生早熟温州蜜柑采用几种施肥方法,比较不同施肥措施下,该地区早熟温州蜜柑各个物候期的生长发育情况和果实产量。结果表明:处理4分别在各个物候期前进行5次合理的氮、磷、钾配方施肥,明显影响果树的生长发育情况,果实成熟期相对提前;平均单果重量增加,达到125 g/个;平均单株产量明显增加,达到93.60 kg/株;平均产量最高,为73.94 t/hm~2。因此,针对该地区独特的地理气候环境,适合于该地区的合理施肥方式对于提高果树产量和增加经济收入显得尤为重要。     

桂林市沙糖橘叶片的营养元素丰缺状况研究

为了解桂林市沙糖橘产区的叶片营养元素的丰缺状况,并为桂林市沙糖橘的合理施肥提供一定的理论依据,于2017年调查分析了桂林市沙糖橘产区6个县60个果园叶片的氮(N)、磷(P)、钾(K)、钙(Ca)、镁(Mg)、硼(B)、铁(Fe)、锰(Mn)、铜(Cu)、锌(Zn)的含量状况。结果显示,桂林市沙糖橘叶片中N、P、K、Ca、Mg、B、Fe、Mn、Cu、Zn的平均含量分别为：(29.92±0.36)、(1.23±0.01)、(14.54±0.78)、(32.96±1.03)、(2.67±0.10) g.kg-1和(95.77±4.72)、(50.64±8.57)、(77.42±5.70)、(4.70±0.59)、(15.72±0.95)mg.kg-1.。其中,N和B含量普遍偏多,位于高量和过量水平的果园比例分别为43.33%和78.33%;P、K、Ca、Mg、Cu和Zn的含量普遍存在偏少现象,位于低量和缺乏水平的果园比例分别为38.33%、35.00%、40.00%、43.33%、65.00%和81.67%;Fe和Mn的含量适中的果园比例分别为65%和66.67%,均同时存在偏多或偏少的现象。桂林市沙糖橘产区树体营养元素失衡现象普遍存在,生产上应减少N和B肥的用量,重视补充P、K、Ca、Mg、Cu、Zn肥,合理施用Fe和Mn肥,以确保树体营养均衡,实现沙糖橘的优质丰产。     

广西南丰蜜桔园营养状况及其对果实品质的影响研究

对广西南丰蜜桔园土壤样品、叶片样品和果实样品进行检测分析。结果表明,所研究的南丰蜜桔园土壤pH普遍偏酸;土壤有机质、有效磷、有效锌、交换性钙含量较高;碱解氮和有效钾含量中等;交换性镁、有效硼含量较低;柑桔叶片氮含量大部分低于适量范围,而磷、钾含量大部分处于适量范围,少量处于高量水平;柑桔园土壤pH值与土壤交换性钙和交换性镁分别呈显著和极显著正相关性,土壤有机质与碱解氮呈显著正相关;土壤有效锌和有效钾含量与果实可溶性固形物含量呈极显著正相关,交换性钙含量与可溶性固形物呈显著正相关,而pH值和有机质与可溶性固形物呈显著负相关;叶片中钾素与果实Vc呈显著正相关。该研究结果将为广西南丰蜜桔的科学施肥提供参考。     

鳜鱼和奥利亚罗非血乳酸脱氢酶酶谱的比较

哺乳类动物各种组织和器官的乳酸脱氢酶(LDH)同工酶较稳定,酶带分布非常有规律,同源组织的LDH同工酶酶谱通常相似和稳定。鱼类LDH同工酶复杂得多,有三分之二品种中,其LDH同工酶类似哺乳类动物的酶谱;但在其余三分之一种类中,两个亚基随机结合受到限制,出现了不规则酶谱,有的只有2—3条酶带,有的超过5条酶带。即使具有5条酶带的鱼中,其骨骼肌和心肌LDH在电泳酶谱上迁移快慢正好与哺乳类动物相反。此外鱼类C基因产物并不特定在某一组织或器官中,一些鱼的     

3种保鲜剂处理对“杨小-2,6”采后生理及贮藏效果的影响

本文采用壳聚糖、水杨酸和茉莉酸甲酯三种不同天然保鲜剂处理,研究了它们在冷藏（5±1℃）条件下对“杨小-2,6”南丰蜜橘果实采后生理生化及贮藏效果的影响。实验结果表明：1.5%壳聚糖处理的果实保水性最好,出现烂果的时间最晚;0.1g/L水杨酸处理的果实可溶性固形物、呼吸强度在贮藏期间波动是最小的,可溶性蛋白质达到最大峰值;10μmoL/LMeJA处理的果在可溶性固形物、总糖、可滴定酸、Vc、可溶性蛋白质等多项生理指标上都表现出最佳效果。     

Alternaria Brown Spot of Minneola in Greece; Evaluation of Citrus Species Susceptibility

