广西柑桔主栽品种对黑腐病抗性的初步鉴定

在1年生脱毒无病苗木春梢上,通过人工喷雾接种采自田间经人工分离纯化的黑腐病菌孢子悬浮液,初步鉴定了14个柑桔品种对黑腐病的抗性.结果表明,贡柑和默科特桔高感,春甜桔和星路比葡萄柚中抗,十月桔高抗,南丰蜜桔、79-2椪柑、兴津温州蜜柑、日南1号温州蜜柑、纽荷尔脐橙、卡拉卡拉脐橙、福罗斯特夏橙、桂橙1号甜橙及沙田柚免疫.     

咸水林场柑桔沙皮病严重发生的原因及防治技术

柑桔沙皮病又称黑点病，病原菌为弱寄生菌，嫩梢、新叶和幼果在造成伤口（冻伤、灼伤、其他伤口）或树势生长衰弱时，遇到多雨潮湿天气时，该病常大量发生。今年咸水林场南丰蜜桔和特早熟温州蜜柑果园普遍不同程度地受到危害，受害果园分别达80％和65％，哈姆林老果园树势较差，受害最严重，     

“果农宝”杀梢素对柑桔杀夏梢效果试验

柑桔是广东省潮州市的主栽品种,也是果农的主要经济来源。柑桔生长过程中,夏梢的生长消耗大量养分,引发梢果矛盾,导致果实脱落,降低产量。因此,为了调控柑桔梢果矛盾,本试验选取"果农宝"杀梢素,采用3个浓度1000倍液、1200倍液、1500倍液,分别对贡柑、沙糖桔、蕉柑、椪柑4个柑桔品种的嫩夏梢进行处理。结果表明:3种浓度处理对贡柑、沙糖桔、蕉柑、椪柑10cm以下新梢,杀死效果均达100%;贡柑及沙糖桔处理最佳浓度1200倍液,而蕉柑及椪柑最佳浓度1000倍液,新梢长度控制在10cm以下,如全园零星抽发的先用人工压除,待全园夏梢抽发量达40%~50%以上才用药。     

应用甲基托布津防治柑桔疮痂病

1973年以来,我场温州蜜柑受疮痂病严重危害,无论春、夏梢叶片、嫩梢和幼果上均有被害,以4—6月间发病严重。叶片初发病时,病斑呈油浸状小点,后渐扩大,显著隆起,呈黄色,木栓化,严重时叶片扭曲变形,以至落叶;果实上的病斑呈显著疣状突起,严重时幼果变黄脱落,影响产量和果实     

4月中旬极端低温过程对柑桔花蕾和新叶的影响

2010年4月中旬湖北省宜昌市夷陵区极端低温过后,调查了夷陵区小溪塔、龙泉、鸦鹊岭,当阳市凤凰山等地低温对柑桔新梢、叶片、花蕾等的影响。结果表明,2.8℃以下,早熟龟井温州蜜柑、椪柑、诺瓦桔和甜橙受到低温冷害,2.5℃以下,中熟尾张温州蜜柑花蕾、新叶受冷害;受害程度龟井温州蜜柑最轻,椪柑、诺瓦桔相当,甜橙最重;花蕾的受害程度重于新叶。     

48%瑞枯霉防治柑桔疮痂病效果试验

莒溪乡是我县柑桔主要产区。全乡种植柑桔4000亩,户均1.5亩。主要品种是宽皮桔类的芦柑和温州蜜柑,而这些品种很容易感染疮痂病,尤以温州蜜柑为甚。发病时间和部位主要在春梢叶片、花辨、花萼和幼果等柔嫩时期。引起落花落果,严重影响柑桔品质和产量。过去防治疮痂病主要掌握二次关键时期进行用药,即第一次在春芽萌动一粒米长时用0.7%等量式波尔多液喷雾,第二     

