CPPU对猕猴桃果实组织发育及内源细胞分裂素含量的影响

对经生长调节剂ＣＰＰＵ处理的猕猴桃果帝进行了组织学及内源细胞分裂素含量变化的研究。结果表明：处理后的果帝细胞分裂时期延长,细胞的数目增多,体积增大;处理果实中,内源细胞分裂素的含量在果肉细胞分裂盛期及其之后都有所增高。     

Fate of 15N-labelled nitrogen fertilizer applied to kiwifruit (Actinidia deliciosa) vines

The fate of ¹⁵N-labelled ammonium fertilizer applied once to six-year-old field-grown kiwifruit (Actinidia deliciosa Hayward) vines was measured over three years. The three main treatments were nitrogen (N) applied singularly at 100 or 200 kg N ha^–1 in early spring (two weeks before bud burst) or split with 100 kg N ha^–1 (unlabelled) in early spring and 100 kg N ha^–1 (¹⁵N-labelled) ten weeks later. All N treatments were applied to vines with a history of either 50 or 200 kg N ha^–1 yr^–1. For three years after ¹⁵n application, components of the vines and soil (0–600 mm depth) were sampled at harvest in late autumn and the N and ¹⁵N contents determined.By the first harvest, all plant uptake of ¹⁵N had occurred and this represented 48–53% of the ¹⁵N applied. There was no significant effect of current N fertilizer treatment or of N history on ¹⁵N recovery by vines. Removal of ¹⁵N in harvested fruit was small at 5–6% in the first year and 8% over 3 years. After 2–3 years, most plant ¹⁵N occurred in the roots and this component declined only slowly over time. In contrast, there was a large temporal decline in ¹⁵N in above-ground plant components due to the annual removal in leaf fall and pruning. An associated experiment showed that when ¹⁵N-labelled prunings and leaves were mulched and returned to the soil, only about 9% was recovered by plants within 2 years. Almost all remaining mulched material had been immobilised into the soil organic N.In all treatments, about 20% of the added ¹⁵N remained in soil at the first harvest. This was almost entirely in organic fractions (<0.4% in inorganic N) and mostly in the surface 150-mm layer. The ¹⁵N content in soil changed little over time (from 20 to 17% between the first and third harvests respectively) and indicated that most of the N had been immobilised into stable humus forms.     

Restriction fragment length polymorphisms in the genusActinidia (Actinidiaceae)

A series of chloroplast and nuclear probes were used to examine restriction fragment length polymorphisms (RFLPs) in kiwifruit (Actinidia deliciosa) and three of its closest relatives. The four species fell into two pairs, withA. chinensis andA. deliciosa closely related but some distance away from the other two species,A. latifolia andA. eriantha. The results are consistent with the hypothesis that the diploid species,A. chinensis, is a precursor ofA. deliciosa, which is hexaploid.     

猕猴桃实生苗再生体系的建立

以成熟饱满的美味猕猴桃种子发芽获得实生苗,分别以实生苗的茎段、叶柄和叶片为材料建立了再生体系。结果表明:种子以2.5mg/L的赤霉素(GA3)处理8h较适合;以培养基发芽较为适合;茎段、叶柄和叶片的愈伤组织的诱导率均为100%,且茎段、叶柄比叶片容易脱分化,但叶片的平均出苗率最高。再生苗在移栽5d后,开始长出新叶,10d后就能完全适应外界环境。     

猕猴桃属16个雄性材料遗传多样性的ISSR分析

利用ISSR分子标记对雄性猕猴桃16个材料进行遗传多样性分析。从100条引物中筛选出10条引物用于ISSR扩增,共扩增出172条带,其中多态性条带140条,多态性百分率为81.4%;经POPGENE 1.32软件分析结果显示,16个雄性猕猴桃材料的遗传距离在0.1503~0.5128之间,平均Nei's基因多样性指数(H)为0.2416,平均Shannon信息指数(I)为0.4048;聚类分析结果显示,在遗传相似系数为0.64处可将供试材料分成4类,第Ⅰ类为中华和美味猕猴桃,第Ⅱ类为阔叶、毛花猕猴桃,第Ⅲ类为魁绿猕猴桃,第Ⅳ类为四萼猕猴桃。结果表明ISSR可用于雄性猕猴桃遗传多样性研究,该研究结果可为猕猴桃种质资源的进一步开发利用提供重要信息。     