During the last three years, a new disease was observed in northwestern Greece on Minneola trees, hybrid of mandarin and grapefruit. On May small brown necrotic leaf spots surrounded by yellow halo areas of various sizes appeared and covered a major portion of the leaves with extension of necrosis into the veins. On young fruits small, slightly depressed black spots were the first symptoms, which later became 2–7 mm in diameter. Brown spots were observed on the leaves and fruits in several orchards in the same area, causing leaves and fruits to drop. In some orchards over 50% of the fruits were affected. From the fruit and leaf spots the typical small-spore species Alternaria alternata was isolated. Pathogenicity tests were performed by artificially inoculating fruits of Minneola, common mandarin and Clementine. The symptoms of the disease were reproduced only on fruits of Minneola hybrids by the specific strain of the fungus Alternaria alternata pv. citri. Different citrus susceptibility tests indicated that mandarins Minneola, Nova and Page were very susceptible to tested isolates while Clementine SRA and Poros Clementine were not. All lemons and lime Seedless were not susceptible. Grapefruit New Hall was not susceptible, while the Star Ruby was. Orange Lane Late, Navel Late, Oval Poros, Olinda, Navel Athos were not susceptible and only Moro showed reaction being slightly susceptible only to one isolate.     

砂糖橘上碎叶病毒外壳蛋白基因的克隆及序列分析

利用RT-PCR技术对广东砂糖橘碎叶病毒的外壳蛋白(CTLV-CP)基因进行了克隆和测序分析。DNA序列分析表明,砂糖橘CTLV-CP基因的cDNA序列全长为786bp,编码262个氨基酸。BLAST分析结果显示,所得序列与苹果、梨茎沟病毒(ASGV)外壳蛋白基因及其它柑橘CTLV-CP基因的同源性在87%～91%,证明所克隆的片段为CTLV-CP基因。     

Zinc Nutrition in ‘Nagpur’ Mandarin on Haplustert

ABSTRACT

Zinc (Zn) deficiency is the most prevalent nutritional disorder in citrus orchards world over. The management strategy of Zn deficiency today is still governed by the efficacy of two conventionally used methods of Zn supply to plants via soil or foliar fertilization. A field experiment with 12-yr-old ‘Nagpur’ mandarin (Citrus reticulata Blanco) orchard was, therefore, carried out during 2004–07 comparing soil application versus foliar application of Zn, each at three levels viz., 100, 200, and 300 g tree^?1 with constant doses of N (600 g tree^?1), P (200 g tree^?1), K (300 g tree^?1), and Fe(60 g tree^?1) on Haplustert soil type with reference to response on flowering intensity, fruit set, tree volume, fruit yield, changes in soil fertility/leaf nutrient status, fruit quality, and transformation of native soil Zn fractions. Soil application of Zn at all the three levels, produced significantly higher increase in tree volume over foliar application on equivalent rates viz., T₁ (2.53 m³) vs. T₄ (2.06 m³) and T₂(4.30 m³) vs. T₅ (2.23 m³). The yield-determining parameters like flowering and fruit set intensity (no. m^?1 shoot length) were, respectively, much higher with soil applied (135.74 and 21.90) than foliar applied Zn (31.20 and 11.6). These observations set the favorable conditions required for yield response, e.g., all the three treatments involving soil application of Zn, T₁ (32.1 kg tree^?1), T₂ (52.6 kg tree^?1), and T₃ (51.8 kg tree^?1) were correspondingly superior over T₄ (22.5 kg tree^?1), T₅ (34.3 kg tree^?1), and T₆ (42.1 kg tree^?1) as foliar application treatments. All the three major fruit quality parameters (juice, acidity, and TSS) were likewise more influenced by soil application than foliar application of Zn. Improvements in soil Zn fractions (mg kg^?1) viz., exchangeable Zn (0.25–0.60), complex-Zn (2.71 to 4.86), organically bound Zn (0.86 to 2.0), and Zn-bound to carbonates and acid soluble minerals (2.56–4.96) were observed in response to Zn fertilization with treatments T₁–T_3. On the other hand, foliar applied Zn treatments (T₄–T₆) produced no such changes in any of the soil Zn fractions.     

锌对砂糖橘果实发育过程细胞壁代谢的影响

为研究不同锌处理对砂糖橘果实发育成熟过程中果皮硬度、细胞壁结构物质及其相关酶活性的影响,以四年生砂糖橘（Citrus reticulata Blanco cv. Shatangju）为试材,在果实膨大期喷施不同锌肥,同时对与果皮力学性能相关的细胞壁代谢变化规律进行分析。结果表明,不同锌处理均可降低果实发育成熟过程中果皮硬度的变化幅度,降低多聚半乳糖醛酸酶（PG）、纤维素酶（Cx）、果胶甲酯酶（PE）的活性,其中Zn2++Ca2+处理的果皮硬度变化最均匀、陷痕果高发期Cx和PE活性低、原果胶和纤维素含量高。不同锌处理均可有效地降低果实发育成熟过程中细胞壁代谢酶的活性,抑制原果胶和纤维素的降解,延缓细胞壁水解,使得果实硬度变化更均匀,其中Zn2++Ca2+处理的效果最明显。