贡柑黑腐病病原菌的分子鉴定

贡柑黑腐病是近年来在贡柑上发生的一种新型病害,该病害可导致嫩梢快速枯死,大量嫩叶脱落,严重影响树势和产量。本研究从病区采集发病枝叶,对贡柑黑腐病病原菌进行分离、纯化,并采用rDNA-ITS序列分析技术对其进行分子鉴定。结果表明,贡柑黑腐病病原菌为链格孢属Alternaria Nees真菌,rDNA-ITS序列与GenBank中芸薹链格孢菌A.brassicae(Berk.)Sacc.和柑桔链格孢菌A.citri Ellis et Everhart的ITS序列的同源性为99%。结合形态学特征,推断该病原菌为柑桔链格孢菌。     

疮痂病的发生及其防治

疮痂病是山区桔园常见的真菌性病害，主要危害柑桔的嫩叶、嫩梢、幼果等幼嫩组织，严重时引起大量叶片、幼果脱落，影响产量和品质，削弱树势。据１９９１、１９９２年两年统计，我场河坊分场温州蜜柑园春梢受害率分别达４１．８％和３７．２％，幼果受害率达５１．６％和...     

江永县2004年柑桔煤烟病暴发情况调查

江永县2000～2001年柑桔煤烟病暴发成灾，2002年全县统一防治柑桔粉虱1～2代后，病情基本上得到控制。2004年再度暴发，主要发生在椪柑、夏橙、脐橙、温州蜜柑上，其次是江永香柚；发生面积约0．71万公顷，成灾面积0．23万公顷，分别较2001年增加31．23％与15％；春梢病叶率47．22％～100％，早夏梢病叶率80．23％～100％，幼果病果率50．71％～97．12％。     

杧果花期和幼果期病虫害防治及其传粉昆虫的保护

1　果花期和幼果期主要病虫害的防治　果花期和幼果期最主要的病虫害有炭疽病、白粉病、扁喙叶蝉和横线尾夜蛾等。果炭疽病是有潜伏侵染性的病害 ,为害果嫩叶、嫩梢、花和果实 ,是果生长期和后熟期的主要病害之一。其病菌在旧病部越冬 ,由雨水、风或昆虫传播 ,从植株气孔或伤口侵入 ,高温高湿时易大量发生。花穗感病后先出现小斑点 ,后变黑腐烂 ;幼果感病后呈畸形 ,变黑脱落。幼果期入侵的病菌可潜伏至果实后熟期才引发病变。因此 ,该病的早期防治十分重要。果白粉病主要为害花序、幼果和嫩梢。感病部位最初出现分散的白粉状小…     

The anatomy of the fruit in relation to the propensity of citrus species to split

The anatomy of the fruit has been compared in three prone-to-split mandarin hybrids (Nova, Ellendale and Murcott), several cultivars of clementine mandarin (Fino, Clementina de Nules and Orogrande), and in Owari satsuma mandarin. The fruit of the hybrids is oblate to subglobose and usually presents an open stylar end disrupted by a navel formed by the floral meristem, which is conserved near the apex of the fruit. In the non-prone-to-split clementines as well as in Owari satsuma, the floral axis protrudes inside the style, and the flower meristem is lost through abscission shortly after petal fall. The abaxial side of the carpels fuses with the flower axis forming at the stylar end of the fruit a solid tissue which externally has a small scar at the place of style abscission. Most of the fruits in these cultivars have no navel. In addition, the fruit of clementine is slightly oblate or globose. The relevance of these anatomical characteristics as regards to splitting is supported by the differences between the split and non-split fruits in Nova, the split fruit being more oblate in shape and having a bigger navel than non-split fruit. However, the effect of applied growth regulators on fruit splitting could not be correlated with their effect on the anatomy of the fruit. Additional factors not contemplated in the study also influence fruit splitting.     

‘茂谷橘橙’引种观察

对引进良种茂谷橘橙与6个本地柑橘良种进行比较研究,结果表明,茂谷橘橙属特迟熟良种,比芦柑迟熟90d左右;品质好、可溶性固形物达16.6％,可食率达85％;产量高、耐贮藏、挂果期抗寒力较强。     

A role for carbohydrate levels in the control of flowering in citrus

Girdling in October of small or large fruitless branches increased 2–3-fold both starch content of leaves and flower numbers as compared with ungirdled ‘Murcott’ mandarin trees. Autumn girdling and GA₃ treatments were both effective and additive in increasing starch contents of leaves and twigs of ‘Shamouti’ orange trees. GA₃, however, had the expected effect of depressing the reproductive inflorescences in both girdled and ungirdled branches, while girdling had the opposite effect. Girdling and fruit removal in October also additively and dramatically increased flower production in ‘Murcott’. Lowtemperature regimes in a phytotron caused young ‘Minneola’ budlings to flower earlier in the season and more profusely, while having no effect on starch content of leaves and twigs. The interactions of increased carbohydrate content and gibberellin in the control of flower formation in citrus are discussed.     