Fe-EDDHA对矫治秦美猕猴桃叶片失绿和营养元素组成的影响

在陕西石灰性土壤秦美猕猴桃果园施用不同剂量叶绿灵 (Fe- EDDHA) ,结果表明 ,萌芽期株施 45 g叶绿灵对矫治秦美猕猴桃叶片失绿黄化效果显著 ,可一直维持到当年落叶。同黄化对照植株相比 ,叶片叶绿素含量增加 1 82 .5 % ,活性铁含量提高 5 3 .2 % ,果实品质得到明显改善。施用叶绿灵还改善了叶片营养元素的含量     

乙酰水杨酸和乙烯处理对猕猴桃果实后熟软化的影响

以猕猴桃（Actinidia deliciosa(A.Chev.)C.F.Liang et A.R.Ferguson cv.Bruno)果实为试材,研究乙酰水杨酸（ASA）与乙烯处理对果实内源水杨酸（SA）含量变化以及后熟软化相关因子的影响,探讨SA在果实成熟衰老进程的作用。研究结果表明：果实后熟软化进程中,内源SA水平呈下降变化,组织中SA水平与果实硬度变化呈极显著正相关关系（r=0.9694),ASA处理可显著地维持组织中较高的SA水平,抑制脂氧合酶（LOX）和丙二烯氧合酶（AOS）活性增加,减低O2^-生成速率,维持细胞膜稳定性,进而抑制了乙烯生物合成或推迟乙烯跃变的到来,延缓了果实后熟软化进程,这些效应主要表现在乙烯跃变之前或乙烯跃变前期;相反,外源乙烯处理则显著降低果实组织中内源SA水平,促进LOX和AOS活性的增加,促使O2^-积累,增加了细胞膜透性,促使乙烯跃变的提前到来,加速了果实的后熟软化。推测组织中的内源SA水平与细胞膜脂过氧化作用密切相关,外源ASA可能作为一种O2^-等自由基的清除剂或是细胞膜稳定剂在组织成熟衰老过程中起作用。     

乙酰水杨酸处理对猕猴桃果实成熟衰老的影响及其作用机理

以不同后熟软化阶段猕猴桃果肉组织圆片为材料 ,在 2 0℃下用 1.0mmol L(pH 3.5 )的乙酰水杨酸(ASP)分别处理 4、12和 2 4h后 ,分析其对果实成熟衰老相关因子的影响。结果表明 ,随着果实成熟衰老 ,内源游离SA下降 ,LOX活性增加 ,超氧自由基 (O- ·2 )生成速率增加 ,乙烯释放量加大 ;ASP处理促使组织内源SA水平的增加 ,降低了O- ·2 生成速率 ,抑制了LOX、ACC合成酶和ACC氧化酶的活性以及乙烯的生成。推测ASP可能作为O- ·2 等自由基清除剂 ,通过负反馈调控LOX途径 ,延缓果实的成熟衰老     

峨眉山野生猕猴桃种质资源调查

在对峨眉山猕猴桃资源调查基础上,探明了野生猕猴桃在峨眉山的种类和地理分布情况,并对峨眉山猕猴桃种类繁多的原因进行初步分析,为研究猕猴桃生长条件及环境因素,进行野生猕猴桃的引种驯化和人工栽培提供依据。     

Isolation and identification of pathogenic fungi causing postharvest fruit rot of kiwifruit (Actinidia chinensis) in China

Kiwifruit is a very important commercial crop in China, which is the largest producer of the fruit in the world. The rapid expansion of areas of kiwifruit cultivation has resulted in the spread of postharvest rot diseases. To clarify the pathogens causing kiwifruit postharvest rots in China, 76 pure strains were isolated from 138 rotten fruits during the shelf‐life period, with fruit collected from the 11 main regions of kiwifruit cultivation (Shaanxi, Sichuan, Henan, Guizhou, Hubei, Anhui, Jiangxi, Hunan, Fujian, Zhejiang and Jiangsu provinces) during 2014–2015. By examining the morphological and microscopic characteristics together with the results of pathogenicity testing and ITS (internal transcribed spacer) sequencing, four species were identified as the main pathogens causing kiwifruit postharvest rots in China. They were Phomopsis sp., Botryosphaeria dothidea, Alternaria alternata and Pestalotiopsis microspora, with identification rates of 52.6%, 23.7%, 13.2% and 10.5%, respectively. All isolates inoculated on wounded fruit were pathogenic but non‐pathogenic when peels were unwounded except B. dothidea. These findings have important implications for resistance breeding and control of kiwifruit postharvest rots in China.