砧木对椪柑生长结果及叶片矿质成分的影响

通过10年田间比较试验,探明枳砧与2种惯用乔化砧(椪柑、福桔)对椪柑生长结果及叶片元素含量的影响。枳砧明显抑制椪柑树体及新梢生长,而显著增加其开花、坐果数及单株产量,且产量较稳定。半矮化枳砧椪柑叶片含氮、锰量稳定高于2种乔化砧椪柑;而前者的叶片含钾量较稳定高于后两者,含钙量呈阶段性低于后两者;镁、磷、铜、铁、硼含量差异不稳定、锌无差异。     

Changes in activity of polyamine biosynthetic enzymes and in polyamine contents in developing fruit tissues of ‘Murcott’ mandarin

Arginine decarboxylase (ADC), ornithine decarboxylase (ODC), putrescine (Put) and spermidine (Spd) contents were analysed in growing ‘Murcott’ mandarin fruits from bloom to full development. Enzymes of polyamine synthesis and, to a lesser extent, polyamine contents roughly followed patterns of growth activity in fruit tissues, with a maximum at the early stages, a minimum at mid-summer and intermediate values at full fruit development. ADC/ODC and Put/Spd ratios were 2–8 and 2–30, respectively. Possible links between polyamine metabolism and citrus fruit set and development are suggested.     

The influence of fruiting on the bud sprouting and flower induction responses to chilling in Citrus

Summary

The effect of chilling temperatures on bud sprouting and flower formation was compared on fruiting and non-fruiting ‘Owari’ satsuma mandarin (Citrus unshiu Marc) trees. On non-fruiting trees, bud dormancy was weak, and a significant proportion of buds were able to sprout at high temperatures without being chilled. Separate effects of low temperatures on bud sprouting and flower induction were demonstrated. On fruiting trees these two effects of low temperatures were also demonstrated on summer-flush buds, but not on older (spring-flush) buds. The spring-flush buds from fruiting trees scarcely sprouted without being chilled. These buds required a longer chilling period for dormancy release than for flower induction, and it was not possible to separate the effect of low temperature on flower induction from the effect on dormancy release. The presence of fruit reduced flower formation by reducing bud sprouting. Furthermore, fruit had a direct inhibitive effect on vernalization which resulted in increased formation of vegetative shoots. The effect of fruit and low temperature on flowering was unrelated to carbohydrate accumulation in the leaves or the roots.     

柑橘落花落果的营养元素含量及其脱落损耗

 以成年纽荷尔脐橙、兴津温州蜜柑和沙田柚为材料,研究落蕾、落花和脱落幼果中的养分 含量及其脱落造成的损耗。结果表明,3 个品种的蕾和花营养元素含量为N 3.34% ~ 3.66%,P 0.26% ~ 0.31%,K 1.67% ~ 2.30%,Ca、Mg 和S 含量0.17% ~ 0.48%,Fe、Mn、Zn、Cu 和B 含量8.1 ~ 87.5 mg · kg^-1。 除花的B 含量显著高于蕾外,花和蕾的多数营养元素含量相近,且品种间差异小。与蕾和花相比,幼果 的N 和P 含量较少,N 和P 含量分别少21.8%和19.5%,但Fe 含量较多,其它营养元素含量变化不明显。 纽荷尔脐橙、兴津温州蜜柑和沙田柚单株脱落的蕾、花和幼果干物质量合计分别为3 016.3 g、3 533.6 g 和1 486.7 g,由此所造成的单株主要养分损耗为N 49.2 ~ 119.4 g、P 4.3 ~ 10.1 g、K 30.1 ~ 76.2 g、Mg 2.5 ~ 7.1 g、Zn 24.0 ~ 81.5 mg 和B 65.5 ~ 170.2 mg。兴津温州蜜柑和沙田柚均以落花的养分损耗最大,落蕾其 次,落果最小;纽荷尔脐橙则是落花和落蕾的养分损耗相近且远高于落果。品种间以兴津温州蜜柑脱落 的养分损耗最大,纽荷尔脐橙其次,沙田柚最小。因此,柑橘应控制过量开花,并在萌芽开花期及时补 充养分。     

“国庆1号”温州蜜柑结果母枝状况与结果的关系

选用20 a生“国庆一号”温州蜜柑盛果多花中庸树,随机取样调查结果母枝粗度、长度、其上有叶结果枝和无叶结果枝数量、有叶结果枝叶数、长度以及它们的坐果率.结果表明:有叶结果枝及无叶结果枝数不随结果母枝粗度的增加而有规律的增减,但随母枝长度的增加有减少的趋势.结果母枝粗度在0.4～0.5 cm范围内,有叶结果枝和无叶结果枝坐果率都最高,分别为7.8％和27.5％.结果母枝长度在0.1～10 cm范围内,有叶结果枝和无叶结果枝坐果率都最高,分别为7.0％和21.5％.结果母枝粗度与有叶结果枝及无叶结果枝坐果率无显著相关关系.母枝长度与有叶结果枝坐果率无显著相关关系,但与无叶结果枝坐果率呈显著正相关.有叶结果枝叶片数越少的有叶结果枝数反而越多,有叶结果枝叶数与有叶结果枝数呈显著正相关;总的来说,叶数越多,有叶结果枝坐果率越高.以短有叶结果枝数量大,但有叶结果枝长度与有叶结果枝坐果率呈显著正相关.     

辣椒采后病害发生情况

从广东省广州、增城采收辣椒,在常温（25 ℃）贮藏条件下观察辣椒采后病害的发生情况,测定采收时无病害症状的辣椒组织中病菌的潜伏侵染率。结果表明：辣椒采后在25 ℃下贮藏,发生的病害有果腐病（Fusarium sp.）、炭疽病（Colletotrichum gloeosporioides）、软腐病（Erwinia carotovora）、黑斑病（Alternaria alternata）、疫病（Phytophthora capsici）、灰霉病（Botrytis cinerea）,且5 d后开始表现病害症状。其中果腐病、炭疽病、软腐病是辣椒采后的主要病害。辣椒采后病害主要从果柄部位开始发生,向果蒂和果身部位扩展,最后引起整个辣椒果实腐烂。辣椒果柄、果蒂是带有潜伏侵染菌较多的部位,从果柄、果蒂组织中分离出的病菌有炭疽病、链格孢菌、镰刀菌、灰葡萄孢菌和欧氏杆菌,从果身组织中只分离出炭疽菌、链格孢菌和欧氏杆菌。伤口是辣椒采后病害病原菌侵入的主要通道,伤口接种的处理发病率高,无伤口接种的处理不发病。剪除果柄可明显减轻辣椒采后病害的发生,提高辣椒的贮藏效果。     

依据多倍体形态特征快速高效发掘柑橘四倍体

基于柑橘多胚性品种存在珠心细胞自然加倍的特点，建立了基于种子催芽、生长室实生播种、幼苗“观根辨叶看油胞”形态初选和流式细胞仪倍性鉴定的发掘柑橘四倍体的快速方法。采用该方法，分别从无酸甜橙、红江橙、贡柑、年橘、新会柑、滑皮金柑的432、506、1 356、1 870、2 749和685株实生苗中，发掘出疑似四倍体5、6、5、17、45、7株；通过倍性检测，从上述6个品种分别获得四倍体4、5、5、14、39、5株，形态初选准确率分别为80.0%、83.3%、100.0%、82.4%、86.7%和71.4%。与之前的四倍体发掘方法相比，本方法四倍体初选准确率高，并且从种子播种到获得四倍体植株耗时不超过40 d。SSR分子鉴定表明，所鉴定的四倍体均来自其二倍体品种珠心细胞自然加倍形成的双二倍体，为柑橘三倍体无核育种提供了珍贵的四倍体亲本资源。